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1.
During Balkan conflicts in 1994-1995, depleted uranium (DU) ordnance was employed and was left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Bosnia and Herzegovina, radiological survey of DU in biological and water samples were carried out over the period 12-24 October 2002. The uranium isotopic concentrations in biological samples collected in Bosnia and Herzegovina, mainly lichens, mosses and barks, were found to be in the range of 0.27-35.7 Bq kg(-1) for (238)U, 0.24-16.8 Bq kg(-1) for (234)U, and 0.02-1.11 Bq kg(-1) for (235)U, showing uranium levels to be higher than in the samples collected at the control site. Moreover, the (236)U in some of the samples was detectable. The isotopic ratios of (234)U/(238)U showed DU to be detectable in many biological samples at most sites examined, but in very low levels. The presence of DU in the biological samples was as a result of DU contamination in air. The uranium concentrations in water samples collected in Bosnia and Herzegovina were found to be in the range of 0.27-16.2 m Bq l(-1) for (238)U, 0.41-15.6 m Bq l(-1) for (234)U and 0.012-0.695 m Bq l(-1) for (235)U, and two water samples were observed to be DU positive; these values are much lower than those in mineral water found in central Italy and below the WHO guideline for public drinking water. From radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated sites in terms of possible DU contamination of water and/or plants.  相似文献   

2.
Vulnerabilities to floods in Thailand are changing as a result of many factors. Formal and informal institutions help shape exposure, sensitivity and capacities to respond of individuals, social groups and social-ecological systems. In this paper we draw on several case studies of flood events and flood-affected communities to first assess how current practices reflect various laws, procedures, programs and policies for managing floods and disasters and then explore the implications for dealing with additional challenges posed by climate change. Our analysis identifies several institutional traps which need to be overcome if vulnerability is to be reduced, namely capture of agendas by technical elites, single-level or centralized concentration of capacities, organizational fragmentation and overemphasis on reactive crisis management. Possible responses are to expand public participation in managing risks, build adaptive capacities at multiple levels and link them, integrate flood disaster management and climate change adaptation into development planning, prioritize risk reduction for socially vulnerable groups and strengthen links between knowledge and practice. Responses like these could help reduce vulnerabilities under current climate and flood regimes, while also improving capacities to handle the future which every way that unfolds.  相似文献   

3.
Samples of precipitation events (snow and rain) in Dalian, a typical coastal town in China, were analyzed for perfluorosulfonates (PFSAs) and perfluorocarboxylates (PFCAs) to investigate atmospheric contamination by these compounds. In the snow event on December 16, 2006, samples were collected from 21 different sites and in another 6 precipitation events, samples were collected from a single location. Four PFSAs (C4, C6, C8, C10) and seven PFCAs (C6–12) were analyzed. Among the homologues, perfluorooctane sulfonate (PFOS) concentrations were the highest with a geometric mean (GM) of 145 ng/L (n = 21) during the snow event on December 16, 2006, followed by perfluorooctanoate (PFOA) with a GM of 24.7 ng/L (n = 21). Concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and perfluoroheptanoate (PFHpA) were more than two orders of magnitude lower than that of PFOS. Other PFSAs and PFCAs were found to be below the limit of detection in all the samples. In other 6 precipitation events, PFSAs and PFCAs were detected approximately in the same order of magnitude in both snow and rain. The results indicate that wet deposition may be a potential transport mechanism of perfluorinated chemicals in the environment.  相似文献   

