Acute and single repeated dose effects of low concentrations of chlorpyrifos, diuron, and their combination on chicken

The neonicotinoid, imidacloprid, disrupt the chicken sperm quality through calcium efflux

Imidacloprid (IMI), an insecticide from the neonicotinoid group widely used in agriculture, has drawn attention due to its potential harmful effects on non-target species, including bird populations. In the present work, we investigated the effect of IMI on avian semen by in vitro exposure of rooster spermatozoa to this pesticide. The semen was collected twice a week. Samples collected on one day were pooled and incubated with the following IMI concentrations: 0 mM, 0.5 mM, 5 mM, 10 mM, and 50 mM at 36°C for 3 h. Comprehensive semen analysis was carried out after 1 h and 3 h of incubation, evaluating sperm motility parameters with the CASA system and using flow cytometry to assess membrane integrity, mitochondrial activity, acrosome integrity, chromatin structure, intracellular calcium level and apoptosis markers such as: early apoptosis and caspase activation and lipid peroxidation. The results of the first experiment suggest that low concentrations of IMI have a different effect on sperm motility compared to higher concentrations. In IMI samples, we also observed a lower percentage of cells with a high level of calcium ions compared to the control, and a lower level of lipid peroxidation. We concluded that IMI may act as a blocker of calcium channels, preventing the influx of these ions into the cell. To confirm this mechanism, we conducted a second experiment with calcium channel blockers: SNX 325, MRS-1845, and Nifedipine. The results of this experiment confirmed that the mechanism of action of IMI largely relies on the blockade of calcium channels in rooster sperm. Blocking the influx of calcium ions into the cell prevents the formation of Ca²⁺-dependent pores, thereby preventing an increase in cell membrane permeability, ultimately blocking early apoptosis and lipid peroxidation in chicken spermatozoa.

Diuron-induced fetal Leydig cell dysfunction in in vitro organ cultured fetal testes

Diuron is a phenylurea herbicide widely used in the agricultural industry. In recent years, the risk of infertility and developmental defects has increased due to exposure to environmental pollutants. In this study, we investigated the toxicity of diuron in fetal mouse testes using three-dimensional organ cultures. Fetal testes derived from embryonic day (E) 14.5 were cultured with 200 µM diuron for 5 days. The results revealed that diuron did not impair fetal germ cell proliferation or the expression levels of germ cell markers such as Ddx4, Dazl, Oct 4, Nanog, Plzf, and TRA 98. Similarly, the gene or protein expression of the Sertoli cell markers Sox9 and Wt1 in diuron-exposed fetal testes did not change after 5 days of culture. In contrast, diuron increased fetal Leydig cell markers (FLC), Cyp11a1, Cyp17a1, Thbs2, and Pdgf α, and decreased adult Leydig cell (ALC) markers, Sult1e1, Hsd173, Ptgds, and Vcam1. However, 3-βHSD, an FLC and ALC marker, was consistently maintained upon exposure to diuron in fetal testes compared to non-treated groups. In conclusion, our study demonstrates that diuron negatively impacts Fetal Leydig cell development, although it does not affect germ and Sertoli cells.

Chlorpyrifos Occurrence and Toxicological Risk Assessment: A Review

Chlorpyrifos (CPF) was the most frequently used pesticide in food production in the European Union (EU) until 2020. Unfortunately, this compound is still being applied in other parts of the world. National monitoring of pesticides conducted in various countries indicates the presence of CPF in soil, food, and water, which may have toxic effects on consumers, farmers, and animal health. In addition, CPF may influence changes in the population of fungi, bacteria, and actinomycete in soil and can inhibit nitrogen mineralization. The mechanisms of CPF activity are based on the inhibition of acetylcholinesterase (AChE) activity. This compound also exhibits reproductive toxicity, neurotoxicity, and genotoxicity. The problem seems to be the discrepancy between the actual observations and the final conclusions drawn for the substance's approval in reports presenting the toxic impact of CPF on human health. Therefore, this influence is still a current and important issue that requires continuous monitoring despite its withdrawal from the market in the EU. This review traces the scientific reports describing the effects of CPF resulting in changes occurring in both the environment and at the cellular and tissue level in humans and animals. It also provides an insight into the hazards and risks to human health in food consumer products in which CPF has been detected.

Persistence behavior of chlorpyrifos and biological toxicity mechanism to cucumbers under greenhouse conditions

