Expression of 8-OHdG in Zosterisessor ophiocephalus from the Venetian lagoon,Italy

The aim of the present work was to evaluate the expression of 8-OHdG (8-hydroxy-2''-deoxyguanosine) in the benthic fish Zosterisessor ophiocephalus collected in two differently polluted sites of the Venetian lagoon (Porto Marghera and Caroman). We compared our data on 8-OHdG with those of CYP1A (Cytochrome P450, family 1, subfamily A, polypeptide 1), which is a well known biomarker for detoxification of contaminants. Immunohistochemistry with an antibody to 8-OHdG showed immunopositivity in nuclei of hepatocytes as well as in melanomacrophage centres of spleen and kidney, whereas an anti-CYP1A antibody exhibited positive immunostaining in the liver, kidney and ovary. The liver of males showed higher expression of both proteins than females. In animals from Porto Marghera site, the enzymatic assay for 8-OHdG exhibited higher levels in liver of males than in females. Western Blot analysis using the antibody anti-CYP1A recognized the presence of a band of about 60 kDa in the liver of males and females. Males exhibited a strong band, whereas in females the band showed a lower intensity. By using Real-Time PCR, the mRNA expression of CYP1A did not show any differences between males and females from each site, but it was at borderline significance level. Comparing the two sites, mRNA expression of CYP1A was significantly higher in the liver of both males and females from Porto Marghera than that of Caroman. The present data suggest that pollutants are bio-available as demonstrated by our biomarker analyses and may have a harmful effect on aquatic organisms such as Z. ophiocephalus. We report that the highest levels of hepatic 8-OHdG and CYP1A expression were detected in males, showing clear gender specificity.Key words: OHdG, CYP1A, fish, immunohistochemistry, molecular biology.     

Methodology for using contaminated soil leachability testing to determine soil cleanup levels at contaminated petroleum underground storage tank (UST) sites

The costs of environmental remediation at leaking petroleum underground storage tank (UST) sites are influenced significantly by soil cleanup levels. The use of conservative generic soil cleanup levels may be inappropriate at some sites contaminated by leaking petroleum USTs. At many contaminated sites, a primary objective of site remediation is long‐term protection of water resources (e.g., groundwater) from pollution. Leaching of pollutants from residual soil contamination to groundwater is a primary consideration in establishing site‐specific soil cleanup levels at fuel‐contaminated sites. The use of laboratory soil leachability testing methods may be useful in objectively evaluating the leaching potential of contaminants from residual soil contamination and estimating potential groundwater impacts. Developing soil cleanup levels that are protective of water resources must include a technically sound integration of site‐specific soil leachability data and contaminant attenuation factors. Evaluation of the leaching potentials of soil contaminants may also provide essential supplementary information for other site characterization methods that may be used to evaluate risks to human health. Contaminant leachability testing of soils may provide a cost‐effective and technically based method for determining soil cleanup levels that are protective of groundwater resources at contaminated petroleum UST sites.     

Life cycle assessment of soil and groundwater remediation technologies: literature review

Background, aim, and scope  

Life cycle assessment (LCA) is becoming an increasingly widespread tool in support systems for environmental decision-making regarding the cleanup of contaminated sites. In this study, the use of LCA to compare the environmental impacts of different remediation technologies was reviewed. Remediation of a contaminated site reduces a local environmental problem, but at the same time, the remediation activities may cause negative environmental impacts on the local, regional, and global scale. LCA can be used to evaluate the inherent trade-off and to compare remediation scenarios in terms of their associated environmental burden.     