4.
Fate and transport of pathogens in lakes and reservoirs   总被引:3,自引:0,他引:3  
Outbreaks of water-borne disease via public water supplies continue to be reported in developed countries even though there is increased awareness of, and treatment for, pathogen contamination. Pathogen episodes in lakes and reservoirs are often associated with rain events, and the riverine inflow is considered to be major source of pathogens. Consequently, the behaviour of these inflows is of particular importance in determining pathogen transport and distribution. Inflows are controlled by their density relative to that of the lake, such that warm inflows will flow over the surface of the lake as a buoyant surface flow and cold, dense inflows will sink beneath the lake water where they will flow along the bathymetry towards the deepest point. The fate of pathogens is determined by loss processes including settling and inactivation by temperature, UV and grazing. The general trend is for the insertion timescale to be shortest, followed by sedimentation losses and temperature inactivity. The fate of Cryptosporidium due to UV light inactivation can occur at opposite ends of the scale, depending on the location of the oocysts in the water column and the extinction coefficient for UV light. For this reason, the extinction coefficient for UV light appears to be a vitally important parameter for determining the risk of Cryptosporidium contamination. For risk assessment of pathogens in supply reservoirs, it is important to understand the role of hydrodynamics in determining the timescale of transport to the off-take relative to the timescale of inactivation. The characteristics of the riverine intrusion must also be considered when designing a sampling program for pathogens. A risk management framework is presented that accounts for pathogen fate and transport for reservoirs.  相似文献   

5.
110mAg, as a radionuclide of corrosion products in water-cooled nuclear reactors, was detected in the liquid effluents of Guangdong Daya Bay Nuclear Power Station (GNPS) of Daya Bay under normal operation conditions. Experiments on a simulated terrestrial agricultural ecosystem were carried out using the pot experiment approach. The most common plants in Hong Kong and the South China vegetable gardens such as lettuce, Chinese spinach, kale, carrot, pepper, eggplant, bean, flowering cabbage, celery, European onion and cucumber were selected for (110m)Ag root and foliar uptake tests. The results show that carrot, kale and flowering cabbage have the greatest values of soil to plant transfer factor among the vegetables, while(110m)Ag can be transferred to Chinese spinach via foliar uptake. Flowering cabbage, the most popular leafy vegetable locally, could be used as a biomonitor for the radioisotope contamination in vegetables. Soil column and adsorption tests were also carried out to study the leaching ability and distribution coefficient (K(d)) of (110m)Ag in the soil. The results show that most of the radionuclide was adsorbed in the top 1 cm of soil regardless of the pH value. The K(d) was also determined.  相似文献   

6.
Both climate extremes and agricultural disasters have been reported to increase in recent decades; however, so far, we have little idea on the characteristics of agricultural disasters changes, as well as their meteorological and agronomic causes. Here, using the observed records on rice disasters at agro-meteorological stations across China and the meteorological indexes, we investigated the temporal and spatial changes of major rice disasters occurrence frequency and their relationships to climate change, climate extremes and agronomic practices from 1991 to 2009. We presented the temporal and spatial changes in occurrence frequency of major rice disasters, including droughts, floods, heat stress, chilling damage, insects and diseases, during the warmer period of 2000–2009, in comparison with the period of 1991–2000, based on both the observed records and the meteorological indexes. The results showed that changes in rice disasters could be largely ascribed to changes in climate extremes in recent decades. Floods, insects and diseases occurred more frequently at earlier growth stages; in contrast, chilling damage occurred more frequently at later growth stages in southwestern China during the period of 2000–2009, in comparison with the period of 1991–2000. Our findings highlighted the options should be taken timely and scientifically to reduce the disasters and to cope with ongoing climate change, based on the characteristics of agricultural disasters changes in recent decades.  相似文献   

