Home

Distribution Agreement In presenting this thesis

1. 34 E Future Studies 35 F Conclusions 36 5 REFERENCES 36 6 NON PRINT SOURCES 39 7 TABLES amp FIGURES 40 8 APPENDICES 46 A Standard Operating Procedure for BEAT Dust Collection 46 B PBDE GC MSD Instrument Method Details 56 1 IN A Ba retard have banne that a 2006 brom Birn depen decab and in and d prese BDE polyu NTRODUCT ackground Polybrom dants frequen a chemical s ed in the Un are environm 209 PBDE mines around nbaum and H ndent on the bromodiphen Three maj nternationall decabromodi ent Birnbaum 47 tet
2. 14 E Child Handwipe Samples 15 Handwipe Collection 15 Handwipe Extraction 15 F Dust and Handwipe PBDE Quantification 16 G Data Analysis 16 3 RESULTS 17 A Demographic Data 17 B Serum PBDE Distributions 18 C Serum PBDE Associations 21 Statistical Analysis 21 Age and Serum PBDE Concentrations 21 Sex and
3. 37 Frederiksen M Vorkamp K Thomsen M Knudsen LE 2009 Human internal and external exposure to PBDEs A review of levels and sources Int J Hyg Environ Health 212 2 109 134 Talsness CE 2008 Overview of toxicological aspects of polybrominated diphenyl ethers A flame retardant additive in several consumer products Environ Res 108 2 158 167 Chen AM Chung E DeFranco EA Pinney SM Dietrich KN 2011 Serum PBDEs and age at menarche in adolescent girls Analysis of the National Health and Nutrition Examination Survey 2003 2004 Environ Res 111 6 831 837 Branchi I Capone F Alleva E Costa LG 2003 Polybrominated diphenyl ethers Neurobehavioral effects following developmental exposure Neurotoxicology 24 3 449 462 Boas M Main KM Feldt Rasmussen U 2009 Environmental chemicals and thyroid function an update Curr Opin Endocrinol Diabetes Obes 16 5 385 391 Trudel D Scheringer M von Goetz N Hungerbuhler K 2011 Total Consumer Exposure to Polybrominated Diphenyl Ethers in North America and Europe Environmental Science amp Technology 45 6 2391 2397 Birnbaum LS Staskal DE 2004 Brominated flame retardants cause for concern Environ Health Perspect 112 1 9 17 Turyk ME Persky VW Imm P Knobeloch L Chatterton R Anderson HA 2008 Hormone Disruption by PBDEs in Adult Male Sport Fish Consumers Environ Health Perspect 116 12 1635 1641 Hagmar L Bjork J Sjodin A Bergman A Erfurth EM 2001 Plasm
4. 5 Child Serum PBDE 6 Exposure Routes and Potential Measurement Methods 7 D Aims and Hypotheses 9 2 METHODS AND MATERIALS 10 A Study Population and Enrollment 10 B Chemicals and Materials 11 C Blood Samples 12 Blood Sample Collection 12 Serum PBDE Extraction and Quantification 12 D Household Dust Samples 14 Dust Sample Collection 14 Dust PBDE Extraction
5. B Chemicals and Materials Chemicals used for sample extraction and analysis are listed in Table 1 For serum extractions internal standard ISTD solution was 10 ng mL of 13C12 isotopically labeled BDE 47 99 100 153 and 154 in methanol For dust and handwipe extractions ISTD solution was 20 ng mL of 13C12 isotopically labeled BDE 47 99 100 153 and 154 in hexane Low QCL and high QCH concentration quality control solutions were 100 ng mL and 300 ng mL respectively of BDE 47 85 99 100 153 and 154 in hexane ISOLUTE brand bulk silica sorbent United Kingdom and ISOLUTE 200 mg Silica 10 mL XL columns United Kingdom used during sample clean up were purchased from 12 Biotage AB Supelclean ENVI Florisil 500mg 3mL SPE cartridges for handwipe extraction were purchased from Supelco Bellefonte PA Ottawa sand 20 30 mesh for accelerated solvent extraction was purchased from Fisher Scientific Fair Lawn NJ C Blood Samples Blood Sample Collection While the child was still under general anesthesia after surgery the nurse collected 15 mL of blood in two tiger topped serum separator Vacutainer tubes Blood samples were transported to the Barr Ryan laboratory at the Rollins School of Public Health Emory University on the day of collection and immediately processed As described by Virginia 2012 serum was separated aliquoted into freezer safe storage vials and stored at 20
6. r 0 607 and p 0 0278 The correlation between handwipe and serum BDE 99 concentrations was significant at the 0 10 level r 0 518 p 0 0640 27 4 DISCUSSION A Serum PBDE Study Design Only four studies investigating serum concentrations of PBDEs in young American children currently exist Lunder et al 2010 Rose et al 2010 Eskenazi et al 2011 Stapleton et al 2012 Three of the studies were undertaken in study populations that are not representative of the general American public Lunder et al 2010 studied 20 mother child pairs the majority of whom were high SES white Caucasians Eskenazi et al 2011 evaluated PBDEs in 7 year olds from a low income Mexican American agricultural group as a part of the Center for Health Assessment in Mothers and Children of Salinas CHAMACOS study Rose et al s 2009 study population was selected from the Childhood Autism Risks from Genetics and the Environment CHARGE study and included autism and developmental delay cases and matched controls from California This study adds to the literature by providing a more diverse study population with a large sample size to test for potential predictors of exposure 33 African American children were enrolled representing the largest number to date SES as determined by insurance status was mixed for this population with approximately 63 on Medicaid In Lunder et al 2010 all children were breastfed in t
7. BDE 47 and 99 had the highest median concentrations and were the most frequently detected congeners which is consistent with the literature Rose et al 2010 Stapleton et al 2012 When compared to values found in the previous four studies BDE 47 median concentration fell in the middle Figure 9 Both the CHARGE and CHAMACOS groups had higher median concentrations of serum BDE 47 Rose et al 2010 Eskenazi et al 2011 This is likely due to both study populations being located in California where exposure tends to be higher because of strict fire regulations resulting in the high use of flame retardants Zota et al 2008 listed repor conce Stapl with activi Figu Table 8 Si Covariates Significant Sex Race Breastfeed BMI A list of c d in Table 8 rted mixed re entrations at leton et al 2 age perhaps ity but Rose 0 10 20 30 40 50 60 70 80 Median Concentration ng g lipid ure 9 Media Stapleton e gnificant Asso s of Interest t Covariates ding History covariates th Age was no esults with r 2 6 to 3 yea 2012 BDE s because of e et al 2009 Rose et al 2009 an serum BD t al 2012 w ociations betw Congener 47 PBDE 100 47 153 hat were sign ot a significa egard to age ars of age co E 47 99 1 f accumulatio 9 foun
8. C until analysis Serum PBDE Extraction and Quantification PBDEs were extracted from serum using solid phase extraction SPE and a clean up method to remove biological contaminants before analysis 1 mL of each serum sample was spiked with 100 L of ISTD 10 ng mL and 100 L of formic acid and vortex mixed briefly 5 mL of hexane was added to each sample and then vortex mixed at 2000 rpm for 10 minutes An additional 5 mL of hexane was added and samples were vortex mixed for an additional 5 minutes Serum clean up used acidified silica columns prepared in house Pre packed ISOLUTE 200 mg silica columns were used as the base Acidified silica was produced by 13 combining 98 H2SO4 and ISOLUTE bulk silica 1 2 1 8 g of acidified silica was layered on top of the premade silica columns followed by 0 5 g of anhydrous Na2SO4 The columns were dried overnight at 100 C Columns were conditioned with 5 mL of hexane before addition of samples Samples were briefly vortex mixed and manually shaken prior to loading in the column Samples tubes were rinsed with 1 mL of hexane vortex mixed and shaken and loaded into the column The sample breakthrough was collected in clean 15 mL tubes The eluates were evaporated at 30 C at 15 psi The 15 mL collection tubes were replaced by clean tubes and the columns eluted again with 10 mL of 1 19 dichloromethane DCM hexane solution The eluate was collected and combined wi
9. Distribution Agreement In presenting this thesis or dissertation as a partial fulfillment of the requirements for an advanced degree from Emory University I hereby grant to Emory University and its agents the non exclusive license to archive make accessible and display my thesis or dissertation in whole or in part in all forms of media now or hereafter known including display on the world wide web I understand that I may select some access restrictions as part of the online submission of this thesis or dissertation I retain all ownership rights to the copyright of the thesis or dissertation I also retain the right to use in future works such as articles or books all or part of this thesis or dissertation Signature Grace E Lee ______________ Date Predicting Body Burden of Polybrominated Diphenyl Ethers in Children Aged 15 Months to 5 Years Using Household Dust and Handwipe Levels and Selected Demographic Variables By Grace Evelyn Lee MPH Environmental Health Dana Boyd Barr Ph D Committee Chair __________________________________________________________ Paige Tolbert Ph D Committee Member Predicting Body Burden of Polybrominated Diphenyl Ethers in Children Aged 15 Months to 5 Years Using Household Dust and Handwipe Levels and Selected Demographic Variables By Grace Evelyn Lee B A Kenyon College 2009 Thesis Committee Chair Dana Boyd Barr Ph D An abstract of A thesis submitted to the Faculty of the Rollins Sch
10. 54 110 78 85 5 04 2 17 7 12 0 28 20 18 99 8 76 6 20 7 20 1 46 23 18 100 0 57 0 60 0 18 0 37 0 87 153 1 34 1 05 0 79 0 63 2 49 154 4 78 3 34 2 69 2 78 9 52 SUM 55 33 37 16 52 01 11 19 166 52 Other 9 47 39 49 32 56 22 77 15 56 86 40 85 0 67 0 61 0 29 0 42 1 42 99 9 50 8 78 5 24 3 55 19 57 100 3 31 2 75 3 48 0 25 9 88 153 8 90 6 67 8 16 1 65 26 12 154 0 93 0 95 0 13 0 68 1 06 SUM 62 81 61 51 33 82 24 60 122 48 Insurance Medicaid 51 47 56 09 33 92 89 63 0 07 642 13 85 1 21 0 64 2 34 0 37 16 41 99 16 20 9 91 27 23 1 46 193 57 100 10 57 6 82 17 95 0 25 125 79 153 12 31 7 68 15 07 1 65 78 81 154 1 97 1 06 3 31 0 63 22 89 SUM 98 35 63 39 149 31 11 19 1079 61 Private 30 47 50 47 40 33 47 13 0 10 193 85 85 0 89 0 65 1 37 0 31 8 06 99 13 04 8 31 12 71 0 31 52 13 100 7 51 5 37 7 71 0 24 29 21 45 153 7 14 4 82 5 95 2 33 26 12 154 1 10 1 08 0 35 0 51 1 97 SUM 80 15 62 18 68 33 5 74 275 40 Breastfeeding Status No 33 47 74 28 47 55 111 75 7 68 642 13 85 1 43 0 64 3 02 0 31 16 41 99 19 18 11 18 33 06 2 22 193 57 100 12 18 6 81
11. 88 41 72 09 62 43 11 19 237 33 Sex Male 46 47 38 36 29 11 32 61 0 07 149 36 85 0 80 0 63 0 70 0 38 3 95 99 12 03 8 00 11 94 0 31 55 37 100 6 71 5 01 6 69 0 24 24 82 153 9 36 4 89 11 56 1 65 69 37 154 1 40 1 06 1 20 0 63 8 16 SUM 68 67 57 58 54 22 5 74 251 99 44 Female 35 47 74 57 47 65 107 49 4 54 642 13 85 1 48 0 65 2 97 0 31 16 41 99 18 97 12 55 31 89 1 46 193 57 100 13 01 7 68 21 14 0 25 125 79 153 11 76 8 06 14 10 2 49 78 81 154 1 97 1 06 3 81 0 51 22 89 SUM 121 77 79 74 177 24 11 19 1079 61 Race African American 33 47 52 96 41 54 41 61 0 07 193 85 85 1 18 0 65 1 54 0 38 8 06 99 15 46 12 44 11 55 3 60 55 37 100 11 16 9 25 7 49 0 29 29 21 153 10 90 9 69 8 46 2 49 37 47 154 1 75 1 15 1 67 0 62 8 16 SUM 93 41 79 74 61 20 26 68 275 40 White Caucasian 30 47 61 74 40 07 115 00 0 10 642 13 85 10 01 4 97 22 76 0 24 125 79 99 16 68 7 92 34 78 0 31 193 57 100 1 28 0 66 2 93 0 31 16 41 153 1 87 1 10 4 00 0 51 22 89 154 11 84 4 82 18 24 2 33 78 81 SUM 103 42 61 15 191 79 5 74 1079 61 Hispanic Caucasian 7 47 34 83 26 33 35 39 4