Transport model parameter sensitivity for soil cleanup level determinations using sesoil and at123d in the context of the california leaking underground fuel tank field manual

The California Leaking Underground Fuel Tank Field Manual (LUFT Manual; WRCB, 1989) is used by the regulatory community, consultants, and industry in California to determine acceptable cleanup concentration goals for the remediation of hydrocarbon‐affected soils. The LUFT methodology is a semiquanitative approach that uses rating tables that consider the effects of local precipitation and the depth to ground water from the deepest affected soils, as well as anthropogenic and geologic factors. The latter factors are evaluated subjectively, with only the effects of local precipitation and depth to ground water accounted for quantitatively. To assess the effects of these variables on the hydrocarbon concentrations that could be left in soil while protecting ground water quality, the state of California performed modeling using SESOIL and AT123D. The results from a small number of simulations covering a very narrow range of input parameter values were then extrapolated to form the LUFT Manual rating tables, which cover ranges in precipitation and depth to ground water of 0 to 40 in. per year and 5 to 150 ft, respectively. Although the use of these tables generally results in conservative cleanup level determinations, the extrapolation method used and the lack of consideration for extremely sensitive input parameters (other than precipitation and depth to ground water) in the development of the tables calls into question their validity. A sensitivity analysis on the model input parameters is presented that highlights several critical input parameters that greatly affect cleanup concentration determinations. The sensitivity analysis shows that certain parameters that were fixed at conservative levels for the development of the LUFT Manual rating tables (e.g., biodegradation rate and soil organic carbon content) are more sensitive than precipitation and the depth to ground water. In many cases, site‐specific analysis will thus yield higher soil cleanup concentrations that are still protective of water quality. In addition, in some instances the cleanup concentrations in the LUFT Manual tables are not protective of water quality. To provide a firm basis for soil cleanup‐level determinations, site‐specific analysis is recommended whenever significant quantities of soil may require remediation. This will provide more cost‐effective remediation and greater assurance of water quality protection.     

In-Situ Remediation of TCE in Clayey Soils

The remediation of solvent contaminated low permeable soils poses a significant problem for many facilities. A consortium of industrial partners (Monsanto, DuPont and General Electric), the USEPA and the DOE jointly developed a technology that integrates electrokinetics with in-situ treatment of chlorinated organics to address this problem. The process, called Lasagna^TM, utilizes a DC electric field to move pore water and contaminants uniformly through the soil mass to treatment zones emplaced within the contaminated area. The emplacement is performed using common piling technologies and results in little or no wastes. The treatment materials emplaced are typically iron, coke and kaolin. After two in-field demonstrations, a full-scale Lasagna remediation system was implemented at the DOE facility in Paducah, KY for the remediation of TCE contaminated clay soils. The system was installed and operated over a two-year period. The process was shut down in December 2001 after meeting the cleanup target of 5.6 mg/kg specified by the Record of Decision (ROD) for the site. The final results show an average TCE concentration of 0.38 mg/kg.     

某焦化场地土壤中多环芳烃分布的三维空间插值研究

为准确界定污染场地土壤中多环芳烃在3维条件下的污染分布范围和受污染土方量,选择我国某焦化污染场地苯并(a)芘分布为研究对象,对比研究Krig-3D、IDW-Shepard、IDW-(Franke/Nielson)以及Nearest Neighbor 4种3维插值方法对界定污染范围的不确定性影响。结果表明,不同3维插值模型计算结果差异较大,交叉验证结果显示Krig-3D插值模型插值精度最高,插值结果能较真实地反映场地实际污染情况。通过修复目标对比确定进一步表明,基于4种插值模型计算所得的污染土壤土方量分别为8.51×105、5.62×105、7.12×105、1.09×106m3,选择合理的插值模型将对预测污染范围的不确定性产生重要影响。研究结果对分析污染范围和修复治理过程土方量确定提供重要参考。     

Impact of Risk-Based Corrective Action (RBCA) on State LUST Corrective Action Programs

Under sponsorship from the U.S. Environmental Protection Agency (USEPA) and the American Society of Testing & Materials (ASTM), a nationwide study evaluated the impact of risk-based corrective action (RBCA) on the performance of state environmental cleanup programs. The RBCA process for management of affected soil and groundwater sites was originally detailed in ASTM Standard E-1 739-95, Standard Guidelines for Risk-Based Corrective Action at Petroleum Release Sites, published in 1995 and reissued in expanded form in 1998. With strong support from the USEPA, the RBCA process has been adopted by many state agencies in the U.S in an effort to improve the management of environmental cleanup efforts, as needed to address increasing case backlogs and rising costs associated with remediation of leaking underground storage tank sites. To evaluate the success of these RBCA programs, the Risk-Based Decision-Making (RBDM) Performance Assessment Study, initiated in 1997, involved detailed evaluation of five state environmental agencies that had implemented regulatory programs closely modeled on the ASTM RBCA Standard. Comparison of pre-RBCA to post-RBCA program management statistics clearly demonstrates the positive impact of RBCA in terms of faster case processing rates, reduced environmental cleanup costs, and more effective targeting of resources toward higher-risk sites.     

