Low malathion concentrations influence metabolism in Chironomus sancticaroli (Diptera, Chironomidae) in acute and chronic toxicity tests. Organophosphate compounds are used in agro-systems, and in programs to control pathogen vectors. Because they are continuously applied, organophosphates often reach water sources and may have an impact on aquatic life. The effects of acute and chronic exposure to the organophosphate insecticide malathion on the midge Chironomus sancticaroli are evaluated. To that end, three biochemical biomarkers, acetylcholinesterase (AChE), alpha (EST-α) and beta (EST-β) esterase were used. Acute bioassays with five concentrations of malathion, and chronic bioassays with two concentrations of malathion were carried out. In the acute exposure test, AChE, EST-α and EST-β activities declined by 66, 40 and 37%, respectively, at 0.251 µg L-1 and more than 80% at 1.37, 1.96 and 2.51 µg L-1. In chronic exposure tests, AChE and EST-α activities declined by 28 and 15% at 0.251 µg L-1. Results of the present study show that low concentrations of malathion can influence larval metabolism, indicating high toxicity for Chironomus sancticaroli and environmental risk associated with the use of organophosphates

Paracetamol (PCM), or acetaminophen, is one of the most used drugs for human treatment of pain and fever. Since it has often been found in the aquatic environment, the aim of this study was to investigate the effects of PCM on the reproductive axis of male Rhamdia quelen catfish.

Pesticide contamination of food and environmental matrices represents a potential risk to human health. This study investigated the toxicological effects of commercial glyphosate and dicamba-based herbicide formulations, individually and in combination, on human intestinal epithelial Caco-2 cells. Cells were exposed to a concentration range of 0.1–10,000 mg/L for 24, 48, and 72 h to determine IC₅₀ values. Subsequent assays were conducted using concentrations based on the lowest IC₅₀ obtained and in the limits established by the Environmental Protection Agency for drinking water. After 48 h of exposure, glyphosate at the highest tested concentration, as well as co-exposure to glyphosate and dicamba, induced significant cytotoxicity, modulation of oxidative stress parameters, and alterations in antioxidant defenses, accompanied by increased rates of apoptosis and necrosis. Dicamba exposure alone also resulted in elevated apoptotic and necrotic cell populations. A reduction in N-acetyl-β-D-glucosaminidase activity was observed across most tested concentrations, suggesting impaired inflammatory response capacity. This work identified alterations in Caco-2 that impair cellular homeostasis by cytotoxicity, alterations in oxidative stress, antioxidant response, inflammation, apoptosis and necrosis. Future studies investigating inflammatory pathways, genetic damage, and assays with in vivo and in silico models are important to elucidate the mechanism of the cellular damage caused by exposure to these herbicides.