Towards Productive Cities: Environmental Assessment of the Food‐Energy‐Water Nexus of the Urban Roof Mosaic

Cities are rapidly growing and need to look for ways to optimize resource consumption. Metropolises are especially vulnerable in three main systems, often referred to as the FEW (i.e., food, energy, and water) nexus. In this context, urban rooftops are underutilized areas that might be used for the production of these resources. We developed the Roof Mosaic approach, which combines life cycle assessment with two rooftop guidelines, to analyze the technical feasibility and environmental implications of producing food and energy, and harvesting rainwater on rooftops through different combinations at different scales. To illustrate, we apply the Roof Mosaic approach to a densely populated neighborhood in a Mediterranean city. The building‐scale results show that integrating rainwater harvesting and food production would avoid relatively insignificant emissions (13.9–18.6 kg CO₂ eq/inhabitant/year) in the use stage, but their construction would have low environmental impacts. In contrast, the application of energy systems (photovoltaic or solar thermal systems) combined with rainwater harvesting could potentially avoid higher CO₂ eq emissions (177–196 kg CO₂ eq/inhabitant/year) but generate higher environmental burdens in the construction phase. When applied at the neighborhood scale, the approach can be optimized to meet between 7% and 50% of FEW demands and avoid up to 157 tons CO₂ eq/year. This approach is a useful guide to optimize the FEW nexus providing a range of options for the exploitation of rooftops at the local scale, which can aid cities in becoming self‐sufficient, optimizing resources, and reducing CO₂ eq emissions.     

北方半干旱集雨补灌旱作区节水农业发展模式

内蒙古准格尔旗集雨补灌旱作节水农业示范区地处黄土高原北部砒砂岩区,是我国水土流失最严重地区之一,集雨补灌是缓解当地干旱缺水的唯一途径.目前该区很多地方雨水收集利用缺乏整体研究,工程规划和生产布局有一定盲目性.在分析准格尔旗示范区生态、经济、社会等条件的基础上,总结出以集雨补灌为中心的旱作增产技术体系,确定了集雨高效种植型、集雨生态畜牧型和庭院集雨经济型3种模式,提出了示范区雨水综合利用需水量标准,并对3种模式在示范区运行3年来的经济、社会和生态效果进行了评价.     

黄土塬地区集雨窖水水源地优选

为提高黄土塬地区窖水水质,保证窖水饮用安全,集雨水源地的选择势在必行。本文通过应用主成分分析法,研究了优质集雨水源地和决定水质的控制指标。结果表明,在不同类型集雨水源地中,水泥地面和瓦屋面的综合主成分得分分别为-3.350和-1.945,污染程度分级结果为轻度,是集雨的最佳场地;COD、NH4+-N、TP、SS和粪大肠菌群在主成分中具有高荷载值;集雨水受有机物质、地表尘土、人畜粪便污染明显,与人为活动密切相关。最后,就集雨水源地在政策法规、水质保护技术体系、水质检测和保护等方面提出了改善措施和建议。     

Enteric Viruses of Humans and Animals in Aquatic Environments: Health Risks, Detection, and Potential Water Quality Assessment Tools

Waterborne enteric viruses threaten both human and animal health. These pathogens are host specific and cause a wide range of diseases and symptoms in humans or other animals. While considerable research has documented the risk of enteric viruses to human health from contact with contaminated water, the current bacterial indicator-based methods for evaluation of water quality are often ineffectual proxies for pathogenic viruses. Additionally, relatively little work has specifically investigated the risk of waterborne viruses to animal health, and this risk currently is not addressed by routine water quality assessments. Nonetheless, because of their host specificity, enteric viruses can fulfill a unique role both for assessing health risks and as measures of contamination source in a watershed, yet the use of animal, as well as human, host-specific viruses in determining sources of fecal pollution has received little attention. With improved molecular detection assays, viruses from key host groups can be targeted directly using PCR amplification or hybridization with a high level of sensitivity and specificity. A multispecies viral analysis would provide needed information for controlling pollution by source, determining human health risks based on assessments of human virus loading and exposure, and determining potential risks to production animal health and could indicate the potential for the presence of other zoonotic pathogens. While there is a need to better understand the prevalence and environmental distribution of nonhuman enteric viruses, the development of improved methods for specific and sensitive detection will facilitate the use of these microbes for library-independent source tracking and water quality assessment tools.     

