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1.
Plants were examined at three different locations in the eastern part of the United States to determine whether damage from air pollution had occurred. This paper discusses sulfur dioxide damage in the metropolitan New York City area; hydrogen fluoride damage near a glass fiber manufacturing plant in the midwest; and hydrochloric acid mist and chlorine damage from a manufacturing operation in an eastern state. The symptoms that developed in vegetation were often found to be similar. Chemical and microscopical analyses were helpful in diagnosing the toxicants.  相似文献   

2.
Abstract

The aim of this study was to evaluate the DNA damage in soybean growers during two agricultural periods of a crop season (high and low exposure) and a control group, as well as butyrylcholinesterase (BChE) activity during these exposure periods in order to estimate the degree of BChE inhibition for the exposed group. DNA damage in peripheral whole blood was evaluated by the comet assay and plasma BChE activity was accessed as a measure of exposure to cholinesterase inhibitors. None of the soybean growers reported using full Personal Protective Equipment (PPE). BChE was lower in high exposure period than in low exposure period and DNA damage index was significantly increased in the high exposure period than in the low exposure period. In addition, DNA damage in both exposure periods was higher than control group. No correlation was found between exposure time and DNA damage and BChE activity. However, negative correlation was observed between DNA damage in high and low exposure periods. The results indicate that soybean growers are exposed to cholinesterase inhibitors and to pesticides mixtures with genotoxic potential.  相似文献   

3.
Ecological sampling can be labor intensive, and logistically impractical in certain environments. We optimize line intercept sampling and compare estimation methods for assessing feral swine damage within fragile wetland ecosystems in Florida. Sensitive wetland sites, and the swine damage within them, were mapped using GPS technology. Evenly spaced parallel transect lines were simulated across a digital map of each site. The length of each transect and total swine damage under each transect were measured and percent swine damage within each site was estimated by two methods. The total length method (TLM) combined all transects as a single long transect, dividing the sum of all damage lengths across all transects by the combined length of all transect lines. The equal weight method (EWM) calculated the damage proportion for each transect line and averaged these proportions across all transects. Estimation was evaluated using transect spacings of 1, 3, 5, 10, 15, and 20 m. Based on relative root mean squared error and relative bias measures, the TLM produced higher quality estimates than EWM at all transect spacings. Estimation quality decreased as transect spacing increased, especially for TLM. Estimation quality also increased as the true proportion of swine damage increased. Diminishing improvements in estimation quality as transect spacings decreased suggested 5 m as an optimal tradeoff between estimation quality and labor. An inter-transect spacing of 5 m with TLM estimation appeared an optimal starting point when designing a plan for estimating swine damage, with practical, logistical, economic considerations determining final design details.  相似文献   

4.
The objective of the study was to evaluate the potential risk of DNA damage due to exposure to a mixture of the most widely used pesticides, namely endosulfan, chlorpyriphos and thiram at an environmentally relevant concentration (5 μM each) and the DNA protective capacity of sulforaphane (SFN) (10–30 μg/mL). DNA damage in human lymphocytes was ascertained with Single Cell Gel Electrophoresis (SCGE), also called Comet Assay. For positive control, H2O2 at 100 mM was used. The pesticide mixture produced DNA damage at the concentration used in the lymphocytes. SFN was able to offer a statistically significant (P < 0.01), concentration-dependant protection to DNA damage between 10–20 μg/mL in both the pre-incubation and co-incubation strategies. The results indicate that exposure to low levels of these pesticide mixtures can induce DNA damage, and the presence of SFN in diet may reduce the incidence of genetic damage, especially in farm workers. However, it is not clear whether SFN is involved in quenching of the free radicals generated by the pesticide mixture or it is involved in DNA repair mechanism.  相似文献   

