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Brominated flame retardants (BFRs) are synthetic organobromide compounds which inhibit ignition and combustion
processes. Because of their immense ability to retard fire and save life and property, they have been
extensively used in many products such as TVs, computers, foam, plastics etc. The five major classes of BFRs
are tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), pentabromodiphenyl ether, octabromodiphenyl
ether, and decabromodiphenyl ether. The last three are also commonly called PBDEs. BDE-85
and BDE-209 are the two prominent congeners of PBDEs and this study reports the adverse effects of these
congeners in rodents. Exposure of rat sciatic nerves to 5 μg/mL and 20 μg/mL of BDE-85 and BDE-209 respectively
lead to significant, concentration dependent reduction in nerve conduction function. Glucose absorption
in the rat intestinal segments exposed to 5 μg/mL of BDE-85 and BDE-209 was significantly reduced for both
the compounds tested. Lastly, mice when exposed to 0.25 mg/kg body weight for four days showed a disruption
in oxidant and antioxidant equilibrium. The tissues namely liver and brain have shown increase in the levels of
lipid hydroperoxides indicating oxidative stress. Moreover, all the protective enzymes namely superoxide dismutase
(SOD), glutathione peroxidase (GPx), catalase, and glutathione S transferase (GST) have shown tissue
specific alterations indicating the induction of damaging oxidative stress and setting in of lipid peroxidation in
exposed animals. The results indicate monitoring of PBDEs in the environment is essential because levels as
low as 5 μg/mL and 0.25 mg/kg body weight were able to cause damage to the functions of rodents.
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