The Brownfields Redevelopment Program was started by the EPA in 1995 and seeks to use already contaminated sites rather than contaminate even more greenfields. Two of the biggest difficulties are making redevelopment profitable and protecting human health. Traditional human health risk assessment evaluates single chemical exposures and identifies the level below which no adverse effect will occur to the most sensitive subgroups of the population. For cancer–causing chemicals the risk must be lower than 1:1,000,000. When brownfield redevelopment sites are associated with high cost, extensive time and unmanageable uncertainty, additional greenfield sites will become contaminated and the contamination on current brownfield sites will remain un-remediated.
The citizens' advisory group addressing brownfields in a southern New York county has developed a risk matrix to evaluate the uncertainty of the available data, the toxicity of the known or suspected contaminants and the likely exposure routes for each brownfield site in the county. The matrix categorizes sites as high, medium or low risk according to exposure groups. The risk matrix complements the triad approach currently being developed by EPA to identify and manage project decision uncertainties, addresses uncertainty as well as toxicity and has the potential to reduce the cost of traditional health risk assessment at brownfield redevelopment sites. 相似文献
In this article, the authors propose a probabilistic alternative to the EPA's method that expresses the human population threshold as a probability distribution of values (rather than a single RfD value), taking into account the major sources of scientific uncertainty in such estimates. The approach is illustrated using much of the same data that USEPA uses to justify their current RfD procedure.
Like the EPA's approach, our approach recognizes the four key extrapolations that are necessary to define the human population threshold based on animal data: animal to human, human heterogeneity, LOAEL to NOAEL, and subchronic to chronic. Rather than using available data to define point estimates of “uncertainty factors” for these extrapolations, the proposed approach uses available data to define a probability distribution of adjustment factors. These initial characterizations of uncertainty can then be refined when more robust or specific data become available for a particular chemical or class of chemicals.
Quantitative characterization of uncertainty in noncancer risk assessment will be useful to risk managers who face complex trade-offs between control costs and protection of public health. The new approach can help decision-makers understand how much extra control cost must be expended to achieve a specified increase in confidence that the human population threshold is not being exceeded. 相似文献
The methodology of recording and systematization includes the following parameters: coal deposits; climate parameters; roads; rivers; land and surrounding objects; air polluters; water polluters; and soil polluters. Methods for calculating land deformation, air polluter emissions, and noise impact are also presented.
Based on the number and specificity of analyzed data, the paper provides a concept of the IS and an overview of environmental impact of underground coal mine technological units. The concept was used to present the results of a research conducted at the underground coal mine “Soko” in Serbia.
The results of this research can help many potential users realize their goals. Those goals are preventive by nature, since negative environmental impact can be predicted, which enables the environmental protection experts to take appropriate measures. 相似文献
A primary conclusion of the assessment for human and aquatic toxicity, across the entire life cycle of tin-lead solder, was the potential for impacts derived from the landfilling of lead. These results, based on broad assumptions about exposure, suggest that a more detailed risk assessment of the landfilling process would assist in better understanding the potential for health and environmental risks. We believe LCA data can be used to identify the need for focused risk assessments, allowing the two tools to effectively complement one another. Use of both methods could assist in understanding the effectiveness of the European ban on lead solder and its potential to improve public health. 相似文献
Objective: This study investigates the level of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the blood of the tea garden workers at risk of exposure to a mixture of pesticides.
Materials and methods: The study sample consisted of pesticide exposed workers, non-exposed (control), smokers and alcoholics. AChE and BuChE activity was measured and tested for significance.
Results: Results showed that AChE activity was half in the pesticide exposed individuals than controls (p≤ 0.001). BuChE activity was also significantly decreased in the pesticide exposed individuals than controls (p≤ 0.001), while AChE and BuChE activity in smokers and alcoholics were not different from that of controls. However, significantly decreased AChE and BuChE activities were recorded in pesticide exposed workers compared to smokers and alcoholics.
Conclusions: The results indicated that the decrease in enzyme activities in tea garden workers was due to mixed pesticides (containing organophosphates) exposure. Age was not found to influence the enzyme activities. However, the gender had little effect on the enzyme activities but the effect was not so prominent. 相似文献
Ecological Alternatives Assessment practices would place the highest priority on: (a) continued temporal and spatial evolution of existing complex ecological relationships, (b) acknowledgment of the inherent rights of all species, and (c) examination of alternatives to reduce effects of anthropogenic actions. These steps, as discussed, are not impossible to accomplish and are necessary for favorable short‐term (50–500 years) anthropocentric alternatives and maintenance of long‐term (+1,000 years) biodiversity of species and ecosystems. 相似文献
Lastly, the need for scientists to communicate with the public and the basis of effective presentation is discussed. 相似文献
The method considers the UK standard land uses (residential with and without plant uptake, allotment gardens, and commercial/industrial) by applying the default exposure factors and algorithms provided. Non-standard land uses can be also considered. Site-specific determinations of contaminant bioaccessibility or of plant-to-soil concentration factors may be used if available.
The method adopts the risk-based source-pathway-receptor pollutant linkage framework and a deterministic methodology. Exposure pathways considered are direct ingestion of soil and dust, consumption of home grown or allotment vegetables, ingestion of soil attached to such vegetables, inhalation of soil vapors outdoors and inhalation of soil vapors indoors. A test for the significance of the dermal pathway is also included.
It is not intended that the method be used to generate or replace UK Soil Guideline Values, because this can only be done by the appropriate authoritative bodies within the UK (Department of the Environment, Food and Rural Affairs and the Environment Agency). 相似文献
Objective: Ascertain the utility of measurements of single-strand breaks (SSB) in DNA for assessment of breast cancer risk.
