Environmental analysis, health and toxicology最新文献

Earthworms are the most abundant invertebrates in the soils and are permanently in close contact with soil particles. Therefore, they are significantly affected by the pollutants that reach the soil system. The study was aimed at evaluating the effect of exposure to crude oil contaminated soil on Eisenia fetida using cellular antioxidant enzymes and tissue organization as biomarkers. E. fetida were exposed to different concentrations of crude oil contamination of 1 mL, 2 mL. and 3 mL (0.25, 0.50 and 0.75%) for 14 days. The antioxidant/oxidant parameters were analysed in the muscle and liver tissues. The results showed that only the reduced glutathione (GSH) of earthworms exposed to 1 mL were not significant (p>0.05) from the control, while the other concentrations (2 mL - 0.50% and 3 mL - 0.75%) were significantly different (p<0.05) from the control. The activity of catalase (CAT) with respect to the total protein content was highest in the liver of earthworms exposed to 1 mL (0.25% conc.) on day 7 (51.84 µ mol/mg pro) while the least CAT activity with respect to the total protein content was reported in the liver of control earthworms after 14 days (19.51 µ mol/mL/min). A significant increase in the activity of superoxide dismutase at all the concentrations (0.25, 0.50 and 0.75%) after 14 days were also observed. Significant histopathological alterations were observed in E. fetida from the three concentrations. Severe disruptions in the arrangement of their body wall muscle layers, distorted internal viscera, as well as cellular degeneration, pigments, moderate to severe areas of lesion, and distortion of the shape of circular and longitudinal muscles, eroding of internal and external tissues leading to total destruction of body wall were observed. In conclusion, the study revealed that crude oil even at lower concentration induced biomarker responses in E. fetida such as higher levels of Malondialdehyde in E. fetida after exposure crude oil due its toxicity. Histopathological alterations such as cellular degeneration, moderate to severe areas of necrosis, areas of inflammation, inclusion bodies, pigments, and distortion of the shapes of circular and longitudinal muscles also showed the adverse impacts of crude oil pollution in the soils.

The present work is carried out to explore the neuroprotective potential of Melatonin(Mel), on Ni-induced neurobehavioral, biochemical and histological alterations in male and female rats. The rats were intraperitoneally administered by nickel chloride (NiCl2, 1 mg/kg) and Mel (4 mg/kg) for 60 days. A neurobehavioral assessment was performed. Biochemical determinations of oxidative stress (OS) levels, and histological analysis of hippocampal tissues were also performed. Results showed that Nickel (Ni) treatment increased anxiety-like and depression-like behavior in rats. Besides, cognitive behavior on the Morris water maze was compromised following Ni treatment. Alongside this, Ni elevated hippocampal OS markers like lipid peroxidation and nitric oxide formation with a decrease in superoxide dismutase and catalase activities. Histological observations confirmed these results. Significantly, Mel administration alleviated neurobehavioral changes in Ni-treated rats of both genders. Also, Mel attenuated Ni-induced OS and increased the activities of antioxidant enzymes. The histopathological studies in the hippocampus supported that Mel markedly reduced the Ni-induced neuronal loss. In conclusion, this study suggests that Mel has a neuroprotective effect against Ni-induced neurobehavioral alterations, which may be related to lowering OS in the hippocampus.

This study investigated the neurotoxic effects of permethrin on the cerebellum, hippocampus and prefrontal cortex of Wistar rats and its effects on some behavioral patterns. Fifteen adult male Wistar rats were grouped into three categories: Group A received 0.1 mL normal saline (control), and Groups B and C received mixed feed with 500 mg/kg and 1,000 mg/kg of 0.6% permethrin, respectively, for 14 days. The animals were assessed for memory, anxiety and exploratory locomotion and thereafter anesthetized and transcardially perfused with normal saline and 4% paraformaldehyde (PFA). Cerebellum, hippocampus and prefrontal cortex were excised from the whole brain and processed for tissue histology, histochemistry and immunohistochemistry. Oxidative status and lipid peroxidation were also assessed using catalase, glutathione peroxidase, superoxide dismutase and malondialdehyde as biomarkers. Results revealed dosedependent decrease in body weights but increase in cerebellar and prefrontal weights, depletion of endogenous antioxidant markers, cognitive deficits, reduced locomotor activities, degenerative changes in the microarchitecture at high doses and presence of chromatolytic cells at both low and high doses of permethrin. Astrocytes were activated while synaptophysin expression was downregulated. Permethrin causes dose-dependent neurotoxicity on the morphology, neurochemistry and oxidative status of different brain regions, and these could affect behavioral performance and other neurologic functions.

