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101.
In 1996 the Swedish Poisons Information Centre performed a follow-up study concerning poisonings related to ‘do-it-yourself’ activities. The study was supported by the National Institute of Public Health in Sweden. The objectives were to investigate and define monthly variations, route of exposure, type of products and, in particular, exposures to corrosives, age and sex groups, place of treatment, severity of symptoms, place of the accident, special risk products and risk situations. The Poisons Information Centre was contacted concerning 1609 cases, with a peak during the summer months. There was no or uncertain connection between exposure and symptoms in 117 cases. This means that 1492 cases were left to study. Inhalation and eye exposure were the predominant routes, followed by skin exposure and ingestion. Cleaning agents were the most common type of products involved. Of the 1492 cases included in the study 1033 were possible to follow up. Among these, 20–29 year olds and 30–39 year olds predominated, and there was a dominance for men. In total, 28% of those exposed were subject to medical attention, either in hospital or in outpatient clinics. According to the Poisoning Severity Score 78% had mild (grade 1) and 7% moderate (grade 2) symptoms. There were no severe intoxications and no deaths. Severity grade 2 occurred 3.6 times more often among those with exposures involving risk of corrosive damage than among others in the study population. Most accidents occurred in the home. Special risk products and risk situations were exposure to corrosive products, release of chlorine when mixing hypochlorite and acid, ‘fire-eating’, siphoning gasoline and diesel fuel, welding, and inhalation of carbon monoxide from exhaust gases. The Swedish Poisons Information Centre registered 1609 cases of poisoning accidents during ‘do-it-yourself’ activities, which means an average of four to five cases per day. Although this type of accidents is not uncommon, significant poisoning seems to be rare. Some special risk situations were identified.  相似文献   
102.
Oil pollution from various sources, including exploration, production and transportation, is a growing global concern. The highest toxicity of hydrocarbon pollutants is associated with the water-soluble phase compounds, including naphthenic acids, a known component found in all hydrocarbon deposits. Recently, naphthenic acids (NAs) have shown estrogenic and anti-androgenic effects in vitro. For this reason we investigated the potential effects of two commercial mixtures of naphthenic acids on fish in vivo, using the three-spined stickleback (Gasterosteus aculeatus) as a model species.  相似文献   
103.
The 137Cs and 210Pb dating of a 61-cm long sediment core retrieved from a drinking water reservoir (Lake Brêt) located in Switzerland revealed a linear and relatively high sedimentation rate (~1 cm year?1) over the last decades. The continuous centimeter scale measurement of physical (porewater and granulometry), organic (Corg, P, N, HI and OI indexes) and mineral (Cmin and lithogenic trace elements) parameters therefore enables reconstructing the environmental history of the lake and anthropogenic pollutant input (trace metals, DDT and PCBs) at high resolution. A major change in the physical properties of the lowermost sediments occurred following the artificial rise of the dam in 1922. After ca. 1940, there was a long-term up-core increase in organic matter deposition attributed to enhance primary production and anoxic bottom water conditions due to excessive nutrient input from a watershed predominantly used for agriculture that also received domestic effluents of two wastewater-treatment plants. This pattern contrasts with the terrigenous element input (Eu, Sc, Mg, Ti, Al, and Fe) which doubled after the rising of the dam but continuously decreased during the last 60 years. By comparison, the trace metals (Cu, Pb and Hg) presented a slight enrichment factor (EF) only during the second part of the 20th century. Although maximum EF Pb (>2) occurred synchronously with the use of leaded gasoline in Switzerland (between ca. 1947 and 1985) the Hg and Cu profiles exhibited a relatively similar trend than Pb during the 20th century, therefore excluding the alkyl-lead added to petrol as the dominant (atmospheric) source of lead input to Lake Brêt. Conversely, the Cu profile that did not follow the decrease registered in Pb and Hg during the last 10 years, suggests an additional source of Cu probably linked to the impact of agricultural activities in the area. In absence of heavy industries in the catchment, the atmospheric deposition of DDT and PCBs via surface runoff followed the historical emissions of POPs in Switzerland. Such result highlights the regional contamination of freshwater resources by the large-scale emission of toxic industrial chemicals in the 1960s and 1970s as well as the efficiency of the regulatory measures subsequently taken.  相似文献   
104.
We investigated how morphological traits of territorial males in the polygynous bat Saccopteryx bilineata were related to their reproductive success. Because of the frequency of aerial courtship displays and defence manoeuvres, and the high energetic costs of flight, we expected small and symmetric males to be better able to court females on the wing and to monopolize copulations with females in their harems. We predicted that small and symmetric males would sire more offspring within the colony and a larger portion of the young born within their harem than large or asymmetric males. We measured size and fluctuating asymmetry of 21 territorial males and analysed their reproductive success in 6 offspring cohorts (n=209 juveniles) using 11 microsatellite loci. As predicted, small and symmetric males had, on average, a higher reproductive success in the colony than large and asymmetric males. The percentage of young sired by males within their harem increased as males decreased in size, but was not influenced by fluctuating asymmetry. As fluctuating asymmetry of males correlated with their reproductive success within the colony but not within their harems, we infer that fluctuating asymmetry is probably related to female choice, whereas male size is probably important for harem defence on the wing.Communicated by G. Wilkinson  相似文献   
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108.
The main physicochemical characteristics of the volcanic soil of Southern Chile, with allophane as the main pedogenic mineral phase were analysed and compared with common zeolites (clinoptilolite) of the European market. The ultimate goal of this study was to test volcanic soil for the use as mineral landfill liner. The main results indicated that the clay and silt fractions together of the volcanic soil were between 38 and 54%. The buffering capacity of the volcanic soil was higher compared with the studied zeolites, whereas the cationic exchange capacity of the volcanic soil (between 5.2 and 6.5 cmol + kg(-1)) is of the same order of magnitude of the studied zeolites (between 9.7 and 11.4 cmol + kg(-1)). Moreover, the anionic exchange capacity of the volcanic soil was higher compared to the zeolites analysed. The hydraulic conductivity of the volcanic soil, measured in the laboratory at maximum proctor density, ranges between 5.16 x 10(-9) and 6.48 x 10(-9) m s(-1), a range that is comparable to the value of 4.51 x 10(-9) m s(-1) of the studied zeolite. The Proctor densities of the volcanic soil are in a lower range (between 1.11 and 1.15 g ml(-1)) compared with zeolites (between 1.19 and 1.34 g ml(-1)). The volcanic soil physicochemical characteristics are comparable to all the requirements established in the Austrian landfill directive (DVO, 2000). Therefore, the use as mineral landfill basal sealing of the analysed volcanic soil appears reasonable, having a pollutant adsorption capacity comparable to zeolites. It is of special interest for Southern Chile, because there are no alternative mineral raw materials for basal liners of landfills.  相似文献   
109.
Developmental and reproductive processes are most sensitive to the toxic effects of environmental chemicals. Especially alarming is the fact that many groups of industrial chemicals and pesticides are capable of disrupting the endocrine system in man and animals. Of great concern is the reduction in the sperm count in Europe, but also the worldwide increase in a great number of reproductive and developmental disturbances observed in both man and wildlife. A correlation to a high chemical burden has been demonstrated for many different animal species as well as for women. An important consideration in assessing the potential effects of environmental chemicals on the endocrine system is the time at which such an exposure occurs. In the adult organism, hormones initiate functional processes; these effects are usually transient. In early life, hormones control developmental processes and are capable of producing permanent changes in organ structure and function (organizational effects). Therefore, chemical disruption of hormonal functions during development can result in permanent functional changes of the afflicted organ.  相似文献   
110.
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