Health Concerns Overview

Transcription

1 F L A M E R E T A R D A N T S V. Health Cocers Overview Edocrie-disruptig chemicals ca mimic estroges (female sex hormoes), adroges (male sex hormoes), ad thyroid hormoes, which ca cotribute to hormoally iduced cacers, icludig breast cacer. Edocrie Disruptio Edocrie-disruptig chemicals (EDCs) ca mimic estroges (female sex hormoes), adroges (male sex hormoes), ad thyroid hormoes, which ca cotribute to hormoally iduced cacers, icludig breast cacer. They ca also adversely affect ormal developmet, reproductio ad eurologic fuctio. 167 Recet huma studies demostrate a declie i seme quality ad male testosteroe levels. Studies have show a icrease i rates of develop metal aomalies of the reproductive tract, testicular cacer, thyroid cacer, cogeital hypothyroidism, ad eurologic developmet disorders. 168 Studies i aimals were the first to suggest that flame-retardats could affect the edocrie system. Altered male hormoes ad 60

2 T H E C A S E F O R P O L I C Y C H A N G E reduced sperm couts were foud i aimals exposed to PBDEs, as well as malfuctios of the thyroid hormoe system. 169 Studies i humas have bee eve more alarmig. PBDE levels i materal ad cord blood tissues have bee associated with the absece of oe or both testes i male ifats, lower birth weights, ad eurodevelopmetal ad behavior problems i childre, raisig cocers about exposure of wome to PBDEs durig pregacy. 170 Cocers that PBDEs disrupt the edocrie system led the Natioal Istitute of Evirometal Health Scieces (NIEHS) to fud studies o their health effects i people. A study of a predomiatly Mexica immigrat populatio was the first to report that higher PBDE cocetratios i wome s blood were associated with a loger time tryig to get pregat. 171 A more recet NIEHS-fuded study implicated Firemaster 550 as a edocrie disruptor ad obesoge at evirometally relevat levels. 172 The NIEHS is curretly cotiuig a multigeeratioal edocrie disruptio study usig the Michiga PBB cohort, with a focus o the offsprig of those exposed who show evidece of edocrie disruptio. 173 Sos of highly exposed wome experieced a icreased risk of geitouriary coditios ad slower growth ad pubertal developmet, ad highly exposed girls had a earlier age at mearche ad a icreased risk of miscarriages. 174 PBDE levels i materal ad cord blood tissues have bee associated with the absece of oe or both testes i male ifats, lower birth weights, ad eurodevelopmetal ad behavior problems i childre, raisig cocers about exposure of wome to PBDEs durig pregacy. PBDEs ad TBBPA have chemical structures similar to thyroid hormoes that are essetial for fetal developmet. TBBPA exhibits 61

3 F L A M E R E T A R D A N T S thyroid hormoe activity i laboratory studies ad has estrogeic activity i experimetal aimals. TBBPA-exposed aimals had decreased thyroid hormoes ad icreased weight of testes ad pituitary i male offsprig. 175 Oe metabolite produced by TBBPA is BPA, a kow estroge mimic. 176 Newer studies suggest that HBCD ad Firemaster 550 also have the potetial to disrupt the edocrie system. 177 Orgaophosphate (OP) flame-retardats have bee poorly studied; however, there is evidece suggestig adverse edocrie ad reproductive effects. 178 Most of the flameretardats i use today have ot bee tested for their potetial to cause cacer. At a U.S. ifertility cliic, a small study suggested that exposure to TDCPP ad TPP from house dust could be associated with altered hormoe levels ad decreased seme quality i me. 179 Several aimal studies o OP flame-retardats show reproductive health effects, raisig cocers about ukow huma health effects associated with exposure to these chemicals. 180 Cacer Most of the flame-retardats i use today have ot bee tested for their potetial to cause cacer. Two structurally similar flameretardats, TCEP ad TDBPP, have bee idetified as causig cacer uder Califoria s Propositio 65, ad are listed as kow to cause cacer. TCEP has bee detected i idoor air samples ad i dust i homes, offices, schools, ad cars. 181 TDCPP is also a probable huma carcioge, based o sufficiet evidece i aimals. These chemicals have bee detected i dust idoors, where they migrate to the surface ad are released from cosumer products. 62

4 T H E C A S E F O R P O L I C Y C H A N G E I the oly study available o TDBPP i house dust, it was detected i 75 percet of homes tested. 182 TDCPP was detected i 96 percet of house dust samples collected i the Bosto area. 183 EPA cosiders DecaBDE to have suggestive evidece of carciogeic potetial based o aimal studies. 184 Brai Fuctio Orgaohaloge compouds such as DecaBDE, TBBPA, ad HBCD are kow to have eurotoxic effects o the developig brai. I pregat wome, these compouds cross the placeta to the fetus. Durig critical periods of fetal growth ad develop met, orgaohaloge compouds may iterfere with developmetal processes i the brai. 185 Orgaohaloge compouds such as DecaBDE, TBBPA, ad HBCD are kow to have eurotoxic effects o the developig brai. The chemical structures of orgaophosphate (OP) flame-retardats are similar to those of OP isecticides, which were desiged to be 63

5 F L A M E R E T A R D A N T S The most recet ad largest study o childhood exposure to PBDEs showed a associatio betwee preatal ad childhood exposures ad deficits i attetio, fie motor coordiatio, ad cogitio i school-aged childre. eurotoxic to isects, ad may are capable of ihibitig critical ezymes i humas ecessary for eurological growth ad fuctio. Orgaophosphate (OP) flame-retardats (TCEP, TCPP, ad TDBPP) are toxic via several differet biochemical pathways, icreasig the cocer for eurotoxicity. 186 Over the last decade, aimal ad laboratory studies suggest that bromiated flame-retardats (BFRs) are potetially eurotoxic. 187 I 2009, the first study assessed their eurodevelopmetal toxicity i humas, demostratig that developmetal deficits i youg childre were associated with preatal exposures. 188 Several small studies have subsequetly associated cocetratios of several PBDE cogeers i umbilical cord blood of ewbors with eurodevelopmetal effects i early childhood

6 T H E C A S E F O R P O L I C Y C H A N G E The most recet ad largest study o childhood exposure to PBDEs showed a associatio betwee preatal ad childhood exposures ad deficits i attetio, fie motor coordiatio, ad cogitio i school-aged childre. 190 A large Califoria study ivestigated the eurobehavioral effects of bromiated flame-retardats i humas ad foud a associatio betwee low-level PBDE exposure ad chages i motor fuctio ad serum levels of thyroid hormoes. 191 Fidigs from a 2013 NIEHS-fuded study have also idetified PBDEs as a possible risk factor for Parkiso s disease ad eurodegeerative diseases. The authors of the study ote the importace of additioal research o PBDEs as a potetial risk factor for Parkiso s disease ad other eurological disorders. 192 Potetial Health Risks of Commo Flame-Retardats TABLE 7 Reproductive Edocrie Disruptio Brai Fuctio Cacer Developmetal PetaBDE OctaBDE DecaBDE TBBPA HBCD FM 550 NS NS NS NS TDBPP NS NS TDCPP NS NS TCPP NS NS NS TCEP NS TCP NS NS TBEP NS NS NS NS = Not studied 65