Distribution characteristics of nonylphenol in Jiaozhou Bay of Qingdao and its adjacent rivers

Nonylphenol (NP) is an endocrine disruptor and causes harmful effects including feminization and carcinogenesis to various organisms. Consequently, its contamination in natural waters has received wide concerns. This study aims to investigate the seasonal variation and contamination level of nonylphenol in Jiaozhou Bay of Qingdao and its adjacent rivers. A total of 10 phenolic compounds including alkylphenol, chlorophenol and bisphenol A were measured in water, suspended solids and sediments in winter (January), spring (April) and summer (July) of 2005. The results showed that nonylphenol accounted for the majority of phenolic compounds and that its concentrations in Jiaozhou Bay ranged between 20.2-269 ng l(-1), 17.1-77.5 ng l(-1) and 3.6-299 ng g(-1)dw in surface water, suspended solids and surface sediment, respectively. There existed a significant correlation between nonylphenol in water and in suspended solids. The concentration of nonylphenol in water varied with seasons and generally showed a decreasing order of July>April>January. The concentrations of nonylphenol in the adjacent rivers were much higher with the maximum of 28600 ng l(-1) in surface water. The spatial distribution of nonylphenol in Jiaozhou Bay was influenced by freshwater discharge from the adjacent rivers as well as current circulation system within the bay. The pollution level of nonylphenol in Jiaozhou Bay was comparable to other highly polluted areas of the world and its possible effects on local organisms were discussed.