Comparative effect of technical and commercial formulations of methamidophos on sperm quality and DNA integrity in mice

Abstract

Methamidophos (MET), widely used in developing countries, is a highly neurotoxic organophosphate pesticide that has been associated with male reproductive alterations. Commercial formulations of pesticides used by agricultural workers and urban sprayers are responsible for thousands of intoxications in developing countries and may not have the same effects as active pure ingredients. Therefore, we compared effects of MET technical (METt) and commercial (METc) grades on sperm quality and DNA integrity. Male mice were injected (intraperitoneal, i.p.) with METt or METc (3.75, 5, and 7 mg/kg bw/day/4 days) and sacrificed 24 h post-treatment. Sperm cells collected from epididymis-vas deferens were evaluated for quality parameters, DNA damage by the comet assay, and lipoperoxidation by malondialdehyde (MDA) production. Erythrocyte acetylcholinesterase (AChE) activity was evaluated by acetylthiocholine inhibition as an index of overall toxicity. A dose-dependent AChE inhibition was observed with both formulations. Sperm quality was decreased after treatment with both MET compounds, but the commercial formulation showed stronger effects; a similar profile was observed with the DNA damage, being METc more genotoxic. None MET formulation increased MDA, suggesting no peroxidative damage involved. In summary, the commercial formulation of MET was more reprotoxic and genotoxic than the active pure ingredient, highlighting that commercial formulations must be considered for more appropriate risk assessment of pesticide exposures.

Toxic effects of methamidophos on paraoxonase 1 activity and on rat kidney and liver and ameliorating effects of alpha‐tocopherol

“…Besides being one of the metabolic products of acephate, MT is a systemic insecticide and acaricide. It is still used in developing countries, on some crops such as wheat, soybeans, potatoes, citrus fruits, cotton, and maize (Maroni et al, ; Araoud et al, ; Lugokenski et al, ; Uriostegui‐Acosta et al, ). World Health Organization (WHO) classified the technical product as Class 1B “Highly Hazardous,” and an Acceptable Daily Intake (ADI) of 0.004 mg/kg body weight was established by the Joint Meeting on Pesticide Residues (Maroni et al, ).…”

Short- and long-term exposure to methamidophos impairs spermatogenesis in mice

“…fungicide carbendazim appears to target pachytene spermatocytes and spermatozoa at step 14 of spermatid differentiation at the time of first exposure [31]. Damage to the sperm DNA of mice treated intraperitoneally with MET at doses of 3.75-7.0 mg.kg −1 for 4 days has been observed [16,17].…”

“…Our analyses showed that MET administration caused significant epididymal changes. In fact, Urióstegui-Acosta et al [16] reported that the epididymis and epididymal sperm cells are targets of MET toxicity. It is possible, therefore, that the sperm transit reduction in the caput/ corpus epididymis in MET-treated mice in the short-term exposure group is a result of excess ACh in mAChR.…”

“…MET exposure has also been shown to be a factor in some reproductive disorders. Deleterious effects on male reproductive endpoints such as testosterone levels, semen quality [14,15] and ADN sperm [16,17], leading to infertility and/or structural and functional changes [9,15] have also been reported. These reproductive changes caused by contact with MET may compromise the survival of the exposed species.…”

El Glufosinato De Amonio Altera La Calidad Y El Adn De Los Espermatozoides De Ratón

“…Estos compuestos son ampliamente utilizados en México y actualmente el GLA es uno de los herbicidas más empleados en algunas áreas del país, representando un problema de salud pública (Pérez-Herrera et al 2008, Rojas-García et al 2011, Urióstegui-Acosta et al 2014b. El GLA ha sido estudiado por sus efectos embriogénicos, dismorfogénicos y teratogénicos, así como por su capacidad de inducir partos prematuros y abortos en hembras expuestas experimentalmente (IPCS, 1999, Schulte-Hermann et al 2006.…”