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1.
This paper summarizes the historical and recent research on the aquatic toxicology and bioconcentration potential of tetrabromobisphenol A (TBBPA), a major flame retardant in electronics. Historical studies on TBBPA are presented in detail, and are compared with more recent research. The historical studies have not been published to date, though they were pivotal in regulatory assessments by the European Union, Canada, and the USA. These assessments have enabled the use of TBBPA as a flame retardant in electronic applications, to the present. The studies were conducted under a Test Rule by the US Environmental Protection Agency in 1987, and were sponsored by member companies of the North American Flame Retardants Alliance (NAFRA) through the American Chemistry Council. The studies were conducted under Good Laboratory Practice procedures, and include 6 acute toxicity tests of TBBPA with fish, invertebrates, algae, and microbes, eight chronic tests, and three bioconcentration studies with fish and invertebrates. Methods and empirical data for each study are detailed in an electronic supplement. Results of the NAFRA studies are compared with recent findings on TBBPA toxicity. Molluscan shell growth may be uniquely sensitive to TBBPA, more sensitive than chronic fish or crustacean toxicity endpoints. Several of the NAFRA studies and several independent studies have reported toxicities exceeding the empirical water solubility limits of TBBPA (in the range of 2.0 mg/L depending on pH). The validity of these results is discussed.  相似文献   

2.
This paper considers several broad issues in the context of probabilistic assessment of the benefits of curtailing mercury (Hg) emissions from U.S. coal-fired power plants, based on information developed from recent literature and epidemiology studies of health effects of methylmercury. Exposure of the U.S. population is considered on the national scale, in large part because of recent questions arising from survey and experimental data about the relative importance of local deposition of airborne Hg. Although epidemiological studies have provided useful information, safe levels of Hg exposure remain uncertain, in part because of other dietary considerations in the populations that were studied. For example, much of the seafood consumed in one of the major studies was also contaminated with polychlorinated biphenyls, as are fish taken from some U.S. fresh waters. The primary epidemiological approach involves cross-study comparisons in relation to mean exposures, rather than detailed critiques of individual effects reported in each study. U.S. exposures are seen to be well below the levels at which adverse health effects are reported. This analysis supports the conclusion that unilateral reduction of Hg emissions from U.S. coal-fired power plants alone is unlikely to realize significant public health benefits.  相似文献   

3.
Environmental Science and Pollution Research - Numerous studies have linked outdoor levels of PM2.5, PM10, NO2, O3, SO2, and other air pollutants to significantly higher rates of Covid 19 morbidity...  相似文献   

4.
Investigations were undertaken to determine the adsorption-desorption, persistence and leaching of dithiopyr (S,S'-dimethyl 2-difluoromethyl-4-isobutyl-6-trifluoromethyl pyridine-3,5-dicarbothioate) in an alluvial soil under laboratory condition. The adsorption-desorption studies were carried out using batch equilibration technique. The mass balance studies showed that 83-97% of the pesticide was recovered during adsorption-desorption studies. The results revealed strong adsorption of dithiopyr in alluvial soil with Kd values ranging from 3.97-5.78 and Freundlich capacity factor (KF) value of 2.41. The strong adsorption was evident from the hysteresis effect observed during desorption. The hysteresis coefficients ranged from 0.17-0.40. The persistence studies were carried out at two concentrations (1.0 and 10.0 microg g(-1) level) under field capacity moisture and submerged condition by incubating the treated soil at 25 +/- 1 degrees C. In general, dithiopyr persisted beyond 90 days with half-life varying from 11.5-12.9 days under different conditions. The rate of application and moisture regimes had no overall effect on the persistence. The leaching studies carried out in packed column under saturated flow condition revealed that dithiopyr was highly immobile in alluvial soil. Only small amounts (0.02-0.04%) were recovered from leachate whereas major portion (99.9%) remained in top layer of the soil column. The data suggest that strong adsorption of dithiopyr will cause a greater persistence problem in the soil. However, the chances of its movement to ground water will be negligible due to its immobility.  相似文献   

5.
The carcinogenicity of 2,3,7,8-TCDD at multiple organ sites in animals has been well established by several cancer bioassays. Results of two of the most notable of these, the Kociba et al. (1978) rat feeding study and the National Toxicology Program (1980) gavage study in rats and mice showed hepatocellular carcinomas in two strains of female rats and male and female mice. Other tumor sites included carcinomas of the lung, tongue, hard palate and nasal turbinates, thyroid, and subcutaneous tissue. The evidence for carcinogenicity of 2,3,7,8-TCDD in animals is regarded as “sufficient” using the classification system of the International Agency for Research on Cancer (IARC).

