Environmental Toxicology and Chemistry最新文献

Rivers and other surface waters worldwide receive thousands of chemicals from diverse sources, including road runoff. We identified more than 170 chemicals that have been associated with road runoff across published literature that derive from tyre wear, exhaust emissions, and brake pad abrasion, amongst other sources. The impact of these chemicals on aquatic organisms however is poorly understood. Addressing this knowledge gap for U.K. surface drains, we first analysed the available literature studies on road run-off (23) to determine the concentrations of 70 chemicals in road run off monitored in surface drains by the U.K. Environment Agency over 25 years (between the years 2000 and 2024). We show 43 of the 70 monitored chemicals in U.K. surface drains exceed reported minimum concentrations and 19 the highest measured concentrations across existing literature. Twenty of the monitored chemicals exceeded the lowest effect concentration for 50% lethality (LC50) in fish and/or aquatic invertebrates. These findings suggest that road-runoff chemicals in U.K. surface drains pose a potential risk to aquatic life, but their impacts will depend upon other factors including their dilution levels in rivers.

The presence of lead (Pb) sinkers and jigs lost to waterbodies from recreational fishing serves as a potential risk to aquatic ecosystem health. Assessing the toxicity of Pb released from fishing gear poses several challenges, and one proposed approach is to use Pb salts as a surrogate. However, it remains unclear how the toxicity of Pb salts compares to that of Pb derived directly from fishing gear. To test this, we measured Pb release from different concentrations of fishing sinkers (e.g., bell sinkers and split shot sinkers), at 4ᵒC and 30ᵒC for 48 hr. Further, we compared the overt toxicity of Pb sinkers and jigs against lead nitrate (Pb(NO3)2) toxicity using Daphnia magna. Water Accommodated Fractions (WAF) were generated by suspending Pb sinkers (100 g/L) in water for 48 hr, which caused Pb dissolution exceeding Water Quality Guidelines by ∼35-100x with additional impurities of zinc and cadmium in both the split shot and bell sinkers, as well as iron, arsenic, nickel, copper in the bell sinkers. These sinker types were not acutely toxic to D. magna, however chronic exposure to WAFs released from both types of sinkers significantly impacted reproduction (number of neonates produced over 21 days per D. magna) and growth. Therefore, discarded fishing gear may represent a notable source of environmental Pb as well as other metals. This study offers valuable baseline data to support future discussions on regulating Pb-based fishing gear in Canada and highlights the importance of developing cost-effective alternatives.

Agricultural and urban waste contains various contaminating substances that reach rivers and bodies of water daily. Anthropogenic activities threaten the integrity of aquatic ecosystems and the resident species. Hypostomus ancistroides is a neotropical fish part of the South American fauna. Due to their benthic habit and trophic niche, these organisms can be directly exposed to mutagenic pollutants. Therefore, this study aimed to investigate the toxicity of urbanized and rural river waters (Toledo River, Toledo, Paraná, Brazil) by evaluating the genotoxic and biochemical effects in H. ancistroides. Fish were collected at two urbanized points on the Toledo River (P1-urban; P2-urban and rural-influenced) and at one point on the Santa Quitéria River (P3), located in the rural area of Toledo. The frequency of micronuclei (MNs), erythrocyte nuclear abnormalities (ENAs), and biochemical biomarkers (superoxide dismutase, SOD; catalase, CAT; glutathione S-transferase, GST; and lipid peroxidation, LPO) were analyzed across two seasons (summer and winter). Micronuclei and ENAs were observed in H. ancistroides specimens both in urban and rural areas, with the highest occurrence in P2 during the winter. Concerning biochemical biomarkers, H. ancistroides showed a significant increase in SOD during summer in P2 but no significant difference in CAT. Lipid peroxidation during winter in P2 and P3 was higher than in P1 during summer. Higher GST activity was observed in the specimens in P1 and P2 during winter. Both rivers suffer from the impact and contamination caused by human activities, especially during winter. Still, the greatest genotoxicity was observed in P2, indicating a high risk of contamination to the aquatic organisms inhabiting the local area.