12. Age in months was relatively normally distributed Simple linear regression found that there was no association between age in months and individual congeners or PBDE concentrations Categorical age was also not associated with specific congener or PBDE concentrations Sex and Serum PBDE Concentrations Being a female was associated with higher levels of BDE 47 t 2 77 p 0 007 and PBDE t 2 61 p 0 0109 Females had a mean BDE 47 concentration of 47 79 ng g lipid compared to 23 16 ng g lipid for males Mean PBDE concentrations were 22 82 30 ng g lipid for females and 51 44 ng g lipid for males While not significant at the 0 05 level BDE 99 and 100 approached significance with females having higher mean concentrations Race and Serum PBDE Concentrations Race was divided into four categories for statistical analysis African American Caucasian White Caucasian Hispanic and other BDE 100 serum concentrations differed between the racial groups with a F value of 6 16 and p 0 0008 Mean BDE 100 values were 8 51 3 16 1 86 and 1 41 ng g lipid for African American Caucasian White Caucasian Hispanic and other respectively Insurance Status and Serum PBDE Concentrations Insurance status was not found to be associated with serum PBDE concentrations Breastfeeding and Serum PBDE Concentrations Child history of breastfeeding was significantly associated with BDE 47 concentration Non b
13. RA 2004 Polybrominated diphenyl ethers in the environment and in people A meta analysis of concentrations Environmental Science amp Technology 38 4 945 956 Whitehead T Metayer C Buffler P Rappaport SM 2013 Estimating exposures to indoor contaminants using residential dust vol 21 pg 549 2011 J Expo Sci Environ Epidemiol 23 1 110 110 Zota AR Rudel RA Morello Frosch RA Brody JG 2008 Elevated House Dust and Serum Concentrations of PBDEs in California Unintended Consequences of Furniture Flammability Standards Environmental Science amp Technology 42 21 8158 8164 Lunder S Hovander L Athanassiadis I Bergman A 2010 Significantly Higher Polybrominated Diphenyl Ether Levels in Young US Children than in Their Mothers Environmental Science amp Technology 44 13 5256 5262 Toms LML Sjodin A Harden F Hobson P Jones R Edenfield E et al 2009 Serum Polybrominated Diphenyl Ether PBDE Levels Are Higher in Children 2 5 Years of Age than in Infants and Adults Environ Health Perspect 117 9 1461 1465 Rose M Bennett DH Bergman A Fangstrom B Pessah IN Hertz Picciotto I 2010 PBDEs in 2 5 Year Old Children from California and Associations with Diet and Indoor Environment Environmental Science amp Technology 44 7 2648 2653 Eskenazi B Fenster L Castorina R Marks AR Sjodin A Rosas LG et al 2011 A Comparison of PBDE Serum Concentrations in Mexican and Mexican American Children Living in Califor
14. Rate Nozzle Pressure Drop inches of water cfm inches of water Carpet level loop 16 5 10 Carpet other plush multilevel shag 20 8 9 Hard wood tile etc 20 8 9 To regulate the nozzle position use the height control knob on the back of the HVS3 and the nozzle level adjustment knob on the front of the nozzle See Figure 5 3 on page 15 of the HVS3 manual To regulate the flow rate use the butterfly valve on the control tube on the downstream side of the cyclone The flow is measured by the pressure drop across the cyclone The higher the flow the higher the pressure drop On level loop carpet Adjust the height of the nozzle until the bubble level is centered If the HVS3 is close to the position required but the nozzle bubble is not centered use the leveling knob on the nozzle Once it is leveled set the flow rate with the butterfly valve Check the flow rate on the flow gauge marked Q Tip the HVS3 forward for a few seconds so that the carpet will seal to the nozzle Set the flow so that the flow gauge reads 5 Read the pressure drop across the nozzle It should be approximately 10 If it is not recheck the flow and or check that the nozzle is still level If the pressure drop still does not read 10 note the gauge reading in the Technician comments section of the floor plan On other carpet plush multilevel shag Read the pressure drop across the nozzle Set the press
15. U S EPA Environmental Protection Agency 2011 Exposure Factors Handbook 2011 edition Final EPA 600 R 09 052F Washington DC U S Environmental Protection Agency Allen JG McClean MD Stapleton HM Webster TF 2008 Critical factors in assessing exposure to PBDEs via house dust Environ Int 34 8 1085 1091 Muenhor D Harrad S 2012 Within room and within building temporal and spatial variations in concentrations of polybrominated diphenyl ethers PBDEs in indoor dust Environ Int 47 23 27 Stapleton HM Kelly SM Allen JG McClean MD Webster TF 2008 Measurement of polyhrominated diphenyl ethers on hand wipes Estimating exposure from hand to mouth contact Environmental Science amp Technology 42 9 3329 3334 Virginia EJ 2012 Polybrominated Diphenyl Ether PBDE Serum Concentrations in Children Ages 15 Months to 5 Years MPH thesis Atlanta GA Emory University Rollins School of Public Health Atlanta Bernert JT Turner WE Patterson DG Needham LL 2007 Calculation of serum total lipid concentrations for the adjustment of persistent organohalogen toxicant measurements in human samples Chemosphere 68 5 824 831 La Guardia MJ Hale RC Harvey E 2006 Detailed polybrominated diphenyl ether PBDE congener composition of the widely used penta octa and deca PBDE technical flame retardant mixtures Environmental Science amp Technology 40 20 6247 6254 Quiros Alcala L Bradman A Nishioka M Harnly ME Hubbard
16. al 2012 while maternal education level is negatively associated with BDE 47 66 85 99 100 153 197 and 209 levels Rose et al 2010 If SES is truly associated with PBDE serum levels insurance status may not be the appropriate proxy measurement 32 PBDEs are lipophilic chemicals and therefore we expected them to be elevated in higher BMI groups The inverse was found with BDE 153 with concentration decreasing with increasing age adjusted BMI When tested as a categorical variable the highest BDE 153 level was found in the 25 gt 50 percentile group PBDE concentrations were lipid adjusted likely obscuring the relationship between BMI and PBDE levels In Rose et al 2009 neither BMI nor weight for age were found to be important predictors BMI is likely not an important covariate for predicting child serum PBDE levels C Dust and Handwipe PBDE Study Participation in the household dust sampling was very low and we were unable to reach the desired subset sample size of 20 This was likely due to difficulties scheduling home visits and the inherent invasiveness of having a stranger in your home Anecdotally participants were more willing to provide a used vacuum bag than having the technician vacuum Participants were asked not to vacuum three days prior to the house visit but not all complied raising problems with standardization Congener and total BDE levels in dust were extremely variable
17. any additional procedures not listed above being outside the target age range or having any preexisting condition that may affect PBDE or thyroid hormone levels Enrolled children were also excluded from further participation if they were unable to provide a full 15 mL of blood during the blood draw The total number of participants in the study was 81 11 The BEAT study nurse Christina Ryan R N CHOA obtained parental consent and enrolled the children on the day of their surgery Demographic and health information was gathered through a parental questionnaire and from the child s health records while the child was undergoing surgery The questionnaire included questions about child date of birth sex race ethnicity breastfeeding history duration at current residence parental occupation household smoking insurance status child medications height and weight and family medical history of endocrine or autoimmune diagnosis Approximately one fourth of parents indicated that they were interested in being involved in home dust and child handwipe sampling at a later date Families who resided within a 25 mile radius of Atlanta were considered for future sampling A total of 15 households were sampled for dust representing 17 child dust exposure measurements as some participants lived in the same household In addition 13 handwipes were collected at the time of dust sampling from the participating children
18. area 8 times 4 back and forth passes Move the sampler at about 0 5 m per second so it should take 2 seconds to travel 1 m Move in a straight line between the numbers on the tape After 4 back and forth passes on the first strip gradually angle over to the next 7 5 cm wide strip and repeat 4 back and forth passes Repeat until you have sampled about half the area of the template Take care not to step inside the template on areas that you have not yet sampled it is OK to step on places you have already vacuumed When you have sampled 1 square meter turn the vacuum off and check the amount of collected material in the catch bottle Don t count hair and fluff If it appears that at least 6 mm 1 4 inch of material has been obtained stop vacuuming Calculate the area sampled by noting the width of the cleaned area on the measuring tapes An area 1 m by 1 m is 1 m2 Record the area on the logsheet After vacuuming 1 m2 if less than 6 mm has been obtained mark off another 1 m2 area next to the first and vacuum it When enough material is collected record the area on the logsheet If the bottle is more than 25 full or if material in the bottle swirls near the top of the bottle when the vacuum is on take the bottle off and cap it with its own 53 cap from the plastic storage bag Secure the bottle cap with lab tape Place the bottle in its plastic storage bag and place it in the cooler with cold packs Record the
19. for different households The cause of such wide variability is not know currently although there are several studies attempting to correlate the number of PBDE treated items with dust PBDE levels in homes In household dust BDE 47 and 99 had the highest concentrations of all congeners and accounted for approximately 77 of PBDE BDE 47 and 99 have been routinely found to be major constituents of household dust However when measured BDE 209 was also a major component of dust Frederiksen et al 2009 Allen et al 2008 In the United States reported median dust concentrations for 33 BDE 209 are at least 1 mg g and 0 1 mg g for BDE 47 and 99 Whitehead et al 2013 Therefore our dust measurements may greatly underestimate PBDE without inclusion of BDE 209 During dust sample quantification significant differences between duplicates were noted for two samples 2007 005 and 2007 006 Samples were reextracted and a value between the two original values found although closer to the higher value These samples had large total sample volumes and we suspect that the dust may not have been completely homogenous The 50 mg of dust sampled was such a small proportion of the total volume that it may have resulted in a non representative sample Future study protocol should take this potential into account and ensure that samples are well mixed prior to extraction In our study dust was poorly correlated w
20. of the handle The flow Magnehelic gauge should read between 0 0 02 inches of water If the gauge reads more than 0 02 inches of water check that all connections of gauge tubing are correct and sealed tightly If all tubing is connected properly and the flow through the system still exceeds 0 02 inches of water check all gaskets and tightness of clamps catch bottle and the plug sealing the inlet tubing If the flow gauge continues to read more than 0 02 inches of water note the gauge reading in the Technician comments section of the floor plan 6 3 2b Setting Nozzle Pressure Drop section 5 2 of HVS3 manual Clean the plastic wheels with a Kimwipe and alcohol Make sure the wheels are dry before beginning sampling Remove the foil from the nozzle and place the HVS3 in the lower left corner of the sampling area Adjust the flow rate and pressure drop according to the surface wood or carpet The two factors that affect the efficiency of a sampling system are the flow rate and the pressure drop at the nozzle The pressure drop at the nozzle is a function of the flow rate and the distance between the surface and the nozzle flange Pressure drops and flows will change as you vacuum Try to keep the average values at least equal to those in Table 1 Slightly higher is better than slightly lower 51 Table 1 Target HVS3 Flow Rate and Nozzle Pressure Drop During Sampling cfm cubic feet per minute Surface Flow
