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Pesticides represent one of the largest intentional inputs of potentially hazardous compounds into agricultural soils. However, as an important vegetable producing country, surveys on pesticide residues in soils of vegetable production areas are scarce in China. This study presented the occurrence, spatial distribution, correlation between vegetable types and pesticides, and ecological risk evaluation of 94 current-use pesticides in 184 soil samples from vegetable production areas of Zhejiang province (China). The ecological risks of pesticides to soil biota were evaluated with toxicity exposure ratios (TERs) and risk quotient (RQ). The pesticide concentrations varied largely from below the limit of quantification to 20703.06 μg/kg (chlorpyrifos). The situation of pesticide residues in Jiaxing is more serious than in other cities. Soils in the vegetable areas are highly diverse in pesticide combinations. Eisenia fetida suffered exposure risk from multiple pesticides. The risk posed by chlorpyrifos, which exhibited the highest RQs at all scenarios, was worrisome. Only a few pesticides accounted for the overall risk of a city, while the other pesticides make little or zero contribution. This work will guide the appropriate use of pesticides and manage soil ecological risks, achieving green agricultural production. [Display omitted] • 184 soil samples in 6 cities were collected to identify 94 current-use pesticides. • 79% of the tested pesticides were detected over limit of quantitation. • The situation of pesticide residues in Jiaxing is more serious than in other cities. • Soils in the vegetable areas are highly diverse in pesticide combinations. • Eisenia fetida suffered exposure risk from multiple pesticides. [ABSTRACT FROM AUTHOR]

• 19% leafy vegetable samples contained synthetic pyrethroids. • 81 samples were detected with more than 2 SPs. • The detection rate of the individual SP tended to show a downward trend. • Dietary exposures of synthetic pyrethroids in leafy vegetables were acceptable. Leafy vegetables have high nutritional value and are very popular in China. However, the long-term variation in residues and integrated risks of synthetic pyrethroids (SPs) in these vegetables have not been well examined. In this study, a total of 1005 samples were collected from 55 markets during 2017–2019. The cumulative exposure to nine kinds of SPs in Zhejiang, China, through the consumption of nine leafy vegetables was analyzed, and the potential integrated risk was assessed by the relative potency factor. A total of 191 samples were detected with SPs residues. The most frequently detected SPs were λ-cyhalothrin and cypermethrin. The integrated risk assessment results revealed that the dietary risk for these SPs via leafy vegetable exposure is acceptable for children, adults and elderly individuals. The data provided here will be helpful for the government to formulate food policies in China. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides (OCPs) are organic pollutants that are persistent and undegradable in the environment. To investigate their residual concentrations, spatial and temporal distributions, and the relationship with the crops planted, 12 individual OCPs in 687 soil samples from Jiangsu, Zhejiang and Jiangxi provinces of southeast China were examined. The detection frequencies of OCPs in the studied areas were 1.89%–64.9%. The concentrations of dichloro-diphenyl-trichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), and endosulfans ranged from 0.01 to 5659 μg/kg, 0.03–3.58 μg/kg, and 0.05–3235 μg/kg, respectively. Jiangsu was mainly contaminated by p,p'-DDT, p,p'-DDD and endosulfan sulfate, Zhejiang was more polluted by OCPs except δ-HCH, and Jiangxi was more vulnerable to the contamination of OCPs except o,p'-DDE. The partial least-squares discrimination analysis (PLS-DA) model with RX2 36.3–36.8% revealed that compounds with similar chemical properties tended to appear in the same year and month. All crop lands were polluted by DDTs and Endosulfans. The highest concentrations of DDTs and Endosulfans were found in citrus and vegetable fields, respectively. This study offers new insight into the layout and partitioning of OCPs in agricultural land and into insecticide management on public health and ecological safety. [Display omitted] • 687 soil samples in 6 consecutive years were collected to identify OCPs. • p,p'-DDE, p,p'-DDT and p,p'-DDD were the most frequently detected. • Coastal area and lake district were more concentrated of OCPs. • Chemical properties might influence the temporal distribution of OCPs. • DDTs and Endosulfans were the primary pollutants in agricultural soil. [ABSTRACT FROM AUTHOR]