Occurrence, sources, and risk assessment of OCPs in surface sediments from urban, rural, and reclamation-affected rivers of the Pearl River Delta, China.
Sediments were collected to a depth of 20 cm from urban, rural, and reclamation-affected rivers in the Pearl River Delta of China. In total, 16 organochlorine pesticides (OCPs) were analyzed in all sediment samples, and the occurrence, possible sources, toxicity, and health risks of OCPs were evaluated to compare the contamination characteristics of OCPs in sediments among the three types of rivers. The results showed that concentrations of Σ16OCPs in sediments from the three rivers followed the order urban river > reclamation-affected river > rural river, with a mean value of 247.21, 232.91, and 114.92 μg/kg, respectively, and the predominant OCPs were hexachlorobenzene (HCB), dieldrin, aldrin, endrin, and hexachlorocyclohexanes (HCHs). Source diagnostics illustrated that there might be recent input of HCHs, dichlorodiphenyltrichloroethanes (DDTs), and endosulfan in some sampling sites. Based on the soil quality thresholds of China, both HCHs and DDTs fell within the range of class II criteria except for some sediment samples in urban rivers with lower levels (below class I criteria). According to sediment quality guidelines, 92.86 % of samples were predicted to be toxic. The health risk assessment showed that OCPs would not pose a threat to people via dermal contact, ingestion, and inhalation, and the followed order of incremental lifetime cancer risks for OCPs in sediment samples was reclamation-affected river > urban river > rural river.
State Key laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, People's Republic of China.
Wei
W
Wang
State Key laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, People's Republic of China. junhongbai@163.com.
Junhong
J
Bai
College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, People's Republic of China.
Min
M
Xi
State Key laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, People's Republic of China.
Qingqing
Q
Zhao
State Key laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, People's Republic of China.
Guangliang
G
Zhang
State Key laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, People's Republic of China.
Xiaojun
X
Wen
School of Nature Conservation, Beijing Forestry University, Beijing, 100083, People's Republic of China.
Rong
R
Xiao
D002681:China; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments; D001556:Hexachlorocyclohexane / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis; D010575:Pesticides / Q000032:analysis*; D018570:Risk Assessment; D045483:Rivers; D012987:Soil; D014874:Water Pollutants, Chemical / Q000032:analysis*
D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D012987:Soil; D014874:Water Pollutants, Chemical; D001556:Hexachlorocyclohexane
Distribution; Incremental lifetime cancer risk; Organochlorine pesticides; Potential sources; River sediment; Toxicity