pollution

摘要： Global water shortage is caused not just by the physical scarcity of water, but also by gradual deterioration of the quality of water resources such as lakes, streams and rivers with heavy metals. This present study evaluated the status of Mn, Fe, Cr, Cu, Ni, As, Zn, Pb and Cd in sediments from the lower Orange River by Inductively Coupled Plasma Atomic Emission Spectrometry technique by collecting a total of eleven samples, each weighing 1 - 2 kg at the depth of 15 - 20 cm from two observations sites along the lower Orange River and applying pollution indicators such as contamination factor(CF), pollution load index(PLI), index of geo-accumulation(Igeo) and enrichment factor(EF) to assay the nature and extent of heavy metals contamination in sediments. The sequence of the total heavy metal content in descending order was Fe > Mn > Cr > As > Zn > Ni > Cu > Pb > Cd. The results of CF and Igeo showed Mn, Cd, Ni, Zn and Pb were minor sources of sediment contamination since most of the samples were unpolluted and moderately polluted by these metals. However, most sediments were moderate to considerably polluted with Cr, As and Fe suggesting that these were the major pollution sources. The value of PLI at one of the two observation sites was equivalent to the value of baseline level, while the next site indicted quality deterioration of the sediments. The EF revealed that Cr was moderately enriched and arsenic (As) significantly enriched in all the sediments, which suggested contamination due to anthropogenic intervention. Hence, it is recommended that sediment quality be evaluated on a regular basis to avoid further deterioration of the Orange River’s health, which might have detrimental repercussions for both aquatic life and local communities along the river.

摘要： Water represents a critical nutrient, the absence of which will be lethal within days. Water’s importance for the prevention of nutrition-related noncommunicable diseases has received more attention recently. There are major gaps in knowledge related to the measurement of total fluid intake and hydration status at the population level. It is poorly understood the effects of chronic mild dehydration and fluid consumption on specific health outcomes including obesity. Urolithiasis is the only disorder that has been consistently associated with chronic low daily water intake. Water is an essential nutrient required for life, but until now, it was considered mainly as a universal solvent, which served to prepare the broth of life inside the cells, but the function of water now takes unusual importance with our discovery of the unsuspected ability of the human body to transform the power of light into chemical energy by dissociating the molecule from water, as it happens in plants. The process that we replicated in the laboratory for the first time in 2007, represents a light at the end of the tunnel, in the growing and serious problem of contamination of the mysterious and vital liquid that we call water.

摘要： The present article is a review study on the types of rare earth elements(REEs),environmental and biological effects as well as the sources of emission of these elements as pollution in nature.The purpose of this study is to provide a vision in environmental planning and control of pollution caused by REEs.The evaluation of rare earth elements was studied in human life and its environmental and biological effects,which have particular importance and are entering the life cycle through industrial and mining pollution sources.Since mining activities intensify the dispersion of these elements in the environment and the existence of industrial factories located around urban drainage system plays a unique role in creating and spreading pollution caused by rare earth elements;As a result,two case studies were conducted on two mining and industrial areas.The first case is the Choghart mine in Yazd province as an example of mining pollution,and the second case study is performed on the Kor river as an example of industrial pollution which is caused by industrial activities around it,Then the results are well explained to show both two environments of litho and hydro.Due to this fact that produced environmental pollution can cause exchange pollutant compounds with the surrounding environment besides its long-lasting destructive effects;It can cause irreversible biological effects on living organisms.By targeting this evaluation,several techniques can be proposed to prevent the entry and dispersal of rare earth elements from pollution sources besides methods to reduce the damage of these elements to the ecosystem.

摘要： Pollution of the water bodies poses a great threat to hu­mans life and the aquatic ecosystem.Worldwide surface water bodies(rivers and canals)are exposed to pollution because of discharging untreated liquid wastes.Anthropo­genic activities,including domestic activities,especially sewage disposal practices,industrial,and agricultural activities,may deteriorate both water quantity and qual­ity representing a potential threat to the communities.Pollutants effect may vary depending on their types and source.Therefore,various pollutants could be detected in surface waters,the fate of these contaminants is mainly determined to large extent by adsorption mechanisms and biological transformations during their underground flow path which known by riverbank filtration(RBF)[1].

摘要： The Makiso municipality is located in an urban area influenced by a very high rate of land occupation by houses. This land use has an impact on the quality of the groundwater exploited by wells and springs. This groundwater helps to make up for the deficit caused by the lack of a water distribution network. It is also threatened by pollution from human activities. In order to protect the groundwater in Makiso municipality from pollution, the study of the intrinsic vulnerability assessment in the aquifers was carried out by applying the DRASTIC method and the Geographic Information System (GIS). The results obtained using this method were grouped into two degrees of vulnerability (medium and high), with variations in DRASTIC indices of [141 - 145] for the medium degree and [146 - 175] for the high degree. The high vulnerability class is the most dominant, with a percentage of 96.5% of the study area. The medium vulnerability class, which represents 3.5% of the area of the Makiso municipality, is mainly located in the western (medical plateau district), central (Lualaba district) and southern (commercial district) sectors in the form of isolated pockets. A comparison of the nitrate distribution map with the final vulnerability map shows that the areas defined as highly vulnerable by the DRASTIC method and the areas with high nitrate concentrations (above 0.11 mg/l) are in agreement. On the other hand, there are other areas with low nitrate concentrations (below 0.05 mg/l) which correspond to the high vulnerability indices.

