Environmental Health and Toxicology最新文献

Epigenetics, potentially heritable changes in genome function that occur without alterations to DNA sequence, is an important but understudied component of ecotoxicology studies. A wide spectrum of environmental challenge, such as temperature, stress, diet, toxic chemicals, are known to impact on epigenetic regulatory mechanisms. Although the role of epigenetic factors in certain biological processes, such as tumourigenesis, has been heavily investigated, in ecotoxicology field, epigenetics still have attracted little attention. In ecotoxicology, potential role of epigenetics in multi- and transgenerational phenomenon to environmental stressors needs to be unrevealed. Natural variation in the epigenetic profiles of species in responses to environmental stressors, nature of dose-response relationships for epigenetic effects, and how to incorporate this information into ecological risk assessment should also require attentions. In this review, we presented the available information on epigenetics in ecotoxicological context. For this, we have conducted a systemic review on epigenetic profiling in response to environmental stressors, mostly chemical exposure, in model organisms, as well as, in ecotoxicologically relevant wildlife species.

Several studies showed that the inflammatory and fibrotic responses induced by polyhexamethylene guanidine phosphate (PHMG-p) were similar to those observed for idiopathic pulmonary fibrosis in South Korea in 2011. "Omic" technologies can be used to understand the mechanisms underlying chemical-induced diseases. Studies to determine the toxicity of chemicals may facilitate understanding of the mechanisms underlying the development of pulmonary fibrosis at a molecular level; thus, such studies may provide information about the toxic characteristics of various substances. In this review, we have outlined the cellular and molecular mechanisms underlying idiopathic pulmonary fibrosis and described pulmonary fibrosis induced by various chemicals, including bleomycin, paraquat, and PHMG-p, based on the results of studies performed to date.

Cigarette smoke is a major risk factor for several diseases, including chronic obstructive pulmonary and cardiovascular diseases. The toxicity of the cigarette smoke can be determined in vitro. The cytotoxicity test of the cigarette smoke is commonly conducted using the cigarette smoke condensate (CSC) and cigarette smoke extract (CSE). The CSC and CSE methods are well known for sampling of the particles and water-soluble compounds in the cigarette smoke, respectively. In this study, the CSC and CSE were analyzed by using a gas chromatography-mass spectrometry (GC-MS) system equipped with a wax column for separation of the volatile organic compounds. The cytotoxic effect of the CSC and CSE were evaluated thoroughly by comparing the analytical results of the CSC and CSE samples. The total concentration of the volatile organic compounds detected in the CSC sample was similar to that in the CSE sample based on the peak area. Except for the dimethyl sulfoxide solvent, nicotine had the highest concentration in the CSC sample, while acetonitrile had the highest concentration in the CSE sample. The compositions were as follows: (1) CSC sample: 55.8% nicotine, 18.0% nicotyrine, 3.20% 1,2,3-propanetriol, triacetate, 1.28% ethyl chloride, 1.22% phenol, etc. and (2) CSE sample: 18.7% acetonitrile, 18.0% acetone, 12.5% 2-hydroxy-2-methyl-propanenitrile, 8.98% nicotine, 5.86% nicotyrine, etc. In this manner, to accurately examine the cytotoxicity of the cigarette smoke using CSC or CSE, the components and their concentrations in the CSC and CSE samples should be considered.

Ginkgo biloba is a dioecious tree that has been used in traditional Chinese medicine for about 5,000 years. In previous studies on ginkgo biloba extract (EGb761) using in vitro systems, we confirmed that EGb761 has biphasic effects on estrogenicity. In this study, we evaluated the agonistic and antagonistic activities of EGb761 using a uterotrophic assay in immature female rats. To evaluate agonistic and antagonistic effects of EGb761 on uterus, 21-day-old immature Sprague-Dawley (SD) female rats were treated with EGb761 (100, 200, or 400 mg/kg) by oral gavage, 10 μg/kg of estradiol (E2) or 1 mg/kg tamoxifen (TM) by subcutaneous injection, or with EGb761 plus E2 or TM for 3 consecutive days. At the end of the treatment period, animals were sacrificed and their body weights and organ weights (liver, lung, spleen and kidney) were measured. In addition, estrogen-related gene expressions (IGFBP-1 in liver and CaBP-9 in uterus) were determined. During the experiment, no animal showed clinical signs, a change in body weight or died. EGb761 treatment alone had no effect on absolute/relative uterine weight, luminal epithelial cell height (LECH, μm), or luminal circumference (LC, μm). In addition, uterine weights, LECHs, and LC induced by E2 or TM were not significantly changed by EGb761 at any dose. These results collectively suggested EGb761 has no agonistic/antagonistic effects in utero.

Municipal sewage treatment plants (STPs) are thought to be important point sources of microplastics in freshwater systems and many peer-reviewed articles have been published on this issue since mid-2010s. In this review, we summarize existing literature on the occurrence of microplastics in STPs and experimental methods used for isolation and identification of microplastics. The number concentrations of microplastics in STP influents were 15.1-640 L-1 , whereas those in the STP effluents were highly variable and ranged from not detectable to 65 L-1 . For most of cases, conventional STPs are removing microplastics very effectively. Fragments and fibers are dominant shapes of microplastics. Thermoplastics (polyethylene and polypropylene) and polyester are the predominant materials recovered. Although further research is needed, size distribution of microplastics in STPs is likely to follow a power law, implying that different studies using different size cutoffs may be compared after establishing a power law relationship.

