Occurrence of and human exposure to organophosphate flame retardants/plasticizers in indoor air and dust from various microenvironments in the United States

The occurrence and profiles of 15 organophosphate flame retardants/plasticizers (OPFRs) (3 chlorinated [Cl-], 2 aryl-, 5 non-Cl alkyl-, and 5 other types of OPFRs) were investigated in indoor air and dust collected from various microenvironments, including homes in the Albany area of New York State, United States. Concurrent indoor air and dust were collected from floors and window sills at homes and fire stations to investigate the partitioning of OPFRs between the vapor and particulate phases of air and dust. The total concentrations of OPFRs in bulk air (vapor plus particulate phases) were found at several tens to hundreds of ng/m³, with mean concentrations that ranged from 0.12 ng/m³ for tripropyl phosphate (TPP) to 43.8 ng/m³ for tris(1-chloro-2-propyl)phosphate (TCIPP). TCIPP, triethyl phosphate (TEP) and tris(2-butoxyethyl)phosphate (TBOEP) were the predominant compounds found in bulk air, vapor phase, and dust. Among the ten types of microenvironments studied, indoor air samples collected from automobile parts shops contained the highest concentrations of OPFRs (mean: 258 ng/m³), followed by electronics shops, nail salons/shops that sell nail polish, and home construction/interior products shops. Estimated daily intakes of OPFRs via inhalation of air, dermal sorption, and ingestion of dust were 149, 279, and 390 ng/kg bw/day, respectively, which suggested that dust ingestion is an important source of human exposure to OPFRs among the indoor exposure pathways studied.