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Analysis of the Stringency of Drinking Water Quality Standards of Bangladesh in Comparison to the USA, EU, Japanese, and Indian Standards
2018
Islam, Kamrul | Zahra, Fatima-Tuz- | Chowdhury, Md. Arif | Biswas, Suvo Moy
Water is one of the most crucial substances for life. In order to maintain their public health, each and every country has defined standards of drinking water quality, beyond which the water is considered harmful for human health. The current study compares physical, chemical, and biological standards of drinking water quality for the USA, EU, Japan, India, and Bangladesh, considering 4 physical parameters (namely, color, odor, taste, and turbidity), 35 chemical parameters (such as Calcium (Ca), Magnesium (Mg), Phosphate (PO43-), Sodium (Na), Phenolic compounds, Nitrite (NO2-), Arsenic (As), Aluminum (Al), etc.) and 2 biological parameters (i.e., Coliform (Fecal) and Coliform (Total)). The data has been collected from several secondary sources and since processes of data collection for water quality differ from one another, this aspect has been ignored. No variation has been found in biological water quality standards along with physical quality standards of the considered regions. In order to find out the differences in chemical parameters, standard ANOVA and pair-wise F-test have been conducted. There was no disparity among chemical parameters in ANOVA test. Moreover, thanks to the few excessive values of the standards (as in case of Bangladesh), the COD value is 4 mg/L, whereas in other countries this parameter is much less. However, the chemical parameters of water quality standards in Bangladesh vary significantly from other countries. Besides, there has been no variation among the standards of other countries, even though they are located in different continents. Most interestingly, despite being neighbors, Bangladesh and India differ significantly in this regard.
Mostrar más [+] Menos [-]La normalisation en qualite de l' air: la situation en France.
1992
Mienville P.
La surveillance de la qualite de l' air en Republique Federale d' Allemagne.
1987
Lahmann E.
Water quality standards and properties of bottling and mineral waters
2001
Stojiljkovic, D. (Poljoprivredni fakultet, Novi Sad (Yugoslavia). Institut za uredjenje voda)
Water quality is a main precondition for use in water supply and bottling. In this paper, a review of Yugoslavian standard referring to maximum allowed concentration of some components, as well as a review of some components contents in prohibited concentrations in Yugoslav and foreign bottling drinking and mineral waters are presented.
Mostrar más [+] Menos [-]Prioritising chemicals used in personal care products in China for environmental risk assessment: Application of the RAIDAR model
2012
Gouin, Todd | van Egmond, Roger | Price, Oliver R. | Hodges, Juliet E.N.
China represents a significant market for the sale of personal care products (PCPs). Given the continuous emission of hundreds of chemicals used in PCPs to waste water and the aquatic environment after regular use, methods for prioritising the environmental risk assessment for China are needed. In an effort to assess the prioritisation of chemicals used in PCPs in China, we have identified the chemical ingredients used in 2500 PCPs released to the Chinese market in 2009, and estimated the annual emission of these chemicals. The physical-chemical property data for these substances have been estimated and used as model inputs in the RAIDAR model. In general, the RAIDAR model provides an overall assessment of the multimedia fate of chemicals, and provides a holistic approach for prioritising chemical ingredients. The prioritisation exercise conducted in this study is shown to be strongly influenced by loss processes, such as the removal efficiencies of WWT plants and biotransformation.
Mostrar más [+] Menos [-]Associations between standardized school performance tests and mixtures of Pb, Zn, Cd, Ni, Mn, Cu, Cr, Co, and V in community soils of New Orleans
2012
Zahran, Sammy | Mielke, Howard W. | Weiler, Stephan | Hempel, Lynn | Berry, Kenneth J. | Gonzales, Christopher R.
