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Exposure index of methyl isocyanate (MIC) gas disaster and a comprehensive spectrum of cytogenetic analysis after 30 years
2019
Ganguly, Bani Bandana
Severity of clinical expression and high mortality could not facilitate establishing exposure index/association following MIC disaster in Bhopal. Mortality-based exposure stratification was critiqued by the International Medical Commission on Bhopal (IMCB). IMCB stratified exposure considering distance as surrogate at 2 km intervals after 10 years. The first follow-up cytogenetic screening of the pre-screened survivors after 30 years has demonstrated chromosome abnormalities (CA). Exposure stratification was attempted considering cytogenetic screening conducted during 1986–1988. Elevation of CA appeared proportional to exposure status and authenticated the initial mortality-based stratification. The one-on-one comparison of the previous and present cytogenetics has described the individual response to MIC exposure over 30 years. Chi-square test has been carried out for checking the cytogenetic changes at the individual level statistically, which revealed that differences of chromosomal aberrations collected immediately post-disaster and 30 years later are nonsignificant. The prominence of interindividual variation was noticed in general. The impact of overall exposure was higher in males. Constitutional abnormalities in 8.5% of the study population, including translocation, inversion, deletion, fragile sites, etc., necessitate screening of blood-linked members. The incidence of acrocentric association was prominent in the study population. Normal karyotype in children born to severely exposed parents with congenital anomalies indicates necessity of molecular karyotyping and/or screening of mutations. The study highlights follow-up of the health of the index cases at shorter (3–6 months) intervals. This comprehensive spectrum of cytogenetic report highlights immediate post-disaster chromosomal aberrations, the changes that occurred over 30 years in conjunction with other environmental factors at the individual level, constitutive genomic aberrations, polymorphic variations, and chromosomal patterns in congenitally malformed children of the survivors, which collectively indicate the possibility of acquisition/persistence of stable aberrations in MIC-exposed lymphocytes through interaction with environmental/biological confounders.
Afficher plus [+] Moins [-]Application of Natural Organic Residues as Adsorbents to Remove Lead from Waters
2019
Oliveira, Luciana C. | Botero, Wander G. | Farias, Tamyris S. | Santos, Josué C. C. | Gabriel, Gabriele V. M. | Goveia, Danielle | Cacuro, Thiago A. | Waldman, Walter R.
The contamination of the environment by potentially toxic metals is highlighted by possible impacts of their high availability. Thus, the development of alternative absorbents that can be used in the remediation of contaminated areas, systems that are able to interact with these metals and affect their disposal, transportation, and bioavailability, is of great interest. Natural organic residue (NOR), often discarded as waste, is a promising alternative because it is capable of affecting the bioavailability of potentially toxic metals in the environment. This study assessed the interaction between NOR and NOR ashes (inorganic constituents) and lead ion (Pb²⁺), and its potential of adsorption, in order to analyze their use in contaminated areas. Two different NOR were evaluated and its structural characteristics presented differences in their organic material content and in its complexing capacity. NOR2 presented better capacity of complexing and adsorption of Pb²⁺ ions, performance that must be associated to the higher amount of organic matter present in the soil of this residue. In addition, the adsorption at pH 7.0 occurred through specific interactions with certain functional groups on the surface of NOR and NOR ashes. Besides that, the retention capacity of the Pb²⁺ ions was concentration dependent, in which the highest amount of mass will be the adsorbent retention. In light of this, the results obtained in this work highlight the importance of natural organic residues as a natural adsorbent material to lead removal.
Afficher plus [+] Moins [-]Consumers’ knowledge, attitude and behavioural patterns towards the liquid wastes (cooking oil) in Istanbul, Turkey
2019
Gurbuz, Ismail Bulent | Ozkan, Gulay
This study was carried out to reveal the people’s knowledge level about the harmful effects of waste oils, especially waste cooking oil, on the environment. It also aims to understand the attitude and behavioural patterns related to the safe disposal of them. Istanbul is chosen because it represents the entire country with its diverse socio-demographic and socio-cultural structure. A total of 408 respondents were randomly chosen and interviewed in the designated regions. The research data were obtained by using a structured survey consisting demographic and Likert scale questions. SPSS 23.0 statistical software was used to analyse the survey data. Results suggest that despite the high educational level, participants did not know that household liquid waste has a negative impact on the environment. They disagreed on the statement that liquid waste can damage water resources. Public spots, and formal and informal education were not found effective and failed to make the desired impact. Majority of participants did not know their duties in the disposal of waste. They also did not know where the liquid waste collection units were and what projects were being implemented in their neighbourhood. Fewer participants were concerned at what point and how the hazardous liquid wastes collected by municipalities were disposed of after leaving their habitat and whether these methods were reliable or acceptable. This research concludes that user behaviour was disappointing in cooking oil usage and waste oil disposal. The collection of waste cooking oils remains far below the developed countries.