Estimation of the migration potential of diesel fuel constituents from soil to ground water: A case study

A methodology for estimating the migration potential of diesel fuel constituents from soil to ground water was developed for a large commercial property impacted by diesel fuel. The diesel fuel impacts are associated with former railyard practices that occurred prior to 1970. The site is being redeveloped for commercial use. The proposed improvements for the site include an asphalt‐paved parking lot over the location of the diesel fuel‐impacted soils. The methodology is based on the composition of weathered diesel fuel and the migration characteristics and toxicity data of the diesel fuel constituents. Based on these considerations, the two elements of the methodology are (1) an evaluation of the migration potential of diesel fuel constituents in soil using the soil synthetic rainwater leachate laboratory analysis; and (2) a health‐risk assessment of the diesel fuel ground water impacts. This approach provided sufficient site‐specific data to support a regulatory agency decision allowing development to continue without active remediation of the site soils. If the methodology had not been applied to the site, a remedial method based on a 100 mg/kg to 1000 mg/kg TPH underground storage tank (UST) program soil cleanup level would have likely been required. Considering the project's time constraints and financial requirements, remedial options such as offsite disposal or onsite thermal treatment would have been used resulting in cleanup costs likely exceeding $500, 000. The potential value of this methodology can be best appreciated considering that, based on EPA estimates, there are approximately 295, 000 contaminated UST sites and a significant portion of these sites are contaminated with diesel fuel. These sites could benefit considerably from this approach.     

Assessment of environmental stress by the micronucleus and comet assays on Limnoperna fortunei exposed to Guaíba hydrographic region samples (Brazil) under laboratory conditions

The Guaíba Basin is a source of drinking water for Porto Alegre (RS, Brazil). The water from this basin receives industrial, urban, and rural waste from many sources. The mussel species Limnoperna fortunei was chosen based on population data, distribution, and sensitivity. Previous tests with comet assay and micronuclei frequency in this freshwater mussel have shown to be successful in biomonitoring studies. The aim of this study was to evaluate the genotoxic contamination of the Guaíba Lake Hydrographic Region, through the determination of damage by the micronuclei and comet assays in L. fortunei (golden mussel). Nine sampling sites were evaluated in three different seasons: five sites in the mouths of the main rivers that flow into Guaíba lake; one site at the mouth of a stream; one major site of sewage discharge; two sites at Guaíba lake, near a sewage discharge; and the control site in a preservation area. DNA damage was detected by the single cell gel assay, as well as the frequency of micronuclei in hemocytes of mussels exposed under laboratory conditions for 7 days to water and sediment samples. Significant results were found in different seasons in almost all sampling sites (P<0.05, ANOVA Dunnet's test). Most of the positive results were found in samples affected mainly by urban effluents. It was possible to observe that there was a weak relation between mutagenic and genotoxic responses and mussels inorganic elements contents. Seasonal variation was observed at different sampling sites, but always indicating a huge contamination near urban sewage discharge. These results are consistent with previous studies, allowing us to infer that urban contamination is the biggest problem in this region. It is also possible to infer that L. fortunei is a good sentinel organism for the Guaíba Basin.     

Heavy Metal Contamination in the Brownfield Soils of Cleveland

The results esults of a survey of heavy metal contamination at Cleveland area brownfields and public spaces are presented. Soils were analyzed using a 24?h, 1N HCl extraction procedure. The study was conducted to seek brownfield soils that manifest properties of “old” sequestered contamination and to develop a better understanding of the nature and extent of heavy metal burdens at brownfield sites in the Greater Cleveland area. The results indicated that Cleveland brownfields commonly yield soil burdens well above remediation triggers for residential soils and often yield values above industrial remediation triggers. It was also discovered that public areas in the vicinity of brownfields commonly have heavy metal contamination significantly above background levels and occasionally above residential remediation triggers. These results indicate that brownfields redevelopment initiatives should proceed with caution. The appropriate remediation goals or restrictions must be imposed to control urban exposure to heavy metal contamination.     

