Toxicity of several important agricultural antibiotics to Artemia

The possible effects of antibiotic drug contamination in marine and brackish systems were evaluated using a new methodological approach. Five drugs, namely aminosidine (A), bacitracin (B), erythromycin (E), flumequine (F) and lincomycin (L), were subjected to toxicity tests using nauplii and cysts of Artemia as a model of drug contamination from intensive farming. Tests on nauplii were performed by the ArToxKit-M test (Persoone and Van Haecke, 1981), test on cysts by our experimental protocol (Migliore et al., 1993a, b). The lethal effect on nauplii were evaluated between 24 and 120 h: the sequence of decreasing toxicity was B> F> L> A> E. A high toxicity of B was recorded. In addition, B and F were tested on cysts. B significantly lowered hatching; this depended on the interference of B with normal development. F did not depress hatching, but it deeply altered nauplii pigmentation. The interest in assessing the possible environmental risks due to drugs used in intensive farming and the need for suitable standards to improve sea-water quality is discussed.