Enteric viruses of humans and animals in aquatic environments: health risks, detection, and potential water quality assessment tools.

Waterborne enteric viruses threaten both human and animal health. These pathogens are host specific and cause a wide range of diseases and symptoms in humans or other animals. While considerable research has documented the risk of enteric viruses to human health from contact with contaminated water, the current bacterial indicator-based methods for evaluation of water quality are often ineffectual proxies for pathogenic viruses. Additionally, relatively little work has specifically investigated the risk of waterborne viruses to animal health, and this risk currently is not addressed by routine water quality assessments. Nonetheless, because of their host specificity, enteric viruses can fulfill a unique role both for assessing health risks and as measures of contamination source in a watershed, yet the use of animal, as well as human, host-specific viruses in determining sources of fecal pollution has received little attention. With improved molecular detection assays, viruses from key host groups can be targeted directly using PCR amplification or hybridization with a high level of sensitivity and specificity. A multispecies viral analysis would provide needed information for controlling pollution by source, determining human health risks based on assessments of human virus loading and exposure, and determining potential risks to production animal health and could indicate the potential for the presence of other zoonotic pathogens. While there is a need to better understand the prevalence and environmental distribution of nonhuman enteric viruses, the development of improved methods for specific and sensitive detection will facilitate the use of these microbes for library-independent source tracking and water quality assessment tools.     

Prevalence of Virulence Genes Associated with Pathogenic Escherichia coli Strains Isolated from Domestically Harvested Rainwater during Low- and High-Rainfall Periods

The possible health risks associated with the consumption of harvested rainwater remains one of the major obstacles hampering its large-scale implementation in water limited countries such as South Africa. Rainwater tank samples collected on eight occasions during the low- and high-rainfall periods (March to August 2012) in Kleinmond, South Africa, were monitored for the presence of virulence genes associated with Escherichia coli. The identity of presumptive E. coli isolates in rainwater samples collected from 10 domestic rainwater harvesting (DRWH) tanks throughout the sampling period was confirmed through universal 16S rRNA PCR with subsequent sequencing and phylogenetic analysis. Species-specific primers were also used to routinely screen for the virulent genes, aggR, stx, eae, and ipaH found in enteroaggregative E. coli (EAEC), enterohemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC), and enteroinvasive E. coli, respectively, in the rainwater samples. Of the 92 E. coli strains isolated from the rainwater using culture based techniques, 6% were presumptively positively identified as E. coli O157:H7 using 16S rRNA. Furthermore, virulent pathogenic E. coli genes were detected in 3% (EPEC and EHEC) and 16% (EAEC) of the 80 rainwater samples collected during the sampling period from the 10 DRWH tanks. This study thus contributes valuable information to the limited data available regarding the ongoing prevalence of virulent pathotypes of E. coli in harvested rainwater during a longitudinal study in a high-population-density, periurban setting.     

Cumulative exposure and dietary risk assessment of phthalates in bottled water and bovine milk samples: A preliminary case study in Tamil Nadu,India

Exposure to phthalates may cause adverse health effects in wildlife and humans. Study on phthalates exposure and risk is limited in the Indian context. Therefore, this preliminary investigation was performed to ascertain the phthalates exposure through bottled water and milk among the Indian sub-population. Phthalates were extracted from water and milk by solid-phase and ultrasonication methods, respectively, and analysis was performed using gas chromatography–mass spectrometry. Total phthalates in bottled water and milk were in the range of 39–7820 ng/L and 56–686 ng/g, respectively, with the highest contribution from diethylhexyl phthalate (DEHP). A substantial increase in phthalates concentration in bottled water was observed with increased shelf life. Total mean phthalates in packed milk (245 ng/g) and raw milk (134 ng/g) shows potential enrichment during “farm to table” process. Among phthalates, the lowest risk was expected from diethyl phthalate, whereas the highest risk was observed for DEHP with cumulative dietary exposure of 0.23 μg/kg bw/day (median). The human health risk based on tolerable daily intake and reference dose was found safe. This is the first study reporting phthalates migration in packed commodities from a developing country, India, which further warrants extensive phthalates exposure assessment to understand its effect on public health.     

