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211.
Environmental Science and Pollution Research - This study evaluated the nephroprotective effect of kaempferol against cadmium chloride (CdCl2) -induced nephropathy in rats. It also investigated if...  相似文献   
212.

Through administrative research and media records, this paper aims to examine and highlight the effects of the COVID-19 pandemic on Malaysian workers, property development, construction sites, and the national economy. The development of real estate and the construction industry can significantly impact socio-economic growth and infrastructure development. Adequate building and infrastructure construction can ensure national economic stability, job creation, community cohesion, and higher living standards. Since the COVID-19 pandemic began in 2019, many countries, including Malaysia, have reported an increased number of virus cases. According to the Ministry of Health, 9316 cases and 314 COVID-19 clusters were discovered in Malaysia, with a 38.55–48.06% prevalence for factories, a 12.55–15.29% prevalence for community spreading, an 8.6–11.56% prevalence for construction sites, a 5.53–7.96% prevalence for educational sites, and a 7.01% prevalence for shopping areas. Several governments-imposed lockdowns, movement, and proximity restrictions during the pandemic due to the high infection rates at property development sites. However, due to inactivity in various sectors such as the construction industry, these measures have significantly impacted the national economy. As a result, the pandemic has had an impact on workers, production costs, and project completion timelines, resulting in operational issues and policy concerns. Overall, the records reviewed revealed that the COVID-19 pandemic has significantly impacted real estate development, the housing market, and the construction industry. As a result, sustained and targeted policies are required to support Malaysia’s construction industry’s socio-economic growth and infrastructure development.

  相似文献   
213.
Environmental Science and Pollution Research - Exposure of geomaterials to acidic leachates may compromise their structure and functionality due to changes in physicochemical, mineralogical, and...  相似文献   
214.
Fromberg A  Cederberg T  Hilbert G  Büchert A 《Chemosphere》2000,40(9-11):1227-1232
The levels of toxaphene congeners, in addition to PCB congeners and organochlorine pesticides, were determined in various fish samples from different Danish waters. While PCB-153 and p,p'-DDE show different levels depending on the fishing area, with highest levels in fish from the Western Baltic Sea, toxaphene was detected in all the samples investigated at a more constant level. The distribution of the three toxaphene congeners Parlar #26, #50 and #62 depends on the fishing area, with the Western Baltic Sea being different from the other waters by having almost equal levels of toxaphene congeners #26 and #50.  相似文献   
215.
Toxicity potentials are standard values used in life cycle assessment (LCA) to enable a comparison of toxic impacts between substances. In most cases, toxicity potentials are calculated with multi-media fate models. Until now, unrealistic system settings were used for these calculations. The present paper outlines an improved model to calculate toxicity potentials: the global nested multi-media fate, exposure and effects model USES-LCA. It is based on the Uniform System for the Evaluation of Substances 2.0 (USES 2.0). USES-LCA was used to calculate for 181 substances toxicity potentials for the six impact categories freshwater aquatic ecotoxicity, marine aquatic ecotoxicity, freshwater sediment ecotoxicity, marine sediment ecotoxicity, terrestrial ecotoxicity and human toxicity, after initial emission to the compartments air, freshwater, seawater, industrial soil and agricultural soil, respectively. Differences of several orders of magnitude were found between the new toxicity potentials and those calculated previously.  相似文献   
216.
Kinyanjui T  Gitu PM  Kamau GN 《Chemosphere》2000,41(7):1071-1074
Thin layer chromatography (TLC) analysis revealed that destructive distillation of Juniperus procera tree gave ten major components, whereas Croton megalocarpus tree yielded five components. This was confirmed by gas chromatography (GC). The components were isolated by column chromatography and analysed using infrared, ultra-violet, visible and mass spectroscopy (MS) techniques. The whole extract was about 30.3% of the starting material (sawdust) and consisted of 77.5% water and 22.5% oily reddish-brown layer. The extracts had alcoholic and phenolic compounds together with acids. Cedrol, a tertiary tricyclic alcohol, was found to be in the greatest proportion in the oily layer. IR spectra with a peak beyond 3000 cm(-1), UV-VIS absorption maxima at 230 nm and mass spectra with m/e 204 suggested the presence of cedrene in the extract.  相似文献   
217.
