Hexabromocyclododecane and tetrabromobisphenol-A in indoor dust from France, Kazakhstan and Nigeria: Implications for human exposure

Concentrations of hexabromocyclododecane isomers (α-, β- and γ-HBCDs) and tetrabromobisphenol-A (TBBP-A) were measured – for the first time – in indoor dust from homes, offices and cars from France, Kazakhstan and Nigeria. ΣHBCDs in French and Kazakhstani house dust (median = 1351 and 280 ng g⁻¹, respectively) were consistent with previous reports from the UK and Romania, respectively. Concentrations of ΣHBCDs in Nigerian domestic dust (median = 394 ng g⁻¹) were substantially higher than those reported from Egyptian homes. In general, concentrations of ΣHBCDs in the studied microenvironments were higher than those of TBBP-A, which may be attributed to the major application of TBBP-A as a reactive flame retardant; rendering its release to dust more difficult. Statistical analysis revealed significantly lower ΣHBCDs in French houses than those found in both offices and cars, while ΣHBCDs in cars from Kazakhstan were higher (P < 0.05) than those in homes and offices. Moreover, TBBP-A concentrations in car dust from Nigeria were lower than those found in homes and offices. Exposure estimates revealed higher intake of HBCDs and TBBP-A by toddlers via indoor dust ingestion compared to adults. Combined with their low body weight, this can raise concerns over the potential adverse health effects of such high exposure in toddlers.