Health Risk from the Use of Roof-Harvested Rainwater in Southeast Queensland,Australia, as Potable or Nonpotable Water,Determined Using Quantitative Microbial Risk Assessment

A total of 214 rainwater samples from 82 tanks were collected in urban Southeast Queensland (SEQ) in Australia and analyzed for the presence and numbers of zoonotic bacterial and protozoal pathogens using binary PCR and quantitative PCR (qPCR). Quantitative microbial risk assessment (QMRA) analysis was used to quantify the risk of infection associated with the exposure to potential pathogens from roof-harvested rainwater used as potable or nonpotable water. Of the 214 samples tested, 10.7%, 9.8%, 5.6%, and 0.4% were positive for the Salmonella invA, Giardia lamblia β-giardin, Legionella pneumophila mip, and Campylobacter jejuni mapA genes, respectively. Cryptosporidium parvum oocyst wall protein (COWP) could not be detected. The estimated numbers of Salmonella, G. lamblia, and L. pneumophila organisms ranged from 6.5 × 10¹ to 3.8 × 10² cells, 0.6 × 10° to 3.6 × 10° cysts, and 6.0 × 10¹ to 1.7 × 10² cells per 1,000 ml of water, respectively. Six risk scenarios were considered for exposure to Salmonella spp., G. lamblia, and L. pneumophila. For Salmonella spp. and G. lamblia, these scenarios were (i) liquid ingestion due to drinking of rainwater on a daily basis, (ii) accidental liquid ingestion due to hosing twice a week, (iii) aerosol ingestion due to showering on a daily basis, and (iv) aerosol ingestion due to hosing twice a week. For L. pneumophila, these scenarios were (i) aerosol inhalation due to showering on a daily basis and (ii) aerosol inhalation due to hosing twice a week. The risk of infection from Salmonella spp., G. lamblia, and L. pneumophila associated with the use of rainwater for showering and garden hosing was calculated to be well below the threshold value of one extra infection per 10,000 persons per year in urban SEQ. However, the risk of infection from ingesting Salmonella spp. and G. lamblia via drinking exceeded this threshold value and indicated that if undisinfected rainwater is ingested by drinking, then the incidences of the gastrointestinal diseases salmonellosis and giardiasis are expected to range from 9.8 × 10° to 5.4 × 10¹ (with a mean of 1.2 × 10¹ from Monte Carlo analysis) and from 1.0 × 10¹ to 6.5 × 10¹ cases (with a mean of 1.6 × 10¹ from Monte Carlo analysis) per 10,000 persons per year, respectively, in urban SEQ. Since this health risk seems higher than that expected from the reported incidences of gastroenteritis, the assumptions used to estimate these infection risks are critically examined. Nonetheless, it would seem prudent to disinfect rainwater for use as potable water.Roof-harvested rainwater has received significant attention as a potential alternative source of potable and nonpotable water in regions where water is scarce (37). To encourage the use of roof-harvested rainwater, governmental bodies of many countries, such as Australia, Denmark, Germany, India, and New Zealand, are providing subsidies to residents to encourage the use of rainwater for domestic purposes. The use of rainwater is quite common in Australia, particularly in rural and remote areas, where reticulated mains or town water is not available. Recent water scarcity in several capital cities prompted the use of rainwater as an alternative source. For instance, the Queensland State Government initiated the “Home Water Wise Rebate Scheme,” which provides subsidies to Southeast Queensland (SEQ) residents who use rainwater as nonpotable water for domestic purposes (49). Over 260,000 householders were granted subsidies up to December 2008, when the scheme was concluded.There is a general community feeling that roof-harvested rainwater is safe to drink, and this is partially supported by limited epidemiological evidence (26). Some studies have reported that roof-harvested rainwater quality is generally acceptable for use as potable water (13, 29). In contrast, the presence of potential pathogens, such as Aeromonas spp. Campylobacter spp., Campylobacter jejuni, Salmonella spp., Legionella pneumophila, Giardia spp., Giardia lamblia, and Cryptosporidium spp., in roof-harvested rainwater samples has been reported (2, 9, 34, 45, 47, 48). Such pathogens can cause gastrointestinal illness in humans, with nausea, vomiting, and/or diarrhea occurring within 12 to 72 h (Salmonella enterica serovar Typhimurium) to 9 to 15 days (Giardia lamblia) after ingestion of contaminated water. L. pneumophila can cause the respiratory infection pneumonia, and the fatality rate can be 50% in immunocompromised patients (57).Direct routine monitoring of the microbiological quality of source water for all possible pathogens is not economically, technologically, or practically feasible. Consequently, traditional fecal indicators, such as fecal coliforms, Escherichia coli, and enterococci, have long been used to determine the presence of pathogens. Most studies assess the quality of roof-harvested rainwater based on the numbers of these fecal indicators (13, 30). However, the major limitation in using fecal bacteria as indicators is their poor correlation with the presence of pathogenic microorganisms in water (2, 30). An alternative is the measurement of pathogens using traditional culture-based methods. However, there are several limitations of such methods, including the underestimation of the bacterial number due to the presence of injured or stressed cells (10) and the fact that certain microorganisms in environmental waters can be viable but not culturable (39). Culture-based methods are also generally laborious and costly. Recent advances in molecular techniques such as PCR technology enable rapid, specific, and sensitive detection of many pathogens. Advances in PCR methodology also enable the quantification of potential pathogens in source water that are otherwise difficult and/or laborious to culture using traditional microbiological methods. In view of this, we used binary PCR (presence/absence)- and quantitative PCR (qPCR)-based assays to first detect and then quantify zoonotic pathogens in samples from roof-harvested rainwater in SEQ residential houses.The aims of the research study were 2-fold: (i) to quantify the number and frequency of occurrence of Salmonella, G. lamblia, and L. pneumophila organisms in a range of domestic water tanks in SEQ by using qPCR-based methods and (ii) to apply quantitative microbial risk assessment (QMRA) analysis in order to estimate the risk of infection from exposure to these pathogens found in roof-harvested rainwater. The uniqueness of this study stems from the fact that instead of measuring fecal indicators, the pathogens that are capable of causing illness were quantified and this information was combined with QMRA to assess the human health risk of using roof-harvested rainwater as potable or nonpotable water.     

