Temephos Decreases Sperm Quality and Fertilization Rate and Is Metabolized in Rat Reproductive Tissues at Low-Dose Exposure.

Temephos is an organophosphorus pesticide used in control campaigns against vectors that transmit diseases, including dengue, a public health concern. The WHO classifies temephos in category III and its safe concentration (low-observable-adverse-effect level) in male rats is 100 mg/kg/day for up to 44 days. Temephos inhibits acetylcholinesterase (AChE) and is metabolized in different tissues, probably by mixed-function oxidases; one of its metabolites is bisphenol S (BPS), which is considered an endocrine disruptor.

Methyl parathion causes genetic damage in sperm and disrupts the permeability of the blood-testis barrier by an oxidant mechanism in mice.

Methyl parathion (Me-Pa) is an extremely toxic organophosphorus pesticide still used in developing countries. It has been associated with decreased sperm function and fertility and with oxidative and DNA damage. The blood-testis barrier (BTB) is a structure formed by tight junction (TJ) proteins in Sertoli cells and has a critical role in spermatogenesis.

Oxidative stress and genetic damage among workers exposed primarily to organophosphate and pyrethroid pesticides.

The indiscriminate use of pesticides in agriculture and public health campaigns has been associated with an increase of oxidative stress and DNA damage, resulting in health outcomes. Some defense mechanisms against free radical-induced oxidative damage include the antioxidant enzyme systems. The aim of this study was to determine the levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and the relationship of antioxidant enzyme levels with DNA damage among sprayers (workers) occupationally exposed to pesticides.

Increased methylation of repetitive elements and DNA repair genes is associated with higher DNA oxidation in children in an urbanized, industrial environment.

DNA methylation in DNA repair genes participates in the DNA damage regulation. Particulate matter (PM), which has metals and polycyclic aromatic hydrocarbons (PAHs) adsorbed, among others has been linked to adverse health outcomes and may modify DNA methylation. To evaluate PM exposure impact on repetitive elements and gene-specific DNA methylation and DNA damage, we conducted a cross-sectional study in 150 schoolchildren (7-10 years old) from an urbanized, industrial area of the metropolitan area of Mexico City (MAMC), which frequently exhibits PM concentrations above safety standards.

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

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.

Sperm chromatin alteration and DNA damage by methyl-parathion, chlorpyrifos and diazinon and their oxon metabolites in human spermatozoa.

Extensive use of organophosphorous pesticides (OP) by young men represents a public health problem. Toxicity of OP mainly results in neurotoxicity due to their oxygen analogues (oxons), formed during the OP oxidative activation. OP alter semen quality and sperm chromatin and DNA at different stages of spermatogenesis.