Occurrence of phthalate diesters in indoor air from several Northern cities in Vietnam, and its implication for human exposure

Abstract

Phthalates are used as plasticizers to impart flexibility of plastics. Because of their toxicity, human exposure to phthalates is a concern. Little is known on the occurrence of and inhalation exposure to phthalates in indoor air. In this study, ten phthalates were measured in 97 indoor air samples collected from Northern Vietnam during September 2016 to January 2017. The mean concentrations of total phthalates (i.e., sum of ten phthalates) in particulate and gas phases ranged from 95.2 to 13,100μgg^-1 and from 57.0 to 14,900ngm^-3, respectively. In bulk indoor air samples (i.e., gas plus particulate phase), the mean concentration of total phthalates ranged from 106 to 16,000ngm^-3 (mean: 1040ngm^-3). Diethyl phthalate (DEP) was found at the highest concentration in indoor air at a concentration range of below the method quantitation limit (MQL) to 12,400ngm^-3 (mean: 376). Among various microenvironments, indoor air collected from hair salons contained the highest concentrations of phthalates (range: 596 to 16,000ngm^-3). Among the four northern Vietnamese cities studied, the highest concentrations of phthalates were found in indoor air samples from Hanoi. The calculated mean inhalation exposure doses to phthalates for infants, toddlers, children, teenagers, and adults were 780, 485, 416, 292, and 213ngkg-bw^-1d^-1, respectively.

Keywords: DEHP; DEP; Indoor air; Inhalation exposure; Phthalates.