5.
Wang G  Deng S  Li C  Liu Y  Chen L  Hu C 《Chemosphere》2012,88(4):413-417
Radiation with UV-B increased the damage to DNA in Scytonema javanicum, a desert-dwelling soil microorganism, and the level of damage varied with the intensity of UV-B radiation and duration of exposure. Production of reactive oxygen species (ROS) also increased because of the radiation. Different exogenous chemicals (ascorbate acid, ASC; N-acetylcysteine, NAC; glyphosate, GPS; and 2-methyl-4-chlorophenoxyacetic acid, MCPA-Na) differed in their effect on the extent of DNA damage and ROS production: whereas NAC and ASC protected the DNA from damage and resulted in reduced ROS production, the herbicides (GPS and MCPA-Na) increased the extent of damage, lowered the rate of photosynthesis, and differed in their effect on ROS production. The chemicals probably have different mechanisms to exercise their effects: NAC and ASC probably function as antioxidant agents or as precursors of other antioxidant molecules that protect the DNA and photosynthetic apparatus directly from the ROS produced as a result of UV-B radiation, and GPS and MCPA-Na probably disrupt the normal metabolism in S. javanicum to induce the leaking of ROS into the photosynthetic electron transfer pathway following UV-B radiation, and thereby damage the DNA. Such mechanisms have serious implications for the use of environment-friendly herbicides, which, because they can destroy DNA, may prove harmful to soil microorganisms.  相似文献   

6.
近年来,随着我国经济的发展,次级河流突发性水污染事件频繁发生,对生态环境及居民生活造成了严重的影响。次级河流突发性水污染事件发生后,为减少污染造成的损失和影响,保证受损的环境资源得到恢复和补偿,不仅要立即采取行之有效的应急处置措施,而且应当积极开展环境损害鉴定评估工作,全面追究污染者的环境责任。根据次级河流本身的特点,结合各省市在环境应急处置过程中的具体做法,建立了一套应对突发性次级河流水污染事件的应急处置工作程序;阐述了环境损害鉴定评估的必要性、工作方法和技术路线,同时从受损环境资源的确认、污染源和污染物的识别以及暴露途径的建立3个方面构建了开展次级河流突发性水污染事件环境损害鉴定评估工作的因果关系链条,对实际开展相关工作具有重要意义。  相似文献   

7.

DNA damage may develop at any dose of ionizing radiation. DNA damage activates pathways that regulate cell growth and division or coordinate its replication and repair. The repair pathways, base excision repair (BER) and single-strand break repair (SSBR), can repair such damages efficiently and maintain genome integrity. Loss of this repair process or alteration of its control will be associated with serious outcomes for cells and individuals. This study aimed to determine the relationship between XRCC1 (Arg194Trp, Arg280His, and Arg399Gln), OGG1 (Ser326Cys), and XRCC3 (Thr241Met) SNPs and DNA damage and to identify high-risk individuals with reduced DNA repair capacity. This case-control study was conducted on 80 subjects; 50 subjects working in Clinical Oncology and Nuclear Medicine Department in Assiut University Hospital along with 30 controls. A total of 1 mL blood samples were collected for Single-Cell Gel Electrophoresis Technique (Comet Assay) for detection of DNA damage in those subjects. A total of 3 mL fresh blood samples were collected and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)–based technique. DNA damage detected by comet test was significantly high in IR-exposed workers than control. Statistically high significant difference was found in exposed subjects versus control subjects regarding the frequencies of the variant alleles of hOGG1326, XRCC1280 & 399, and XRCC3241. The level of DNA damage was not affected by OGG1326 SNPs when comparing subjects of wild genotype with those of (pooled) variants either in the exposed staff or in the control group while XRCC1280, 399 and XRCC3241 variant alleles had an influence on the studied DNA damage biomarker. Moreover, genotyping distribution pattern was highly variable in relation to gender. The present study indicated a relationship between DNA damage detected by comet test and single nucleotide polymorphisms in genes coding for DNA certain repair enzymes. Individuals occupationally exposed to low doses of ionizing radiation could be at great risk and more susceptible to the increased DNA damage if they have inherited genetic polymorphism.

