The problem with implementing fish farms in agricultural regions: A trial in a pampean pond highlights potential risks to both human and fish health

The safety of creating fish farms in agricultural settings was evaluated by growing Piaractus mesopotamicus in a pond, while crops where cultivated in a nearby field under a pesticide application regime typical of the Pampa region. Atrazine, glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), were detected in the water of the pond at concentrations ranging between 92 and 118 mu g/L for atrazine, 12 and 221 mu g/L for glyphosate and 21 and 117 mu g/L for AMPA. Atrazine and malathion were detected in fish muscles at concentrations ranging between 70 and 105 mu g/kg for atrazine and 8.6 and 23.7 mu g/kg for malathion. Compared to fish raised in a pisciculture, fish from the agricultural pond presented reduced values of pack cell volume, hemoglobin, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration, together with significantly greater cholinesterase activity in both plasma and liver and reduced glutathione-S-transferase activity in the liver. A comet assay also demonstrated that P. mesopotamicus from the agricultural pond presented a significantly greater level of DNA damage in both erythrocytes and gill cells. Overall, the present study demonstrates that pisciculture ponds established in an agricultural setting may receive pesticides applied to nearby cultures and that these pesticides may be taken up by the fish and affect their physiology and health. The accumulation of pesticides residues in fish flesh may also present a risk to human consumers and should be closely controlled. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The study evaluated the safety of fish farms in agricultural settings by growing Piaractus mesopotamicus in a pond, revealing the presence of pesticide residues in fish bodies which affected their physiology and health. Fish from the agricultural pond showed significantly higher DNA damage levels, as well as decreased levels of hemoglobin and other physiological indicators.