21. study of 83 children 12 to 36 months of age Several problems have been identified with dust sampling Dust PBDE concentrations have been found to vary depending on the room selected for sampling probably due to differences in the furniture and electronics present Krol et al 2012 Allen et al 2008 Muenhor and Harrad 2012 Body levels of PBDE may be dependent 9 on the room the majority of time is spent in and for adults this is complicated by the fact that many work non residentially Watkins et al 2011a b Handwipes may be a more direct measure of personal exposure than dust measurements particularly among children To date four studies have measured PBDEs in handwipes and have found good agreement with dust concentrations Stapleton et al 2012 Watkins et al 2011a b Stapleton et al 2008 Handwipe concentrations were found to be better predictors of serum Penta BDE levels than dust Stapleton et al 2012 Watkins et al 2011a b D Aims and Hypotheses Aim 1 Provide needed reference values for total and congener specific blood PBDE levels in children particularly the range and variability of exposure levels Define the levels of dust and handwipe PBDEs in a subset of the participants Aim 2 Examine potential predictors of PBDE exposure levels including age sex race SES assessed by insurance status Medicaid vs private breastfeeding status and BMI Aim 3 Determine if dust or handwip
22. than 1 gram then put a piece of lab tap marking each bottle 1 2 or 3 and record the bottle number on the field log 6 1 4 Daily Maintenance of HVS3 for each vacuum used At RSPH after sampling the field technicians will Place any unused catch bottles in a designated storage area to be relabeled Feel the filter bag If it feels almost full change it and record the change on the maintenance record Decontaminate nozzles and tubing following SOP L02 Trace Cleaning of 49 vaccum and parts 6 1 5 Teflon Catch Bottle for each sample collected Weigh the dust filled Teflon catch bottle with its lid on to the nearest 0 1 gram Record the weight in the box marked After sampling full on the House Dust Sampling Field Log Enter the full bottle weight again on the House Dust and Soil Sieving Log and complete sieving tasks Decontaminate catch bottle following SOP L02 Trace Cleaning of vaccum and parts If there are clean bottles that were taken to the field but not used remove the labels and treat them like new clean bottles 6 2 Selection of Sampling Locations One floor dust sample will be collected from the room the child spends most of their time in 6 2 1 Dust sampling The field technician will ask the caregiver which room the child spends the most time in For each room sampled the technician will Remove her shoes prior to entering the room to be sampled store shoes outside
23. the room Choose a sampling area in the room that is in the main footpath or play area is accessible by the HVS3 apparatus is at least 1 meter from an outside door does not require moving furniture Areas with carpet or rug are preferred On the floor plan form for that room sketch a floor plan with measurements It does not have to be exactly to scale see example Note all significant features but especially the location of windows doors and the area sampled The location of the sampling area should be measured with the meter tape and documented on the floor plan form Choose the area to be sampled and measure the distances from two walls On the floor plan sketch the location of the area and record the sampling location and type s of floor covering 50 6 3 Sample Collection Procedure 6 3 1 General for each room to be sampled Enter the HVS3 number your initials and date onto the House Dust Sampling Field Log Place the template on the area to be sampled and secure it with tape Note the type of surface and or type of rug if relevant on the floor plan Ask the caregiver what date that area was last vacuumed or swept and enter the information on the floor plan Put on a clean pair of gloves 6 3 2 Pre Sampling Checks 6 3 2a Leak Check section 4 2 of HVS3 Manual Seal the inlet tubing by placing the back of the clipboard across the end Turn on the HVS3 with the switch at the top
24. 21 97 0 25 125 79 153 9 60 5 73 13 28 2 49 78 81 154 1 95 1 07 3 89 0 51 22 89 SUM 118 63 69 95 184 79 15 44 1079 61 Yes 48 47 40 07 32 32 30 67 0 07 149 36 85 0 86 0 64 0 83 0 38 4 16 99 12 18 8 58 11 31 0 31 55 37 100 7 55 5 98 6 74 0 24 26 27 153 10 94 6 18 12 38 1 65 69 37 154 1 44 1 06 1 27 0 63 8 16 SUM 73 04 60 18 51 14 5 74 251 99 BMI Age Adjusted Percentile 0 gt 25 16 47 42 28 27 07 38 38 0 07 129 09 85 0 78 0 65 0 61 0 39 3 00 99 11 23 8 58 10 10 0 31 32 85 100 9 78 7 62 8 89 0 31 26 27 153 16 02 10 26 17 89 2 49 69 37 154 1 48 1 06 1 36 0 63 6 22 SUM 81 57 68 57 60 84 5 74 211 61 25 gt 50 9 47 71 04 61 60 54 66 8 53 193 85 85 0 94 0 57 1 13 0 37 3 95 99 17 79 18 06 11 09 2 98 36 05 100 12 70 11 72 9 06 0 26 29 21 153 14 85 12 49 10 27 2 53 36 54 154 1 25 1 07 0 60 0 72 2 49 SUM 118 58 119 33 73 86 24 20 275 40 50 gt 75 13 47 43 26 28 64 39 03 5 47 141 61 85 1 18 0 64 1 26 0 41 4 16 99 13 74 6 89 15 06 1 87 55 37 100 5 51 3 80 6 93 0 25 24 82 153 7 45 5 69 5 12 1 65 18 28 154 1 92 1 07 2 19 0 66 8 16 SUM 73 0
25. 3 18 14 17 57 64 3 04 193 57 100 21 45 8 61 37 62 0 29 125 79 153 14 61 8 35 22 98 2 33 78 81 154 3 21 1 07 6 92 0 66 22 89 SUM 194 15 72 34 319 00 16 28 1079 61 2 3 26 47 41 01 34 82 30 41 0 10 141 61 85 0 90 0 61 0 93 0 38 4 16 99 13 16 10 07 11 87 0 31 55 37 100 6 06 5 29 5 44 0 25 24 82 153 7 67 6 06 4 72 2 46 18 28 154 1 66 1 06 1 62 0 62 8 16 SUM 70 47 58 13 49 83 5 74 251 99 3 4 18 47 51 47 33 24 50 13 0 07 193 85 85 1 23 0 65 1 82 0 37 8 06 99 12 82 9 03 10 51 3 55 36 05 100 9 99 6 00 8 62 0 30 29 21 153 9 60 5 88 8 42 1 65 28 15 154 1 45 1 06 1 32 0 68 6 22 SUM 86 55 62 92 69 04 24 60 275 40 4 5 13 47 37 25 34 01 23 64 7 68 75 76 85 0 95 0 67 0 92 0 39 3 95 99 10 22 7 41 7 75 2 22 24 43 100 6 43 5 60 6 39 0 28 17 88 153 9 20 3 79 10 14 2 78 36 54 154 1 40 1 15 0 74 0 63 3 55 SUM 65 47 59 44 41 33 15 44 126 03 5 14 47 50 20 46 24 37 18 4 54 149 36 85 0 61 0 58 0 18 0 31 1 01 99 12 85 8 78 12 65 1 46 52 13 100 9 19 7 66 8 38 0 24 26 27 153 14 58 6 38 18 58 2 53 69 37 154 0 99 0 95 0 30 0 51 1 64 SUM
26. 47 concentrations were the highest of all congeners Figure 3 while BDE 85 and 154 both had low frequency of detection in serum samples Table 4 sentin skew of the ng g medi the hi Due to its nel BDE BD wed with one e values wer lipid Partic an BDE 47 ighest media F Median Concentration ng g lipid Figure 3 M s high freque DE 47 was c individual h re between 6 cipant who w serum conce an concentra Figure 4 Se 0 0 5 0 10 0 15 0 20 0 25 0 30 0 35 0 40 0 Median Conc ency of detec chosen for fu having an ex 6 07 and 141 were five yea entrations F ations of BD erum BDE 4 centration of ction and its urther examin xtreme value 61 ng g lipi ars old or un Figure 5 Th E 99 100 7 Distributio Congener f Serum Con establishme nation Its d of 642 13 n id and the m nder two year hose under tw and 153 on of Concen ngeners ent in the lite distribution w ng g lipid Fi median value rs old had th wo years of a ntrations 47 85 99 10 15 15 1 erature as a was right igure 4 90 was 36 33 he highest age also has 7 5 9 00 53 54 19 summ extrem was 6 F PBDE s med value w me high valu 62 86 ng g li 0 5 10 15 20 25 30 35 40 45 50 Median C
27. 6 46 20 65 10 12 60 251 99 75 gt 100 32 47 39 75 38 19 26 15 4 54 149 36 85 0 92 0 65 1 34 0 31 8 06 99 11 17 8 60 9 32 1 46 52 13 100 6 23 5 85 5 01 0 24 23 54 153 6 24 4 09 4 54 2 46 22 19 154 1 26 1 06 0 68 0 51 3 55 SUM 65 57 62 01 40 14 11 19 237 33 46 8 APPENDICES A Standard Operating Procedure for BEAT Dust Collection 1 Title of Standard Operating Procedure Emory University RSPH Standard Operating Procedures F01 BEAT STUDY Collection of House Dust Samples for Pesticide Analysis Rev 1 0 2 Overview and Purpose This standard operating procedure reviews the procedures for house dust field collection for the BEAT Body Burden Study The collection method uses a high volume small surface sampler HVS3 for dust collection from bare and carpeted floors 3 Discussion The HVS3 built by CS3 of Bend Oregon has a sampling train made from aluminum For sampling pesticides Teflon gaskets and tube connections are used The HVS3 may be connected to normal household outlets House dust more than 5 m in diameter will be collected Particles larger than 150 m in diameter will be sieved out in the laboratory before analysis as larger particles are less likely to adhere to skin or to be ingested inadvertently by the age group studied Pesticides will be measured in units of ng g In addition the area sampled will be recorded so loadi
28. 62 2007 063 2007 081 ongeners in d BDE respec 47 was 405 ust by Samp g n 15 mum Max 95 02 7 62 127 25 1 23 92 13 41 10 25 293 00 2 2007 081 2007 082 2007 095 2 dust ctively BDE 26 ng g ple ximum 6012 43 840 98 10701 50 1862 65 1393 50 868 65 21679 71 BDE154 BDE153 BDE100 BDE99 BDE85 BDE47 24 E E Ha handw were childr 99 an conce statis the m 39 andwipe PB Handwipe wipe levels c collected b ren were not Handwipe nd 100 and entrations w tics for the c most prevalen of total mea Figure 8 0 50 100 150 200 250 Concentration ng handwipe BDE Distrib es were colle could be cor ecause eithe t present at t e congener d over 60 fo ere right ske congeners an nt congeners asured PBDE Congener a butions ected at the s rrelated with er the protoco the house at detection wa or all other c ewed and va nd PBDE a s in the hand E Table 7 and PBDE Handw same time as h dust levels ol had not ye the time of t as good with congeners T aried widely are presented dwipes accou Concentratio wipe Sample s household Only thirtee et been impl the visit h 100 detec Table 4 Han by sample d in Table 7 unting for ap ons in Ha
29. 63 6 565 6 BDE 99 6 55 564 7 577 7 563 6 565 6 BDE 100 6 28 564 69 577 7 563 6 565 6 BDE 153 8 02 643 62 655 5 643 6 645 5 BDE 154 7 45 643 59 655 5 643 6 645 5
30. 9 11 11 of Surgical Procedures 81 1 36 44 44 2 30 37 04 3 15 18 52 Household Smoking 70 No 56 80 Yes 14 20 Insurance Status 81 Medicaid 51 62 96 Private 30 37 04 Breastfeeding Status 81 No 33 40 74 Yes 48 59 26 BMI Age Related Percentile 70 0 gt 25 16 22 86 25 gt 50 9 12 86 50 gt 75 13 18 57 75 gt 100 32 45 71 BMI measurements for children under 2 years of age cannot be reliably compared Subjects with incomplete height and or weight data or under 2 years were not included in BMI analyses 42 Table 4 Congener Frequency of Detection in Different Matrices Sample Type BDE Frequency Serum n 81 47 89 77 85 11 11 99 98 77 100 82 72 153 66 67 154 14 81 Dust n 15 47 100 85 100 99 100 100 100 153 100 154 100 Handwipes n 13 47 100 85 86 67 99 100 100 100 153 69 23 154 61 54 43 Table 5 Stratified Serum PBDE Congener and Summed Concentrations ng g lipid N BDE Mean Median Std Dev Min Max Age years lt 2 10 47 119 49 43 05 190 02 7 45 642 13 85 2 21 0 66 4 99 0 41 16 41 99 3
31. A McKone TE et al 2011 Concentrations and loadings of polybrominated diphenyl ethers in dust from low income households in California Environ Int 37 3 592 596 6 NON PRINT SOURCES BSEF Bromine Science and Environmental Forum 2012 Legislation on BFRs in North America Available http www bsef com regulation north america accessed 15 April 2013 CDC Centers for Disease Control 2012 Children s BMI Tool for Schools Available http www cdc gov healthyweight assessing bmi childrens_bmi tool_for_schools html accessed 2 February 2012 40 7 TABLES amp FIGURES Table 1 Study Compounds Sources and Grades Compound Grade Purity Source Dichloromethane DCM HPLC Grade gt 99 8 Sigma Aldrich Hexane Hex 98 5 Sigma Aldrich Sulfuric Acid 98 08 Macron Fine ChemicalsTM Anhydrous Sodium Sulfate gt 99 0 Sigma Aldrich Toluene 92 14 Macron Fine ChemicalsTM Isopropyl Alcohol 99 5 EMD Chemicals Inc Figure 2 GC MSD PBDE Congener Chromatogam Profile by Acquisition Time BDE 47 BDE 100 BDE 99 BDE 85 BDE 154 BDE 153 41 Table 2 Subject Demographic Information n Percent Age years 81 gt 2 10 12 35 2 3 26 32 1 3 4 18 22 22 4 5 13 16 05 5 14 17 28 Sex 81 Male 46 56 79 Female 35 43 21 Race 81 African American 33 40 74 Caucasian 39 48 15 Other
