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Measuring air particulate matter in large urban areas for health effect assessment
2007
Almeida, S. M. | Farinha, M. M. | Ventura, M. G. | Pio, C. A. | Freitas, M. C. | Reis, M. A. | Trancoso, M. A.
This study deals with Particle Matter (PM) levels in the metropolitan area of Lisbon and shows that EU directive is exceeded in a systematic way, mainly due to the inner city traffic. Results show that it is important to develop an epidemiological study in Lisbon to find a possible association between PM levels, sources and morbidity. Some important issues related with a monitor's representation of regional, sub-regional, and local air pollution exposures to the population in the metropolitan area are highlighted. PM₂.₅ and PM₁₀ total mass concentration measured in several places located in both centre of Lisbon and the outskirts are quite well correlated, mainly considering that two measuring methodologies (automatic and gravimetric) were used and areas with different classifications (urban and suburban) were analysed. However, the results imply that a source-oriented evaluation of PM health effects needs to take into account the uncertainty associated with spatial representativity of the species measured at a single sampling station. Temporal correlation across sampling stations, within relatively short separation distances, varied considerably for some important elements (Zn, Sb, Cu, As and Br), indicating that the precision of population exposure estimates for specific elements can vary depending on the species.
Показать больше [+] Меньше [-]PM₁₀-bound Polycyclic Aromatic Hydrocarbons (PAHs) and Cancer Risk Estimation in the Atmosphere Surrounding an Industrial Area of Shanghai, China
2007
Cheng Jinping. | Yuan, Tao | Wu, Qian | Zhao, Wenchang | Xie, Haiying | Ma, Yingge | Ma, Jing | Wang, Wenhua
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in the urban atmosphere. In particular, atmospheric pollution has increasingly become severe in China due to its rapid urbanization and industrialization. In recent years, a few studies have presented information about POPs (such as PAHs, PCBs, OCPs) in aerosols at a molecular level in a limited number of cities such as Beijing, Qingdao and Guangzhou, as well as Hong Kong. Whereas, these cities are located in northern and southern China, respectively, where characteristics of atmospheric pollution might be different from those in the eastern cities, such as Shanghai. Atmospheric particle pollution is a persistent problem in Shanghai, a typical metropolis of China, which has several huge industrial regions. In order to gain a comprehensive understanding of the present state, properties and sources of PAHs pollution in Shanghai, PM₁₀ samples were collected at Coal-Fired Power Plant (CFP), Chlor-Alkali Chemical factory (CAC) and Coking and Chemical factory (CCF) in an industrial area, during the period, November 2004-September 2005. The concentrations of 16 PAHs were analyzed using the HPLC with UV visible detector. The results showed that the mean value of total PAHs in the industrial area was 64.85 ng m-³; 3-ring PAHs were found at low levels, while 4-, 5- and 6-ring PAHs were found at high levels. The levels of BaP were 3.07 and 7.16 ng m-³ at Chlor-Alkali Chemistry Factory and Coking and Chemistry Factory sites, respectively. PAHs levels exhibited distinct seasonal variation, with the highest level in autumn and the lowest in summer. The major source of PAHs at the industrial area was fossil fuel combustion, coal-burning, industrial furnaces including others. There was a very significant correlation of PAHs levels between CCF and CAC (R ² = 0.91). The average concentration of BaP in the industrial area during the sampling period was 5.95 ng m-³. It could be concluded the local population appears to be exposed to significantly high cancer risk (exceeding 2 ng m-³ in autumn and winter) as compared to the population of other areas.
Показать больше [+] Меньше [-]Phenylalanine Ammonia-Lyase and Phenolic Compounds in Chamomile Tolerance to Cadmium and Copper Excess
2007
Kováčik, Jozef | Bačkor, Martin
Phenylalanine ammonia-lyase activity (PAL, EC 4.3.1.5), total phenolics, soluble proteins, malondialdehyde and metals accumulation in four-week old chamomile (Matricaria chamomilla) plants cultivated in nutrient solution and exposed to low (3 μM) and high (60 and 120 μM) levels of cadmium (Cd) or copper (Cu) for 7 days were studied. High Cd concentrations had a stimulatory effect on PAL activity and soluble phenolics accumulation while high Cu doses decreased soluble proteins in the leaf rosettes. In the roots, extreme stimulatory effects of 60 and 120 μM Cu were observed on PAL activity, phenolics and malondialdehyde accumulation, while protein content was reduced by these Cu doses. Cd accumulation was higher in the leaf rosettes compared to copper, but the opposite was recorded in the roots. Taken together, the stimulatory effect of Cu on phenolic metabolism was recorded, even though high malondialdehyde accumulation may be an indication that phenolics was not sufficient to counteract reactive oxygen species formation thus leading to damage of membrane integrity. In comparison to Cd, Cu had more noticeable effect on the parameters studied to support its strong redox-active properties. These facts in correlation to antioxidative properties of phenolic metabolites are also discussed.