7.
BackgroundAlthough antibiotic use during early life has been demonstrated to be related to the altered adipogenesis in later life, limited data are available for the effect of antibiotic exposure in school children on adiposity from various sources, including from the use or contaminated food or drinking water.ObjectiveTo explore the association between the internal exposure of antibiotics from various sources and adipogenesis in school children using the biomonitoring of urinary antibiotics.MethodsAfter 586 school children aged 8–11 years were selected from Shanghai in 2013, total urinary concentrations (free and conjugated) of 21 common antibiotics from six categories (macrolides, β-lactams, tetracyclines, fluoroquinolones, sulfonamides, and phenicols), including five human antibiotics (HAs), two antibiotics preferred as HA, four veterinary antibiotics (VAs), and ten antibiotics preferred as VA, were measured by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. Creatinine-corrected urinary concentrations of antibiotics were used to assess their exposure. Overweight or obesity was determined by the body mass index or waist circumference-based criteria deriving from national data.ResultsAll 21 antibiotics were found in urines with the overall detection frequency of 79.6%. The multinomial logistic regression analyses showed the significant associations of overweight and obesity with the exposure to VAs and antibiotics preferred as VA, but not with HAs or antibiotics preferred as HA. After adjusted for a number of obesity-relevant variables, the odds ratios (95% confidence interval) of BMI-based obesity risk of tertiles 2 and 3 of urinary concentrations relative to tertile 1 were respectively 2.54 (1.27, 5.07) and 2.92 (1.45, 5.87) for florfenicol, 0.57 (0.12, 2.63) and 3.63 (1.41, 9.32) for trimethoprim, and 3.00 (1.56, 5.76) and 1.99 (0.99, 4.01) for sum of veterinary antibiotics. Similar results were found when the outcome used WC-based obesity risk. The associations were sex related and mainly observed in boys.ConclusionsSome types of antibiotic exposure, which were mainly from food or drinking water, were associated with an increased risk of obesity in school children. Due to the cross-sectional design, more longitudinal and experimental studies are warranted to further test these findings.  相似文献   

8.
4-Nonylphenol (NP) and bisphenol A (BPA) are phenolic substances used in high volumes by the industry. Studies on cells and in experimental animals have shown that both these compounds can be classified as estrogenic hormone disrupters. Information about the exposure of humans to NP and BPA is still scarce, especially regarding levels in human blood. The first aim of this study was to investigate possible sources of NP and BPA exposure from food, by analyzing the levels of NP and BPA from a Swedish food market basket, based on the Swedish per capita food consumption. A second aim was to investigate blood serum levels of NP and BPA, as well as NP-ethoxylates, among young women in Sweden (n = 100). Moreover, associations between food consumption and blood NP and BPA levels were studied. In food, NP was to some extent found at levels above limit of quantification (LOQ 20 ng/g fresh weight) in fruits, cereal products, vegetables, and potatoes. BPA levels above LOQ (2 ng/g fresh weight) were found in fish, meats, potatoes, and dairy products. The estimated mean intakes per capita were (medium bound) 27 μg NP/day and 3.9 μg BPA/day, showing that food is a source of BPA and NP in the general Swedish population. In blood serum, free NP above limit of detection (LOD 0.5 ng/g) was detected in 46% of the study participants while detectable levels of total NP (LOD 0.8 ng/g) were observed in 43%. The corresponding percentages for BPA were 25% and 22%, respectively. The results indicate that there is a continuous source of exposure to NP and BPA that is high enough for free NP and BPA to be detected in some consumers. Among the participants with quantifiable levels of free and total NP (n = 38), 85% (median, range: 38–112%) of the NP was present as free NP. For BPA 76% (49–109%) was detected as free BPA (n = 15). All women had levels of ethoxylates of NP below LOD (0.1–0.7 ng/g). A significantly higher total consumption of fruits and vegetables was reported in questionnaires by participants with NP levels at or above LOD than among women with levels below LOD. This result is supporting the market basket results of relatively high NP levels in these types of food.  相似文献   