A dynamic assessment of water scarcity risk in the Lower Brahmaputra River Basin: An integrated approach

Many international river basins are likely to experience increasing water scarcity over the coming decades. This water scarcity is not rooted only in the limitation of resources, i.e. the shortage in the availability of freshwater relative to water demand, but also on social factors (e.g. flawed water planning and management approaches, institutional incapability to provide water services, unsustainable economic policies). Therefore, the assessment of water scarcity risks is not limited to the assessment of physical water supply and demand, but it requires also consideration of several socio-economic factors. In this study, we provide a comprehensive dynamic assessment of water scarcity risks for the Lower Brahmaputra river basin, a region where the hydrological impact of climate change is expected to be particularly strong and population pressure is high. The basin area of Brahmaputra River lies among four different countries: China, India, Bangladesh and Bhutan. For water scarcity assessment, we propose a novel integration of different approaches: (i) the assessment of water scarcity risk, considering complex social-ecological system; (ii) the analysis of dynamic behaviour of the system; (iii) exploration of participatory approach in which limited number of stakeholders identify the most relevant issues with reference to water scarcity risks and provide their preferences for the aggregation of risk assessment indicators. Results show that water scarcity risk is expected to slightly increase and to fluctuate remarkably as a function of the hazard signal. Social indicators show trends that can at least partially compensate the increasing trend of the drought index. The results of this study are intended to be used for contributing to planned adaptation of water resources systems, in Lower Brahmaputra River Basin.     