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8.
Gu MB  Min J  Kim EJ 《Chemosphere》2002,46(2):289-294
A recombinant bioluminescent Escherichia coli, DPD2794, containing the recA promoter region fused to luxCDABE originating from Vibrio fischeri was used for detecting genotoxicity caused by endocrine disrupting chemicals (EDCs) to cells. As well, several other recombinant bioluminescent bacteria, including TV1061, which is sensitive to protein damage (grpE::luxCDA BE), DPD2511, sensitive to oxidative damage (katG::luxCDABE), and DPD2540, sensitive to membrane damage (fabA::luxCDABE), were used for evaluating other possible modes of toxicity. It was found that the recombinant bacteria could monitor the toxic effect, not estrogenic effect, due to the presence of various EDCs through the measurement of bioluminescence (BL) and cell growth rate, which depend upon the type of toxicity occurring and which of the four strains was used. In addition, it was found that the damage caused by EDCs can be classified into several groups upon their mechanisms of toxic action.  相似文献   

9.
In 71 adults residing in Florence, Italy, enrolled in a prospective study, we investigated the correlation between individual levels of oxidative DNA damage detected by the Comet assay in circulating lymphocytes, and a specific ozone exposure score calculated in 10 different time-windows (0-5 to 0-90 days) before blood drawing, based on daily measurements provided by the local environmental monitoring system.Overall, statistically significant positive correlations between average ozone concentrations and DNA damage emerged in almost all time-windows considered; correlations were more evident among males, non-smokers, and traffic-exposed workers. Multivariate regression analyses taking into account selected individual characteristics, showed an independent effect on DNA damage of average ozone concentrations in the last 60-90 days before blood drawing. Local residents showed a divergent pattern with correlations restricted to shorter time-windows.Our results suggest that ozone concentrations at ground levels modulate oxidative DNA damage in circulating lymphocytes of residents of polluted areas.  相似文献   

10.
A grading system was developed to rate the moisture damage profile of dwellings and to study the relationship between moisture-induced indoor air problems and occupant health. A total of 630 randomly selected houses and apartments, built between 1950 and 1989, were visually inspected. Moisture observations were standardized into three damage levels. Thus, a system to classify the homes into three grades was devised. The two grades of homes associated with the highest levels of damage were graded as index homes. Overall, 51% of the sample had some kind of moisture fault in them and one in every three homes (33%) was classified as an index home. The mean number of damage incidents in the index dwellings varied from 1.4 to 2.6. The mean number of damage incidents in the reference homes was 0.28. Prevalence of index dwellings was significantly higher (p < 0.01) in houses (38%) than in apartments (26%). There was no major difference in the prevalence of index buildings in houses built in any particular decade (30-35%). Moisture was observed in 28% of bathrooms, in 10% of kitchens, and in 17% of other spaces. Indoor relative humidity (RH) levels were low in most homes.  相似文献   

11.
The lungs of exposed mice taken during 2- to 3-hour heavy smog periods (over 0.4 ppm total oxidants) showed various degrees of cytoplasmic damage in the alveolar epithelial cells. The extent of damage was markedly age-dependent. Alveolar wall cells taken during heavy smog from 5-month-old animals contained slightly more lamellar inclusion bodies than corresponding animals kept in clean air. The cytoplasm of alveolar cells of 9-month-old animals sacrificed during heavy smog was severely disorganized; however, animals of this age showed a marked recovery 14 hours following the smog peak. In a group of older mice (21 months), similar cytoplasmic damage was obvious, and those sacrificed 24 hours after the heavy smog peak showed even more cellular disruption, suggesting irreversible damage in the older animals. The effect of synthetic photochemical smog showed a pattern of ultrastructural alterations similar to that of the heavy natural smog. Some permanent changes occurred in alveolar cells of 15-month-old mice. Partial recovery of lining cells took place, but few wall cells and phagocytes remained. If older lung tissue has relatively fewer wall cells as is indicated, recovery is decreased to the point of permanent damage. Coupled with extensive disruption of lining membranes, exposures of this nature may well cause the death of older animals.  相似文献   