Two Swedish epidemiologic case-control studies (Hardell and Sandstrom, 1979; Eriksson et al. 1979, 1981) reported a significant five- to sevenfold excess risk of soft-tissue sarcomas (STS) from occupational exposure to chlorinated phenoxyacetic acid herbicides and/or chlorophenols. Additionally, several small cohort studies collectively exhibited an unusual cluster of STS, significantly increased over combined expected incidence. Problems with these studies do not appear to be sufficient to discount this excess risk. The human evidence alone for the carcinogenicity of 2,3,7,8-TCDD is “inadequate” using the IARC classification. However, for 2,3,7,8-TCDD in combination with chlorinated phenoxyacetic acid herbicides and/or chlorophenols, the human evidence is considered to be “limited.” The overall evidence for carcinogenicity considering both animal and human studies would place 2,3,7,8-TCDD alone in the IARC category 2B, meaning that the substance is probably carcinogenic in humans. The overall weight of evidence for 2,3,7,8-TCDD in combination with chlorinated phenoxyacetic acid herbicides and/or chlorophenols is regarded as IARC category 2A, also meaning that they are probably carcinogenic for humans.

Using current EPA methodology for quantitatively estimating cancer risks, several animal data sets have been analyzed. Comparing the results, the upper-limit incremental unit risk estimate is 1.6 × 10−2 for a lifetime exposure of 1 ng/kg/day. This estimate is derived from a lifetime feeding study (Kociba et al., 1978) in which 2,3,7,8-TCDD induced tumors of the liver, lungs, hard palate, and nasal turbinates in female rats. Incremental unit cancer risks are also extrapolated for lifetime 2,3,7,8-TCDD exposures in water and air. Based on continuous lifetime exposure to 1 ng/L 2,3,7,8-TCDD in drinking water, the upper-limit estimate of extra cancer risk per individual is 4.5 × 10−3. For lifetime exposure to 1 pg 2,3,7,8-TCDD/m3 in the ambient air, the upper-limit individual risk is 3.3 × 10−5.  相似文献   


6.
Environmental Science and Pollution Research - Several studies have investigated the relationship between tourism, consumption of energy, globalization, and ecological footprint. However, the role...  相似文献   

7.
Curran SR  Agardy T 《Ambio》2002,31(4):303-305
Common property systems are a critical institution mediating the relationship between population change and environmental outcomes, especially in coastal and marine ecosystems. Evidence from El Salvador; Goa, India; and the Solomon Islands demonstrates how the social structures and institutions stemming from patterns of human migration variably influence environmental out-comes through their effects on common property resource institutions. In each of the case studies, the demographic phenomenon is not population growth or a change in numbers, but an underlying process that affects population size and growth rates: i.e. migration and associated social relations that result from or cause more migration. The following 3 cases studies provide the respective historical and cultural context to show that there is a nonlinear link between population and environment, which when explored reveals the importance of understanding how individuals and communities are embedded in sets of social relations that must be considered when evaluating environmental policies or when determining the causes of environmental degradation.  相似文献   

8.

Background and aim

Persistent organochlorine pollutants (POPs) have in epidemiological studies been associated with health hazards. The exposure window might be crucial and it is, accordingly, important to analyze exposure concentrations in samples collected at the window of interest. This makes the use of stored blood samples extremely interesting. However, small blood volumes from stored samples in biobanks means that the researchers in epidemiological studies most often have to select a limited number of biomarkers representing the POP exposure and abstain from analyses of lipid concentrations. This raises the question of the necessity of lipid adjustment. The aim of the present study was to evaluate the correlation between fresh weight and lipid adjusted concentrations.

Methods

We included data from studies were we have used the PCB congener 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB-153) as a biomarker for POP exposure and where fresh weight as well as lipid adjusted PCB-153 concentrations are known (n = 1628). The variety of the cohort members in the different studies gave us the possibility to better understand how well these measures correlate.