摘要： The Gounti Yéna valley, the subject of this study, is a tributary of the Niger River, it is the main watercourse that divides the left bank of the city of Niamey into two unequal parts. The surface area of its watershed is estimated at about 62 Km2. The objective of the present study is on the one hand to evaluate the current state of the physico-chemical and bacteriological quality of the water of Gounti Yéna basin, and on the other hand to define the risks of water pollution and its origin in the face of the phenomenon of rising water table of this basin. In order to carry out this work, we proceeded to a study of the evolution of the physicochemical and bacteriological parameters of the water of the basin of Gounti Yéna during the period going from November 2020 to October 2021, at the level of four points of sampling chosen from the upstream to the downstream of the basin. The results obtained showed that the physico-chemical quality of the water in Gounti Yéna basin is influenced by the lithology of the watershed, climatic factors (rainfall and temperature) and anthropic actions. This study also highlighted the presence of fecal contamination in the water of the Gounti Yéna basin, with a greater degree of emphasis during the rainy season. This contamination remains a concern and may constitute a health risk.

摘要： 1.Introduction As one of the milestone documents on global air quality management,the World Health Organization(WHO)health guidelines have been periodically adopted and published air quality guidelines(AQGs)following systematic reviews on evidence from medical and public health studies,and through extensive expert panel discussion and consultation.Since 1987,WHO has periodically issued health-based air quality guidelines—Air Quality Guidelines for Europe(hereafter referred to as“AQGs(1987)”)to assist governments and civil society to reduce human exposure to air pollution and its adverse effects.1 In 2006,a global edition of the updated AQGs—WHO Air Quality Guidelines Global Update 2005(hereafter referred to as“AQGs(2005)”)was released.2 With increasing evidence on air pollution attributed heath risk and adverse effects,the global air quality guidelines were further updated and accomplished in 2021.2-3 AQGs(1987)provided health-based guideline levels for the major air pollutants,including carbon monoxide(CO),lead,nitrogen dioxide(NO2),ozone(O3),sulfur dioxide(SO2)and total suspended particulate(TSP)matter.However,in AQGs(2005),TSP was then replaced by particulate matter(PM)with aerodynamic dimeter less than 2.5µm(PM2.5)and PM with aerodynamic dimeter equal or less than 10µm,albeit without the provision of numerical guideline values.2 In each edition of the guidelines,air quality criteria values have been derived for recommendations protecting human populations from the adverse impacts of air pollution exposure,and guidelines are of significant importance for low-and middle-income countries(LMICs)in reducing air pollution exposure and resulting in beneficial impacts on health.

摘要： Prof.Huang received her doctorate degree in Environmental Health from Harvard T.H.Chan School of Public Health in 2003.She then worked at the Health Effects Institute based in Bost on mainly resp on sible for managi ng air pollution health studies in Asia between 2003-2007.She joined Peking University in 2008 and is now the Deputy Director of Peking University Institute of Environmental Medicine,and Principal Investigator of Key Laboratory of Molecular Cardiovascular Sciences of Ministry of Education,Peking University.

摘要： Metal toxicity and soil salinity at excessive levels in soils are toxic to plants. The main objective of this study was to demonstrate the effects of water salinity (NaCl) and heavy metal concentration on germination and seedling characteristics of maize and beans seeds. Different concentrations of NaCl (0 to 35000 mg/L) and Zn2+, Cu2+ and Pb2+ with concentrations 0 to 600 μmol/L each were used separately. These solutions were used to irrigate maize and bean seeds for 30 days. Data was taken daily for the following parameters;“the number of germinated seeds, shoot length, shoot circumference, leaf area index, leaf colors, senescence, and disease occurrences.” The crops were uprooted at the end of the 30 days and their wet masses were measured and recorded. Results indicated that seed germination reduced with an increase in the concentration of NaCl for both maize and beans with 0% germination recorded in concentrations > 5000 mg/L. The same trends were observed for other parameters, the shoot length, the leaf area index, and the shoot circumference. “For heavy metals, the trends were similar. Beans growth was more affected by Zn and Cu but maize growth was more affected by Pb.” The dry masses and wet masses of the crops with higher concentrations of metals and salts were very low compared to the control experiments. For the effects of salinity and heavy metals on beans and maize seeds, there was a significant difference (P ≤ 0.001) between all tested concentrations and the control for all growth parameters monitored. It was concluded from the results that salinity and heavy metals affect the germination and seedling characteristics of maize and beans;though some metals are essential, their presence in higher concentrations instead cause harm.

摘要： The unquenchable demand for rock materials has attracted many companies within the building and construction sector to invest in stone quarrying. However, this has brought about environmental impacts with health threats to people. There is a paucity of information about the magnitude of pollution on air and water and how it varies with quarry sites. This study, therefore, investigated the physical impacts of quarrying on air and water and explored the in-situ mitigations to undesirable effects due to stone quarrying. Four active quarry sites were identified. Field measurements of dust (particulate matter) were conducted within the four quarry sites and in the nearby community. Water samples were collected from quarry pits and nearby shallow wells for laboratory analysis of water quality. Statistical Analysis of Variance (ANOVA) was used to test for differences in pollution across the four studied sites. Results revealed that, amidst the use of wet crushing and water sprinkling on bare surfaces, dust emission was higher than the recommended permissible standards levels with a significant variation across the quarry sites with ANOVA (P-value = 0.003) for PM 2.5 and (P-value = 0.04366) for PM 10. Water pollution was mainly contributed by the non-permissive levels of nitrates, chromium, and pH. Polluted air and water are associated with sparking off health threats to the users in the community. In conclusion, quarry companies should strengthen the already existing mitigation of dust suppression. The study recommends additional measures such as treating quarry pit water before discharging to the open environment to enhance environmental protection against the accumulating undesirable quarry impacts.