Cleanup standards for petroleum hydrocarbons. part 2. Case study comparisons of site‐specific cleanup standards with generic TPH standards

Many states across the U.S. use the total petroleum hydrocarbon (TPH) measurement as a regulatory tool for setting cleanup standards for underground storage tank sites and other petroleum‐related sites requiring cleanup. In Part 1 of this article (Michelsen and Petito Boyce, J. Soil Contam., 2(2): 109–124), alternative techniques and new methods for developing site‐specific cleanup standards for petroleum hydrocarbons were reviewed, including the use of chemical fingerprinting, constituent analysis, and human health and ecological risk assessment methods. In Part 2 of this article, the cost effectiveness and accuracy of these approaches are evaluated by comparing a generic TPH cleanup standards approach with site‐specific cleanup standards approaches for two actual sites in Washington State, a neighborhood gas station and a former bulk fuel storage facility. Based on these case studies, as well as consideration of other available approaches discussed in Part 1 of this article, recommendations are provided for selecting the most appropriate method of developing cleanup standards at a petroleum‐contaminated site.     

Cleanup standards for petroleum hydrocarbons. Part 1. Review of methods and recent developments

Many states across the U.S. use the total petroleum hydrocarbon (TPH) measurement as a regulatory tool for setting cleanup standards for underground storage tank sites and other petroleum‐related sites requiring cleanup. In Part I of this article, alternative techniques for developing site‐specific cleanup standards for petroleum hydrocarbons are reviewed, including the use of chemical fingerprinting, constituent analysis, and risk assessment methods that address hydrocarbons found in the environment. New developments in standard setting for petroleum hydrocarbons are described, including risk‐based standards for hydrocarbon mixtures and ecological risk‐based approaches. In Part 2 of this article, the cost‐effectiveness and accuracy of the most commonly used of these approaches will be evaluated by comparing a generic TPH cleanup standards approach with site‐specific cleanup standards approaches for two actual sites in Washington State, a neighborhood gas station and a former bulk fuel storage facility.     

Background levels of polycyclic aromatic hydrocarbons (PAH) and selected metals in new England urban soils

Polycyclic aromatic hydrocarbons (PAH) are byproducts of combustion and are ubiquitous in the urban environment They are also present in industrial chemical wastes, such as coal tar, petroleum refinery sludges, waste oils and fuels, and wood‐treating residues. Thus, PAHs are chemicals of concern at many waste sites. Risk assessment methods will yield risk‐based cleanup levels for PAHs that range from 0.1 to 0.7 mg/kg. Given their universal presence in the urban environment, it is important to compare risk‐based cleanup levels with typical urban background levels before utilizing unrealistically low cleanup targets. However, little data exist on PAH levels in urban, nonindustrial soils. In this study, 60 samples of surficial soils from urban locations in three New England cities were analyzed for PAH compounds. In addition, all samples were analyzed for total petroleum hydrocarbons (TPH) and seven metals. The upper 95% confidence interval on the mean was 3 mg/kg for benzo(a)pyrene toxic equivalents, 12 mg/kg for total potentially carcinogenic PAH, and 25 mg/kg for total PAH. The upper 95% confidence interval was 373 mg/kg for TPH, which exceeds the target level of 100 mg/kg used by many state regulatory agencies. Metal concentrations were similar to published background levels for all metals except lead. The upper 95% confidence interval for lead was 737 mg/kg in Boston, 463 mg/kg in Providence, and 378 mg/kg in Springfield.     