Afficher plus [+] Moins [-]A dualistic water cycle system dynamic model for sustainable water resource management through progressive operational scenario analysis
2019
Peng, Jiayu | Lu, Shaoyong | Cao, Yimei | Wang, Xing | Hu, Xiaozhen | Wang, Minghao | Zheng, Binghui
A reliable system simulation of the reciprocal mechanism between water resource utilization and dualistic water cycle is essential to the basin water resource sustainability management. In this study, a system dynamic model was built to simulate the water cycle change and lake water environmental pressure under the influence of water resources utilization, and the procedure of a progressive operational scenario analysis of how to relieve water environment pressure was illustrated. Dianchi Lake, which is the sixth largest and the most severely polluted freshwater lake in China, was employed as a case study to demonstrate the applicability of the model. The change of runoff components and pollution load of total nitrogen from 2000 to 2030 were discussed. Also, the sustainable water resource management was ultimately realized in the planning period through three progressive levels of water resource regulation scenarios. Compared with business-as-usual scenario, the TN pollution load into lake and total water demand decrease by 27.1 and 27.3%, and the domestic water use, industry water use, tertiary industry water use, and irrigation decrease 9.0, 16.8, 29.5, and 30% in the scenario 3.
Afficher plus [+] Moins [-]The relief effects of organic acids on Scirpus triqueter L. under pyrene–lead stress
2019
Zhang, Xinying | Chen, Jing | Liu, Xiaoyan | Chen, Xueping | Liu, Lu | Niu, Yinghu | Wang, Rui
During phytoremediation of polycyclic aromatic hydrocarbons (PAHs) and heavy metals, the phytoremediation plants are often stressed by pollutants, which would reduce the efficiency of phytoremediation. The addition of organic acids from root exudates could alleviate the stress. In this study, three organic acids (citric acid, succinic acid, glutaric acid) were added to investigate the effects of organic acids on the stress response of Scirpus triqueter L. at two pyrene–lead concentrations. The activities of reactive oxygen species, malondialdehyde, plasma membrane H⁺-ATPase, and vacuolar H⁺-ATPase and PPase activity, as well as the activities of antioxidant enzymes (SOD, POD, and CAT) in Scirpus triqueter L. were determined. The addition of organic acids could effectively reduce the activities of reactive oxygen species, malondialdehyde, plasma membrane H⁺-ATPase, and vacuolar H⁺-ATPase and PPase activities. Under higher pollution, the damage of plant plasma membrane is more serious, but the addition of citric acid can alleviate this situation and even more effective than the relief under low pollution. The effect of citric acid was more significant than that of succinic acid and glutaric acid. These results demonstrated that organic acids could attenuate the stress of pyrene and lead to Scirpus triqueter L.
Afficher plus [+] Moins [-]Dewaterability enhancement and heavy metals immobilization by pig manure biochar addition during hydrothermal treatment of sewage sludge
2019
Xie, Shengyu | Yu, Guangwei | Li, Chunxing | You, Futian | Li, Jie | Tian, Renqiang | Wang, Gang | Wang, Yin
Hydrothermal treatment (HTT) of sewage sludge (SS) with pig manure biochar (PMB) addition at 160–200 °C was conducted in this study. The effects of PMB addition on the dewaterability of SS and the speciation evolution, leaching toxicity, and potential ecological risk of heavy metals were investigated. The results showed that the solid contents of the filter cakes after adding PMB increased from 20.24%, 24.03%, and 28.69% to 21.57%, 27.69%, and 32.91% at 160, 180, and 200 °C, respectively, compared with traditional HTT of SS. Furthermore, PMB could reduce the bioavailable fractions of Cr, Ni, As, and Cd in the filter cakes obtained at 160 and 180 °C compared with the theoretical value. The leaching toxicity of heavy metals in the filter cakes after adding PMB decreased significantly at 160 and 180 °C and the potential ecological risk index (RI) declined from 62.13 and 44.83 to 55.93 and 42.11, respectively. The obtained filter cake had low potential ecological risk when used in the environment. The mechanisms on the improvement of the dewaterability and heavy metals immobilization were related that PMB acted as the skeleton builder providing the outflow path for free water and implanting heavy metals into SS structure. And the optimal results were obtained at 180 °C during HTT of SS with PMB addition. This work provides a novel and effective method for the treatment of SS.