9.
Eight organic UV filters and stabilizers were quantitatively determined in wastewater sludge and effluent, landfill leachate, sediments, and marine and freshwater biota. Crab, prawn and cod from Oslofjord, and perch, whitefish and burbot from Lake Mjøsa were selected in order to evaluate the potential for trophic accumulation. All of the cod livers analysed were contaminated with at least 1 UV filter, and a maximum concentration of almost 12 μg/g wet weight for octocrylene (OC) was measured in one individual. 80% of the cod livers contained OC, and approximately 50% of cod liver and prawn samples contained benzophenone (BP3). Lower concentrations and detection frequencies were observed in freshwater species and the data of most interest is the 4 individual whitefish that contained both BP3 and ethylhexylmethoxycinnamate (EHMC) with maximum concentrations of almost 200 ng/g wet weight. The data shows a difference in the loads of UV filters entering receiving water dependent on the extent of wastewater treatment. Primary screening alone is insufficient for the removal of selected UV filters (BP3, Padimate, EHMC, OC, UV-234, UV-327, UV-328, UV-329). Likely due in part to the hydrophobic nature of the majority of the UV filters studied, particulate loading and organic carbon content appear to be related to concentrations of UV filters in landfill leachate and an order of magnitude difference in these parameters correlates with an order of magnitude difference in the effluent concentrations of selected UV filters (Fig. 2). From the data, it is possible that under certain low flow conditions selected organic UV filters may pose a risk to surface waters but under the present conditions the risk is low, but some UV filters will potentially accumulate through the trophic food chain.  相似文献   

10.
Planning for adaptation to climate change is often regarded to be a local imperative and considered to be more effective if grounded on a solid evidence base and recognisant of relevant climate projections. Research has already documented some of the challenges of making climate information usable in decision-making but has not yet sufficiently reflected on the role of the wider institutional and regulatory context. This article examines the impact of the external institutional context on the use and usability of climate projections in local government through an analysis of 44 planning and climate change (adaptation) documents and 54 semi-structured interviews with planners in England and Germany conducted between July 2013 and May 2014. We show that there is little demand for climate projections in local adaptation planning in either country due to existing policy, legal and regulatory frameworks. Local government in England has not only experienced a decline in use of climate projections, but also the waning of the climate change adaptation agenda more widely, amidst changes in the planning and regulatory framework and severe budget cuts. In Germany, spatial planning makes substantial use of past and present climate data, but the strictly regulated nature of planning prevents the use of climate projections, due to their inherent uncertainties. Findings from the two countries highlight that if we are to better understand the usability of climate projections, we need to be more aware of the institutional context within which planning decisions are made. Otherwise we run the risk of continuing to provide tools and information that are of limited use within their intended context.  相似文献   

11.
To date, personal volatile organic compounds (VOCs) exposure and residential indoor and outdoor VOCs levels have not been characterized in Korea. In this study, residential indoor and outdoor VOCs concentrations were measured and compared simultaneously with the personal exposure for each of 30 participants in a medium city, Asan, and in a metropolitan city, Seoul. Factors that influence personal VOCs exposures were assessed in relation to house characteristics and time activity information. All VOC concentrations were measured using passive samplers during a 24-h period and analyzed using GC-MS. Ten target VOCs were benzene, trichloroethylene, toluene, o-xylene, p-xylene, ethylbenzene, MIBK, n-octane, styrene, and 1,2-dichlorobenzene. Residential indoor and outdoor VOCs concentrations measured in Seoul were significantly higher than those in Asan. Indoor/outdoor (I/O) ratios for all target compounds ranged from 0.94 to 1.51 and I/O ratios of Asan were a little higher than those of Seoul. Results indicate that time activity information can be used to predict personal exposures, although such predictions will result in an over estimation compared to measured exposures. Factors which influence the indoor VOCs level and its personal exposure in relation to house characteristics included house age, indoor smoking, and house type.  相似文献   

12.
The political decision concerning modernization of Russian economy is impossible to implement without ecomodernization. The development of more efficient industrial, transportation, and agricultural technologies should be coordinated with measures to support natural self-regulation in ecosystems. Consideration is given to errors and misjudgments made in the course of modernization and possible measures to optimize and scientifically support this process in the interests of advancement in hunting and game management.  相似文献   

