Environmental Toxicology最新文献

This study examines the teratogenic effects of a sublethal dose (0.1 ppm) of a combination insecticide containing 50% chlorpyrifos (CP) and 5% cypermethrin (CM) on chick embryo limb development, revealing severe skeletal abnormalities and disruptions in key molecular pathways. Early-stage defects, including reduced somite numbers and abnormal somite patterning, were observed by day 2, with prominent limb deformities, such as limb shortening and twisted digits, emerging by days 10 and 21. X-ray analysis confirmed skeletal anomalies, while Alcian blue-Alizarin red staining revealed malformed cartilage and bone structures. Gene and protein expression analyses showed significant downregulation of Sonic hedgehog (SHH), Fibroblast Growth Factors (FGF10, FGF8), and WNT7A, leading to impaired digit formation and limb elongation. HOX genes (HOXA11, HOXD11) were initially upregulated but later downregulated, disrupting limb segment identity. Additionally, downregulation of Tbx4 and Pitx1 contributed to hindlimb malformations. Dysregulation of CASPASE3 impaired apoptosis, resulting in defective digit separation. Molecular docking studies indicated strong binding affinities of CP and CM to SHH, FGF10, WNT7A, and HOX proteins, suggesting interference with these signaling pathways. Notably, the disruption of the SHH-FGF-WNT axis, essential for limb patterning, was a key driver of these defects. Biochemical assays further revealed reduced hydroxyproline content, indicating impaired collagen synthesis. These findings highlight severe disruptions in SHH, FGF, WNT, HOX, Tbx4, and Pitx1 pathways, emphasizing the need for stricter pesticide regulations to prevent congenital limb malformations.

Mushroom cultivation and traditional mushroom procurement are widespread worldwide. Therefore, it is important to determine the extent of the risk of heavy metal exposure by consuming wild edible mushrooms. The aim of this study was to determine the levels of four elemental impurities (Cd, Pb, As, and Hg) in edible mushroom species (Macrolepiota mastoidea, Bovista aestivalis, Tricholoma fracticum, Helvella sp., and Rhizopogon roseolus) collected from Çanakkale and Van regions of Türkiye and to investigate potential health risks. For elemental impurity analysis, 0.3 g dry samples of mushrooms collected in Çanakkale and Van provinces between 2022 and 2023 were weighed and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). Target hazard quotient (THQ) was calculated for non-carcinogenic risk assessment in children and adults, followed by hazard index (HI) for each mushroom. Carcinogenic risk (CR) was determined. Probabilistic total THQ and total CR in children and adults were calculated using the Monte Carlo simulation method. Cd levels in five mushroom species ranged between 11.19–4838.71 μg/kg, Pb levels between 495.43 and 2836.81 μg/kg, As levels between 3267.52 and 25823.07 μg/kg, and Hg levels between 0.00 and 1594.50 μg/kg. The non-carcinogenic risk potential of As level was observed in all mushroom samples. THQ value was found to be greater than 1. These values also affected the HI value in all mushrooms; the latter was also greater than 1. Since As was detected in all mushrooms in the study and the CR value of this risk element was at a level that may pose a potential carcinogenic hazard, a potential health risk in adults and children can be noted. Furthermore, the Monte Carlo simulation showed that the health risks due to elemental impurity accumulation in mushrooms may increase significantly in children and adults, causing serious health problems. Children are more severely affected by elemental impurity concentrations than adults, especially considering their body weight, which makes it necessary to take protective measures.

Parabens (PBs) are alkyl esters of para-hydroxybenzoic acid and are widely used in pharmaceuticals, food and beverages, and cosmetics due to their antimicrobial properties. Parabens are also known as “Endocrine disruptors” and can cause toxicity in different organisms. Parabens, especially methylparaben and propylparaben are also present in many environmental matrices, such as water sources and soil, and can cause cytotoxic and genotoxic effects in different organisms. This study aimed to evaluate the genotoxic and cytotoxic effects of the two most commonly used types of parabens that are methylparaben and propylparaben on meristematic cells in onion root tips by comet assay and cytological anomaly-based evaluation. Root growth inhibition assay was used to evaluate root growth inhibition. A. cepa assay was used to assess mitotic index (MI) and chromosomal aberrations (CAs). DNA damage was assessed by comet assay. The half maximal effective concentration (EC₅₀) on the growth of A. cepa cells calculated for methylparaben and propylparaben was 75 ug/mL (2.70 ± 0.10 cm) and 25 ug/mL (2.70 ± 0.2 cm), respectively. Similarly, dose- and time-dependent decrease in mitotic index (MI), increase in chromosomal aberrations (CAs) and increase in DNA damage were observed by the exposure of A. cepa root tips to methylparaben and propylparaben upon 24 h and 48 h exposure periods. The findings of the study showed that propylparaben is more cytotoxic and genotoxic than methylparaben as evidenced by a significant reduction in MI, along with an increase in chromosomal aberrations and DNA damage when compared to methylparaben.

