Fluoranthene Is one of the polynuclear aromatic hydrocarbons with four benzene rings. Because of Its toxicity, mutagenlclty, and carclnogenlclty, fluoranthene Is on the black lists of 129 and 68 priority pollutants established by US Environmental Protection Agency and the People's Republic of China, respectively. In recent years, the amount of fluoranthene In the aquatic environment has been Increasing with Increases In anthropogenlc discharge. Based on the biological investigation of tidal water In the Futlan mangrove, Cycioteila ~aspla was selected as the dominant algal species to determine the toxicity of fluoranthene towards C. caspla alga and to Investigate the blodegradatlon of fluoranthene by C. caspla under pure culture. The toxicity experiment showed that the 96-h EC50 value for fluoranthene was 0.2 mg/mL. Four parameters, namely C. caspla algal growth rate, chlorophyll (Chl) a content, cell morphology, and superoxlde dlsmutase (SOD) activity, were chosen as Indices of toxicity and were measured at 6 d (144 h). The results showed that: (Ⅰ) the toxicity of fluoranthene towards C. caspla alga was obvious; (Ⅱ) C. caspla algal growth rate and Chl a content decreased with Increasing concentrations of fluoranthene; and (Ⅲ) the rate of cell deformation and SOD activity Increased with Increasing concentrations of fluoranthene. The blodegradatlon experiment showed that: (Ⅰ) the rate of physical degradation of fluoranthene was only 5.86%; (Ⅱ) the rate of blodegradatlon of fluoranthene on the 1st and 6th days (l.e. at 24 and 144 h) was approximately 35% and 85%, respectively; and (Ⅲ) the blodegradatlon capability of C. caspla alga towards fluoranthene was high. It is suggested that further Investigations on the toxicity of fluoranthene towards algae, as well as on algal blodegradatlon mechanisms, are of great Importance to use C. caspla as a biological treatment species In an organic wastewater treatment system.
Spatial and temporal distribution of octylphenol (OP) and nonylphenol (NP) in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from 11 sites during the period of September- December 2004. Concentrations of OP and NP ranged from 11.3 to 348 ng/L and from 29 to 2591 ng/L, respectively. The high levels of NP and OP were found in November and December than in September and October. The levels of OP and NP have no significant spatial differences except September. Total organic matter in the sediments appeared to be an important factor in controlling the fate of these compounds in the aquatic environment.
LI Xiang-liLUAN Tian-gangLIANG YanWONG Ming-hungLAN Chong-yu