Results

When all individuals were included in the analyses a correlation coefficient of 0.95 between fresh weight and lipid adjusted serum concentrations was obtained. Restricting the analyses to specific subgroups (based on gender, fasting status, age and BMI) gave correlation coefficients between 0.85 and 0.97.

Conclusions

This study does strongly support the use of samples from biobanks in epidemiological studies for analyzing PCBs, at least regarding PCB-153, even though it is not possible to lipid adjust the results.  相似文献   

9.
Previous studies have found associations between traffic-related air pollution and asthma exacerbation in children, where exacerbations were measured according to emergency department visits and hospital admissions. Fewer studies have been undertaken that look at asthma exacerbations in a less severe primary care setting. Therefore, the authors sought to examine the associations between childhood asthma exacerbations, measured as acute visits to a primary care setting, and vehicular-traffic measures in a population of children aged 18 and under in the metropolitan Atlanta area. Statistical tests for differences of mean monthly visits for members with traffic measures above the median compared with below the median and for the upper quartile compared with the lower quartile were conducted. We also compared the odds of having one or more visits in a month for those who lived closer to a major roadway were compared with those who lived farther (greater than 300 m) from a major roadway. Poisson general linear modeling was used to determine associations between daily levels of acute visits for childhood asthma and traffic-related pollutants (zinc, EC [elemental carbon], and PM10 and PM2.5 [particulate matter with an aerodynamic diameter of ≤10 and ≤2.5 μm, respectively]) for different levels of traffic and distance measures. This analysis found that both larger traffic volumes and smaller distances to the nearest major roadway were positively and significantly associated with larger numbers of childhood asthma visits, when compared with less traffic and larger distances. Our findings point to motor vehicle traffic as an important contributor to childhood asthma exacerbations.
Implications: Previous studies have found associations between traffic-related air pollution and asthma exacerbation in children. However, these studies were mainly conducted in emergency department or hospital admission settings; little is known regarding less acute health effects. This analysis of the association between vehicular traffic measures and childhood asthma in a primary care setting suggests that motor vehicle traffic is a contributor to less acute asthma episodes in children. The present analysis of traffic-related air pollutants and childhood asthma were less conclusive, likely due to methods limitations outlined in the paper. The implication is that further evidence of adverse respiratory health effects in children due to motor vehicle traffic can be found in a primary care setting and similar studies should be considered.  相似文献   

10.
Environmental Science and Pollution Research - Few studies have documented the air quality, noise, thermal comfort, and health risk assessment of household kitchens related to Sub-Sahara Africa. In...  相似文献   

11.
Investigations were undertaken to determine the adsorption–desorption, persistence and leaching of dithiopyr (S,S′-dimethyl 2-difluoromethyl-4-isobutyl-6-trifluoromethyl pyridine-3,5-dicarbothioate) in an alluvial soil under laboratory condition. The adsorption–desorption studies were carried out using batch equilibration technique. The mass balance studies showed that 83–97% of the pesticide was recovered during adsorption–desorption studies. The results revealed strong adsorption of dithiopyr in alluvial soil with Kd values ranging from 3.97–5.78 and Freundlich capacity factor (KF) value of 2.41. The strong adsorption was evident from the hysteresis effect observed during desorption. The hysteresis coefficients ranged from 0.17–0.40.

The persistence studies were carried out at two concentrations (1.0 and 10.0 μg g?1 level) under field capacity moisture and submerged condition by incubating the treated soil at 25±1°C. In general, dithiopyr persisted beyond 90 days with half-life varying from 11.5–12.9 days under different conditions. The rate of application and moisture regimes had no overall effect on the persistence. The leaching studies carried out in packed column under saturated flow condition revealed that dithiopyr was highly immobile in alluvial soil. Only small amounts (0.02–0.04%) were recovered from leachate whereas major portion (99.9%) remained in top layer of the soil column. The data suggest that strong adsorption of dithiopyr will cause a greater persistence problem in the soil. However, the chances of its movement to ground water will be negligible due to its immobility.  相似文献   

12.
Although a number of comprehensive reviews have examined global ecosystem services (ES), few have focused on studies that assess urban ecosystem services (UES). Given that more than half of the world’s population lives in cities, understanding the dualism of the provision of and need for UES is of critical importance. Which UES are the focus of research, and what types of urban land use are examined? Are models or decision support systems used to assess the provision of UES? Are trade-offs considered? Do studies of UES engage stakeholders? To address these questions, we analyzed 217 papers derived from an ISI Web of Knowledge search using a set of standardized criteria. The results indicate that most UES studies have been undertaken in Europe, North America, and China, at city scale. Assessment methods involve bio-physical models, Geographical Information Systems, and valuation, but few study findings have been implemented as land use policy.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0504-0) contains supplementary material, which is available to authorized users.  相似文献   

