[Spatial and temporal distribution of organochlorine pesticides (OCPs) in surface water from the Pearl River Artery estuary].

Six water samples were collected, and twenty-one compounds of organochlorine pesticides (OCPs) in surface water from the Pearl River Artery estuary were analyzed quantitatively, based on USEPA 8000 series methods and under quality assurance and quality control (QA/QC). The total (particulate plus dissolved phase) concentration of OCPs in surface water from the Pearl River Artery estuary in both high flow season and low flow season were 9.7 ng/L-26.3 ng/L and 41.7 ng/L-122.5 ng/L respectively. The concentration of total HCHs and total other OCPs was much higher than that of DDTs. The seasonality of the concentration of OCPs was significantly, and the level of OCPs in low flow season was higher than that of OCPs in high flow season. The spatial and temporal distribution of OCPs suggested that there were significant differences of OCPs between the East River (Dongjiang) network and Guangzhou channel and the nonpoint-source pollution of OCPs was found in the Pearl River Artery estuary, particularly in high flow season.