13.
Smallholder farmers play an important part in the dairy value chain in Sub-Saharan Africa. Three technological approaches have been used to improve productivity. These are through, applying agricultural ecological processes (ecological intensification), utilising modern livestock breeding (genetic intensification), and socio-economic intensification. Ecological intensification includes continuous housing of cows applying a cut-and-carry feeding system, introduction of purpose-bred forages and pastures, and the introduction of agro-forestry within the dairy systems. Genetic intensification strategies include: importation of dairy breeds such as Holstein–Friesian (HF) and cross-breeding of the indigenous breeds with HF. Training and capacity-building activities to create sustainable livelihoods have been initiated for farming and technological practices of animal husbandry, but also to enhance appropriate leadership and corporative-building skills that would create and support an enabling environment for sustainability. These improvements and initiatives in the service delivery have been championed by national governments, development partner institutions, or non-governmental organisations through different programmes. Challenges of intensification include matching management to genetic potential of imported and cross-bred improved dairy breeds, ensuring low post-harvest losses, proper utilisation, and reducing environmental impact. Using examples from Kenya, Malawi, Mozambique, Tanzania, and Zambia, this paper reviews the management and assessment approaches used in fostering smallholder dairy development strategies and dairy’s contribution to sustainable livelihoods in the face of intensification.  相似文献   

14.
Abstract

Population, resources and environment constitute the basis for economic and social advances. Their coordinative development is the key factor for the continuous, stable and harmonious development of economy and society. China is a developing country which needs to mobilize the whole society to coordinate among population, resources and environment and to keep publicity and research in pace so as to deepen people's understanding and improve the methods of achieving this coordination.  相似文献   

15.
Concentrations of 90Sr, 210Po and 210Pb in lichen and reindeer were studied in central (Østre Namdal) and southern Norway (Vågå) during 2000–2003. The study focussed on potential differences in concentrations of these nuclides in reindeer of different ages. Concentrations of 90Sr in bones of ∼10 year old adult females were about 40% higher than those in calves' antlers (90Sr concentrations in antlers and bones of calves are similar), while the available data from Vågå suggest that 90Sr concentrations in reindeer calves decreased with an effective ecological half-time of 9.03 ± 0.06 years during 1988–2002. Furthermore, 90Sr concentrations were 50–80% higher in bone of reindeer of a similar age from Vågå compared to those from Østre Namdal. Concentrations of 210Po and 210Pb in muscle and liver tissues were comparable to those reported for reindeer in other Nordic areas, with no significant difference in 210Po and 210Pb concentrations between adults and calves or between reindeer from the two different study areas.  相似文献   

16.
This study summarizes the spatial and temporal trends of fallout (137)Cs concentrations in caribou and reindeer (Rangifer tarandus ssp.), reported in various programs in Canada, Alaska and Greenland, over a 40-y period. During the 1960s, the highest (137)Cs concentrations (2000-3000Bqkg(-1) wet weight in muscle) were found in the large caribou herds of central northern Canada, with levels about 50% lower in Alaska and Greenland. Concentrations varied by up to a factor of 6 between spring and fall. Concentrations in reindeer were comparable to those in caribou from the same regions. The highest (137)Cs concentrations (750Bqkg(-1)) in the late 1980s were found in the Caniapiscau herd of central Québec. The contribution from the Chernobyl accident in 1986 was estimated from (134)Cs measurements to be 10-40% of the total (137)Cs. Present concentrations have declined to 200-300Bqkg(-1). The effective half-life (T(eff)) of (137)Cs in Canadian caribou herds was estimated to be about 6 y. The potential impact on the health of northern residents is discussed.  相似文献   