32. Selective Detector MSD system Agilent Technologies Waldbronn Germany The GC consisted of a temperature stable column compartment The GC MSD was programmed and controlled using MSD ChemStation Software version E 02 02 1431 Agilent Technologies Waldbronn Germany PBDEs were analyzed by GC MSD EI 10eV Analyses were carried out using a 7890A GC coupled to a 5975C MSD Agilent Technologies Waldbronn Germany The system was fitted with a deactivated silca guard column 0 250 mm internal diameter ID Agilent Technologies Waldbronn Germany connected to a HP 5MS analytical column 15 m x 0 250 ID x 0 25 m film thickness Agilent Technologies Santa Clara CA It was operated in splitless mode 7 1442 psi 0 38703 min with an injector temperature of 250 C The helium carrier gas flow rate was 1 5 mL min and the oven temperature program was as follows 100 C 1 min 250 C 45 C min 275 C 5 C min and 315 C 45 C min held for 8 min The interface source and quadropole temperatures were set to 100 C 230 C and 150 C respectively Selective ion monitoring SIM was used during the mass spectrometric analysis of the target compounds The selected SIM are summarized in Table 9 Table 9 Congener specific GC MSD parameters Selective Ion Monitoring Congener RT MW m z BDE 47 5 47 485 8 497 7 483 7 485 7 487 7 BDE 85 7 14 564 69 577 7 5
33. Serum PBDE Concentrations 21 Race and Serum PBDE Concentrations 22 Insurance Status and Serum PBDE Concentrations 22 Breastfeeding and Serum PBDE Concentrations 22 BMI and Serum PBDE Concentrations 23 D Dust PBDE Distributions 23 E Handwipe PBDE Distributions 25 F Serum Dust Handwipe Correlations 26 4 DISCUSSION 27 A Serum PBDE Study Design 27 B Serum PBDE Distribution and Associations 28 C Dust and Handwipe PBDE Study 32 D Limitations
34. a levels of persistent organohalogens and hormone levels in adult male humans Arch Environ Health 56 2 138 143 Julander A Karlsson M Hagstrom K Ohlson CG Engwall M Bryngelsson IL et al 2005 Polybrominated diphenyl ethers plasma levels and thyroid status of workers at an electronic recycling facility Int Arch Occup Environ Health 78 7 584 592 Chevrier J Harley KG Bradman A Sjodin A Eskenazi B 2011 Prenatal Exposure to Polybrominated Diphenyl Ether Flame Retardants and Neonatal Thyroid Stimulating Hormone Levels in the CHAMACOS Study Am J Epidemiol 174 10 1166 1174 Chevrier J Harley KG Bradman A Gharbi M Sjodin A Eskenazi B 2010 Polybrominated Diphenyl Ether PBDE Flame Retardants and Thyroid Hormone during Pregnancy Environ Health Perspect 118 10 1444 1449 Roze E Meijer L Bakker A Van Braeckel K Sauer PJJ Bos AF 2009 Prenatal Exposure to Organohalogens Including Brominated Flame Retardants Influences Motor Cognitive and Behavioral Performance at School Age Environ Health Perspect 117 12 1953 1958 Herbstman JB Sjodin A Kurzon M Lederman SA Jones RS Rauh V et al 2010 Prenatal Exposure to PBDEs and Neurodevelopment Environ Health Perspect 118 5 712 719 38 Gascon M Fort M Martinez D Carsin AE Forns J Grimalt JO et al 2012 Polybrominated Diphenyl Ethers PBDEs in Breast Milk and Neuropsychological Development in Infants Environ Health Perspect 120 12 1760 1765 Hites
35. an parts in acetonitrile rinsed foil OK to use the foil from the floor of the fume hood as long as it is try and bring them to the HVS3 assembly area Put the HVS3 back together using Figure 3 1 of the HVS3 user manual as a guide Be sure the trace clean parts do not touch the floor or any other contaminated surface while you are reassembling each HVS3 Assemble only one HVS3 at a time taking care to keep the parts trace clean while not using them 6 6 Storage Prior to Sieving Dust samples should be sieved in the laboratory within a week of collecting They can be stored tightly sealed in a draw before processing If a dust sample cannot be sieved on the same day it is collected the field technician may transfer the sample to a trace clean amber glass jar for temporary storage Wipe the balance area clean with a paper towel and water if necessary Use the camel s hair brush to clean the balance pan and inside the balance Bring the filled Teflon catch bottle a trace clean 120 mL amber glass jar a piece of acetonitritile rinsed foil a pen and the House Dust and Soil Sieving Log over to the balance area Enter the sample ID UID cycle and sampling day on the Sieving Log Weigh the sample filled catch bottle with lid to the nearest 0 1 g and record the weight on the sieving log in the row labeled Mass of full Teflon bottle w lid 55 g Put on a clean pair of nitrile gloves Place a sa
36. ants like Firemaster 550 and Chlorinated Tris must be undertaken as PBDE exposures begin to decline F Conclusions The data generated by BEAT project is intended for publication in peer reviewed scientific journals For young child serum PBDE levels our study represents one of the largest and most diverse groups studies to date Additionally only one other study has investigated child serum child handwipes and household dust in the same individuals for PBDEs This study represents a much need addition to the current scientific literature The future aim of BEAT is to scale up this pilot study in order to better identify trends and associations between serum dust handwipes and thyroid hormone levels In general more studies are needed to test predictors of exposure as the current understanding is very limited Likewise handwipes appear to have potential as a new matrix but more studies and validation are needed to fully determine the variability and factors that may affect results 5 REFERENCES Birnbaum LS Hubal EAC 2006 Polybrominated diphenyl ethers A case study for using biomonitoring data to address risk assessment questions Environ Health Perspect 114 11 1770 1775 Krol S Zabiegala B Namiesnik J 2012 Determination of polybrominated diphenyl ethers in house dust using standard addition method and gas chromatography with electron capture and mass spectrometric detection J Chromatogr A 1249 201 214
37. as sampled according to a standard operating procedure Appendix A If available dust from the household vacuum was also collected for future comparison Samples were transported to the Barr Ryan laboratory the same day they were collected and were processed within 7 days of sampling Dust samples were sieved twice to a particle size of less than 250 m and stored at room temperature in a solvent cleaned amber jar until analysis Dust PBDE Extraction PBDEs were extracted from dust using accelerated solvent extraction ASE and a clean up method to remove contaminants before analysis Dust was extracted in duplicate using the ASE 350 Dionex Sunnyvale CA system The ASE was operated using the following parameters 100 C two 5 min static cycles 5 min heat time 60 rinse volume 60 sec purge time at approximately 1500 psi using an extraction solution of 10 v v DCM n hexane Cells were packed with 50 mg of dust and 20 30 mesh Ottawa Sand Fisher Scientific Fair Lawn NJ All runs included a blank sample sand only and duplicate QCHs 100 L of QCH spiked into a blank cell The extract was blown to 15 dryness at 40 C using the TurboVap and reconstituted with 5 mL of 10 DCM hexane solution Acidified silica clean up columns prepared as described in serum extraction section were preconditioned with 5 mL of hexane The sample extracts were loaded into the columns and the breakthrough collected The co
38. cannot identify individuals with high body burdens There were also problems with inconsistent congener choice there is no consensus among researchers what congeners are important to report The most commonly reported congeners were BDE 47 99 100 153 and 154 Birnbaum and Hubal 2006 Hites 2004 BDE 209 was often not measured due to difficulties in measurement methodology and lack of comparative data Lorber 2008 The study populations looked at in child serum studies were often not generalizable to the American public Lunder et al 2010 investigated a primarily higher socioeconomic status SES white Caucasian population Eskenazi et al 2011 used the Center for Health Assessment of Mothers and Children of Salinas CHAMACOS a primarily low income Hispanic population Both of these studies were extremely homogenous in terms of socioeconomic status and ethnicity Rose et al 2009 studied children born in California a state known to have high mean concentrations of PBDE compared to the rest of the United States The limitations of these studies make it difficult to generalize their findings to the larger population of American children Exposure Routes and Potential Measurement Methods In nations with low to moderate body burdens of PBDE the dominant exposure is through foodstuffs particularly dairy and meat products Lorber 2008 In highly exposed 8 nations dust is the primary pathway of expo
39. cta romines rimarily of ainly to 1 s al s 2 hexabrominated and BDE 183 octabrominated and is used in office equipment and plastic housing Deca BDE consists mainly of BDE 209 decabrominated and is used primarily in electronics Birnbaum and Hubal 2006 Frederiksen et al 2009 PBDEs are additives mixed into polymers and are not chemically linked to the polymer thus they can leach out and enter the environment Talsness 2008 Because of rising concerns about their health effects Octa and Penta mixtures were phased out by production companies in 2005 in the United States The Deca mixture is still currently in use in all states except Maine with a nationwide voluntary phase out by 2013 BSEF 2012 However even if PBDEs are no longer being produced there is the potential for exposure because of PBDEs previous widespread use persistence in the environment and continued use of pre ban products B Health Effects The health effects of PBDEs in humans are not well defined as most of the research has been limited to animal models While the toxicological mechanisms are not well understood PBDE exposure has been linked to numerous health outcomes including liver toxicity endocrine modulation altered thyroid homeostasis reproductive problems in women and men and behavioral and neurodevelopmental alterations such as hyperactivity Birnbaum and Hubal 2006 Chen et al 2011 Branc
40. d no a Lunder et al 2010 DE 47 concen was reported ween Serum Association Higher level Highest leve Higher level Concentratio levels in BM nificantly ass ant predictor e Toms et al rresponding 100 BDE3 on over time association w Eskenazi et a 2011 ntrations fro d as geometr PBDE Concen s in females els in African A s in non brea on decreases MI 25 gt 50 sociated with of exposure l 2009 rep g to increased and BDE 1 e of increase with age al Stapleton al 2012 om literature ric mean ntrations and Americans astfed s with BMI H h serum PBD e Previous st ported peak d toddling be 153 burdens d hand to m et Current st 2 ighest DE levels are tudies have ehaviors In increased mouth tudy 29 e 30 In the current study being a female was associated with higher BDE 47 and PBDE concentrations Gender was not identified as a potential predictor of PBDE exposure in any of the other studies although small sample size in the Lunder et al 2010 and CHARGE studies may have limited the statistical power to detect such an association It is unknown why female children would have higher body burdens of BDE 47 and PBDE but could be attributable to specific gender activities This is one of the first studies including a substantia
