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Organochlorine pesticides (OCPs) are a typical group of persistent organic pollutants and were widely distributed in soils, atmosphere, and water. They can be enriched in animals and crops including vegetables, and then endanger human body’s health. Greenhouse was widely used to cultivating vegetables in China, therefore, it is necessary to study of the distribution and accumulation of OCPs in vegetables and environmental behavior of OCPs in greenhouse. The information can provide valuable suggestion for crops security and human health.In this study, we analysed the distribution and accumulations of OCPs in tomatoes, eggplants, cucumbers, pumpkins and peppers in greenhouse, and soils, atmosphere. Based on enantiomeric fraction (EF) of chiral OCPs, the degradation, distribution and migration of OCPs in soil-vegetable-air were also analysed.The concentration of the OCPs in vegetable tissues ranged from 2.12~68.73 ng/g,with mean of 12.25 ng/g, OCPs concentration in soils ranged from 23.78~38.74 ng/g, with mean of 31.66 ng/g, OCPs concentration in air ranged from 54.79~185.87 pg/m3 , with mean of 119.16 pg/m3, OCPs concentration in plastic films ranged from 35.46~77.61 ng/g, with mean of 55.54 ng/g. According to bioaccumulation factors (BCFs),β-HCH was more accumulated than other isomers in roots of vegetables except eggplant. o,p’-DDT was more accumulated than other isomers and degradation products of DDT in roots of vegetables except cucumber. Although BCFs of p,p’-DDD were nearly zero in all vegetables roots, p,p’-DDD was one of the main of DDTs in soils. Based on BCFs, OCPs in roots were mainly from soil, and atmospheric deposition was a main source of -HCH on leaves of cucumber.The concentration of HCHs of atmosphere in peppers greenhouses was lower than those in greenhouses of cucumbers and tomatoes, but higher than those of outside. Accumulations of DDTs in atmosphere of cucumbers and tomatoes greenhouses and outside were all higher than those in peppers greenhouses. The tendencies of soil-to-air emission can be described by calculating the fugacities of the chemicals in both soil and atmosphere. Fugacities of -HCH, p,p’-DDE and CC (cis-chlordane) were approximately equal to 0.5 in greenhouse which were used to cultivated eggplants and tomatos. It indicated that OCPs were in balance between soil and atmosphere. The fugacities of p,p’-DDD were lower than 0.15 and indicated that precitiation of p,p’-DDD from air to soil occur at the greenhouse of eggplants and tomatos. The fugacities ofγ-HCH、TC (trans-chlordane) were high than 0.85 and indicated that evaporation ofγ-HCH、TC from soil to air occurred at the greenhouse of eggplants and tomatos. The 0.5 of fugacities ofβ-HCH, -HCH, p,p’-DDT, p,p’-DDD and CC implied OCPs balance between soil and air in greenhouse of pepper, while the 0.85 of fugacities ofγ-HCH, p,p’-DDE and TC showed evaporation from soils to air.Combining the molecular mark tracer method and EFs of chiral OCPs in soils in the value of sources of OCPs analysis, it could be resolved that HCHs and DDTs in greenhouse were from historical application. Enantiomers of five chiral OCPs were selectively enrichment in the greenhouse soils, atmosphere and vegetable tissues samples.
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