13.
During the spring and summer of 2000, 2001, and 2002, gaseous and particulate matter (PM) fuel-based emission factors for approximately 150,000 low-tailpipe, individual vehicles in the Las Vegas, NV, area were measured via on-road remote sensing. For the gaseous pollutants (carbon monoxide, hydrocarbons, and nitrogen oxide), a commercial vehicle emissions remote sensing system (VERSS) was used. The PM emissions were determined using a Lidar-based VERSS. Emission distributions and their shapes were analyzed and compared with previous studies. The large skewness of the distributions is evident for both gaseous pollutants and PM and has important implications for emission reduction policies, because the majority of emissions are attributed to a small fraction of vehicles. Results of this Las Vegas study and studies at other geographical locations were compared. The gaseous pollutants were found to be close to those measured by VERSS in other U.S. cities. The PM emission factors for spark ignition and diesel vehicles are in the range of previous tunnel and dynamometer studies.  相似文献   

14.
15.
Environmental Science and Pollution Research - Plastic pollution is a major environmental issue that affects coasts all around the world. Many studies point out the importance of a better...  相似文献   

16.
Abstract

During the spring and summer of 2000, 2001, and 2002, gaseous and particulate matter (PM) fuel-based emission factors for ~150,000 low-tailpipe, individual vehicles in the Las Vegas, NV, area were measured via on-road remote sensing. For the gaseous pollutants (carbon monoxide, hydrocarbons, and nitrogen oxide), a commercial vehicle emissions remote sensing system (VERSS) was used. The PM emissions were determined using a Lidar-based VERSS. Emission distributions and their shapes were analyzed and compared with previous studies. The large skewness of the distributions is evident for both gaseous pollutants and PM and has important implications for emission reduction policies, because the majority of emissions are attributed to a small fraction of vehicles. Results of this Las Vegas study and studies at other geographical locations were compared. The gaseous pollutants were found to be close to those measured by VERSS in other U.S. cities. The PM emission factors for spark ignition and diesel vehicles are in the range of previous tunnel and dynamometer studies.  相似文献   

17.
Environmental Science and Pollution Research - Advanced oxidation processes (AOPs) are efficient methods for water purification. However, there are few studies on using peroxymonosulfate (PMS) to...  相似文献   

18.
A field study on the photolysis of perfluoroalkyl substances (PFASs) was conducted at high altitudes in Mt. Mauna Kea (Hawaii, USA; 4200 m) and Mt. Tateyama (Toyama, Japan; 2500 m). Results of photolysis of PFASs in the field were further confirmed in laboratory studies. Perfluorooctanesulfonate (PFOS), which is perceived as a non-degradable chemical in the environment, can undergo photolysis. Long chain PFASs can be successively dealkylated to short chain compounds such as perfluorobutyric acid (PFBA) and perfluorobutane sulfonate (PFBS), but the short chain compounds were relatively more resistant to photodegradation. These results suggest that environmental levels of short chain PFASs would increase both due to their formation from photolysis of long chain PFASs and from direct releases. Earlier studies on photolysis of PFASs were focused on the formation of perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs) from precursor compounds (such as fluorotelomer alcohols) under laboratory conditions. Our study suggests that PFSAs and PFCAs themselves can undergo photodegradation in the environment.  相似文献   

19.
Environmental Science and Pollution Research - The inhibitory effect of plants on algae offers a new and promising alternative method for controlling harmful algal blooms. Previous studies showed...  相似文献   

20.
Gene E. Likens 《Ambio》2021,50(2):278
Early studies published in Ambio showed large-scale acidification of lakes in southern Sweden and Norway from acid rain. These studies were important for delimiting various scientific issues and thus for eventually contributing to legislation, which reduced emissions of sulfur dioxide and nitrogen oxides and helped to mitigate this major environmental problem. Long-term studies and monitoring in Sweden and Norway and at Hubbard Brook Experimental Forest in New Hampshire helped guide this legislation in Europe and in the USA.  相似文献   

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