41. e PBDE concentrations are good predictors of serum PBDEs levels in children I hypothesize that lower SES breastfeeding and higher BMI will be associated with higher levels of serum PBDE 10 I also predict that handwipe PBDE levels will be more strongly correlated with serum levels of PBDE than household dust levels 2 METHODS AND MATERIALS A Study Population and Enrollment Subjects between the ages of 15 months and 6 years were recruited to be in the Brominated Flame Retardant Exposure and Thyroid Function BEAT study The study primary investigators were Lyndsey Darrow PhD Dept of Epidemiology and Dana Boyd Barr PhD Dept of Environmental Health and it was funded by NIH grant ID 5R21ES019697 02 The study age range was chosen because previous studies have shown high serum levels of PBDEs in this age group which may represent a vulnerable subpopulation Lunder et al 2010 Toms et al 2009 Eighty seven children were recruited from Children s Healthcare of Atlanta CHOA when they were admitted for a routine myringotomy adenoidectomy or tonsillectomy surgery This population was chosen for ease of blood draw Anxiety and discomfort associated with blood draws in this age group were avoided because of general anesthesia administered for the surgery The study protocol was reviewed and approved by Emory s Institutional Review Board Criteria for exclusion from the study included undergoing
42. ential mechanisms of PBDE induced thyroid hormone dysregulation are increased metabolism of T4 by induction of hepatic enzymes downregulation of thyroid hormone transport proteins or competition for transthyretin Birnbaum and Hubal 2006 Talsness 2008 Boas et al 2009 Few human studies exist regarding PBDE and thyroid function In a study of 308 adult male fishers PBDE concentration was positively associated with T4 and negatively associated with T3 and thyroid stimulating hormone TSH Hormone levels varied by 4 congener suggesting that there are congener specific mechanisms Turyk et al 2008 Similarly other epidemiological studies found that BDE 47 was associated with decreased TSH Hagmar et al 2001 and occupationally exposed workers had slight T4 elevation over time Julander et al 2005 Studies of maternal PBDE levels found negative associations with TSH and individual and sum PBDE levels but no association with neonatal TSH Chevrier et al 2011 Chevrier et al 2010 The general trend revealed by these studies is not consistent with laboratory animal data that consistently saw T4 depression and no effect on TSH It remains unclear why these differences exist The current understanding of the effects of PBDEs on human thyroid hormone levels is very limited with information on children sorely lacking despite their vulnerability Neurotoxic Effects PBDE is a known developmental neurotoxicant i
43. esponding parts Rinse all the loose parts under the faucet to remove the dirt Scrub each part including the flexible joints and gaskets with a plastic test tube brush in a warm water Liquinox solution Clean each part separately rotating it so that each internal surface is washed and brushed Rinse off the Liquinox then rinse each part 3 times with tap water 3 times with DI water and then one final time with MilliQ water Inspect each part to be sure that there is no visible trace of dust If any dust is visible wash the part again Let the parts dry in the fume hood on acetonitrile rinsed aluminum foil 54 When parts are dry rinse all sampling surfaces with acetonitrile using a Teflon squirt bottle Be sure that all surfaces that will come into contact with the sample are rinsed with acetonitrile Let the acetonitrile evaporate under the fume hood when parts are dry the vacuums can be reassembled 6 5 Reassembly at RSPH Put on a clean pair of nitrile gloves Secure a piece of trace clean aluminum foil over the mouth of the cyclone where the catch bottle attaches Use a rubber band or lab tape to be sure the foil stays on tight even when the HVS3 is being loaded unloaded into the car Secure a piece of trace clean aluminum foil over the nozzle Use a rubber band or lab tape to be sure the foil stays on tight even when the HVS3 is being loaded unloaded into the car Wrap the other trace cle
44. ge was relatively evenly distributed with two to three year olds representing the largest age group Table 2 There were slightly more male participants than females There were a total of 33 African American participants representing one of the largest numbers in a PBDE exposure study The majority of participants was breastfed as infants and came from smoke free homes Almost half of the participants were in the highest quartile 75 gt 100 for age adjusted BMI B Serum PBDE Distributions Lipid adjusted serum congener levels are presented in Table 3 Frequency of detection above LOD for the various congeners is reported in Table 4 Congener and PBDE concentrations statistics are presented stratified by age sex race insurance status breastfeeding history and age adjusted BMI in Table 5 Table 3 Serum PBDE Congener and Summed Concentrations ng g lipid n 81 BDE Mean Median Std Dev Min Max 47 54 01 36 33 76 38 0 07 642 13 85 1 09 0 64 2 03 0 31 16 41 99 15 03 9 84 22 90 0 31 193 57 100 9 43 5 99 15 00 0 24 125 79 153 10 40 5 73 12 69 1 65 78 81 154 1 65 1 06 2 66 0 51 22 89 SUM 91 61 62 86 125 32 5 74 1079 61 There was wide variation in serum BDE concentrations between subjects All congener and PBDE distributions were right skewed caused by a few subjects with high concentrations BDE
45. hi et al 2003 Boas et al 2009 The health effects of PBDEs may be congener dependent These differences in health effects are likely due to changes in biochemical properties associated with additional bromines Lower molecular weight congeners six bromines or fewer are 3 almost completely absorbed highly bio accumulate and have half lives on the order of 2 to 12 years Branchi et al 2003 Trudel et al 2011 Fully brominated deca BDE congeners are poorly absorbed and are rapidly eliminated Branchi Capone et al 2003 Endocrine Modulation PBDEs are endocrine modulators that cause disruption of thyroid hormone homeostasis Talsness 2008 Boas et al 2009 Proper development and regulation of body systems is dependent upon appropriate levels of thyroid hormones Perturbations of thyroid hormone levels may be particularly harmful during critical development phases such a neurodevelopment Birnbaum 2004 Developing fetuses and infants are especially responsive to small changes in thyroid hormone and represent an extremely vulnerable subpopulation Branchi et al 2003 In rat studies perinatal maternal and postnatal PBDE exposure reduced circulating thyroid hormones concentrations in fetuses Similarly studies in other species have consistently shown thyroxine T4 and triiodothyronine T3 reductions after exposure at dosage levels comparable to environmental human exposure Boas et al 2009 Pot
46. his current study 60 of the children were breastfed allowing for analysis of PBDE concentrations by breastfeeding history The results of this study can be more widely applied to the general population of young children than previous studies Additionally the current study utilized a novel blood draw technique that was well accepted by parents By drawing blood while the child was under general anesthesia complications associated with blood draws in young children such as discomfort were 28 avoided There was no additional time burden on parents as children were already at the hospital and participants were enrolled and sampled the same day The subjects were undergoing routine surgeries unrelated to the health outcome of interest and therefore represented a relatively health and demographically diverse subset of the general population This enrollment and sampling technique has tremendous potential for use in future studies requiring blood samples from similar age groups B Serum PBDE Distribution and Associations Serum congener and PBDE levels were highly varied between individuals Table 3 BDE 47 ranged from 0 07 to 642 13 ng g lipid and PBDE from 5 74 to 1079 61 ng g lipid Studies in adults have found there is approximately a 100 fold range in variability and children have been noted to have greater variability in PBDE serum concentrations than adults Birnbaum and Hubal 2006 Lunder et al 2010
47. ikely from difficulties in scheduling and the invasiveness of a home visit All congeners were detectable in household dust Table 4 All congeners and PBDE were right skewed with a few extreme high values causing the tailing There was wide variation in congener and total PBDE concentrations between samples Figure 7 Table 6 presents the descriptive statistics for the concentration of individual congeners and accou 99 ha PBDE in du unting for ap ad a median Figur Table 6 Dust BDE 47 85 99 100 153 154 Sum 0 5000 10000 15000 20000 25000 Concentration ng g ust BDE 99 pproximately concentratio e 7 Congen t PBDE Conge Mean 813 91 123 44 1397 19 248 55 170 91 115 16 2869 16 2007 002 2007 003 2007 004 2007 005 and 47 wer y 49 and 2 on of 579 20 ner and PBD ener and Sum Median 405 26 39 48 579 20 101 35 60 77 40 93 1221 80 2007 006 2007 012 2007 013 2007 019 Du re the most p 8 of total m ng g of dus DE Concentr mmed Concen Std Dev 6 1469 8 217 0 2631 5 457 7 343 3 213 0 5323 2007 019 2007 022 2007 041 2007 052 ust Sample prevalent co measured PB t and BDE rations in Du ntrations ng v Minim 70 25 46 1 35 56 40 64 2 2007 058 2007 0
48. important because it is only PBDE still currently produced in the United States and there is increasing evidence that it may be more biologically relevant than first thought Frederiksen et al 2009 E Future Studies Another branch of the BEAT study will be the investigation of serum thyroid hormone levels in the study population We want to determine if there are any associations between serum PBDE and thyroid hormone levels as that has been an experimentally determined health outcome for PBDE exposure Due to time constraints several proposed components of the current study were not completed In the full study dust and handwipe samples will be reanalyzed for BDE 209 Also technician collected dust samples will be compared to home vacuum dust samples to see if they are well correlated If so home vacuum bags could be an easy way to boost participation in the study A potential future study is determination of the relative contributions direct absorption dermal inhalation and ingestion to dust exposures and if there are differences in congener composition between these three exposure scenarios In the future we may try to sieve particles into fractions that would represent inhalation ingestion and dermal exposures 36 Beyond the scope of this study little is known about the exposure potential of the flame retardants replacing Penta and Octa Studies on exposure and toxicity to new flame retard
49. isil SPE cartridges were used to purify the handwipe extracts The cartridges were preconditioned with 2 mL of hexane The samples were reconstituted with 2 mL hexane and loaded onto conditioned cartridges The breakthrough was caught and the cartridge was eluted with 6 mL hexane The extract was dried in the TurboVap and reconstituted in 50 L of toluene F Dust and Handwipe PBDE Quantification A calibration curve 0 1 0 25 0 5 1 25 2 5 12 5 35 and 37 5 ng of BDE 47 85 99 100 153 and 154 mixture was prepared The calibration curve and samples were analyzed for total PBDE PBDE and six congeners BDE 47 85 99 100 153 and 154 using gas chromatography mass selective detection GC MSD in house 5975 GC MSD System Agilent Technologies GC parameters are show in Appendix B The congeners were identified by mass and chromatographic retention time as shown in Figure 2 The limits of detection derived from the standard curve were 0 10 ng for BDE 47 85 99 and 100 and 0 25 ng for BDE 153 and 154 Dust PBDE concentrations were blank subtracted and duplicates were averaged for the final concentration G Data Analysis BMI measurements were calculated using Children s BMI Group Calculator Excel system developed by the Centers for Disease Control and Prevention CDC The 17 calculator produces a BMI percentile that is adjusted by height weight sex and age measurement