This paper discusses the legal and scientific reasons for separating personal exposure to PM into ambient and nonambient components. It then demonstrates by several examples how well-established models and data typically obtained in exposure field studies can be used to estimate both individual and community average exposure to ambient-generated PM (ambient PM outdoors plus ambient PM that has infiltrated indoors), indoor-generated PM, and personal activity PM. Ambient concentrations are not highly correlated with personal exposure to nonambient PM or total PM but are highly correlated with personal exposure to ambient-generated PM. Therefore, ambient concentrations may be used in epidemiology as an appropriate surrogate for personal exposure to ambient-generated PM. Suggestions are offered as to how exposure to ambient-generated PM may be obtained and used in epidemiology and risk assessment.  相似文献   
218.
Monitoring and laboratory data play integral roles alongside fate and exposure models in comprehensive risk assessments. The principle in the European Union Technical Guidance Documents for risk assessment is that measured data may take precedence over model results but only after they are judged to be of adequate reliability and to be representative of the particular environmental compartments to which they are applied. In practice, laboratory and field data are used to provide parameters for the models, while monitoring data are used to validate the models' predictions. Thus, comprehensive risk assessments require the integration of laboratory and monitoring data with the model predictions. However, this interplay is often overlooked. Discrepancies between the results of models and monitoring should be investigated in terms of the representativeness of both. Certainly, in the context of the EU risk assessment of existing chemicals, the specific requirements for monitoring data have not been adequately addressed. The resources required for environmental monitoring, both in terms of manpower and equipment, can be very significant. The design of monitoring programmes to optimise the use of resources and the use of models as a cost-effective alternative are increasing in importance. Generic considerations and criteria for the design of new monitoring programmes to generate representative quality data for the aquatic compartment are outlined and the criteria for the use of existing data are discussed. In particular, there is a need to improve the accessibility to data sets, to standardise the data sets, to promote communication and harmonisation of programmes and to incorporate the flexibility to change monitoring protocols to amend the chemicals under investigation in line with changing needs and priorities.  相似文献   
219.
Ishii S  Hisamatsu Y  Inazu K  Kobayashi T  Aika K 《Chemosphere》2000,41(11):1809-1819
In order to clarify the contribution of nitrated products to the direct-mutagenic activity of products of the reactions of benzo[a]pyrene in NO2-air under various conditions, heterogeneous reactions of BaP deposited on filter in the air containing 10 ppm of NO2 have been conducted in dark or under photoirradiation. The reaction products have been analyzed by gas chromatography and mutagenicity of the products fractionated by preparative HPLC was assayed for Salmonella typhimurium strains TA98 and YG1024 in the absence of S9 mix. 3,6-dinitrobenzo[a]pyrene and 1,3-dinitrobenzo[a]pyrene, which are strong direct-acting mutagens, largely contributed to the total direct-acting mutagenicity of the dark reaction products in NO2-air. On the other hand, both the dark reaction in the presence of O3 and the photoreaction in NO2-air resulted in the formation of much smaller amounts of nitrobenzo[a]pyrenes than that observed in the dark reaction in the absence of O3. These results show that the contribution of other direct-acting mutagens to the total direct-acting mutagenicity of the products in these reactions should be considered. Benzo[a]pyrene lactones were identified in a highly mutagenic fraction of the products of the dark reaction in the presence of O3 and photoreaction and a nitrobenzo[a]pyrene lactone was also identified in a highly mutagenic fraction of the dark reaction products in the presence of O3. Nitrated oxygenated benzo[a]pyrene derivatives such as nitrobenzo[a]pyrene lactone were considered to largely contribute to direct-acting mutagenicity of the products of the dark reaction in the presence of O3 and photoreaction.  相似文献   
220.
The analysis of the horizons of 12 soil profiles confirm occasionally significant levels of Cd, Pb and Zn contamination in the areas surrounding two lead and zinc smelters in the North of France. A pedological approach enabled the original Cd, Pb and Zn content of the horizons to be estimated, based on physico-chemical characteristics of soil unaffected by contamination. The main contamination was found in the upper 20-30 cm. Traces of Cd and Zn contamination were found at a depth of around 2 m. The mobility of the metals may be classified in the following order: Cd>Pb> or =Zn. The concentration profile of a metal seems insufficient to evaluate its movement as the metal could have been leached beyond the contaminated horizons. The depth reached by the metals increases with their concentration in the surface horizon; a decrease in pH and an increase in sand content seem to facilitate their movement. The depth reached by Zn increases with the organic carbon content in the surface horizon. Earthworm galleries act as paths via which metals migrate downwards  相似文献   
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