Field screening methods for the analysis of explosives (for which commercial test kits are generally available) are reviewed. These techniques include immunoassays, photometric methods, bio and chemical sensors as well as thin layer chromatography. Basic aspects of these techniques are discussed, their validation is presented and their application to water and soil samples from hazardous ammunition waste is described. An evaluation of field studies with commercial test kits demonstrates that these techniques can be applied successfully for both the exploration of suspected contaminated sites and their sanitation. These methods are used on-site. In general, they allow short analysis times and a high sample throughput, thus leading to a significant reduction of the number of samples to be analysed in the laboratory and the costs. 相似文献
Currently, increasing amounts of end-of-life (EoL) electronic products are being generated due to their reduced life spans and the unavailability of suitable recycling technologies. In particular, waste printed circuit boards (PCBs) have become of global concern with regard to environmental issues because of their high metal and toxic material contents, which are pollutants. There are many environmental threats owed to the disposal of electronic waste; off-gasses, such as dioxins, furans, polybrominated organic pollutants, and polycyclic aromatic hydrocarbons, can be generated during thermal treatments, which can cause serious health problems if effective off-gas cleaning systems are not developed and improved. Moreover, heavy metals will dissolve, and release into the ground water from the landfill sites. Such waste PCBs contain precious metals which are of monetary value. Therefore, it is beneficial to recover the metal content and protect the environment from pollution. Hydrometallurgy is a successful technique used worldwide for the recovery of precious metals (especially gold and silver) from ores, concentrates, and waste materials. It is generally preferred over other methods because it can offer high recovery rates at a relatively low cost. This article reviews the recent trends and developments with regard to the recycling of precious metals from waste PCBs through hydrometallurgical techniques, such as leaching and recovery.
Marine species carried by the ships’ ballast waters are a potentially serious environmental problem. Many strategies are being
adopted to minimize the transfer of invasive or pathogenic marine species between different aquatic ecosystems. This problem
is often addressed by using biocides for ballast water treatment; however, the biocide could be dangerous to native organisms
once the ballast water is discharged. Chemical treatments such as chlorination and addition of glutaraldehyde could cause
problems related to toxicity and application costs. The search for new effective molecules with a low environmental impact
is pressing. This paper presents data from a preliminary efficacy screening of a promising molecule derived from alkylated
naphtoquinones on a battery of ballast water model organisms. Results show that this new molecule is very effective in the
absence of light and is extremely photodegradable (half-life <6 h). It can thus be easily degraded when released in the environment.
Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar Italy-Japan held in November 2004. 相似文献
Landfill sites have been the most common way of eliminating solid urban waste, as well as that of public and mining wastes.
Landfill sites are a constant source of environmental pollution and wind is the most important contributing factor to air
pollution, due to the erosion which it produces over the landfill site surfaces, transporting dust away from the source point.
This causes serious risks for human health and general dirt in the surrounding areas of the landfill site. The result of dust
air pollution produced in a landfill site is analysed through CFD3D (Computational Fluid Dynamics) by joining the LIDAR (Light
Detection and Ranging) technique and Ansys CFX 10.0 software. The CFD simulations determine the wind velocity distribution
on the landfill site surface and the different particle threshold friction velocities which determine the dust emission in
multiphase simulations (air-particles). These simulations are validated from field data obtained in three measurement programmes
for each type of landfill site surface treatment which has been studied. It was determined that the superficial landfill site
treatment with the lowest air pollution is tall grass and bushes. The methodology used can be applied to the dust emission
calculation in the design or evaluation of other landfill sites. 相似文献
