Distributions of phthalic esters carried by total suspended particulates in Nanjing, China.

Atmospheric trace phthalic esters (PAEs) carried by total suspended particulates were systematically investigated. A total of 450 air samples were collected at six typical locations and three specific micro-environmental sites (a stadium with a new plastic track, new cars, and a farming greenhouse with plastic film) in Nanjing metropolitan area of China from April 2009 to January 2010. The samples were analyzed by high-performance liquid chromatography and ultraviolet detection. The results are summarized as follows: (1) The dominant PAEs are dimethyl phthalate (DMP), dibutyl phthalate (DBP), and diethylhexyl phthalate (DEHP), which were found in the atmosphere of Nanjing. The average concentrations of DMP, DBP, and DEHP were 10.5 ± 1.2, 62.3 ± 4.5, and 33.3 ± 2.5 ng m(-3), respectively, constituting 9.9%, 58.7%, and 31.4% of total PAEs (106 ± 8.2 ng m(-3)). (2) The dynamic variations of atmospheric PAEs in the three specific micro-environmental sites showed that the PAE concentrations in the stadium with a new plastic track reduced to normal after 1 month remediation, while new cars need 6 months to remove their effect. The levels of PAEs in a farming greenhouse with plastic film were relatively high, but little PAEs accumulated in vegetables. (3) The vertical profiles from 1.5 to 40 m above ground display some fluctuations in PAE concentration, but no significant height dependence. This information will make a valuable contribution to the examination of the influence of atmospheric PAEs on the environment and human health.