Environmental characterization of 4,4′-dichlorobenzophenone in surface waters from Macao and Hong Kong coastal areas (Pearl River Delta) and its toxicity on two biological models: Artemia salina and Daphnia magna

• Published in: Ecotoxicology and environmental safety 2019-04, Vol.171, p.1-11
• Main Authors: Ivorra, Lucia, Cardoso, Patricia G., Chan, Shek Kiu, Tagulao, Karen, Cruzeiro, Catarina
• Format: Article
• Language: English
• Subjects: DDT; Dicofol; EC50; LC50; Metabolite; Organochlorine pesticides
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2018.12.054

The Pearl River Delta (PRD) is one of the areas with higher environmental concentration of organochlorine pesticides (OCPs), being DDT one of the most abundant. In this work, 4,4′-dichlorobenzophenone (4,4′-DCBP), a common metabolite of dicofol (DDT related) and DDT, was quantified in surface waters of Hong Kong and Macao, together with the analysis of physicochemical and nutrients parameters. Hong Kong presented higher 4,4′-DCBP mean levels (12.50 ng/L) than Macao (4.05 ng/L), which may be due to the use of dicofol as a pesticide and DDT as antifouling-paint for ships. The region presented a possible eutrophication state due to the high nutrients’ concentration. For the first time, toxicity evaluation of this metabolite in Artemia salina and Daphnia magna was done, in order to compute valid EC50s and theoretically evaluate the risk in the PRD. The toxicity results (EC50 = 0.27 mg/L for A. salina; and EC50 = 0.17 mg/L and LC50 = 0.26 mg/L for D. magna), together with the 4,4′-DCBP levels quantified, indicated a low environmental risk. [Display omitted] •Average 4,4′-DCBP concentrations (ng/L) detected in Hong Kong were 3-folds higher than in Macao.•Hong Kong and Macao areas presented possible eutrophication state due to high nutrients concentration.•Risk assessment results showed a low environmental risk (RQ