A method of rapidly decaying livestock carcasses is sought through Corine glutamicum, and furthermore, lysosomes are used to remove toxic microorganisms from livestock carcasses. The landfill was constructed on a laboratory scale. Optimized growth conditions of C. glutamicum that could quickly decay livestock carcasses were determined. Lysosomes were extracted from egg whites and used to treat contaminated soil to confirm their antimicrobial activities. Condition of C. glutamicum was activated, regardless both anaerobic and aerobic conditions, soil exists and, to be close to the optimum conditions as possible temperatures, moisture content was about 1/10 of the culture. Lysosomes were found to be effective in clearing soil contamination. C. glutamicum can accelerate the decay of livestock carcasses. A combination of C. glutamicum and lysomes could be used to treat soil contamination caused by decomposition of livestock.

Studies on the trend of air pollution in Tehran, Iran, as one of the most polluted metropolis in the world are scant, and today Tehran is known for its high levels of air pollutants. In this study, the trend of air pollution concentration was evaluated over the past 10 years (2004-2015). The data were collected from 22 stations of the Air Quality Control Company. Daily concentrations of CO, NO₂, SO₂, O₃, PM₁₀ were analyzed using SPSS 16 based on the statistical method, repeated measures, and intra-group test to determine the pattern of each pollutant changes. As a result of the 22 air pollution monitoring stations, NO₂ and SO₂ concentrations have been increasing over the period of 10 years. The highest anomaly is related to SO₂. The CO concentrations represent a descending pattern over the period, although there was a slight increase in 2013 and 2014. The O₃ concentrations declined in the following years. The average concentration of PM₁₀ has been rising during the period. Also we evaluated changes of each pollutant in different months and calculated the number of clean, healthy, unhealthy days for sensitive, unhealthy, very unhealthy, and dangerous groups. The study findings illustrated the necessity for larger investment in air pollution abatement. Overall, trends have been progressed to worsening, the number of healthy days has been declined and the number of unhealthy days has been increased in recent years.

There is limited literature on the frequency and distribution of pesticide exposures, specifically with respect to demographic and environmental factors in the United States. The purpose of this exploratory study was to investigate geographic trends and factors associated with unintentional pesticide exposures in children and adolescents in Texas. The study used an ecological design with secondary data. A spatial scan statistic, based on a Poisson regression model, was employed to identify spatial clusters of unintentional pesticide-related poison center exposures. Next, logistic regression models were constructed to identify potential demographic and environmental factors associated with unintentional pesticide-related poison center exposures. There were 59,477 unintentional pesticide-related poison center exposures from 2000 to 2013. The spatial scan statistic found a change in the number of counties in the identified clusters (e.g. , aggregation of counties with higher than expected exposures) for two time periods (2000-2006; 2007-2013). Based on the logistic regression models, factors associated with unintentional pesticide-related poison center exposures were percent black or African American population, year structure built, and percent moved in the past 12 months. In conclusion, this study found certain demographic and environmental factors may be associated with unintentional pesticide-related poison center exposures. Through understanding trends and associated factors, public health professionals can design interventions for populations at higher risk of pesticide exposures. This study also supports the use of spatial methods being utilized to expand upon current analysis of poison center data. Future research should confirm and build upon these findings.

The industrial complexes built during the course of economic development in South Korea played a pivotal role in the country's rapid economic growth. However, this growth was accompanied by health problems due to the pollutants released from the industrial complexes inevitably located near residential areas, given the limited land area available in South Korea. This study was conducted to evaluate the exposure to each pollutant emanating from industrial complexes for residents living in nearby areas, and to determine the substances requiring priority attention in future surveys. Pollutants were comprehensively categorized according to their emission and exposure levels based on data previously collected from the study areas. The emission, ambient concentration, and biomarker concentration levels of major pollutants emitted from eight national industrial complexes (Ulsan, Pohang, Gwangyang, Yeosu, Chungju, Daesan, Sihwa, and Banwol) were determined and tabulated. Each of the values was compared with the national/local average values, reference values, or control area concentrations depending on availability. Substances with completed exposure pathways and with high values for emissions, ambient concentrations, and biomarker concentrations were considered the substances posing exposure risks to the residents living near the corresponding industrial complex. The substances requiring continuous monitoring or supplementary exposure investigation were also categorized and presented. Lead and benzene had higher values for emissions, ambient concentrations, and biomarker concentrations in the Ulsan Industrial Complex area; thus, they were most likely to pose exposure risks to residents living in the area's neighborhoods. In other areas, styrene, xylene, cadmium, nitrogen oxide, trichloroethylene, nickel, manganese, and chromium required continuous monitoring, and arsenic, nickel, manganese, and chromium required biomarker measurements. In conclusion, the substances identified and categorized in this study need to be given appropriate attention in future surveys on exposure risks and health effects related to industrial complexes.