Показать больше [+] Меньше [-]The OECD Validation Program of the H295R Steroidogenesis Assay for the Identification of In Vitro Inhibitors and Inducers of Testosterone and Estradiol Production. Phase 2: Inter-Laboratory Pre-Validation Studies (8 pp)
2007
Hecker, Markus | Hollert, Henner | Cooper, R. (Ralph) | Vinggaard, Anne-Marie | Akahori, Yumi | Murphy, Margaret | Nellemann, Christine | Higley, Eric | Newsted, John | Wu, Rudolph | Lam, Paul | Laskey, John | Buckalew, Angela | Grund, Stefanie | Nakai, Makoto | Timm, Gary | Giesy, John
BACKGROUND: Goals and Scope. In response to concerns that have been raised about chemical substances that may alter the function of endocrine systems and result in adverse effects on human health, an OECD initiative was undertaken to develop and validate in vitro and in vivo assays to identify chemicals that may interfere with endocrine systems of vertebrates. Here we report on studies that were conducted to develop and standardize a cell-based screening assay using the H295R cell line to prioritize chemicals that may act on steroidogenic processes in humans and wildlife. These studies are currently ongoing as part of the 'Special Activity on the Testing and Assessment of Endocrine Disruptors' within the OECD Test Guidelines Program to review, develop, standardize, and validate a number of in vitro and in vivo toxicological assays for testing and assessment of chemicals concerning their potential to interact with the endocrine system of vertebrates. -: Study Design. Six laboratories from five countries participated in the pre-validation studies. Each laboratory tested the effects of three model chemicals on the production of testosterone (T) and estradiol (E2) using the H295R Steroidogenesis Assay. Chemicals tested were well described inducers or inhibitors of steroidogenic pathways (forskolin, prochloraz and fadrozole). All experiments were conducted in 24 well plates following standard protocols. Six different doses per compound were analyzed in triplicate per plate. A quality control (QC) plate was run in conjunction with the chemical exposure plate to account for inter-assay variation. Each chemical exposure was conducted two or three times. RESULTS: All laboratories successfully detected increases and/or decreases in hormone production by H295R cells after exposure to the different model compounds and there was good agreement in the pattern of response for all groups. Forskolin increased both T and E2 while fadrozole and prochloraz decreased production of both hormones. All chemicals affected hormone production in a dose-response manner with the exception of fadrozole which caused maximum inhibition of E2 at the two least concentrations tested. Some inter-laboratory differences were noted in the alteration of hormone production measured in chemically exposed cells. However, with the exception of the production of T measured at one laboratory in cells exposed to forskolin, the EC50s calculated were comparable (coefficients of variation 34-49%) for all hormones. DISCUSSION: and Perspectives. The results indicated that the H295R Steroidogenesis Assay protocol was robust, transferable and reproducible across all laboratories. However, in several instances that were primarily related to one laboratory there were unexplained minor uncertainties related to the inter-laboratory hormone production variation. Based on the findings from this Phase 2 pre-validation study, the H295R Steroidogenesis Assay protocol is currently being refined. The next phase of the OECD validation program will test the refined protocol across the same group of laboratories using an extended set of chemicals (~30) that will include positive and negative chemical controls as well as a broad spectrum of different potential inducers and inhibitors of steroidogenic pathways.
Показать больше [+] Меньше [-]Fragrances in the Environment: Pleasant odours for nature? (9 pp)
2007
Klaschka, Ursula | Kolossa-Gehring, Marike
GOAL, SCOPE AND BACKGROUND: Fragrance preparations or perfumes are used in an increasing variety of applications, as for example washing, cleansing, personal care products, consumer goods or in applications to modify indoor air. However, up to now, little is known to the general or scientific public about their chemical identity and the use pattern of single substances, not even for high production volume chemicals. Some toxicological data are published for a comparatively small number of substances with a focus on sensitisation and dermal effects, while other effects are neglected. Information on ecotoxicity and environmental fate are rare, especially for long-term exposure. Data for a detailed hazard and risk analysis are available in exceptional cases only. According to the current legal situation, fragrance industry is self-regulated, which means that pre-market risk evaluation is not required for most fragrances. Odour and the ability to smell play a major role for wildlife for all taxonomic groups. Reproductive and social behaviour, defence, communication and orientation depend on volatile compounds which can be identical to those used in fragrance preparations. Our interdisciplinary approach leads to the question of whether and, if so, to what extent anthropogenic fragrances may influence life and reproduction of organisms in the environment. MAIN FEATURES: Information from literature on use, exposure and biological effects was combined to analyse the state of knowledge. Following an overview of the amounts of fragrances used in different consumer products and their release into the environment, the roles of odours in nature are shown for a selection of compounds. Existing regulation was analysed to describe the data basis for environmental risk evaluation. Finally, recommendations for further action are derived from these findings. RESULTS: Three main results were elaborated: First, fragrance substances are continuously discharged in large amounts into the environment, especially via the waste water. Second, there are some indications of negative effects on human health or the environment, although the data basis is very thin due to the self regulation of the fragrance industry and the regulatory situation of fragrance substances. Third, many odoriferous substances used by man are identical to those which are signal substances of environmental organisms at very low concentrations, thus giving rise to specific mode of actions in the ecosystem. RECOMMENDATION: For the adequate risk assessments of fragrances, test results on their unspecific as well as their specific effects as signal substances are needed. This would imply prioritisation methods and development of useful test methods for specific endpoints for appropriate risk assessments. Before a comprehensive testing and evaluation of results has been finished, a minimization of exposure should be envisaged. Eco-labelling of products containing acceptable fragrance ingredients could be a first step and provide consumers with the respective information. Transparency concerning the fragrance ingredients used and their biological potency will help to build up confidence between producers and consumers. CONCLUSIONS AND PERSPECTIVES: The interdisciplinary approach, bringing together chemical, biological, toxicological and ecotoxicological data with information provided by manufacturers and with legal and consumer aspects, offers new insights into the field of fragrance substances used in consumer products. The amounts and application fields of fragrance substances increases while fate and effects in the environment are hardly known. The current legal situation is not suited to elucidate the effects of fragrances on human health and the environment sufficiently, especially as it was shown that fragrances may play a considerable role in the ecosystem on the behaviour of organisms. According to the precautionary principle, the lack of knowledge should best be tackled by reducing exposure, especially for compounds such as fragrance substances where no ethical reasons object a substitution by less hazardous chemicals.