This study highlights the health status of frogs in coffee plantations of Western Ghats. Coffee is one of the major commercial crops in the Western Ghats of India. In these plantations, farmers extensively use agrochemicals including pesticides and synthetic fertilisers. The practice of agrochemical usage can negatively affect non-target organisms like amphibians. The area has reported many amphibian species living in and around plantations. A total of 334 frogs from reference sites (10 abnormal frogs) and a total of 258 frogs (19 abnormal frogs) were collected from contaminated sites. We considered major biomarkers like hepato-somatic index, gonado-somatic index, morphological abnormalities and acetylcholinestarse activities for evaluating the health status of frogs. In our study, the hepato-somatic index and gonado-somatic index were found to be higher in a grochemical contaminated sites. Whereas, acetycholine esterase activity in brain and liver tissues of frogs in contaminated sites were low compared to reference sites. High rate of incidence of morphological abnormality (7.36%), increased hepato-somatic index (14.86%) and gonado-somatic index (male; 8.88% and female; 17.51%) and low acetylcholine esterase activities in brain (41.5%) and liver (46.9%) indicates the lower health status of frogs living in coffee plantations that are regularly treated with agrochemicals. 相似文献
The relative abundance of organisms from different taxa provides information about ecosystem health and diversity. When the numbers of sampled organisms are modelled as Poisson counts, and the sample volumes are not uniform, variance for the proportion attributable to each taxon is difficult to compute. We present a method for computing approximate variances for this situation. The point estimates and their standard errors reduce to the standard multinomial maximum likelihood results when sample volumes are uniform. Further, given initial estimates of population densities for the taxa of interest, optimal sample volumes can be computed. The methods are illustrated for zooplankton counts from Andrus Lake, Michigan. 相似文献
Electronic waste (e-waste) poses a major public health threat for developing countries’ populations. The hazards of e-waste are exacerbated by crude recycling methods. In this study, the presence of metals in e-waste samples obtained from Lagos, Nigeria, was assessed using atomic absorption spectrometry. The effect of e-waste on Escherichia coli (E. coli) PQ-37 genomic integrity was evaluated using the SOS chromotest. The means of metal concentrations in the evaluated samples were 16 (cadmium), 7.3 (nickel), 11 (chromium), 20 (lead), 3100 (iron), 90 (zinc), and 2000 (copper) μg_L?1. Damage to E. coli deoxyribonucleic acid (DNA) increased proportionally to the metal concentrations. Significant amounts of DNA damaging agents from inadequately processed e-waste are present in the studied environment, which will have implications for adverse effects on public and ecological health. Existing policies against dumping of toxic materials in susceptible communities should be enforced. 相似文献
A slack heap in Saxony serves as an example for the model procedure of evaluation heterogeneous waste sites via sampling as well as statistical and geostatistical data analysis. This paper demonstrates the usefulness of the known regulations for sampling and of the tried and proven geostatistical methods developed for assessing homogeneous wastes and the concornitantly contaminated soil. Emphasized here are the contents of iron and sulfur. Considered in addition are the concentrations of arsenic and the heat loss. To establish a conclusion, the variograms of the original data are used to evaluate the waste site in different directions and at determined depths. With the aid of a spot interpolation, further data can be calculated for additional sites which have not been sampled and can be used consequently for displaying the spatial variability. Finally, the statistical data analysis is applied using the standard methods of random sampling as an alternative to the geostatistical modeling. In this manner, the consequences for the sampling strategy can be demonstrated. 相似文献
Organic-contaminated soils are a major health issue because pollutants can be transferred to waters, air, and living organisms. Many remediation technologies have been developed, yet single methods are usually not fully efficient due to the wide diversity of soil and pollutant properties. Therefore, combining several methods has recently shown wider application range, higher efficiency, and better economic benefits. Here we compare combined remediation technologies to clean organic-contaminated soils, with focus on physical–chemical, physical–chemical-biological, and biological-microbial methods. Physical–chemical methods are the most widely used due to their high efficiency, yet they are costly, and they alter soil properties. These issues can be alleviated by adding a biological treatment. Combined biological-microbial methods are more recent and rely on bioengineering.