Chlorpyrifos, a broadly utilized insecticide, inhibits many cellular and physiological processes in plants. Here, the phyto-toxicity of chlorpyrifos on cucumber plants, as well as the dissipation kinetics of chlorpyrifos in leaves, were investigated. Those results showed that chlorpyrifos accumulated primarily in the leaves under normal agrochemical spraying conditions with the half-lives among 2.48-4.59 days. Residues of the primary metabolite, 3,5,6-trichloro-2-pyridinol (TCP), rapidly accumulated in plant tissues and soil with chlorpyrifos degradation. The application amount of chlorpyrifos had a significant effect on the persistence of chlorpyrifos and TCP in both plant and soil environments. Chlorpyrifos generated excessive reactive oxygen species (ROS) and malondialdehyde (MDA), which led to oxidative damage. High chlorpyrifos stress even inhibited antioxidant enzymes. The photosynthetic system and gas exchange were suppressed, which ultimately lead to inefficient light use under chlorpyrifos stress. Morphological results revealed that chlorpyrifos induced membrane damage and harmed organelles such as mitochondria and chloroplast. Noninvasive micro-test technology (NMT) showed that chlorpyrifos promoted intracellular Ca²⁺ influx and efflux of H⁺ and K⁺. The Ca²⁺ influx was significantly stimulated after both high and low chlorpyrifos treatment with the minimum value of - 336.33 pmol·cm^-2·s^-1 at 258 s and - 155.68 pmol·cm^-2·s^-1 at 288 s, respectively. Chlorpyrifos stress reversed the H⁺ influx to an efflux in cucumber mesophyll with the mean value of 0.45 ± 0.03 pmol·cm^-2·s^-1 and 0.19 ± 0.03 pmol·cm^-2·s^-1 in cucumber plants under low and high chlorpyrifos stress. High chlorpyrifos stress dramatically increase K⁺ efflux in cucumber leaves by 13.68 times higher than the control. We suggest that ion homeostasis destruction, accompanied by ROS, resulted in oxidative damage to the mesophyll cell of cucumber seedlings.

Cardiotoxicity of some pesticides and their amelioration

Pesticides are used to control pests that harm plants, animals, and humans. Their application results in the contamination of the food and water systems. Pesticides may cause harm to the human body via occupational exposure or the ingestion of contaminated food and water. Once a pesticide enters the human body, it may create health consequences such as cardiotoxicity. There is not enough information about pesticides that cause cardiotoxicity in the literature. Currently, there are few reports that summarized the cardiotoxicity due to some pesticide groups. This necessitates reviewing the current literature regarding pesticides and cardiotoxicity and to summarize them in a concrete review. The objectives of this review article were to summarize the advances in research related to pesticides and cardiotoxicity, to classify pesticides into certain groups according to cardiotoxicity, to discuss the possible mechanisms of cardiotoxicity, and to present the agents that ameliorate cardiotoxicity. Approximately 60 pesticides were involved in cardiotoxicity: 30, 13, and 17 were insecticides, herbicides, and fungicides, respectively. The interesting outcome of this study is that 30 and 13 pesticides from toxicity classes II and III, respectively, are involved in cardiotoxicity. The use of standard antidotes for pesticide poisoning shows health consequences among users. Alternative safe medical management is the use of cardiotoxicity-ameliorating agents. This review identifies 24 ameliorating agents that were successfully used to manage 60 cases. The most effective agents were vitamin C, curcumin, vitamin E, quercetin, selenium, chrysin, and garlic extract. Vitamin C showed ameliorating effects in a wide range of toxicities. The exposure mode to pesticide residues, where 1, 2, 3, and 4 are aerial exposure to pesticide drift, home and/or office exposure, exposure due to drinking contaminated water, and consumption of contaminated food, respectively. General cardiotoxicity is represented by 5, whereas 6, 7, 8 and 9 are electrocardiogram (ECG) of hypotension due to exposure to OP residues, ECG of myocardial infraction due to exposure to OPs, ECG of hypertension due to exposure to OC and/or PY, and normal ECG respectively.

Biochemical and molecular alterations in freshwater mollusks as biomarkers for petroleum product, domestic heating oil

To investigate the effect one of the oil products, domestic heating oil (DHO), on freshwater mollusks, Unio tigridis and Viviparous bengalensis were exposed to three DHO concentrations for each species (5.8, 8.7, and 17.4 ml L^-1 for mussels; 6.5, 9.7, and 19.5 mlL^-1 for snails, respectively). Antioxidant enzymes (superoxide dismutase, catalase), malondialdehyde, acetylcholinesterase and DNA damage in both species tissues were monitored over 21 days. The results showed that both antioxidant enzymes concentration (SOD and CAT) increased in the lowest DHO concentrations (5.8, and 8.7 ml L^-1), and then decreased in the highest concentration (17.4 ml L^-1) as the same pattern for Unio tigridis, but this not occurred for Viviparous bengalensis. MDA values recorded significantly increased compared to control. No reduction was observed in AChE concentrations in soft tissues of both mollusks may due to that DHO was a non-neurotoxicant to Unio tigridis and Viviparous bengalensis. The results of DNA damage parameters were showed significant differences (p≤ 0.05) between control and DHO concentrations except lowest concentration for each parameter measured in digestive gland of Unio tigridis. As well as, these significant differences were recorded between control and three concentrations of DHO exposure for comet length, and tail length parameters, and between control and highest oil concentration for tail moment in Viviparous bengalensis. DHO has the ability to prevent the reproduction of Viviparous bengalensis snail relation to control, that is what we considered strong evidence of the toxicity properties of DHO on the reproductive status of this species of snails. SOD, CAT, and MDA were useful biomarkers for evaluating the toxicity of DHO in mussel and snails, and comet assay was a good tool to assess the potential genotoxicity of DHO.