In New Orleans a strong inverse association was previously identified between community soil lead and 4th grade school performance. This study extends the association to zinc, cadmium, nickel, manganese, copper, chromium, cobalt, and vanadium in community soil and their comparative effects on 4th grade school performance. Adjusting for poverty, food security, racial composition, and teacher-student ratios, regression results show that soil metals variously reduce and compress student scores. Soil metals account for 22%–24% while food insecurity accounts for 29%–37% of variation in school performance. The impact on grade point averages were Ni > Co > Mn > Cu ∼Cr ∼ Cd > Zn > Pb, but metals are mixtures in soils. The quantities of soil metal mixtures vary widely across the city with the largest totals in the inner city and smallest totals in the outer city. School grade point averages are lowest where the soil metal mixtures and food insecurity are highest.
Mostrar más [+] Menos [-]Concentrations and assessment of exposure to siloxanes and synthetic musks in personal care products from China
2011
Lu, Yan | Yuan, Tao | Wang, Wenhua | Kannan, Kurunthachalam
We investigated the concentrations and profiles of 15 siloxanes (four cyclic siloxanes, D₄–D₇; 11 linear siloxanes, L₄–L₁₄), four synthetic musks (two polycyclic musks, HHCB and AHTN; two nitro musks, MX and MK), and HHCB-lactone, in 158 personal care products marketed in China. Siloxanes were detected in 88% of the samples analyzed, at concentrations as high as 52.6 mg g⁻¹; Linear siloxanes were the predominant compounds. Among synthetic musks, more than 80% of the samples contained at least one of these compounds, and their total concentrations were as high as 1.02 mg g⁻¹. HHCB was the predominant musk in all of the samples analyzed, on average, accounting for 52% of the total musk concentrations. Based on the median concentrations of siloxanes and musks and the average daily usage amounts of consumer products, dermal exposure rates in adults were calculated to be 3.69 and 3.38 mg d⁻¹ for siloxanes and musks, respectively.
Mostrar más [+] Menos [-]Effect of water treatment residuals on soil phosphorus, copper and aluminium availability and toxicity
2010
Lombi, E. | Stevens, D.P. | McLaughlin, M.J.
Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil.
Mostrar más [+] Menos [-]A conceptual framework: Redefining forest soil's critical acid loads under a changing climate
2010
McNulty, Steven G. | Boggs, Johnny L.
Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it is believed to potentially impair forest health. The excess over the critical soil acid load is termed the exceedance, and the larger the exceedance, the greater the risk of ecosystem damage. This definition of critical soil acid load applies to exposure of the soil to a single, long-term pollutant (i.e., acidic deposition). However, ecosystems can be simultaneously under multiple ecosystem stresses and a single critical soil acid load level may not accurately reflect ecosystem health risk when subjected to multiple, episodic environmental stress. For example, the Appalachian Mountains of western North Carolina receive some of the highest rates of acidic deposition in the eastern United States, but these levels are considered to be below the critical acid load (CAL) that would cause forest damage. However, the area experienced a moderate three-year drought from 1999 to 2002, and in 2001 red spruce (Picea rubens Sarg.) trees in the area began to die in large numbers. The initial survey indicated that the affected trees were killed by the southern pine beetle (Dendroctonus frontalis Zimm.). This insect is not normally successful at colonizing these tree species because the trees produce large amounts of oleoresin that exclude the boring beetles. Subsequent investigations revealed that long-term acid deposition may have altered red spruce forest structure and function. There is some evidence that elevated acid deposition (particularly nitrogen) reduced tree water uptake potential, oleoresin production, and caused the trees to become more susceptible to insect colonization during the drought period. While the ecosystem was not in exceedance of the CAL, long-term nitrogen deposition pre-disposed the forest to other ecological stress. In combination, insects, drought, and nitrogen ultimately combined to cause the observed forest mortality. If any one of these factors were not present, the trees would likely not have died. This paper presents a conceptual framework of the ecosystem consequences of these interactions as well as limited plot level data to support this concept. Future assessments of the use of CAL studies need to account for multiple stress impacts to better understand ecosystem response.
Mostrar más [+] Menos [-]Management-oriented sensitivity analysis for pesticide transport in watershed-scale water quality modeling using SWAT
2009
Luo, Yuzhou | Zhang, Minghua
The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. Selected structural BMPs are recommended for reducing loads of OP pesticides.
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