• Diversity and detection methods of pathogenic microorganisms in sludge.• Control performance of sludge treatment processes on pathogenic microorganisms.• Risk of pathogen exposure in sludge treatment and land application. The rapid global spread of coronavirus disease 2019 (COVID-19) has promoted concern over human pathogens and their significant threats to public health security. The monitoring and control of human pathogens in public sanitation and health facilities are of great importance. Excessive sludge is an inevitable byproduct of sewage that contains human and animal feces in wastewater treatment plants (WWTPs). It is an important sink of different pollutants and pathogens, and the proper treatment and disposal of sludge are important to minimize potential risks to the environment and public health. However, there is a lack of comprehensive analysis of the diversity, exposure risks, assessment methods and inactivation techniques of pathogenic microorganisms in sludge. Based on this consideration, this review summarizes the control performance of pathogenic microorganisms such as enterovirus, Salmonella spp., and Escherichia coli by different sludge treatment technologies, including composting, anaerobic digestion, aerobic digestion, and microwave irradiation, and the mechanisms of pathogenic microorganism inactivation in sludge treatment processes are discussed. Additionally, this study reviews the diversity, detection methods, and exposure risks of pathogenic microorganisms in sludge. This review advances the quantitative assessment of pathogenic microorganism risks involved in sludge reuse and is practically valuable to optimize the treatment and disposal of sludge for pathogenic microorganism control. 相似文献
Metal in the environment arises from both natural sources and human activities. Toxic metals in air, soil, and water have become a global problem. They are potential hazards to aquatic, animal, and human life because of their toxicity, bioaccumulative, and non-biodegradable nature. The major impacts of metal pollutants can be stated as ecosystem contamination and health problems of exposed human populations. Those problems have been a cause of increasing public concern throughout the world. Some trace metals are used by living organisms to stabilize protein structures, facilitate electron transfer reactions, and catalyze enzymatic reactions. But even metals that are biologically essential can be harmful to living organisms at high levels of exposure. An increasing concentration of heavy metals in the environment can modify mineral and enzyme functions of human beings. During the last two decades, the interest in using bioindicators as monitoring tools to assess environmental pollution with toxic metals has increased. Bioindicators are flora and fauna members, which are collected and analyzed to measure the levels of metal contaminants. Bioindicators therefore identify health hazards. Various living organisms, such as microbes, fungi, plants, animals, and humans, are used to monitor toxic metals from air, water, sediment, soil, and food chain. Here, we review recent bioindicators, toxicity assessment, and ecological effects. 相似文献
Abstract: Native European freshwater crayfish (Astacida, Decapoda) are under severe pressure from habitat alteration, the introduction of nonindigenous species, and epizootic disease. Crayfish plague, an acute disease of freshwater crayfish caused by the fungus-like agent Aphanomyces astaci , was introduced into Europe in the mid-nineteenth century and is responsible for ongoing widespread epizootic mortality in native European populations. We reviewed recent developments and current practices in the field of crayfish pathology. The severity of crayfish plague has resulted in an overemphasis on it. Diagnostic methods for detecting fungi and fungal-like agents, and sometimes culturing them, are frequently the sole techniques used to investigate disease outbreaks in European freshwater crayfish. Consequently, the causes of a significant proportion of outbreaks are undetermined. Pathogen groups well known for causing disease in other crustaceans, such as viruses and rickettsia-like organisms, are poorly understood or unknown in European freshwater crayfish. Moreover, the pathogenic significance of some long-known pathogens of European freshwater crayfish remains obscure. For effective management of this culturally significant and threatened resource, there is an urgent need for researchers, diagnosticians, and resource managers to address the issue of disease in European freshwater crayfish from a broader perspective than has been applied previously. 相似文献
Temperature profiles within a mine waste rock dump undergoing pyritic oxidation have been used to estimate the rate of oxidation and the sites where oxidation was occurring. The waste rock dump is located at the abandoned Rum Jungle mine site in Northern Australia and was a major source of pollution to the local river system. The dump was rehabilitated in 1983-84 by reshaping to reduce erosion and covering with clay and soil to reduce infiltration of water.Heat source distributions were derived from temperature profiles measured in the dump. The oxidation of pyritic material is the main cause of heat in the dump, hence the rate and location of oxidation can be obtained from the distribution of heat sources. A comparison of the heat source distributions before and after rehabilitation showed that rehabilitation greatly reduced or stopped the oxidation of pyrite in the dump. 相似文献