12.
Picloram (4-amino-3,5,6-trichloropicolinic acid) is a liquid auxinic herbicide used to control broad-leaved weeds. Picloram is representing a possible hazard to ecosystems and human health. Therefore, in this study, DNA methylation changes and DNA damage levels in Phaseolus vulgaris exposed to picloram, as well as whether humic acid (HA) has preventive effects on these changes were investigated. Random amplified polymorphic DNA (RAPD) techniques were used for identification of DNA damage and coupled restriction enzyme digestion-random amplification (CRED-RA) techniques were used to detect the changed pattern of DNA methylation. According to the obtained results, picloram (5, 10, 20, and 40 mg/l) caused DNA damage profile changes (RAPDs) increasing, DNA hypomethylation and genomic template stability (GTS) decreasing. On the other hand, different concentrations of applied HA (2, 4, 6, 8, and 10%) reduced hazardous effects of picloram. The results of the experiment have explicitly indicated that HAs could be an alternative for reducing genetic damage in plants. In addition to the alleviate effects of humic acid on genetic damage, its epigenetic effect is hypomethylation.  相似文献   

13.
ABSTRACT

A grading system was developed to rate the moisture damage profile of dwellings and to study the relationship between moisture-induced indoor air problems and occupant health. A total of 630 randomly selected houses and apartments, built between 1950 and 1989, were visually inspected. Moisture observations were standardized into three damage levels. Thus, a system to classify the homes into three grades was devised. The two grades of homes associated with the highest levels of damage were graded as index homes.

Overall, 51% of the sample had some kind of moisture fault in them and one in every three homes (33%) was classified as an index home. The mean number of damage incidents in the index dwellings varied from 1.4 to 2.6. The mean number of damage incidents in the reference homes was 0.28. Prevalence of index dwellings was significantly higher (p < 0.01) in houses (38%) than in apartments (26%). There was no major difference in the prevalence of index buildings in houses built in any particular decade (30-35%). Moisture was observed in 28% of bathrooms, in 10% of kitchens, and in 17% of other spaces. Indoor relative humidity (RH) levels were low in most homes.  相似文献   

14.
Nitrogen dioxide in air induced lipid oxidation and oxidative damage of human erythrocyte membrane. Increased fluorescence formation and protein cross-linking of erythrocyte ghosts were observed when they were exposed to nitrogen dioxide in air. The membrane damage was extensively potentiated by a small amount of oxy- and methemoglobin but little by a large amount of hemoglobin.  相似文献   

15.
Fish gill importance in toxicants uptake, bioconcentration and excretion allied to meagre knowledge on branchial damage/protection responses substantiate this study. Five critical sites in Ria de Aveiro (Portugal) were assessed in comparison with a reference site (Torreira), focusing on Liza aurata gill antioxidant defences versus damage (oxidative and genetic). Only in Barra fish displayed damage (lipid peroxidation) though no differences were found in antioxidants. In all other sites, except Rio, antioxidant alterations were found. Thus, fish from Gafanha, Laranjo and Vagos showed higher total glutathione, glutathione peroxidase and catalase. Higher glutathione reductase and glutathione S-transferase activity was also found in the first and the last sites, respectively. In Laranjo, metallothionein levels were higher though lower in Gafanha and Vagos. In general, damage was not accompanied by defences weakening confirming that predicting damage based on antioxidants depletion is not straightforward. The integrated biomarker response index ranked sites as: Gafanha > Barra > Laranjo > Vagos > Rio > Torreira.  相似文献   

16.
As a result of air pollutant emissions from the industrial complex of Cubat?o, Brazil, the Atlantic Forest vegetation of the Serra do Mar shows severe and widespread damage. In order to obtain information on the type, intensity and causes of the vegetation damage, bioindicator plants were exposed at different distances from the emission sources. Air-pollution-induced effects were evaluated by estimation of visible injury symptoms and chemical analyses of leaves. The results prove the occurrence of phytotoxic levels of photochemical oxidants in wide parts of the research area. Intense fluoride-induced damage and high leaf fluoride concentrations were found in a valley downwind of fertiliser industries. The study showed that some of the traditional standardised bioindication methods from temperate climates may be successfully employed in biomonitoring programmes in tropical and subtropical regions.  相似文献   