Survey of States' 2000 Soils Cleanup Standards for Petroleum Contamination

The establishment of cleanup standards for petroleum-contaminated soils (PCS) at the state level in the U.S. has had a fairly recent history beginning in the mid-1980s. Kostecki et al. (1988) surveyed the 50 states in 1985 and found of the 22 states that reported having established levels of cleanup for PCS, only five states considered the levels formal. The remaining 18 states considered the levels informal with 8 states considering establishing formal levels. Only 1 state had a formal numerical cleanup standard, and 3 had informal numerical standards. One state directly applied federal groundwater standards directly to soils. A follow-up survey in 1987 (Bell et al., 1989) indicated the rapid development of myriad different cleanup standards between and within states, including action levels, remediation goals, cleanup levels, etc. With the implementation of EPA's Office of Underground Storage Tanks final rules for regulating underground storage tanks in 1988 and the existing state of confusion regarding policies, rules and regulations for the cleanup of PCS at the state level, the Association for the Environmental Health of Soils (AEHS) began conducting state-by-state surveys of environmental regulatory agencies in 1990 to determine cleanup standards for PCS for use by the regulated community. The following tables represent AEHS' compilation of state data for PCS cleanup standards for 2000. The Survey was conducted by telephone interviews and submission of written information by the appropriate listed agencies. Many of the states' programs have changed to or are in the process of changing to Risk Based Corrective Action (RBCA) approaches. Thus, the format of the summaries are less standardized than past surveys in order to accurately reflect the states' program. Every attempt has been made to accurately represent states' cleanup standards, however, users should be cautioned to the limitations of compiling complex regulatory information into tabular form. The information should only be used as a reference guide and legal, economic or technical decisions should be based on specific information obtained directly from the appropriate agency in each state for each specific site.     

Evaluation of the total petroleum hydrocarbon (TPH) standard for JP‐4 jet fuel

The potential for use of alternatives to total petroleum hydrocarbons (TPH) for remediation purposes was examined specifically for JP‐4 fuel. The study objective was to determine the scientific basis for use of fuel constituents other than TPH in establishing soil cleanup standards at JP‐4‐contaminated sites. The general bases for TPH soil cleanup standards or goals were characterized. Problems with the use of TPH for cleanup included its lack of specificity (e.g., method‐, medium‐, and time‐from‐spill‐dependency) as well as the lack of toxicological relevance. JP‐4 fuel constituents (alkanes, BTEX [i.e., benzene, toluene, ethylbenzene, xylenes], polycyclic aromatic hydrocarbons [PAHs, i.e., chrysene], and naphthalenes) were identified as potential TPH alternatives. A series of criteria were applied to assess the viability of the use of specific JP‐4 constituents as TPH alternatives, and to select the most appropriate alternative. Criteria included chemical fate and transport, toxicity, and regulatory standards for relevant media of concern. Consideration of these criteria ultimately resulted in selection of benzene as the JP‐4 indicator of choice. The potential for altering risk‐based benzene soil cleanup concentrations (preliminary remediation goals, PRGs) was examined, and encompassed the basis for the existing benzene cancer slope factor (SF) as well as the role of distributional analysis of exposure parameters (Monte Carlo) that might be employed at JP‐4 spill sites. Results and conclusions are presented, and the implications for fuels other than JP‐4 are also discussed.     

污染土壤修复标准建立的方法体系研究

近年来,污染土壤修复技术发展很快,而污染土壤修复标准的建立则相对迟缓．在我国,直至目前甚至还没有开展相应的研究．为了推进我国该领域的工作,对污染土壤修复标准建立的方法体系进行了阐述,并提出了建立污染土壤修复标准应同时考虑技术清洁水平、环境背景水平和法规可调控清洁水平等3个基本变量．而从技术清洁水平这一变量来讲,应该包括2个方面的内涵,一是污染土壤修复技术本身所能达到的清洁目标,二是现有分析技术发展所能确认的污染物最低限量目标,即仪器可检出水平．     

Surrounding land use significantly influences adult mosquito abundance and species richness in urban mangroves