Afficher plus [+] Moins [-]Identification of 3-(trifluoromethyl)phenol as the malodorous compound in a pollution incident in the water supply in Catalonia (N.E. Spain)
2019
Quintana, Jordi | Hernández, Alejandra | Ventura, Francesc | Devesa, Ricard | Boleda, Maria Rosa
A study of organic compounds that caused a serious taste and odor episode of water supply in two residential areas in Catalonia (N.E. Spain) was carried out. Sweet and paint/solvent odor were the main descriptors used by consumers. Some cases of sickness and nausea were also associated with drinking water consumption by the consumers. Closed-loop stripping analysis (CLSA) combined with sensory gas chromatography and gas chromatography mass spectrometry detection were used to study the problem. As a result, 3-(trifluoromethyl)phenol (CAS number 98-17-9) was for the first time identified as a responsible of an odor incident in drinking water. Concentration levels of this compound were up to 17,000 ng/L in groundwater and up to 600 ng/L in distributed water. Odor threshold in water for 3-(trifluoromethyl)phenol was determined as 13 ng/L (45 °C).
Afficher plus [+] Moins [-]Co-benefits analysis of energy cascade utilization in an industrial park in China
2019
Ma, Yilan | Wang, Shanshan | Wang, Ke | Liu, Lei | Zhang, Ruiqin
As an important role in economic development in China, industrial parks have consumed plenty of energy, while emitting enormous air pollutants and discharging large quantities of waste heat. Energy cascade utilization is an effective way to improve the energy efficiency of industrial parks. The objective of this study was to assess the co-benefits of energy cascade utilization, including the energy savings potential, reduction potential of air pollutants, and air quality improvements, in an industrial park in China. Through an energy flow analysis of steam at different pressures and residual gas among various enterprises, this study identified the existing energy cascade utilization network in a baseline scenario and proposed an enhanced scenario. To evaluate the co-benefits of these two scenarios, the CALPUFF model was used to integrate energy savings and air pollutant mitigation for the park in 2017. The results show that energy cascade utilization can result in considerable co-benefits related to energy conservation, air pollutant emission reductions, and air quality improvements. In the enhanced scenario, the total energy savings potential is 11,425 TJ, with emission reductions of 859 tons of SO₂ and 910 tons of NOₓ. Based on the CALPUFF simulations of SO₂ and NOₓ diffusion in the four seasons, the concentrations of SO₂ and NOₓ in the study area considerably decreased in the enhanced scenario compared with those in the baseline scenario. This study demonstrates that the park should focus on the cascade utilization of waste heat and residual gas to improve the energy utilization efficiency and reduce atmospheric pollutant emissions.
Afficher plus [+] Moins [-]Occurrences and patterns of residual organochlorine pesticides (OCPs) in cultured Chinese mitten crab (Eriocheir sinensis) in China: concentrations, sources, and a human health risk assessment
2019
Song, Chao | Zhang, Cong | Zhang, Jingwei | Zhang, Xiaowei
Seventy Chinese mitten crab samples, encompassing a total of 2100 individuals, were collected from the main production areas in China. The objective was to assess the occurrences and patterns of 23 selected organochlorine pesticides (OCPs) in the edible tissues and assess the associated dietary risk. Concentrations of total residual OCPs in the mitten crabs ranged from 0.72 to 51.51 μg kg⁻¹, which was comparable to other global aquatic species. Dichlorodiphenyl trichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) were the two main contributors of total OCPs, with the detected values ranging from 0.14 to 30.89 μg kg⁻¹ and 0.23 to 4.04 μg kg⁻¹, respectively. Source analysis indicated the coexistence of both residual and recent DDT inputs, while there was no indication of HCH usage in the main production area of mitten crab. In terms of dietary risk, at least eight individual mitten crabs per day are permissible for consumption by local residents, indicating low risk from consumption. The results presented herein should guide the production and consumption of mitten crab, as well as promote the sustainable development of aquaculture in China.
Afficher plus [+] Moins [-]Increasingly Distant from Eden—a Look at the Soils of Protected Areas Using Ecotoxicological Tests and Chemical Analysis
2019
Honscha, Laiz Coutelle | de Moura, Renata Rodrigues | Baisch, Paulo Roberto Martins | Da Silva Júnior, Flavio Manoel Rodrigues
On the basis of the assumption that legally protected areas are created to maintain environmental quality that, in turn, is indispensable for quality of life, this study aims to evaluate the soil conditions in protected areas that are located near urban regions by using ecotoxicological assays and chemical analysis. The study was carried out using surface soil samples collected from seven protected areas in southern Brazil. For the protected area to be considered “clean,” the results of the ecotoxicological tests should be within the criteria accepted for negative control according to standardized protocols, and the concentration of chemical elements should be below the maximum levels allowed by Brazilian law. On the basis of the criteria adopted for ecotoxicological assays and chemical analysis, soil from only two of the seven protected areas (28.6%) met the criteria for being considered “clean.” This probably reflects the influence of anthropogenic activities within the protected areas, demonstrating drawbacks of delimitation and management. The strategy used in this study could be used to assess the anthropogenic impact on protected areas in other parts of the world.
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