50. ith PBDE and there is a clear importance of minimizing childhood exposures C Human Exposure to PBDE Global Exposure Trends The total world wide production of PBDEs in 2001 was approximately 67 400 metric tons year with the Americas consuming just over half of it Birnbaum 2004 PBDE concentrations in humans have increased by approximately 100 times during the last 30 years with North Americans having approximately 20 times more PBDE in serum compared to Europeans Hites 2004 Differences in PBDE utilization and exposure levels are likely due to stringent flammability standards in the United States and the European Union s ban of Penta and Octa in 2003 Whitehead et al 2013 Recent studies in China have suggested that Chinese exposure levels may be elevated due to the import and recycling of other nations electronic waste Frederiksen et al 2009 6 Within the U S there are wide variations in environmental and biological measures of PBDEs In California PBDE dust concentrations were 4 10 higher and serum 2 fold higher than other regions in the United States Zota et al 2008 These differences were likely attributable to California s strict furniture flammability standards that resulted in widespread use of Deca and Penta Whitehead et al 2013 Zota et al 2008 Child Serum PBDE Exposure studies have primarily used plasma serum or breast milk to measure PBDE body burden and have foc
51. ith serum levels The majority of literature has found good correlations for residential dust and serum levels Zota et al 2008 Johnson et al 2010 Stapleton et al 2012 Problems may be from non standardized sampling not all families complied with the non vacuum request Also it is well established that PBDE concentrations can vary by room so we may not have sampled the room that accounts for the majority of child exposure Watkins et al 2011a b Allen et al 2008 Muenhor and Harrad 2012 Handwipe collection was relatively easy and quick in comparison to dust collection Overall handwipes had good detection of congeners BDE 99 and 47 were the congeners most frequently detected and had the highest median concentrations in agreement with current literature Stapleton et al 2012 Watkins et al 2011a b Stapleton et al 2008 Again BDE 209 was not measured but it appears to be an important 34 contributor to handwipe PBDE levels Stapleton et al 2012 Watkins et al 2011b Stapleton et al 2008 Handwipes were correlated with serum for BDE 47 and PBDE and approached significance BDE 99 Likewise the four existing handwipe studies found that handwipes were better at predicting serum levels than dust Therefore it appears that handwipes may be a good surrogate measure for Penta exposure in children Dust and handwipe levels were not correlated which was not unexpected as the literature has shown onl
52. l African American subset so no good comparison group exists BDE 100 differed between racial groups with African American children having the highest concentrations Similarly non white children had higher BDE3 compared to white children Stapleton et al 2012 Interestingly Rose et al 2009 found that Hispanic children had higher levels of lower brominated congeners but low levels of higher brominated congeners compared to non Hispanic children In our study Hispanic children had the lowest concentrations for BDE 47 99 100 153 and PBDE of any racial group Clearly racial trends are not well defined and will need to be further elucidated by future studies It was hypothesized that being breastfed would result in a child having higher PBDE body burden as a result of maternal transfer of PBDEs via breast milk However BDE 47 was negatively associated with breastfeeding Breastfeeding status associations vary greatly in the literature For CHARGE BDE 47 and the sum of lower brominated congeners BDE 28 153 were significantly lower in breastfed children younger than 3 7 years of age but significantly higher in children older than 3 7 years of age Rose et al 2010 Lunder et al 2010 found that age of weaning and duration of exclusive breastfeeding were not associated with child serum levels 31 Review of the literature suggests that child BDE 153 exposures differ from the rest of the Penta c
53. lumns were eluted with 10 mL of hexane and the eluate added to the breakthrough Gentle negative pressure was applied to the columns to aid elution 100 L of ISTD was added and the samples were dried in the TurboVap Samples were reconstituted in 50 L of toluene E Child Handwipe Samples Handwipe Collection In the same visit as the dust collection handwipe samples were collected if the child was present A total of 13 samples were collected The child s hands were wiped with a sterile gauze pad that had been soaked in isopropyl alcohol one pad per hand The child s hands were carefully wiped up to the wrist and the two gauze wipes combined and stored in a solvent cleaned brown amber jar The samples were transferred to the Barr Ryan laboratory the same day and stored at room temperature until analysis Handwipe Extraction Handwipes were extracted following a modified protocol from Stapleton et al Stapleton et al 2008 QCL and QCH were prepared by spiking 100 L of QCL or QCH standard solutions onto two pieces of gauze soaked with isopropanol Sample and QC gauze pads were spiked with 100 L of ISTD immediately prior to extraction The 16 combined gauze right and left hand were submerged in 30 mL of DCM and sonicated for 20 minutes This extraction was repeated two times for a total extraction volume of 90 mL The extract was dried at 40 C in the TurboVap 500 mg 3 mL SupelClean ENVI Flor
54. ly contain all necessary information so that the custody of the sample can be determined at any time 7 Quality Assurance Procedures 7 1 Field and Laboratory Blanks Field blanks will be prepared by using 10ml of Hexane in the Dust collection bottle The dust residue left in the bottle will be removed with the hexane and stored in a amber jar with the regular dust samples Solvent blanks will also be analyzed with every analytical batch 7 2 Tolerance Limits Detection Limits and Sensitivity Limits 56 The tolerance limits detection limits and sensitivity limits for the method will be determined through analysis of catch bottle rinse blank solvent blanks and internal standards of analyte 8 References CS3 Inc High Volume Small Surface Sampler HVS3 Operation Manual CS3 Inc Bend OR 2001 2004 Available www cs 3 com HVS3 htm accessed 20 April 2008 Harvard University Emory University Johns Hopkins University Standard Operating Procedures for the National Human Exposure Assessment Study Maryland NHEXAS MD F04 Dust Sampling September 1995 Emory University RSPH Standard Operating Procedures F03 Collection of House Dust Samples for Pesticide Analysis CEEP Study Rev 1 0 B PBDE GC MSD Instrument Method Details The method used for analysis of BDE 47 85 99 100 153 and 154 was developed in house in the Barr Ryan laboratory Chromatographic separation was performed by Agilent 5975 Series Gas Chromatography GC Mass
55. mall surface samplers HVS3 metal and Teflon parts of sampling train trace cleaned nozzle covered in acetonitrile rinsed aluminum foil 1 trace cleaned HVS3 s will be used at each house HVS3 maintenance record kept with sampler heavy duty extension cord at least 25 feet long 3 prong outlet adaptor tools screwdriver wrench wipes Kimwipe or equivalent plastic bottle of ethanol for wiping HVS3 wheels prior to sampling spare filter bag for HVS3 Teflon catch bottles with caps trace cleaned in Ziploc bags disposable powder free gloves in Ziploc bags two sheets of aluminum foil for covering Teflon catch bottles to keep out light after sampling plastic box for toting supplies RSPH Laboratory after field sampling freezer materials and supplies for trace cleaning metal and Teflon HVS3 parts Sample Tracking and Paperwork Field Packet for household field log floor plan chain of custody form Field Manual SOPs clipboard pens ballpoint 2 black or blue for field log floor plan 6 Procedure 6 1 Preparation for Collection 6 1 1 Assembly Calibration and Maintenance of HVS3 The field technicians are responsible for assembly calibration and maintenance of the HVS3 They will record assembly calibration and filter bag changes on the maintenance record sheet that is kept for each HVS3 48 Assembly The HVS3 will be assembled and tested no more than 2 weeks prior to the beginning of study sampling For assembly instructions see
56. mple ID label on the amber glass jar and an identical label on the lid a handwritten label on lab tape is OK just be sure the ID number is correct Zero the balance Weigh the empty amber glass jar with its lid on to the nearest 0 1 g and record the weight on the sieving log in the row labeled Mass of empty amber glass jar w lid g Remove the lid from the amber glass jar and set it aside on the foil taking care to not get any lab dust or dirt on it Gently tap the dust from the catch bottle into the amber glass jar making sure you get as much sample as possible into the jar Some residue will remain on the walls of the catch bottle That is OK Screw the lid tightly back on the amber glass jar weigh it to the nearest 0 1 g and record the weight on the sieving log in the row labeled Mass of full amber glass jar w lid g Write is the Sample was stored before sieving Trace clean the Teflon catch bottle and lid following the procedures outlined in Section 6 4 Put the Sieving Log back into the binder labeled BEAT STUDY 6 7 Sample Tracking The ID number will allow tracking of each sample A data base management system will ensure knowledge of the status and location of any sample at any time including retrospectively The chain of custody form will accompany samples through all transactions Anyone who receives transfers or ships samples will sign and date the form and keep a photocopy It must clear
57. n mice Gestational and neonatal low doses of PBDE caused irreversible changes in adult mouse brain function mice displayed hyperactivity as adults that worsened with age Talsness 2008 BDE 99 in particular altered the cholinergic system and caused deficits in learning and memory in mice Human studies investigating neurodevelopmental effects of PBDEs have observed adverse neurodevelopmental effects in 4 6 year olds prenatally exposed Roze et al 2009 Herbstman et al 2010 Postnatal BDE 47 exposure was associated with higher risk of ADHD symptoms and decreased mental development Gascon et al 2012 Mechanisms underlying this neurotoxicity have not been fully elucidated but there is evidence of thyroid hormone mediated effect Thyroid hormone is an integral 5 component of brain development and alterations in normal hormone levels can cause distinct changes in neuro behavioral development Relatively small changes in maternal T4 negatively impact intelligence and psychomotor skills in children Branchi et al 2003 As discussed above thyroid hormone regulation is a likely target of PBDE toxicity There is a critical window of sensitivity to PBDE in mice that corresponds to the period of rapid brain growth Talsness 2008 Fetal exposure and infant exposures via breastfeeding would occur during this developmental stage Therefore protection of pregnant women and young children is a priority when dealing w
