Cross-regional scale studies of organochlorine pesticides in air in China: Pollution characteristic, seasonal variation, and gas/particle partitioning

Liang Wang; Gang Cao; Li-Yan Liu; Zi-Feng Zhang; Shi-Ming Jia; Meng-Qi Fu; Wan-Li Ma

doi:10.1016/j.scitotenv.2023.166709

Cross-regional scale studies of organochlorine pesticides in air in China: Pollution characteristic, seasonal variation, and gas/particle partitioning

Sci Total Environ. 2023 Dec 15:904:166709. doi: 10.1016/j.scitotenv.2023.166709. Epub 2023 Sep 1.

Authors

Liang Wang¹, Gang Cao², Li-Yan Liu¹, Zi-Feng Zhang¹, Shi-Ming Jia¹, Meng-Qi Fu³, Wan-Li Ma⁴

Affiliations

¹ International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem (HPKL-PEE), Harbin Institute of Technology, Harbin 150090, China.
² Shenzhen Key Laboratory of Organic Pollution Prevention and Control, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China.
³ International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
⁴ International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem (HPKL-PEE), Harbin Institute of Technology, Harbin 150090, China. Electronic address: mawanli002@163.com.

PMID: 37659555
DOI: 10.1016/j.scitotenv.2023.166709

Abstract

Few simultaneous studies of organochlorine pesticides (OCPs) in the atmosphere have been conducted across Southeast and Northeast China, and no data on the gas/particle (G/P) partitioning behaviors of several current-use OCPs are available. In this study, a one-year synchronous monitoring program was conducted for OCPs in Chinese atmosphere spanning 30° latitude and 60 °C temperature. A total of 111 pairs of gas and particle samples were collected from Mohe and Harbin in Northeast China and from Shenzhen in Southeast China. The detection frequency for 66.7 % of the OCPs exceeded 80 %, indicating their prevalence in the atmosphere. The concentrations of individual OCPs spanned six orders of magnitude, indicating different pollution levels. Highest levels of hexachlorobenzene were observed at all sites. Banned OCPs were found predominantly in secondary distribution patterns, whereas current-use OCPs were dominated by primary distribution patterns. In Harbin and Mohe, the concentrations of OCPs were highest in summer, followed by autumn and winter. No obvious seasonal variation was observed in Shenzhen associated with different cultivation types. At all three sites, OCPs were predominantly found in the gas phase, and higher percentages of particle-phase OCPs were observed in Harbin and Mohe than in Shenzhen. In this study, G/P partitioning models were used to study the G/P partitioning mechanism of OCPs. The Li-Ma-Yang model provided the most accurate prediction of the G/P partitioning behavior of OCPs with high molecular weights and low vapor pressures, particularly at low temperatures. However, OCPs with lower molecular weights and higher vapor pressures were predominantly in the equilibrium state, for which the Junge-Pankow model was suitable. This systematic cross-scale study provides new insights into pollution, G/P partitioning, and the environmental behavior of OCPs in the atmosphere.

Keywords: Atmosphere; Gas/particle partitioning; Organochlorine pesticides; Pollution characteristic; Seasonal pattern.