Individual and Joint Toxicity of Three Chloroacetanilide Herbicides to Freshwater Cladoceran Daphnia carinata.

Key Laboratory of Agro-Environment in the Tropics, Ministry of Agriculture, Key Laboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institution, South China Agricultural University, Guangzhou, 510642, China, .
Bulletin of Environmental Contamination and Toxicology (Impact Factor: 1.11). 12/2012; 90(3). DOI: 10.1007/s00128-012-0898-y
Source: PubMed

ABSTRACT Individual and joint toxicity of three chloroacetanilide herbicides to a freshwater cladoceran were studied. The 48 h-LC(50) values of alachlor, acetochlor and butachlor to Daphnia carinata Dc42 were 11.1, 11.8 and 3.45 mg L(-1), respectively. The toxicity was significantly (p < 0.05) related to hydrophobicity. The additive indexes of binary mixtures of three herbicides were less than zero and it showed antagonism. The body length of D. carinata treated with high concentration of herbicides was shorter than that of control group significantly (p < 0.05). It suggests that joint actions must be considered when assessing the acute toxicity of chloroacetanilide herbicides to D. carinata.

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