Albendin_2021_Int.J.Environ.Res.Public.Health_18_

Pharmaceutical products, as well as insecticides and antimicrobials, have been extensively studied, but knowledge of their effects-especially those caused by their mixtures with microplastics-on aquatic organisms remains limited. However, it should be borne in mind that the state of knowledge on acute and chronic effects in aquatic organisms for pharmaceuticals and pesticides is not similar. In response, this investigation analyzed the presence of microplastics (polyvinyl chloride) and their impacts on the toxicity of chlorpyrifos (an insecticide) and triclosan (an antibacterial) when they coincide in the environment, alongside the two most consumed drugs of their type (hypolipemic and anticonvulsant, respectively), namely simvastatin and carbamazepine, in Artemia salina. LC(50) and cholinesterase enzyme activity were calculated to determine the possible neurotoxicity associated with emergent contaminants in the treatments. The LC(50) values obtained were 0.006 mg/dm(3) for chlorpyrifos, 0.012 mg/dm(3) for chlorpyrifos associated with microplastics, 4.979 mg/dm(3) for triclosan, 4.957 mg/dm(3) for triclosan associated with microplastics, 9.35 mg/dm(3) for simvastatin, 10.29 mg/dm(3) for simvastatin associated with microplastics, 43.25 mg/dm(3) for carbamazepine and 46.50 mg/dm(3) for carbamazepine associated with microplastics in acute exposure. These results indicate that the presence of microplastics in the medium reduces toxicity, considering the LC(50) values. However, exposure to chlorpyrifos and carbamazepine, both alone and associated with microplastics, showed a decline in cholinesterase activity, confirming their neurotoxic effect. Nevertheless, no significant differences were observed with the biomarker cholinesterase between the toxicant and the toxicant with microplastics.