17.
Di-(2-ethylhexyl) phthalate (DEHP) has been used worldwide in various products for many years. In vitro studies have shown that exposure to DEHP and its metabolite mono(2-ethylhexyl) phthalate (MEHP) induces endothelial cell apoptosis. Moreover, exposure to DEHP had been linked to cardiovascular risk factors and cardiovascular diseases in epidemiological studies. Circulating microparticles have been known to be indicators of vascular injury. However, whether DEHP or its metabolites are independently associated with microparticles in humans remains unknown. From 2006 to 2008, we recruited 793 subjects (12–30 years) from a population-based sample to participate in this cardiovascular disease prevention examination. Each participant was subjected to interviews and biological sample collection to determine the relationship between concentrations of DEHP metabolites MEHP, mono(ethyl-5-hydroxyhexyl) phthalate, and mono(2-ethly-5-oxoheyl) phthalate in urine and concentrations of endothelial microparticles (CD62E and CD31 +/CD42a −), platelet microparticles (CD62P and CD31 +/CD42a +), and CD14 in serum. Multiple linear regression analysis revealed that an ln-unit increase in MEHP concentration in urine was positively associated with an increase in serum microparticle counts/μL of 0.132 (± 0.016) in CD31 +/CD42a − (endothelial apoptosis marker), 0.117 (± 0.023) in CD31 +/CD42a + (platelet apoptosis marker), and 0.026 (± 0.007) in CD14 (monocyte, macrophage, and neutrophil activation marker). There was no association between DEHP metabolite concentration and CD62E or CD62P. In conclusion, a higher MEHP concentration in urine was associated with an increase in endothelial and platelet microparticles in this cohort of adolescents and young adults. Further studies are warranted to clarify the causal relationship between exposure to DEHP and atherosclerosis.  相似文献   

18.
Soil samples collected from locations in Kosovo where depleted uranium (DU) ammunition was expended during the 1999 Balkan conflict were analysed for uranium and plutonium isotopes content (234U, 235U, 236U, 238U, 238Pu, (239 + 240)Pu). The analyses were conducted using gamma spectrometry (235U, 238U), alpha spectrometry (238Pu, (239 + 240)Pu), inductively coupled plasma-mass spectrometry (ICP-MS) (234U, 235U, 236U, 238U) and accelerator mass spectrometry (AMS) (236U)). The results indicated that whenever the U concentration exceeded the normal environmental values (approximately 2 to 3 mg/kg) the increase was due to DU contamination. 236U was also present in the released DU at a constant ratio of 236U (mg/kg)/238U (mg/kg) = 2.6 x 10(-5), indicating that the DU used in the ammunition was from a batch that had been irradiated and then reprocessed. The plutonium concentration in the soil (undisturbed) was about 1 Bq/kg and, on the basis of the measured 238Pu/(239 + 240)Pu, could be entirely attributed to the fallout of the nuclear weapon tests of the 1960s (no appreciable contribution from DU).  相似文献   

19.
Laboratory studies carried out in sound chambers give experimental support to the theory that fatigue and wakefulness could be influenced by sound and hearing. The tiring effect is more pronounced during exposure to low frequency noise compared to higher frequencies. A tiring effect was observed at lower levels above the hearing perception curve. As expected, when the sound pressure level was raised or the frequency was increased, stress reactions and alertness was a more frequently occurring effect. The laboratory findings were supported by a field study carried out on lorry drivers. The tiring effect was more pronounced when driving lorries generating higher levels of low-frequency noise compared to lorries generating lower levels.  相似文献   

20.
Over 114 different human enteric viruses are known. They are all excreted into sewage, and opportunities exist for them to find their way into water distribution systems. The characteristics of the illnesses caused by enteric viruses make their transmission by water difficult to recognize. Methods are not available for isolating all of the enteric viruses from water, so that finding any type of human virus in drinking water is an indication that other types may also be present. With improvements in technology, our laboratory has recently been able to detect group B coxsackieviruses, rotaviruses, and hepatitis A virus in chlorinated drinking water. At present, there are no uniform methods for concentrating, isolating, and identifying viruses in water. Emphasis should be placed on seeking uniformity in methods so that standards can be set for viruses in water.  相似文献   

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