LEACHING CHARACTERISTICS OF HEXABROMOCYCLODODECANES (HBCDs) FROM EXPANDED POLYSTYRENE BUOY IN WATER

Abstract

Hexabromocyclododecane (HBCD) is the second highest-volume BFR used after tetrabromobisphenol-A (TBBP-A) and before decabromodiphenylether. It is the principal flame retardant in polystyrene (PS) foams and is used as thermal insulation in the building industry.Technical HBCD is usually a mixture of the three diastereoisomers α, β and γHBCD. Normally, the γ isomer is the most abundant in commercial mixtures (75 -89%), followed by α and β isomer (10&#8211 13% and 1&#8211 12%, respectively).The different molecular properties (polarity, dipole moment and solubility in water) of α, β and γ isomers might lead to differences observed in their environmental behavior.The release of HBCD into the environment is considered as an issue of global concern. As additive BFR, HBCD is not covalently bonded to the material into which it is impregnated, leading to the risk of migration out of the product during production, use or disposal1. Some reports indicated that it is highly toxic to rats and induces cancer2,3. HBCD can also affect the normal uptake of neurotransmitters in rat brain4.Therefore, it is being considered under the framework of StockholmConvention on Persistence Organic Pollutants.HBCDhas attracted an increasing worldwide attention and therefore a vast literature is available on the detection of HBCD in the environmentcaused by the industrial or anthropogenic activity5-8. However, fascinating point is the he building industry.Technical HBCD is usually a mixture of the three diastereoisomers α, β and γHBCD. Normally, the γ isomer is the most abundant in commercial mixtures (75 -89%), followed by α and β isomer (10&#8211 13% and 1&#8211 12%, respectively).The different molecular properties (polarity, dipole moment and solubility in water) of α, β and γ isomers might lead to differences observed in their environmental behavior.The release of HBCD into the environment is considered as an issue of global concern. As additive BFR, HBCD is not covalently bonded to the material into which it is impregnated, leading to the risk of migration out of the product during production, use or disposal1. Some reports indicated that it is highly toxic to rats and induces cancer2,3. HBCD can also affect the normal uptake of neurotransmitters in rat brain4.Therefore, it is being considered under the framework of StockholmConvention on Persistence Organic Pollutants.HBCDhas attracted an increasing worldwide attention and therefore a vast literature is available on the detection of HBCD in the environmentcaused by the industrial or anthropogenic activity5-8. However, fascinating point is the