Indoor phthalates from household dust in Qatar: implications for non-dietary human exposure

Phthalates are ubiquitous semi-volatile organic compounds in the indoor environment present in various consumer products such as cosmetics, polyvinylchloride (PVC) flooring, food packing, and many others. Indoor phthalate concentrations were investigated in 15 buildings including 11 homes, 3 laboratories, and 1 from a hospital in Qatar. Dust samples were collected from vacuum cleaning bags usually used for cleaning homes, labs, and hospitals. The main objectives of this study was to determine the occurrence and concentration of phthalates in dust in Qatar and consequently to estimate the non-dietary human exposure. Eleven phthalates was analyzed. The major identified phthalate compounds at homes in Qatar were bis(2-ethylhexyl) phthalate unlabeled (DEHP) and diisononyl phthalate (DINP) at a geometric mean of 288 μg/g (median 395 μg/g) and 106 μg/g (median 101 μg/g) accounting for 57% and 23% of the total measured phthalates, respectively. The major phthalate compounds found in the first lab building were DEHP and DINP with a median of 4861 μg/g and 943 μg/g, respectively, accounting for 82% and 16% of the total phthalates. For the second lab building, the major phthalates were DEHP with a median of 466 μg/g, accounting for 20% of the total phthalates measured, and DINP median of 1725 μg/g, accounting for 71% of the total measured phthalates. The dust sample tested from hospital building had DEHP as the major phthalate compound with a median of 793 μg/g, accounting for 4.0% of the total measured phthalates, and DINP with a median of 19,626 μg/g, accounting for 94%. The estimated human non-dietary exposure for children, adults, and toddlers was based on phthalate concentrations (median) and found to be 225 ng/kg bw/day for children, 2328 ng/kg bw/day for adults, and 2099 ng/kg bw/day for toddlers.