Methods: Fine-needle aspirates of the breast, SSB by nick translation, percent breast density (PBD), Gail model risk, cumulative methylation index (CMI), enzymes of DNA repair and tissue antioxidants.
Results: DNA repair enzymes and 4-hydroxyestradiol were negatively associated with SSB; CMI and PBD were positively associated.
Conclusions: Quantitative measurement of SSBs by this procedure indicates the relative number of SSBs and is related to promoter methylation, antioxidant availability and percent breast density. 相似文献
PFBSK did not show acute and chronic aquatic, microorganisms and terrestrial animal toxicity, while exhibited some terrestrial plants toxicity. The ecotoxicology of PFBSK decreased sharply except for terrestrial plants compared with PFOS. Especially, for acute and chronic aquatic ecotoxicity, PFBSK is lower than 100 times those of PFOS.
Although the similar terrestrial plants toxicity level was observed for PFBSK and PFOS, the lower risk of PFBSK was deduced for the reason that there was far less chances to be exposed and retained in the soil and sediment for its high water solubility and low adsorption.
In conclusion, PFBSK showed lower ecotoxicity hazard and risk than those of PFOS. PFBSK could be an environmental friendly alternative to PFOS. 相似文献
In (half‐life carbaryl) = 24.3 ‐ 2.36(pH) ‐ 0.0788(t)
and In (half‐life malathion) = 5.98 + 2.84(pH) ‐ 0.326(pH 2) ‐ 0.202(t) + 0.00135(t 2)
where half‐life has units of hours, and temperature (t) has units °C. Both models accounted for a significant amount of total variation (P<0.0001) and had r2>0.97. Accuracy of these degradation models was evaluated by comparing predicted degradation of carbaryl and malathion to field and laboratory data. We suggest that use of these degradation models be restricted to conditions where water has 7 ≤. pH ≤. 10 for carbaryl, and 7 ≤ pH ≤ 8.2 for malathion. 相似文献
Methods: Lp-PLA2 activity was measured in 2538 CHD patients included in the Bezafibrate Infarction Prevention (BIP) study.
Results: Adjusting for patient characteristics and traditional risk factors, 1 standard deviation of Lp-PLA2 was associated with a hazard ratio (HR) of 1.12 (95% confidence interval (CI): 1.00–1.25) for mortality and 1.03 (0.93–1.14) for cardiovascular events. Lp-PLA2 did not significantly improve model discrimination, or calibration nor result in noteworthy reclassification.
Conclusions: Our results do not support added value of Lp-PLA2 for predicting cardiovascular events or mortality among CHD patients beyond traditional risk factor. 相似文献
Methods: Secretome and miRNAs were analyzed during the first two weeks and on clinical suspicion of ACR in the bile of 45 OLT recipients.
Results: Levels of CD44, CXCL9, miR-122, miR-133a, miR-148a and miR-194 were significantly higher in bile of patients who developed ACR within the first 6 months after OLT and during ACR.
Conclusion: Analysis of secretome and miRNA in bile could improve our understanding of the local inflammatory process during rejection. 相似文献
Methods: 94 outpatients with E HOA and NE HOA and 21 NC were enrolled. The radiological assessment of both hands was performed according to the Kellgren–Lawrence and Kallman score. Patients were divided into two subsets (lone HOA or generalized OA) based on clinically OA involvement of knee and hip. Serum visfatin, resistin and adiponectin levels were determined by ELISA assay.
Results: Visfatin was significantly higher in E HOA patients in comparison to NC and NE HOA group. Resistin showed a significant increase in both E HOA and NE HOA groups versus NC, in particular in generalized OA. No significant differences among groups were found in adiponectin. The Kallman score was more severe in the two subsets of E HOA patients compared to NE HOA.
Conclusions: This study showed increased levels of resistin in erosive and non-erosive HOA, and higher visfatin levels in E HOA in comparison to NE HOA. These data suggest the adipokines possible role in the pathogenesis of HOA and their potential usefulness as biomarkers of the disease. 相似文献
Aims: To examine whether antioxidant capacity and chemical composition of alpine plants change with increasing elevation.
Methods: We measured the Trolox-equivalent antioxidant capacity (TEAC) and chemical composition of five alpine plant species at 3016, 3814 and 4621 m a.s.l.
Results: With increasing elevation: (1) the TEAC increased and total phenols and tannins tended to increase in two forb and two shrub species but not in a sedge species; (2) concentrations of protein and fat increased in all five plant species; (3) polyunsaturated fatty acids (PUFA) increased and (4) mineral concentrations tended to decrease, but trends were inconsistent.
Conclusions: We conclude that with increasing elevation, TEAC and total phenols and tannins increased which we interpreted as an adaptation to higher oxidative stress; and protein and fat contents increased to support high metabolic activity. The increase in PUFA and the trend for minerals to decrease with increasing elevation require further investigation. 相似文献
Materials and methods: The association between serum YKL-40 and predefined outcome was evaluated in 1344 HF patients assigned to rosuvastatin or placebo.
Results: YKL-40 was not associated with outcome in adjusted analysis. In YKL-40 tertile 1, an effect on the primary outcome (HR 0.50, p?=?0.006) and CV death (HR 0.54, p?=?0.040) was seen by rosuvastatin in adjusted analysis.
Conclusions: A beneficial modification of outcome was observed with statin therapy in patients with low YKL-40 levels. 相似文献