Показать больше [+] Меньше [-]Organic Contaminants from Sewage Sludge Applied to Agricultural Soils. False Alarm Regarding Possible Problems for Food Safety? (8 pp)
2007
Laturnus, Frank | von Arnold, Karin | Grøn, Christian
GOAL, SCOPE AND BACKGROUND: Sewage sludge produced in wastewater treatment contains large amounts of organic matter and nutrients and could, therefore, be suitable as fertiliser. However, with the sludge, besides heavy metals and pathogenic bacteria, a variety of organic contaminants can be added to agricultural fields. Whether the organic contaminants from the sludge can have adverse effects on human health and wildlife if these compounds enter the food chain or groundwater still remains a point of controversial discussion. MAIN FEATURES: This paper presents an overview on the present situation in Europe and a summary of some recent results on the possible uptake of organic contaminants by crops after addition to agricultural fields by sewage sludge. RESULTS: Greenhouse experiments and field trials were performed to study the degradation and uptake of organic micro-contaminants in sludge-amended agricultural soil in crops, such as barley and carrots grown in agricultural soil amended with anaerobically-treated sewage sludge from a wastewater treatment plant, but studies hitherto have revealed no immediate risks. Common sludge contaminants such as linear alkylbenzene sulphonates (LAS), nonylphenol ethoxylates (NPE), polycyclic aromatic hydrocarbons (PAH), bis(diethylhexyl) phthalate (DEHP), showed neither accumulation in soil nor uptake in plants. DISCUSSION: It is assumed that the annual amount of sewage sludge produced in Europe will increase in the future, mainly due to larger amounts of high quality drinking water needed by an increasing population and due to increasing demands for cleaner sewage water. Application of sewage sludge to agricultural soils is sustainable and economical due to nutrient cycling and disposal of sewage sludge. However, this solution also involves risks with respect to the occurrence of organic contaminants and other potentially harmful contents such as pathogens and heavy metals present in the sludge. There have been concerns that organic contaminants may accumulate in the soil, be taken up by plants and thereby transferred to humans via the food chain. Results obtained so far revealed, however, no immediate risk of accumulation of common organic sludge contaminants in soil or uptake in plants when applying sewage sludge to agricultural soil. With very high dosages of sewage sludge, there may be a risk for accumulation of very apolar contaminants, such as DEHP, to the soil. CONCLUSIONS: Any conclusions on the safe use of sewage sludge in agriculture have to be drawn carefully, as the studies performed until now have been limited. Further studies are required, and before final statements can be drawn, it is imminent to study a larger variety of common crops and the effect sewage sludge application may have on a possible accumulation of organic contaminants in the crops. Furthermore, a larger variety of organic contaminants need to be studied and special focus should be given to contaminants newly introduced into the environment. Besides investigating possible plant uptake of organic contaminants, the fate of these compounds in soil after sludge application need to be monitored too. Here, special attention has to be given to studies on degradation and the formation of degradation products, to weathering and to leaching effects on groundwater, to the application of different crops on the same field (crop rotation), to the use of full-width tillage and strip tillage, and to long term application of sewage sludge on the soil. RECOMMENDATIONS AND PERSPECTIVE: There are environmental, political as well as economical incentives to increase the agricultural application of sludge. However, such usage should be performed with care as there are also ways in which sludge fertilisation could harm the environment and human health. Recently, a new European COST Action (859) has been established covering the field of food safety and improved food quality. Part of the Action is dealing with the application of sewage sludge in agriculture. Before any political and economical measures can be taken, the pros and cons have to be sufficiently investigated on a scientific level first.
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