Occurrence, distribution, and risk assessment of pesticides in surface water and sediment in Jiangsu Province, China.

The occurrence and distribution of 157 pesticides were investigated in surface water and sediment in Jiangsu Province, China. Gas chromatography-mass spectrometry was used to analyze and quantify these pesticides, and the risk quotient method was used to evaluate their respective environmental risk. The results showed that 91 pesticides were detected in surface water. The organophosphates (OPPs), fungicides, and amide herbicides were predominant. The total concentration in surface water ranged from 63.7 to 22,463 ng/L, 3.90 to 7262 ng/L, and ND to 34,120 ng/L, respectively. The mean concentration was 3479 ng/L, 1644 ng/L, and 1878 ng/L, respectively. The concentration range of detected pesticides in the Yangtze River Basin was generally lower than that in the Huai River Basin. In sediment samples, a total of 63 pesticides were detected. OPPs and amide herbicides were also ranked highest; the total concentration in sediment samples ranged from 2951 to 47,739 ng/g and 106 to 12,996 ng/g, respectively. And the mean concentrations was 6971 ng/g and 5130 ng/g, respectively. Suqian City had the highest concentration for OPPs and amide herbicides in the Huai River Basin, followed by Huai'an City, while Nanjing City and Yangzhou City ranked highest in the Yangtze River Basin. The spatial distribution of pesticides in Jiangsu Province indicated a concentration significantly higher in the western and northern regions than in the eastern and southern regions, and a concentration generally higher in lakes than in rivers. The risk assessment results showed that OPPs, fungicides, amide herbicides, organochlorines, and triazine herbicides in most surface water samples posed a high risk and had regional pollution characteristics. In sediment samples, organochlorines, carbamates, other herbicides, and other insecticides posed a high risk in northern Jiangsu Province, whereas OPPs, amide herbicides, and triazine herbicides posed high risks everywhere in Jiangsu Province.

[Pollution Level, Distribution Characteristic, and Ecological Risk Assessment of Environmentally Persistent Pharmaceutical Pollutants in Surface Water of Jiangsu Province].

Because Jiangsu is an important economic province of China, it is necessary to examine the pollution characteristics and assess the ecological risk of environmentally persistent pharmaceutical pollutants (EPPPs) in this region. In this study, surface water samples were obtained from grade 1-4 rivers and lakes (with an area of 50 km2 or more) in Jiangsu Province, and then analyzed to determine the pollution level of EPPPs. In total, 35 EPPPs were detected in the surface water of Jiangsu Province, with total concentrations in the samples ranging from 66.74 to 2189.83 ng·L-1. The 17 EPPPs with a detection rate of more than 25% are discussed in this study. The total concentrations of 35 EPPPs were 72.48-1142.79 ng·L-1, and the mean concentration was 345.20 ng·L-1. The total concentration of EPPPs was higher in the north and south than in the central part of Jiangsu. Yangzhou city had the highest concentration of EPPPs in the whole province, and the main sources of this pollution were domestic sewage, shipping sewage discharge, and drug use in fishery breeding. The total concentration of EPPPs decreased on both sides of the region, with the Beijing-Hangzhou Canal and waste from the Yellow River forming the middle line. An ecological risk assessment of 17 EPPPs showed that single target drugs posed a low risk to water ecology in Jiangsu Province. The combined risk quotient of 17 EPPPs in water of Jiangsu Province was 0.03-0.52, indicating that EPPPs posed a low to moderate risk.