[Primarily study of alkylphenols in sediment core from Nam Van artificial lake of Macao]

Alkylphenols, nonylphenols (NPs), octylphenol (OP), are known to have estrogenic effects. In a sediment core from Nam Van artificial lake of Macao, the concentrations of NPs ranged from 2.17 to 5.91 microg/g, with mean value of 3.66 microg/g during the estuarine sedimentary environment from 1970s-1980s and from 0.69 to 3.04 microg/g, with mean value of 2.08 microg/g during lagoon sedimentary environment in 1990s. The concentrations of OP during the initial stages of lagoon environment in the early 1990s were similar to that in the estuarine environment, and ranged from 14.33 to 39.11 ng/g. Subsequently, the concentration of OP was rapidly decreasing from 6.52 to 2.58 ng/g. Sources of APs in the estuarine condition included the urban runoffs from the upstream waters of Pearl River Delta and Macao city, but just from Macao in the lagoon condition. Consequently, concentration of APs in estuary condition was higher than that in lagoon condition. The vertical profile of concentration of APs in the sediment core, to some degree, was correlated with the development degree of regional economy and the proceeding of wastewater treatment. The results also showed that the alkylphenols in overlapping silty layer preferred to transfer downward to filling sandy layer.