This study investigated the effects of cadmium (Cd²⁺) exposure on the biochemical indexes, antioxidant responses, non-specific immune responses, inflammatory responses, anti-stress responses, and related gene expression levels of juvenile GIFT tilapia ( Oreochromis niloticus ). Four groups of juveniles were cultured for 30 days in four aquaculture waters with different levels of Cd²⁺ concentrations (0, 0.2, 0.4, and 0.6 mg/L). Key findings include: In comparison to the control group (0 mg/L Cd²⁺), cadmium stress significantly impacted the liver and serum biochemical indices of juvenile tilapia (p < 0.05). The activities of catalase (CAT), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC) in the gills, liver, and serum were significantly decreased (p < 0.05) and the contents of malondialdehyde (MDA) showed the opposite trend. The expression levels of interleukin-10 (IL-10), sonic hedgehog (SHH), and cytochrome oxidase 1A (CYP1A) were significantly down-regulated (p < 0.05) and the expression levels of interleukin-1β (IL-1β), tumor necrosis factor α (TNFα), interferon γ (IFNγ), interleukin-6 (IL-6), interleukin-8 (IL-8), transforming growth factor β1 (TGF-β1), metallothionein (MT), and heat shock protein 70 (HSP70) in the liver were significantly up-regulated (p < 0.05). In conclusion, the concentration of cadmium in aquaculture water exceeded 0.2 mg/L, and the biochemical indexes, antioxidant responses, non-specific immune responses, inflammatory responses, and anti-stress responses of juvenile GIFT tilapia were markedly altered. These findings highlight that even sub-lethal Cd²⁺ concentrations (≥ 0.2 mg/L) pose substantial risks to the physiological health and survival of juvenile tilapia.

Heavy metals (HMs) pollution in road dust has an adverse effect on human health and the environment. This study evaluates the pollution level with the different geochemical indices and the ecological and health risks of HMs pollution in the road dust of Masjed Soleyman city, Khuzestan province, Iran. The samples were collected from the main streets with different land uses of industrial, commercial, residential, and heavy traffic. The most minerals identified in dust samples were crystalline silicate and carbonate minerals. Aluminum (Al: 12730 mg/kg), iron (Fe: 10295 mg/kg), manganese (Mn: 173.25 mg/kg), and barium (Ba: 149.31 mg/kg) had the highest mean concentrations of all the land uses. Based on the geo-accumulation index (I _geo), road dust in Masjed Soleyman city was moderately to heavily contaminated with HMs such as antimony (Sb) and copper (Cu) and they were mostly from anthropogenic sources. According to the contamination indices, different classes of HMs contamination in road dust were observed. The non-carcinogenic hazard index was less than one (HI < 1) in both children and adults through all exposure pathways. The total cancer risk (TCR) indicates a possible carcinogenic risk for children. The highest value of the ecological risk index for dust samples was in the industrial area (ERI = 222.23). The cluster analysis (CA) results were consistent with the results of the correlation analysis and PCA, indicating similar sources of some HMs. Considering the health risk for children and the presence of HMs in dust samples, it is necessary to make decisions in mitigating potential risks associated with HMs pollution.

Tri-ortho-cresyl phosphate (TOCP) is a widely used organophosphorus compound in industry and agriculture, but its immunotoxicity has not been thoroughly investigated. Therefore, this study aimed to assess the immunotoxicity of TOCP in mice by examining changes in immune cell populations and histopathological alterations in the spleen. Male ICR mice were administered TOCP via daily oral gavage at doses of 200 and 400 mg/kg body weight (BW)/d for 28 days to evaluate its effects on immune cell populations in blood and spleen. TOCP treatment at 400 mg/kg BW/d reduced white blood cell counts by 18% and decreased lymphocyte counts by 10.5% compared to the control group. Specifically, CD3⁺CD4⁺ T cell counts in blood decreased by 17.4%. In the spleen, TOCP exposure reduced the proportion of T cells by 13.3%. TOCP also disrupted the structural integrity of the splenic white pulp. In vitro the TOCP metabolite cresyl saligenic phosphate (CBDP) inhibited splenic lymphocyte proliferation, selectively increasing T cell proportions by 21.25% and inhibiting B cell proportions by 13.18%, different from in vivo findings. This suggests that the reduction of T cells observed in vivo may not be solely due to direct cytotoxic effects of TOCP on T cells. These observed changes in immune cell counts and spleen histology indicate that TOCP has a systemic immunotoxicity in vivo, which could lead to compromised immune surveillance and defense function.