Mangroves harbor mosquitoes capable of transmitting human pathogens; consequently, urban mangrove management must strike a balance between conservation and minimizing public health risks. Land use may play a key role in shaping the mosquito community within urban mangroves through either species spillover or altering the abundance of mosquitoes associated with the mangrove. In this study, we explore the impact of land use within 500 m of urban mangroves on the abundance and diversity of adult mosquito populations. Carbon dioxide baited traps were used to sample host-seeking female mosquitoes around nine mangrove forest sites along the Parramatta River, Sydney, Australia. Specimens were identified to species and for each site, mosquito species abundance, species richness and diversity were calculated and were analyzed in linear mixed effects models. We found that the percentage of residential land and bushland in the surrounding area had a negative effect on mosquito abundance and species richness. Conversely, the amount of mangrove had a significant positive effect on mosquito abundance, and the amount of industrial land had a significant positive effect on species richness. These results demonstrate the need for site-specific investigations of mosquito communities associated with specific habitat types and the importance of considering surrounding land use in moderating local mosquito communities. A greater understanding of local land use and its influence on mosquito habitats could add substantially to the predictive power of disease risk models and assist local authorities develop policies for urban development and wetland rehabilitation.     

The development of chemical‐specific,risk‐based soil cleanup guidelines results in timely and cost‐effective remediation

Millions of dollars of limited state cleanup funds are spent each year in New Hampshire to identify, sample, excavate, and treat thousands of tons of contaminated soil. Cost analyses of numerous sites indicated that soil remediation costs alone reach upwards of $300,000.00 per site. The New Hampshire Department of Environmental Services “Interim Policy for Management of Soils Contaminated from Spills/Releases of Virgin Petroleum Products”; (DES, 1989, 1991) set conservative remediation goals based on total petroleum hydrocarbons in 1989 using the Leaching Potential Analysis method (California Luft Manual, 1989). A current review of available literature and several case histories indicated that chemical‐specific soil cleanup levels may be more appropriate for establishing remedial goals. New chemical‐specific soil cleanup guidelines using a risk‐based approach have been developed. These new guidelines are conservatively based using two principal considerations: (1) an assumed soil exposure scenario that estimated the human health risks associated with potential long‐term exposure to site soils via ingestion, inhalation and dermal contact and (2) the estimated fate and transport of chemicals of concern in the soil unsaturated zone. The first consideration assumed a total cancer risk that did not exceed 1 × 10^‐6. The second consideration employed the use of the SEasonal SOIL Compartment (SESOIL) model which simultaneously models water transport, sediment transport, and pollutant fate (US EPA, 1981). Several state soil standards from Oregon, Wisconsin, Massachusetts, and other states were extensively reviewed in order to develop a level of confidence that use of the SESOIL model was appropriate. A series of “sensitivity”; analyses was also performed in order to evaluate the response of the model to changes in various input parameters unique to New Hampshire's hydrogeologic conditions. Generic soil cleanup guidelines were developed for 24 petroleum‐based volatile and semivolatile chemicals of concern to be applied statewide. Site‐specific soil cleanup guidelines will be allowed if it can be demonstrated that insertion of site‐specific data into the model will not adversely affect groundwater quality. As a result of the above processes, timely and much more cost‐effective remediation will be achieved while still maintaining a high degree of protection of the groundwater quality and human health.     

Dimensions and approaches for Third World city water security

A rapid expansion of urban systems, particularly in less-developed countries, pose considerable challenges. Urbanization also provides opportunities for socio-economic progress. Relative contribution from the urban sector to national economic growth is very high. The fate and the role of the socio-economic system in local, regional and national development hinges on many circumstances. Apart from delicate social issues, deficiencies in water provision, internal distribution and a hazardous water and environmental quality represent basic and tangible daily problems. Urban water security requires fresh thinking at two levels. Some kind of basin authority (corresponding to a county council, i.e. a formal administrative and regulatory body for the geographical area within a river basin) in combination with a national water policy is required, notably in countries that contemplate, or are in the process of implementing, regional and sometimes inter-basin schemes to augment supply to growing conglomerations. Similarly, the generation of large volumes of waste water and the associated threat to downstream areas cannot be effectively tackled through conventional urban planning. Within the urban area, and particularly in non-regulated parts, there is an urgent need for institutional arrangements that facilitate operations for providers who have the capacity and ability to function under the prevailing circumstances. Introduction of effective production and treatment technologies are other necessary and urgent prerequisites to reach urban water security in Third World cities.