Vos JG †
† National Institute of Public Health and the Environment, Bilthoven,
The Netherlands
From an environmental point of view, an increasingly important group of organohalogen compounds are the brominated flame retardants (BFRs), that are widely used in polymers and textiles, and applied in construction materials, furniture and electronic equipments. BFRs with the highest production volume are the polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBP-A) and hexabromocyclododecane (HBCD). Because of their persistence and low biodegradation profile, several of the PBDE congeners accumulate in biota and are widely found in the aquatic food chain. Their levels in the environment and in humans have increased during the last decades, in contrast to, e.g., PCBs and DDT. Humans may be exposed to PBDEs mainly through consumption of fatty food from animal origin, e.g., fish, but exposure through skin contact with textiles protected with flame retardants or through inhalation of BFRs volatilized from electronic and electric equipment may also occur. PBDEs exhibit a variety of biological effects depending on the bromine substitution pattern. PBDEs are potential endocrine disrupters, based on shared toxicity, including developmental toxicity, with the structurally related PCBs, PCDFs and PCDDs. The potency of TBBP-A to interact with thyroid hormone homeostasis is indicated from in vitro studies in which the compound competes with thyroxin (T4) for binding to transthyretin. So far, the toxicological profile of many BFRs is too incomplete and insufficient to perform an adequate risk assessment and further information is required regarding the potential for endocrine disruption of these compounds that are of increasing environmental concern
|
|
|
| Go back | |
| This site is maintained by JaDes |
|