Environmental Risks at Finnish Shooting Ranges—A Case Study

We studied three Finnish shooting ranges in order to define the extent of the risks associated with elevated environmental concentrations of metals and PAHs. A scoring system revealed that lead, arsenic, and antimony were the most critical contaminants. On Site 3, the concentration of lead in groundwater exceeded the drinking water standard indicating evident health risks. For the remaining two sites we calculated Acceptable Daily Doses (ADD) based on the Reasonable Maximum Exposure (RME) approach and compared them with safe exposure levels. We also used a pharmacokinetic model to determine blood lead levels (PbBs). Risks to biota were assessed using ecological benchmarks and exposure and accumulation models. Prediction of leaching was based on laboratory tests and a distribution model. The health risk assessment for lead resulted in the maximum hazard quotient (HQ) of 1.2 whereas the HQs of As and Sb remained less than 1. Some exposure scenarios produced PbB estimates exceeding 10 μ g dl^?1 but based on the uncertainty analysis we expect the health risks to remain insignificant. However, leaching of contaminants presents a risk to groundwater quality. At site 1 the ecotoxicity-based HQs demonstrate high risks to soil biota, small mammals, terrestrial plants and aquatic organisms.     

Quantification of diarrhea risk related to wastewater contact in Thailand

Wastewater reuse contributes to closing the nutrient recycling loop as a sustainable way of managing water resources. Bangkok has over a thousand man-made drainage and irrigation canals for such purposes. Its use for agricultural and recreational purposes has a long tradition in rural and peri-urban areas. However, the continuation of these practices is increasingly questioned since potential health risks are an issue if such practices are not appropriately managed. The microbial and chemical quality of canal water has considerably deteriorated over the last decade, mainly because of discharged, untreated domestic and industrial wastewater. It is important to understand the health risks of wastewater reuse and identify risky behaviors from the most highly exposed actors promote the safe use of wastewater. This study assessed diarrhea infection risks caused by the use of and contact with wastewater in Klong Luang municipality, a peri-urban setting in Northern Bangkok, using quantitative microbial risk assessment. Wastewater samples were collected from canals, sewers at household level, and vegetables grown in the canals for consumption. Samples were also collected from irrigation water from the agricultural fields. Two protozoa, Giardia lamblia and Entamoeba histolytica, were quantified and analyzed by real-time PCR, exposure assessment was conducted, and finally, the risk of infection due to contact with wastewater in different scenarios was calculated. The results showed that canal water and vegetables were heavily contaminated with G. lamblia and E. histolytica. Infection risk was high in tested scenarios and largely exceeded the acceptable risk given by WHO guidelines.     

Hydrogeochemical evolution and risk assessment of human health in a riverbank filtration site,northeastern China

Intensive agriculture and industrial activities have resulted in contamination in rivers and groundwater quality, which threatens human health. In this study, we used comprehensive physiochemical indicators to assess the quality of groundwater used for drinking and irrigation in addition to the potential risks to local residents in a riverbank filtration site. Human health risks through drinking water intake and dermal contact were also estimated. Moreover, we analyzed the spatial distribution regularities of health risk values in a riverbank filtration site. The assessment results revealed that NH₄–N, NO₂–N, F^?, Mn, and As are main contaminants affecting groundwater quality and that 62% of the total samples is suitable for a variety of purposes. All groundwater in the study area is suitable for irrigation based on the sodium adsorption ratio (SAR), residual sodium carbonate (RSC), Na percentage (%Na), and U.S. Salinity Laboratory (USSL) and Wilcox diagrams. The health risk assessment suggests that residents in the study area are at high health risk, and women and children face higher risk than men in both non-carcinogenic and carcinogenic risks. The spatial distribution regularities of health risk values suggest that the human health risk value of each groundwater sample is different in the study area and has certain regularity. Therefore, effective measurements must be taken to address the groundwater contamination and to reduce the human health risks.     

Lifetime Risk of Fatal Occupational Injuries within Industries,by Occupation,Gender, and Race

Estimates of risk accumulated over a working lifetime are used to assess the significance of many workplace health hazards. Most studies which have estimated this risk have focused on a worker's lifetime risk of dying of a stated illness based on exposure to a hazard in a specific job. The concept, however, has not been widely applied to occupational injury deaths. This study examines the use of lifetime risk based on national fatal injury data from the Bureau of Labor Statistics (BLS) Census of Fatal Occupational Injuries (CFOI). Lifetime risks are defined by specific causal events for those groups identified as having the highest general lifetime risks. The lifetime risk model for injury used in this work can be compared with risk assessments for occupational illnesses. Fatal injury lifetime risk estimates will be useful in defining traumatic injury exposures that are appropriate for targeting research and prevention efforts needed to reduce the burden of work-related death within the United States. These estimates also provide a means of prioritizing traumatic injury research with fatal illness research, while providing the additional benefit of providing a means of informing workers of their fatal injury risks.     