The release of heavy metals from commercial deep-sea mining is likely to be a long-term process lasting decade, and therefore fish communities are actually exposed to a chronic, ongoing stressor. However, toxicity assessment data for marine fishes related to heavy metals have predominantly been derived from acute toxicity experiments to date. To evaluate this potential risk, this study selected four heavy metals (Cu2+, Cd2+, Mn2+, VO4³-) and with potential for release from deep-sea mining and determined their 14-day median lethal concentration (LC50) for embryos and 96 hour (96 hr) LC50 for newly hatched larvae of marine medaka. Subsequently, a 60-day low-concentration, long-term exposure experiment was conducted based on the 96 hr LC50 of Cu2 + and Cd2 + for larvae. This experiment measured parental reproductive indices, such as spawning output and fertilization rate, and offspring developmental parameters, including hatching rate, malformation rate, hatching delay rate, and egg diameter, under stress from Cu2 + and Cd2 + at concentrations of 1/25 or 1/5 of 96 hr LC50. The results indicated that at long-term exposure concentrations even as low as 1/25 of 96 hr LC50 (Cu2+: 0.36 mg L-1, Cd2+: 0.25 mg L-1), both parental reproductive capacity and offspring development were significantly inhibited. This was manifested by an approximately 20% decrease in parental spawning output, a 5-14% reduction in offspring hatching rate, a 12-29% increase in hatching delay rate, alongside significant elevations in malformation rate and heart rate. In contrast, the impact on fertilization rate was relatively minor. These findings demonstrate that marine medaka are more sensitive to the long-term stress induced by heavy metals compared to short-term acute exposure, particularly regarding key indicators related to population recruitment such as parental reproductive fitness and offspring development. This study provides long-term toxicological data under stress conditions, so far largely lacking, for establishing environmental impact assessment thresholds for deep-sea mining activities.

The bisamide insecticides occupy a huge market share in the pesticide market, and are commonly used in the intergrated rice fish farming system. Most especially chlorantraniliprole (CAP) has been frequently used and detected in fish tissues. The 96 hr LC50 of seven bisamide insecticides including tetrazoliumamide, fluorobenzamide, cyantraniliprole, tetrachloropamide, chlorantraniliprole, cyclobromides, trifluorobenzine for fish, crab and shrimp, closed shell, zooplankton and phytoplankton were determined. Results showed 96 hr LC50 for fish, crab and shrimp, closed shell, zooplankton and phytoplankton were 0.003∼5.263 mg·L-1, 0.0001∼1.562 mg·L-1, 0.010∼1.526 mg·L-1, 0.0004∼0.064 mg·L-1, respectively. Effects of 1.5 μg·L-1 CAP on enzymatic activities and its gene expressions in juvenile American shad were simultaneously determined. TNF - α and caspase - 9 (except for 96 hr), IFN - γ and IL - 10 were significantly increased and decreased, il1b significantly increased. The pathways of apoptosis, cytokine-cytokine receptor interaction, ferroptosis, MAPK signaling pathway, oxidative phosphorylation, p53 signaling pathway, TGF - β signaling pathway were significantly enriched in the comparisons at 96 and 192 hr. CAP induced changes of enzymatic activities of inflammatory cytokines, gene expression profiles involving oxidative stress, apoptosis, and immune dysregulation in aquatic organisms.

The overuse of organophosphorus pesticides (OPPs) has adverse effects on the environment and human health in China. To fully understand the distribution of multiple OPPs in suburban watersheds and their potential ecological impacts, this study selected two watersheds in East China. A total of 41 OPPs were observed by the Hi-volume Solid Phase Extraction (SPE) technique. In general, the mean OPP concentrations in the two watersheds were higher in wet season (26.51 ng/L) than dry season (17.52 ng/L). Famphur, bromfenvinphos and chlorfenvinphos were the most common pollutants with their detection rates all above 83% in the study area. Among the 14 highly detected OPPs, famphur and parathion were the dominated compounds in dry season and wet season, respectively. The highest total concentrations of OPPs were observed around the farmlands and planting lands, which indicated that the distribution of OPPs were closely related to the use of pesticides. Parathion, parathion-methyl, fenthion and famphur were commonly detected in China, which were markedly different from those in other countries. According to the corresponding analysis, there was a strong correlation between formothion and dimethoate in dry season. Parathion and mevinphos had a strong relationship in wet season. The total risk quotient values of the parathion and fenitrothion were all above 1, which indicated that they might cause high ecological risks in the two watersheds. The average daily dose in wet season was nearly twice that of dry season both in the two watersheds, and methyl parathion, chlorfenvinphos and bromfenvinphos were the main contributors. The total HIs in the two watersheds (3.90 × 10-3 and 4.90 × 10-3) were both under an acceptable health risk.

