Hexabromocyclododecanes and Tetrabromobisphenol-A in Indoor Air and Dust in Birmingham, UK: Implications for Human Exposure

Abstract

Hexabromocyclododecanes (α-, β-, and γ-HBCDs) and tetrabromobisphenol-A (TBBP-A) were determined in indoor air from homes (n = 33; median concentrations ΣHBCDs = 180 pg m⁻³; TBBP-A = 15 pg m⁻³), offices (n = 25; 170; 11), public microenvironments (n = 4; 900; 27) and outdoor air (n = 5; 37; 1). HBCDs and TBBP-A were also determined in dust from homes (n = 45; median concentrations ΣHBCDs = 1300 ng g⁻¹; TBBP-A = 62 ng g⁻¹), offices (n = 28; 760; 36), cars (n = 20; 13,000; 2), and public microenvironments (n = 4; 2700; 230). While ΣHBCDs in car dust significantly exceeded (p < 0.05) those in homes and offices, TBBP-A in car dust was significantly lower (p < 0.05) than that in homes and offices. No significant differences were observed between ΣHBCDs and TBBP-A in air or dust from homes and offices. Compared to dietary and inhalation exposures, dust ingestion constitutes an important pathway of exposure to HBCDs and TBBP-A for the UK population. Specifically, using average dust ingestion rates and concentrations in dust, dust ingestion constitutes for adults 34% (TBBP-A) and 24% (HBCDs) of overall exposure, and for toddlers 90% (TBBP-A) and 63% (HBCDs). Inhalation appears a minor exposure pathway to both HBCDs and TBBP-A. On average, dust is 33% α-, 11% β-, and 56% γ-HBCD, while air is 22% α-, 11% β-, and 65% γ-HBCD.