Potential health risks assessment cognate with selected heavy metals contents in some vegetables grown with four different irrigation sources near Lahore,Pakistan

Carcinogenic and health hazard causing heavy metals have been increasing in our dietary stuffs due to large amount of industrial effluents being dumped in water bodies that are ultimately used for irrigation purposes. The study was aimed to assess and compare the mean concentrations of heavy metals (Cd, As and Pb) in soil and vegetables irrigated with four different sources (Ground water, river water, domestic sewage water and industrial untreated effluents and domestic waste water receiving drains) for the estimation of carcinogenic and non-carcinogenic health risk associated with them. Prepared samples were analyzed by through ICP-OES. Statistical analysis revealed that domestic sewage water and drains water usage for irrigation purposes leads to high values of Estimated Daily Intake (EDI) of metals through vegetation. To assess the carcinogenic effects values daily intakes, Total hazard quotients (THQs) and Health indexes (HI), while for carcinogenic effects, Total cancer risks (TCR) were determined. The results of present study revealed that the daily intakes of these metals are far less than that of permissible levels but their bio-accumulating behavior produce high risks to human health. The HI values revealed that waste water usage is producing the vegetables of high health risks. In adults, the HI of Phaseolus vulgaris, Spinacia oleracea, Brassica compestris, Raphnus sativus, Daucus carota and Solanum tuberosum assessed as 0.81, 1.52, 1.26, 0.12, 0.22, and 0.15 (ground water irrigation), 0.046, 0.75, 0.51, 0.68, 0.90 0.064 (River Ravi water irrigation), 1.23, 3.34, 4.81, 4.23, 1.41 and 3.43 (domestic sewage irrigation) and 3.04, 5.50, 6.08, 2.50, 5.34 and 5.13 (Drain waste water irrigation), respectively. It was observed that cancer risks of As exceeded the threshold (1 × 10^?4) in all i.e. ground river, domestic sewage and drain water grown vegetables, while, Cd and Pb were in permissible range.     

山地果园集雨-壤中防渗对水分入渗、分布和利用率的影响

集雨-壤中防渗技术是在起垄覆膜垄沟覆草技术的基础上提出的一项新技术.为了探讨集雨-壤中防渗技术在陕北黄土丘陵区山地果园的应用效果,在米脂县党塔苹果科技示范基地山地红富士苹果园布设对照(CK)、黄绵土夯实防渗(L_1)、红黏土防渗(R_1)、红黏土夯实防渗(R_2)4种处理,测定了不同防渗层类型的土壤容重、稳渗率以及不同处理的土壤水分、果实品质、产量和水分利用率.结果表明:红黏土夯实防渗层防渗效果最好,其土壤容重(1.61g·cm^-3)最高,持水量最低,稳定入渗率(0.02 mm·min^-1)最小,采用Kostiakov经验公式方程能很好地模拟不同防渗处理水分入渗特征.在整个苹果生长季节,不同防渗处理均能提高集雨沟下0~60 cm土层的土壤含水量,其中,R_2的含水量始终最高,在旱季可以达到苹果树生长发育适宜的含水量标准;壤中防渗处理60 cm土层以下20~30 cm范围内存在一个明显的"低湿层",但低湿层至200 cm土层的土壤含水量变化趋势较为稳定,较CK略有增加;集雨-壤中防渗处理能够提高果实产量和水分利用率、改善品质.其中,R_2处理的产量比CK提高了19.2%,优果率提高了26.5%,水分利用效率提高了24.5%.建议陕北黄土丘陵区山地苹果生产中大力推广集雨-壤中防渗技术.     