58. nd dust sampli en handwipe lemented or ction rate fo ndwipe PBD Figure 8 D BDE 99 an pproximately dwipes by Sa B B B B B B 2 ng so e samples some r BDE 47 DE Descriptive nd 47 were y 43 and ample DE154 DE153 DE100 DE99 DE85 DE47 25 26 Table 7 Handwipe PBDE Congener and Summed Concentrations ng handwipe n 13 BDE Mean Median Std Dev Minimum Maximum 47 14 31 6 46 22 40 1 44 84 27 85 1 17 0 42 1 89 0 07 6 67 99 15 44 5 01 25 34 1 48 95 20 100 2 97 0 97 4 98 0 23 18 73 153 1 43 0 63 2 11 0 18 7 95 154 1 04 0 35 1 70 0 18 6 39 Sum 36 27 13 46 58 35 3 14 219 22 F Serum Dust Handwipe Correlations All serum dust and handwipe PBDE data were non normal Therefore log10 transformed data were used for all correlation tests While there were 15 dust samples there were 17 children with dust PBDE data available for comparison because some children lived in same household Serum and dust individual congeners and PBDE were not correlated Dust and handwipes PBDE levels were also not correlated at the 0 05 level However BDE 153 approaches significance r 0 50 p 0 0818 Serum and handwipes were correlated for BDE 47 and PBDE For BDE 47 the Pearson s correlation coefficient r is equal to 0 652 and p is 0 0158 For PBDE
59. ngs can also be expressed as mass per square meter 4 Personnel Responsibilities Sampler Preparation and Maintenance Teflon catch bottles and all metal parts of the HVS3 will be cleaned at RSPH according to SOP L01 Trace cleaning Vacuum and collection bottle rev 01 Sampler preparation is the responsibility of the field technicians The field technicians are also responsible for preparing Field Packets and equipment box Sample Collection The field technicians are responsible for all aspects of sample collection Also responsible for contacting and setting appointments Storage Immediate storage of the sample upon return to RSPH is the responsibility of the field technicians Custody will be turned over to the lab technician s for extraction and or long term storage Sieving and Division The field technicians are responsible for sieving and division of samples prior to extraction see SOP L02 Beat Sieving and Division of Dust Samples rev 1 5 Required Equipment and Reagents 47 RSPH Laboratory before field sampling 2 catch bottles 1 for samples 1 extra trace cleaned Teflon FEP wide mouth bottles 8 oz 250 mL capacity pre weighed with weight recorded on House Dust Sampling Field Log attached lab tape plastic bags sealable 1 quart about 6 x 10 to hold catch bottle Field Sampling tape measure approximately 25 feet long 8 m Craftsman 1 wide recommended easy peel off laboratory tape lab tape 1 high volume s
60. nia Environ Health Perspect 119 10 1442 1448 Johnson Restrepo B Kannan K 2009 An assessment of sources and pathways of human exposure to polybrominated diphenyl ethers in the United States Chemosphere 76 4 542 548 Lorber M 2008 Exposure of Americans to polybrominated diphenyl ethers J Expo Sci Environ Epidemiol 18 1 2 19 Johnson PI Stapleton HM Slodin A Meeker JD 2010 Relationships between Polybrominated Diphenyl Ether Concentrations in House Dust and Serum Environmental Science amp Technology 44 14 5627 5632 Wu N Herrmann T Paepke O Tickner J Hale R Harvey E et al 2007 Human exposure to PBDEs Associations of PBDE body burdens with food consumption and house dust concentrations Environmental Science amp Technology 41 5 1584 1589 Stapleton HM Eagle S Sjodin A Webster TF 2012 Serum PBDEs in a North Carolina Toddler Cohort Associations with Handwipes House Dust and Socioeconomic Variables Environ Health Perspect 120 7 1049 1054 39 Watkins DJ McClean MD Fraser AJ Weinberg J Stapleton HM Sj din A et al 2011a Impact of Dust from Multiple Microenvironments and Diet on PentaBDE Body Burden Environmental Science amp Technology 46 2 1192 1200 Watkins DJ McClean MD Fraser AJ Weinberg J Stapleton HM Sj din A et al 2011b Exposure to PBDEs in the Office Environment Evaluating the Relationships Between Dust Handwipes and Serum Environ Health Perspect 119 9 1247 1252
61. number of bottles used on the logsheet Install a new bottle and continue sampling When you have enough dust turn off the HVS3 Tap on the U tube and cyclone vigorously to dislodge any particles trapped in the sampling train Unscrew the catch bottle Holding the catch bottle under the cyclone gently tap the threads on the cyclone to be sure any particles trapped in the threads are dislodged into the catch bottle Gently tap the catch bottle a few times to allow particles to settle and cap it with its own cap from the plastic storage bag Screw the cap on tightly and secure it with lab tape Wrap the bottle tightly with foil to protect it from light Place the bottle in its plastic Ziploc and place it in the cooler with cold packs Remove the gloves and discard them in the trash bag Finish the floor plan sketch if necessary and fill in any missing information on the floor plan form Tell the caregiver you are finished sampling that room and thank her him for her his help 6 4 Decontamination and Reassembly at RSPH Unfasten the clamps and disassemble each HVS3 from the nozzle to the control valve tube see Figure 3 1 of HVS3 manual You do not need to clean the control valve tube or anything between it and the vacuum bag You do not need to trace clean the metal clamps Wipe each wheel with a Kimwipe to remove any dirt or dust Separate the Teflon joints from the metal parts and the gaskets from their corr
62. oncentration ng g lipid Figure 5 Dis erum concen as driven mo ue at 1079 6 ipid with 90 Figure 6 Se 47 8 stribution of ntrations foll ostly by BDE 61 ng g lipid 0 of values erum PBDE 85 99 Serum Cong lowed a patt E 47 The d Figure 6 T s falling betw E Distributio 100 BDE geners by A tern similar t data were rig The median ween 15 44 a on of Concen 153 ge Group to BDE 47 a ght skewed w PBDE con and 236 91 n ntrations 154 2 as the with one ncentration ng g lipid lt 2 yrs 2 yrs 3 yrs 4 yrs 5 yrs 20 21 C Serum PBDE Associations Statistical Analysis Congener specific and PBDE associations with age sex race insurance status breastfeeding status and age adjusted BMI were tested Age and BMI were tested both as continuous and categorical variables Age was categorized by years of age and BMI data were divided into quartiles to produce categorical variables Continuous variables age and BMI were tested for associations with serum PBDE concentrations using simple linear regression One way ANOVA tests were performed for categorical variables with more than two groups age BMI and race Student s T tests were used to test for associations between serum concentrations and sex breastfeeding history and insurance status Age and Serum PBDE Concentrations
63. ongeners BDE 47 99 100 by pathway Duration of breast feeding was a strong predictor of BDE 153 but not sum BDE 47 99 and 100 Stapleton et al 2012 In breastfed children BDE 153 was positively associated with age conversely in non breastfed children BDE 153 was negatively associated with age Rose et al 2010 Also BDE 153 comprised a larger portion of BDE 28 153 in breastfed children than non breastfed children Rose et al 2010 BDE 153 is enriched in maternal adipose tissue compared to other Penta congeners and is found in greater levels in breast milk despite only being 5 8 of the commercial mixture La Guardia et al 2006 Taken together the data suggest that the primary exposure to BDE 153 in children is via breast milk and to BDE 47 99 and 100 via some other pathway likely dust However we did not observe any association between serum BDE 153 and breastfeeding history It has been posited that low income individuals may have greater PBDE exposure because they are more likely to have older furniture that was treated with Penta and Octa before the ban Zota et al 2008 Quiros Alcala et al 2011 Therefore we hypothesized that lower SES would be associated with higher PBDE body burdens In our study we used insurance status private vs Medicaid as a proxy for SES and found no associations However higher paternal education level was strongly and inversely related to BDE3 Stapleton et
64. ool of Public Health of Emory University in partial fulfillment of the requirements for the degree of Master of Public Health in Environmental Health 2013 Abstract Predicting Body Burden of Polybrominated Diphenyl Ethers in Children Aged 15 Months to 5 Years Using Household Dust and Handwipe Levels and Selected Demographic Variables By Grace Evelyn Lee Polybrominated diphenyl ethers PBDEs are a class of brominated flame retardants that are ubiquitous in the environment and in human biological samples Despite bans on two of the three major commercial mixtures of PBDEs the United States has the highest serum concentrations in the world due to historically high use PBDEs are known endocrine modulators and have been linked to numerous neurodevelopmental and behavioral disabilities Studies have suggested that children may be particularly sensitive to PBDE exposures Simultaneously they may have serum concentrations up to 10 fold higher than adults Few studies have looked at individual child serum levels or attempted to correlate them with environmental matrices The aim of this study was to determine child serum handwipe and household dust levels of PBDEs for a group of demographically diverse children Blood samples were obtained from 81 children enrolled at the Children s Hospital of Atlanta CHOA while undergoing a routine surgery At a later date a subset of participants had household dust n 15 and handwipes n 13 collected Serum d
65. rabro urethane foam TION minated diphe ntly used in structure sim nited States in mentally pers E congeners two aromati Hubal 2006 total numbe nyl ethers T F jor commerc ly pentabrom iphenylether m and Huba ominated an m in furnitur enyl ethers consumer pr milar to polyc n 1978 Like sistent bioac exist differi ic rings and The congen er of bromin The general Figure 1 PBD cial mixtures modiphenyl r Deca so n al 2006 Krol nd BDE 99 re Octa BD PBDEs are roducts such chlorinated b e PCBs PBD ccumulate a ing in structu are numbere ners are divid nes that they structure is DE General s of PBDEs ether Penta named for th l et al 2012 pentabromin DE is compos a class of br h as electron biphenyls P DEs are pers and biomagn ture by the nu ed according ded into 10 h contain mo shown in Fig Structure have been u a octabromo he average n Penta BDE nated and is sed mainly o rominated fl nics and texti PCBs which sistent organ nify Birnbau number and l g to the IUPA homologous ono to gure 1 used in the U odiphenyleth number of br E consists pr s applied ma of BDE 153 lame iles PBDEs h were nic pollutants um and Huba location of AC system s groups United States her O
66. reastfed children had higher mean BDE 47 concentrations than breastfed children t 2 02 p 0 0465 Mean BDE 47 was 43 66 ng g lipid for non breastfed children and 25 39 ng g lipid for breastfed children 23 BMI and Serum PBDE Concentrations Age adjusted BMI percentile was normally distributed and did not need to be log adjusted When tested as a continuous variable there was a significant negative association between BDE 153 and BMI percentile at the 0 05 level The R2 for the association was 0 0911 with a p value of 0 0111 For every increase in BMI percentile there is a 1 007 ng g lipid decrease in BDE 153 A similar trend was observed when BMI was tested as a categorical variable BDE 153 concentrations differed between BMI quartiles with a F value of 3 87 and a p value of 0 0130 BDE 153 mean concentrations were 8 51 11 75 6 03 and 5 13 ng g lipid for the 0 gt 25 25 gt 50 50 gt 75 and 75 gt 100 BMI groups respectively D Dust PBDE Distributions A convenience sample of eligible children was selected for household dust and handwipe sampling The desired sample size was 20 but there was difficulty in obtaining permission for home visits To boost participation all participants families within a 25 mile radius of Emory were contacted about home sampling The final sample size for household dust was 15 Refusal for participation in the dust sampling portion of the study was extremely high l