A comprehensive picture of the environmental risks posed by pharmaceuticals in Japan remains unclear, primarily because of the limited availability of toxicity data related to the number of pharmaceuticals prescribed or detected in aquatic environments. To understand the environmental risk, we first compiled toxicity data from the literature, focusing on chronic toxicity. For compounds for which no published information is available, we conducted (sub-)chronic toxicity tests at three trophic levels. We obtained toxicity data, mainly chronic toxicity data, for > 75 pharmaceutical compounds. Combining these data with the results of nationwide monitoring surveys of rivers and lakes in Japan, we conducted a comprehensive environmental risk assessment of > 75 pharmaceuticals. The results showed that roxithromycin (a macrolide antibiotic) exhibited high toxicity to algae, whereas teprenone (antipeptic ulcer agent), ticlopidine (anticoagulant), and eperisone (muscle relaxant) showed high toxicity to daphnids. Fewer pharmaceuticals have demonstrated similarly high toxicity to fish. Among the selected pharmaceuticals, macrolide antibiotics pose the highest environmental risk, though they present only a moderate risk to algae, with certain compounds exceeding a toxic unit value of 0.1. For daphnids, environmental risks of diverse pharmaceuticals were relatively high but the toxic unit values were at most approximately 0.1, indicating moderate or low risk. The environmental risk to fish was generally lower than that to algae and daphnids. The sum of the toxic units indicated that the highest value for algae exceeded 1. This suggests that pharmaceutical contamination poses a significant risk to the aquatic environment in some locations in Japan.

Human influence on Antarctic marine ecosystems is a growing concern, despite limited available information. In this study, we assessed the effects of anthropogenic pollution on free-living nematode community structure around Casey Station, East Antarctica. Sediment samples were collected from six locations impacted by human activities, Wharf (WH), Wilkes (WI), Brown Bay Inner (BBIN), Brown Bay Middle (BBMID), Brown Bay Outer (BBOUT), and Shannon (SH), and four reference locations, O'Brien Bay (OB1, OB2, OB3) and McGrady Cove (MCG). Nematode communities differed significantly between locations, correlating with higher pollutant concentrations (metals and persistent organic pollutants) at impacted locations, and also with finer sediments with higher organic content. The reduction of taxonomic, diversity, and functional parameters, as well as the dominance of opportunistic genera and the low Ecological Quality (EcoQ) status scores in the impacted locations suggest an environment stressed by organic enrichment, possibly linked to anthropogenic activities. The results reinforce the value of marine nematodes as bioindicators and contribute to the understanding of the impact of pollution on the biodiversity of these organisms in Antarctic coastal ecosystems.

Per- and polyfluoroalkyl substances (PFAS) are a large group of anthropogenic chemicals. Due to their chemical properties, they are used heavily in commercial goods. However, these same properties that make them highly favorable for manufacturing make them extremely mobile, persistent, and resistant to breakdown in the aquatic environment. While PFAS research has historically focused on model organisms, understanding the effects of PFAS on non-model aquatic organisms is critical to best protect vulnerable species. Bivalves are aquatic organisms that provide many commercial and ecological benefits. It is essential to assess the effects of PFAS on bivalves to evaluate their potential as bioindicators in PFAS-contaminated areas as well as preserving the ecosystem services they provide. The overall objective of the current review is to is to further examine the impacts observed in bivalves exposed to PFAS as well as determining gaps in knowledge and providing recommendations for future studies. Studies have shown that PFAS structure can significantly alter the bioaccumulation potential of PFAS oftentimes with longer chain lengths yielding higher bioaccumulation factors. While overt toxicity is observed in bivalve larvae and embryos, most effects associated with PFAS exposure in bivalves is sublethal with effects ranging from oxidative stress, immunotoxicity, genotoxicity, and alterations to lipid and carbohydrate metabolism and xenobiotic metabolism. With over 9,000 PFAS, effects do differ between PFAS as a result of the structure-function relationship in addition to different effects seen across bivalve species, further highlighting the need to assess multiple PFAS as well as bivalves to best determine the potential effects of exposure. This is apparent in the need for mixture studies in addition to singular PFAS exposures as aquatic systems are not closed systems. All this to say, this review highlights the current knowledge on the bioaccumulation and toxicity of PFAS in bivalve species.