黄土高原集水农业研究进展

回顾了黄土高原集水农业理论与技术体系的研究成果．分析评价了集水农业的研究进展。随着黄土高原集水农业研究方法的改进、研究内容的深入、研究领域的扩充．提出了广义性集水农业研究范畴。在黄土高原集水农业理论研究的基础上．应加强微集雨微灌溉应用技术、现代集雨技术、计算机控制技术与集雨网络等高新技术手段的技术集成．以提高雨水汇集与利用效率。同时．黄土高原集水农业的研究已经从微生境条件下的农业生态系统延伸至区域生态环境保育。利用汇集雨水合理调配生态用水．进行小流域综合治理。农林牧综合发展。生态环境重建的集水型生态农业是黄土高原集水农业的发展趋势。     

美国、加拿大环境和健康风险管理方法

对目前美国和加拿大多个部门使用的风险评价与风险管理方法进行了全面回顾和综合分析,论述各种不同方法的特征,深入探讨各种管理方法的基础、利弊、使用经验,辨识环境、人类健康和职业健康风险综合方法中应该包含的要素,阐述风险管理目标的确定方法,以期为中国的环境风险管理提供经验。     

Evaluation of groundwater contamination for fluoride and nitrate in semi-arid region of Nirmal Province,South India: A special emphasis on human health risk assessment (HHRA)

The main aim of this study was to assess the groundwater quality and human health risks of fluoride and nitrate contamination in Nirmal Province, South India, where groundwater is the primary source for drinking water. Hazard quotient (HQ) and total hazard index (THI) were calculated to estimate the non-carcinogenic risk to men, women, and children using the most substantial method recommended by United States Environmental Protection Agency (USEPA). The results of the study reveal that 26% and 20.59% of groundwater samples have significantly high nitrate and fluoride concentrations, exceeding the maximum permissible limits set by Bureau of Indian Standards (45 mg/L and 1.5 mg/L, respectively). Therefore, ingestion of high fluoride and nitrate water could be the chief reason for health risk in the study region. The total non-carcinogenic health risks for men, women, and children ranged from 2.95E?01 to 4.07E+00, 3.49E?01 to 4.80E+00, and 3.99E?01 to 5.50E+00, respectively. Moreover, 67.65%, 79.41%, and 82.35% of the total collected groundwater samples exceeded the permissible limit for acceptable total health index (THI = 1) for men, women, and children, respectively. Therefore, the health risk assessment suggests that children face higher health risk than men and women in the study region.     

Risk assessment strategies for transgenic plants

Advances in recombinant DNA technology have created advantages for the development of plants with high agro-economical values. Since the production of transgenic plants, some issues concerning the safe use of these plants and their products have been under debate throughout the world. In this respect, the potential risks and benefits of transgenic plants need to be evaluated objectively. Risk assessment of transgenic crops is a basic prerequisite for monitoring the possible risks that could arise upon the release and use of transgenic plants. To get a meaningful tool for decision making, risk assessment needs to be carried out in a scientific sound and transparent manner. There are specific governmental regulations in many countries for the safety assessment of genetically modified (GM) crops. Furthermore, there are some international agreements, which regulate the cultivation and commercialization of transgenic plants and their derivatives. Internationally accepted risk assessment strategies have been performed to evaluate the safe use of a large variety of GM crops. The main objectives of these regulations and risk assessment strategies are focused to protect human/animal health and the environment.     

Spatial distribution,exposure, and potential health risk assessment from nitrate in drinking water from semi-arid region of South India

Abstract

Elevated nitrate concentration in groundwater is a worldwide problem. Continuous exposure to high levels of nitrate in groundwater may cause adverse health effects among residents who use groundwater for consumption. Therefore, this study was conducted to identify the nitrate distribution and its potential health risk assessment from semi-arid region of Peddavagu in Central Telangana (PCT), South India. Groundwater samples were collected from thirty five locations and analyzed for nitrate and other water quality parameters. Nitrate (NO₃^-) in groundwater was observed to vary from 17 to 120?mg/L, with a mean of 58.74?mg/L. About 57% of samples exceeded the maximum acceptable limit of Indian drinking water standard. About, 40% of groundwater samples drinking water quality index (DWQI) is good, while 60% of groundwater falls in poor quality for drinking purposes. Health risk maps were created based on hazard quotient to quantify the potential health risk of the residents using US Environmental Protection Agency (US EPA) health risk assessment model. Health risk assessment revealed that mean total hazard index (HI_total) for men, women, and children were found as 1.42E?+?00, 1.67E?+?00, and 1.95E?+?00, respectively. Results exhibited that children are at high health risk than men and women in the PCT. Further, the human exposure to the NO₃^- contaminated water was above the critical limit of non-carcinogenic risk.