67. roject would not have been possible I would also like to thank Dr Lyndsey Darrow for allowing me to work on her BEAT project and her invaluable help with data processing I am greatly indebted to the Barr Ryan laboratory staff especially Dr Parinya Panuwet and Priya D Souza This thesis would not exist if it were not for them They spent countless hours helping me process samples troubleshoot problems and lending their expertise I am forever grateful that they gave their time to teach me some of their skills and knowledge Table of Contents 1 INTRODUCTION 1 A Background 1 B Health Effects 2 Endocrine Modulation 3 Neurotoxic Effects 4 C Human Exposure to PBDE 5 Global Exposure Trends
68. s CDC 2012 Body fat composition varies by gender and age in children The age adjusted BMI percentile allows for comparison of children regardless of age and gender BMI cannot be accurately calculated for children less than two years old so those individuals were removed for BMI analysis Statistical analyses were performed using Microsoft Excel 2011 Software Version 14 3 2 and SAS Statistical Software Version 9 3 Serum and handwipe measurements below the limit of detection LOD were computed by dividing the congener specific LOD by the square root of two All data were log10 transformed to correct for skewedness Log transformation produced more normal distributions for all congeners and PBDE therefore all statistical tests were performed using the log transformed serum data One way ANOVA tests Student s T tests and simple linear regression analyses were used to investigate associations between serum PBDE concentrations and covariates of interest Correlation analyses were performed to determine associations between serum dust serum handwipe and dust handwipe congener and total PBDE levels 3 RESULTS A Demographic Data The BEAT study had high enrollment with a refusal rate of only 6 3 for participation in the blood draw The study recruited a total of 81 eligible participants that were all included in analysis Subject demographic information is presented in Table 2 18 Subject a
69. section 3 4 of the HVS3 Manual Calibration A full flow calibration will be conducted no more than two weeks prior to the beginning of study sampling For directions see the HVS3 Manual section 3 3 Zero the gauge in the position in which it will be used Filter bag Bags will be changed immediately prior to beginning of study sampling and the changed logged in the maintenance records attached Later in the study if the flow rate cannot be adjusted for sampling change the bag and record the change on the maintenance record 6 1 2 Reminder to Respondent The field technicians will contact the subject and remind her him about the sampling appointment at least 3 days ahead of the appointment Include instructions that respondent refrain from vacuuming for at least three days prior to sampling 6 1 3 Identification Labels The field technicians will Hand write ID labels for each sample to be collected from a particular house that day For each sample to be collected record ID on the floor plan sheet Assemble the Field Packet for the household The Field Packet should include one floor plan sheet for each sample to be collected and this SOP Weigh the trace cleaned empty Teflon catch bottle with the lid screwed on to the nearest 0 1 gram Record the weight in the box marked Before sampling empty on the House Dust Sampling Field Log If the weights of the 3 empty Teflon bottles going to the same house differ by more
70. sure and can account for about 82 total PBDE intake Trudel et al 2011 Lorber 2008 In the United States household dust levels have been found to be good estimators of exposure Johnson et al 2010 Wu et al 2007 Stapleton et al 2012 Watkins et al 2011a b Dust sample collection is less invasive than biological sampling making it an appealing alternative matrix PBDEs volatilize from the product and adsorb onto dust Dust can then enter the body via inhalation inadvertent ingestion from hand to mouth contact or direct absorption through the skin Whitehead et al 2013 Very little data currently exists about the relative importance of each of these routes to total exposure levels but it is estimated that ingestion is responsible for 80 and dermal 10 30 of total PBDE exposure Frederiksen et al 2009 For young children approximately one to five years old dust exposure is increased by hand to mouth behaviors and proximity to dust covered surfaces Daily intakes of dust for small children 1 4 years have been estimated to be 100 200 mg d while adult intake is estimated around 50 mg d U S EPA 2011 Therefore PBDE dust measurements may be of particular use in determining child exposure levels Currently only one study has attempted to link child serum PBDE levels and household dust levels Stapleton et al 2012 found that serum Penta levels were associated with house dust Penta levels in a
71. th the sample breakthrough in the TurboVap and the samples brought to total dryness at 30 C at 15 psi Samples were reconstituted with 50 L of toluene for analysis GC MS MS instrument parameters for serum PBDEs were developed by Virginia 2012 As PBDEs are lipophilic serum PBDE levels were lipid adjusted Total lipid TL content of each sample was calculated using the formula TL 2 27 TC TG 62 3 mg dL where TC is total cholesterol and TG is total triglyceride Bernert et al 2007 Serum triglyceride content was measured using BioVision Triglyceride Quantification Assay Kit BioVision Research Products Mountain View CA and serum cholesterol content was measured using Cayman Cholesterol Assay Kit Cayman Chemical Company Ann Arbor MI according to manufacturer instructions Serum PBDE levels are reported in ng of PBDE per gram of lipid ng g 14 D Household Dust Samples Dust Sample Collection 15 households agreed to allow a field technician enter their homes and vacuum to collect a dust sample When arranging a sampling time participants were asked to refrain from vacuuming so there would be enough dust volume to collect Parents identified the room that the participant spent the most time in and this room was selected for sampling Using a solvent cleaned high volume small surface sampler HVS3 vacuum CS3 Inc Bend OR and solvent cleaned Teflon catch bottle a 1 m3 square of floor w
72. ure drop at approximately 9 on the nozzle gauge by using the height adjustment knob and the level knob to keep the nozzle level Check the flow rate Use the butterfly valve to set it at about 8 Check the pressure drop across the nozzle again It will have changed from 9 because of the increased flow rate which increased the pressure 52 drop across the nozzle and vice versa Set the nozzle pressure drop to 9 again using the height adjustment You will probably need to make a few small adjustments three or four times until it is set right It need not be exact The flow rate should be between 8 and 9 and the nozzle pressure drop should be between 9 and 9 5 If the pressure drop still does not read 9 9 5 note the gauge reading in the Technician comments section of the floor plan If the carpet is thin and the vacuum sucks it up open the butterfly valve and readjust If the flow rate cannot be adjusted for sampling change the filter bag Record the change on the maintenance record sheet Check that the lever at the bottom is in the notch next to the lowest so that the handle is at a 45 angle with the floor With the handle at this angle and a firm downward pressure the HVS3 is much less likely to nosedive 6 3 3 Sample Collection Begin sampling by moving the nozzle forward and back along the left edge of the area marked by the template covering an area 7 5 cm 3 wide and 1 m long Vacuum this
73. used on adults Frederiksen et al 2009 Studies of PBDE levels in children have been extremely limited due to difficulties associated with collecting blood samples However the toxicological data suggests that children may be more sensitive to PBDE exposures Simultaneously children aged one to five years appear to be more 2 to 10 fold more exposed to PBDEs than adults Lunder et al 2010 Toms et al 2009 Rose et al 2010 Eskenazi et al 2011 Peak concentrations of PBDEs in children occur around 2 to 3 years of age as a result of increased hand to mouth behavior and dust exposure discussed more below Lunder et al 2010 Toms et al 2009 Infants lt 1 years old also have high PBDE exposure but their exposure comes almost exclusively from breastmilk Johnson Restrepo and Kannan 2009 The results produced by child serum PBDE studies in the U S have been severely limited by sample size pooled analyses congener choice and unrepresentative study populations Only recently have studies moved away from using pooled serum samples 7 and started using individual samples This is problematic because it has been well documented that serum PBDE concentrations may vary greatly with 5 of the population having concentrations of PBDE at least 10 times the mean and 1 as much as 50 times the mean Birnbaum and Hubal 2006 Pooled serum samples therefore may not be a good representation of average exposures and
74. ust and handwipes were extracted and the concentrations of six congeners BDE 47 85 99 100 153 154 and PBDE determined in house by GC MSD analysis BDE 47 and 99 were dominant congeners in all three matrices In serum significant associations were found between sex and BDE 47 and PBDE race and BDE 100 breastfeeding history and BDE 47 and BMI and BDE 153 Handwipe and serum were correlated for BDE 47 and PBDE suggesting that handwipes may be a good personal exposure measure for the Penta DBE mixture To date only one other study has investigated child serum child handwipes and household dust in the same individuals for PBDEs Additionally this is one of the largest and most diverse groups studied in this age demographic for PBDE exposures Predicting Body Burden of Polybrominated Diphenyl Ethers in Children Aged 15 Months to 5 Years Using Household Dust and Handwipe Levels and Selected Demographic Variables By Grace Evelyn Lee B A Kenyon College 2009 Thesis Committee Chair Dana Boyd Barr Ph D A thesis submitted to the Faculty of the Rollins School of Public Health of Emory University in partial fulfillment of the requirements for the degree of Master of Public Health in Environmental Health 2013 Acknowledgements Many thanks to my advisor Dr Dana Boyd Barr It was her engaging lectures that first introduced me to the fascinating world of exposure science Without her knowledge enthusiasm and support this p
75. y weak correlations Handwipes are a more integrative measure of exposure as it represents all the locations a child has recently been whereas dust only provides information about one particular microenvironment However a potential issue with handwipes is that handwashing immediately prior to sampling may reduce handwipe levels so they are no longer representative of body burden Watkins et al 2011b It was noted that one child had washed his hands before sampling and we are unsure what effect this had on his handwipe levels Despite this problem handwipe sampling has the advantage of being faster easier and easier to standardize than dust collection D Limitations While sample size for our study was much larger than those previously studied power was still limited when the group was broken down into strata Likewise the sample size for the dust and handwipes was very small We did not have appropriate statistical power and we may have missed some correlations Dust sample size was intended to be larger but there was great difficulty gaining subject participation It is unclear what can be done to boost participation in dust sampling 35 Another major limitation of this study was that BDE 209 was not measured despite evidence that it is an important contributor to PBDE As BDE 209 is the principle component of the Deca commercial mixture we have no data on Deca exposure Knowing Deca exposure is

Distribution Agreement In presenting this thesis

Contents

Download Pdf Manuals

Related Search

Related Contents