There has been growing concern over the effects of heat waves on health. However, the effects of heat waves on the health of individuals in vulnerable groups have rarely been examined. We aimed to investigate the acute health effects of heat waves in elderly individuals living in rural areas and to survey their adaptation capacity. Repeated measurements of body temperature (BT), blood pressure, sleep disturbance, and indoor temperature were conducted up to six times for each of 104 elderly individuals living in rural areas of South Korea during the 2018 heat wave. Changes in BT, systolic blood pressure (SBP), and diastolic blood pressure (DBP) according to variations in indoor and outdoor temperature were analyzed using linear mixed effect models controlling for age, sex, smoking, and drug use. We also surveyed heat wave adaptation capacity, heat wave shelters, and self-reported health problems. The average indoor temperature measured during the study period was 30.5°C (range: 22.9-38.3°C) and that of ambient temperature was 30.6°C (range: 24.6-36.3°C). BT significantly increased with indoor and outdoor temperatures. The effect on BT was greater in elderly women and the elderly with hypertension. DBP generally decreased with increasing indoor temperature, though the correlation was only statistically significant among the elderly with hypertension. Only 22 (21.2%) individuals used air conditioners during the heat wave. Most did not use an air conditioner mainly to avoid high electricity costs. Of the participants, 58.7% reported experiencing sleep disturbance, which was the most frequent self-reported health problem. Elderly individuals living in rural areas are directly exposed to high temperatures during heat waves, and their vital signs are sensitive to increases in indoor temperature due to poor adaptation capacity. Well-designed strategies for alleviating health-related stress during heat waves are necessary.

The Kolleru Lake, India is a famous wetland of international significance. Analyses of certain potentially toxic heavy metal ions in water indicate that this freshwater lake is characterized by highly heterogeneous distribution of chromium (Cr; 4.5‒80 μg/L), copper, iron (Cu, Fe; below detection limit), manganese (Mn; 1‒313 μg/L) and zinc (Zn; below detection limit). Non-carcinogenic health risk assessment indices like hazard quotients (HQ) and hazard indices (HI) are estimated following the guidelines recommended by the US Environmental Protection Agency (USEPA). These indices are found to be within the acceptable limit (<1), indicating negligible potential health risk via ingestion and dermal routes. However, when the average values of these indices pertaining to the Kolleru lake are normalized with similar estimates from clean and uncontaminated global surface water, both high and low ratios are obtained. While Cr (12.5), Cu (2.3) and Mn (3.7) exhibit high ratios, those of Fe (0.09) and Zn (0.99) show respectively low and comparable values. The significance of such heterogeneous distribution of hazard indices and their ratios are discussed. Further, average carcinogenic risk levels of the adults and children due to Cr ingestion are estimated to be 0.00154 and 0.0022, respectively. Both values are higher than the permissible levels recommended by the USEPA. As a remediation measure, it is recommended that monitoring the levels of heavy metal in water and other items like fish in the lake or rice and vegetables grown in the area is needed to be carried out at regular intervals. This study therefore offers requisite perception to the local government and health officials to evolve their plan of action so that effective management and mitigation of water quality of the Kolleru lake can be administered.

Non-target aquatic organisms such as fish may be impacted by agricultural activities through the run-off of pesticides from farms into aquatic ecosystems. In this study, the genotoxic (erythrocytic micronuclei) and histological effects of sublethal concentrations (1% and 10% of 96-h median lethal concentration (LC50) values) of two pesticides (dichlorvos and paraquat) were evaluated in Clarias gariepinus (the African Sharptooth Catfish) for 28 days. The 96-h LC50 of dichlorvos and paraquat against fingerlings of C. gariepinus was 730 µg/L and 50 µg/L, respectively. There was a significant dose-dependent increase (p<0.05) in micronuclei in the erythrocytes of exposed C. gariepinus (2.00±0.82 ‰ to 3.25±1.26 ‰ for dichlorvos and 2.25±0.96 ‰ to 4.75±0.96 ‰ for paraquat) compared to control (0.75±0.96 ‰) by day 28. Gill histological alterations such as mild to severe necrosis and blunting of secondary lamellae were observed in C. gariepinus exposed to higher sublethal concentrations of both pesticides. This study showed that non-target aquatic organisms like C. gariepinus may be at risk of adverse biological effects from exposure to pesticides from non-point sources. We recommend environmental monitoring and sensitization on responsible pesticide use to stakeholders. This will forestall potential adverse ecological effects in aquatic ecosystems.