17.
The effects of elevated concentrations of atmospheric tropospheric ozone (O3) on DNA damage in five trembling aspen (Populus tremuloides Michx.) clones growing in a free-air enrichment experiment in the presence and absence of elevated concentrations of carbon dioxide (CO2) were examined. Growing season mean hourly O3 concentrations were 36.3 and 47.3 ppb for ambient and elevated O3 plots, respectively. The 4th highest daily maximum 8-h ambient and elevated O3 concentrations were 79 and 89 ppb, respectively. Elevated CO2 averaged 524 ppm (+150 ppm) over the growing season. Exposure to O3 and CO2 in combination with O3 increased DNA damage levels above background as measured by the comet assay. Ozone-tolerant clones 271 and 8L showed the highest levels of DNA damage under elevated O3 compared with ambient air; whereas less tolerant clone 216 and sensitive clones 42E and 259 had comparably lower levels of DNA damage with no significant differences between elevated O3 and ambient air. Clone 8L was demonstrated to have the highest level of excision DNA repair. In addition, clone 271 had the highest level of oxidative damage as measured by lipid peroxidation. The results suggest that variation in cellular responses to DNA damage between aspen clones may contribute to O3 tolerance or sensitivity.  相似文献   

18.

The present study assessed the DNA damage in environmentally exposed volunteers living in seven municipalities in an industrial coal region, through the use of the comet assay with blood cells and the micronucleus test with buccal cells. Blood and buccal smears were collected from 320 male volunteers living in seven cities inserted in a coal region. They were ages of 18 and 50 years and also completed a questionnaire intended to identify factors associated with DNA damage through a Poisson regression analysis. The comet assay detected significant differences in DNA damage in volunteers from different municipalities, and neighboring cities (Pedras Altas, Aceguá, and Hulha Negra) had a higher level of DNA damage in relation to control city. Some of the risk factors associated with identified DNA lesions included residence time and life habits. On the other hand, the micronucleus test did not identify differences between the cities studied, but the regression analysis identified risk factors such as age and life habits (consumption of mate tea and low carbohydrates diet). We conclude that there are differences in the DNA damage of volunteers from different cities of the carboniferous region, but the presence of micronuclei in the oral mucosa does not differ between the same cities. Furthermore, we alert that some related factors may increase the risk of genotoxicity, such as residence location and time, and living and food habits. Finally, we suggest the need for continuous biomonitoring of the population, as well as for investing in health promotion in these vulnerable populations.

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19.
慧星试验对水体安全性分析研究   总被引:1,自引:0,他引:1  
利用彗星试验检测苏南某湖泊湖心区、长江某取水口及其给水处理厂出水水样的遗传毒性,并对结果进行分析研究.结果表明,各水样均能引起DNA损伤,在丰水期致DNA损伤作用的大小顺序为给水厂出水水样>湖泊水样>长江取水口水样;在枯水期致DNA损伤作用的大小顺序为湖泊水样>长江取水口水样>给水厂出水水样.随着染毒剂量的加大,细胞损伤率增加,细胞受损的程度也在加重,并向3、4级损伤集中,呈明显的剂量-效应关系.  相似文献   

20.
Whereas most estimates of material damage are based on industrial surveys, the estimates produced in this study were derived from material damage experiments and ambient air quality data. Air quality data on SO2 were obtained from 200 or more monitoring sites primarily located in heavily populated or polluted areas. Material threshold damage function data were then compared with SO2 levels, and an estimate of losses, as reflected in increased maintenance and replacement costs, was determined. Estimates of the total stock of various materials in use were derived from census and industry data and allocated geographically according to population. A substantial decrease in the ambient SO2 levels, particularly in larger urban areas, has occurred during the past five years. From 1968 to 1972, the estimated amount of material damage from SO2 in the U. S. decreased from $900 million/yr to less than $100 million. During this period, the estimated percentage of man made materials exposed to SO2 levels exceeding the proposed secondary annual average standard (60 μg/m3) and primary annual average standard (80 μg/m3) in the U. S. fell respectively, from 20% to less than 5% and from more than 10% to less than 1%. Most of the present loss is attributed to corrosion damage of metallic surfaces that are normally exposed to the ambient environment.  相似文献   

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