Occurrence and exposure risk assessment of organic micropollutants in indoor dust from Malaysia

Indoor dust is an important source of human exposure to hazardous organic micropollutants (OMPs) because humans spend about 90 % of their time in the indoor environments. This study initially analyzed the concen-trations and compositions of OMPs in the dust of different indoor environments from Kuala Lumpur, Malaysia. A total of 57 OMPs were detected and assigned to 7 chemical classes in this study. The total concentration of OMPs ranged from 5980 to 183,000 ng/g, with the median concentration of 46,400 ng/g. Personal care products, organophosphate esters, and pesticides were the dominant groups, with their median concentrations at 12,000, 10,000, and 5940 ng/g, respectively. The concentrations and compositions of influential OMPs varied in different microenvironments, suggesting different sources and usage patterns in the house. Then, the noncarcinogenic and carcinogenic risks of exposure to these substances for diverse age groups were assessed based on the median concentration. Cumulative noncarcinogenic risks of these OMPs via ingestion pathway were estimated to be negligible (1.41 x 10(-4) -1.87 x 10(-3)). The carcinogenic risks of these OMPs were higher than 10-6 (1.63 x 10(-6) - 6.17 x 10(-6)) and should be noted. Theobromine accounted for more than 89 % of the cumulative cancer risk, implying that the carcinogenic risk of theobromine needs further monitoring in the future. Toddler was the most affected group for cancer risk among all the age groups, regardless of the microenvironments. These findings from this study may provide a benchmark for future efforts to ensure the safety of indoor dust for the local residents.

Automated summary

This study analyzed the concentrations and compositions of hazardous organic micropollutants (OMPs) in indoor dust from different indoor environments in Kuala Lumpur, Malaysia. The study detected 57 OMPs classified into 7 chemical classes, with personal care products, organophosphate esters, and pesticides as dominant groups. Noncarcinogenic risks were found to be negligible, while carcinogenic risks were higher and especially highlighted for theobromine. Toddler age group showed the highest cancer risk among all age groups across different microenvironments, suggesting the need for further monitoring and safety measures.