The emergence and rapid spread of antibiotic-resistant bacteria due to unethical and non-scientific disposal of hospital wastes and clinical by-products caused an alarming environmental concern and associated public health risks. The present study aims to assess the co-selection of antibiotic resistance and heavy metal tolerance by bacteria isolated from hospital effluents. These isolates were also tested for hemolytic activity, pH-tolerance, thermal inactivation, auto-aggregation, cell-surface hydrophobicity and interaction with other bacteria. The study reports the prevalence of antibiotic-resistant and heavy metal tolerant bacteria in clinical effluents and water samples. Most of these isolates were resistant to vancomycin, clindamycin, ampicillin, rifampicin, penicillin-G, methicillin and cefdinir, and evidenced the production of extended-spectrum β-lactamase enzyme. Toxic metals such as cadmium, copper, iron, lead and zinc also exert a selection pressure towards antibiotic resistance. Pseudomonas aeruginosa strain GCC_19W3, Bacillus sp. strain GCC_19S2 and Achromobacter spanius strain GCC_SB1 showed β-hemolysis, evidenced by the complete breakdown of the red blood cells. Highest auto-aggregation was exhibited by Bacillus sp. strain GCC_19S2; whereas, maximum cell-surface hydrophobicity was displayed by P. aeruginosa strain GCC_19W1. Antagonistic activity by Stenotrophomonas maltophilia strain GCC_19W2, P. aeruginosa strain GCC_19W3 and strains of Achromobacter restricts the growth of other microorganisms by producing some bactericidal substances. The study emphasises undertaking safety measures for the disposal of clinical effluents directly into the environment. The study suggests adopting necessary measures and regulations to restrict the spread of emerging pathogens within the hospital biome and community, which if unnoticed, might pose a significant clinical challenge.

The purpose of this study was to evaluate the relationship between farmer's syndrome and neurotoxic symptoms in farming couples. The study was conducted on 348 farmers (174 couples) in Chungnam Province of South Korea. We obtained information on general and agricultural characteristics, farmer's syndrome, and neurotoxic symptoms through face-to-face surveys from 2014 to 2019. The Korean version of the diagnostic standard scale was used for farmer's syndrome, and the Swedish Q16 questionnaire was used for neurotoxic symptoms. Logistic regression analysis was used to identify neurotoxic symptoms affected by farmer's syndrome. The prevalence of 'positive' neurotoxic symptoms was higher in wives (72.4%) than in husbands (56.9%). Compared with husbands with 'negative and probable' farmer's syndrome (reference), husbands with 'positive' farmer's syndrome were more likely to have 'positive' neurotoxic symptoms (odds ratio [OR] = 5.37, 95% confidence interval [CI] = 2.01-14.30). Compared with wives with 'negative and probable' farmer's syndrome (reference), wives with 'positive' farmer's syndrome were more likely to have 'positive' neurotoxic symptoms (OR = 7.07, 95% CI = 2.58-19.38). Therefore, neurotoxic symptoms in both husbands and wives were significantly associated with farmer's syndrome. However, wives had a higher risk of neurotoxic symptoms than husbands. The findings of this study might be useful as important data for establishing and training agricultural safety and health policy.

There is currently no governmental body in South Korea resembling the type of poison center (PC) recommended by the World Health Organization (WHO). All Organization for Economic Cooperation and Development (OECD) member countries except for South Korea maintain such a PC tasked with both preventing poisoning accidents and supporting the prompt treatment of poisoned patients. Such a PC could very possibly have allowed the country to more promptly recognize the widespread wave of humidifier disinfectant (HD) associated health effects, including fatal lung injury and death, that lasted started roughly in 2000 and continued through 2011. Despite this chemical poisoning tragedy, South Korea still lacks a surveillance system to monitor health effects caused by the use and consumption of materials that include products containing chemicals, foodborne pathogens, drugs, pesticides, etc. There have been no legal procedures for examining the potential risk of products or materials manufactured by industry. The reporting of national poisoning data or causes of poisoning, which is near ubiquitous in advanced countries with a PC, has not taken place We recommend that a PC should be established within the Korea Disease Control and Prevention Agency (KDCA). In addition, in order to perform surveillance of poisoning cases across the country, a certain number of regional PCs, including at large hospitals, will also be necessary.