Environmental quality and safety最新文献

A survey is given on reported PCB-residues and accumulation in various environmental media including water and aquatic environment, flora, animals, food, and humans. Model studies with technical PCB, as well as with pure individual components, are presented from various working groups. As examples, metabolic studies and photochemical experiments are discussed. According to our present knowledge, a major metabolic pathway in animals and plants is hydroxylation, often followed by methylation or conjugation. By UV-irradiation, however, oxygenation, dechlorination and chlorination, polymerization and isomerization may occur.

No data are available on Selenium concentration in the Italian environment in spite of its importance as an essential and toxic element. In order to get some information about the concentration and distribution of this element in the environment and in the food-chain, a survey has been made in the Monte Amiata area (Toscana, Italy). Such an area was selected for this study owing to its large mineralization due to many elements (e.g. Fe, Cu, Ag, Sb and particularly Hg). The selenium content has been determined by thermal neutron activaltion analysis and a large volume high-resolution Ge-Li gamma ray spectrometer connected on line to a DEC PDP 8/L computer. The instrumental method requires neither a chemical separation technique nor a pre-or post-concentration of Selenium. The Selenium concentration for wet weight in foodstuffs ranges between a value of 0.008 ppm in milk and a value of 0.2 ppm in chicken. The average Se intake for the population living in the area under investigation has been also estimated. A critical discussion of the data is reported together with a comparison with the Se concentration values referring to other countries.

Certain climatic and edaphic conformations in the Bavarian sub-alpine mountains and in the Alps favor above all the development of a land utilization system and farm structures similar to those in the northern part of Scandinavia. In 1963/64, the years of the highest environmental contamination up to the present, we established in 600 beef samples from the round or shoulder of male and female cattle (mainly Highland cattle) close connections between the 137Cs-contamination of green crop and the long lastnig yearly precipitation quantities, as well as certain relations between the 137Cs-contamination of meat and differences in the feeding and keeping of the animals. During summer-seasons (April-October), beef of cattle from pastures with heavy rainfall (Alps) was contaiminated by 137Cs up to 15 times more than that of confined animals. Hereby the rate of 137Cs-contamination in the meat of grazing cattle was nearly proportional to the quantities of precipitation. When confined cattle were fed on pastures in autumn after harvesting for 2 to 3 weeks, a quick increase of 137Cs-contamination of the meat was caused within this time up to values which in this district were otherwise only observed in grazing cattle. The lower 137Cs-content in meat of cattle housed during the summer season is due to the more varied fodder, which is at that time less contaminated than green crop. During the winter season (November to March), the highest contaminations in the meat of confined (Bohemian Forest) or grazing cattle (Alps) was measured when the animals in these districts were almost exclusively fed with fodder from the own farmground or with leafy silage. The highest contamination was almost regularly noticed in January, February and March, as generally during these months the highly contaminated first cut hay is fed. Here the meat was often even more contaminated than that of grazing cattle. After the quick decrease of 137Cs in fallout noticed in the years 1964 and 1965, in 1965/66 a dependance in the 137Cs-contamination of beef on the methods of keeping and feeding could still be observed in only the extreme cases (Alps, Bavarian- and Bohemian Forest); though in general, meat of animals from districts with heavy rainfall was slightly more contaminated than meat of animals from regions with less precipitation.

Since 1963, air quality in the Rhine-Ruhr-area, one of the largest agglomerations of industry, population, and traffic in Europe, is systematically monitored and the levels are documented in the form of on air pollution cataster. The surveilled area comprises about 5000 km2. Within the first years, measurements were made with the air pollutants sulphur dioxide and dust fall out. Later, the following air pollutants were included into the monitoring program: Hydrogen fluoride, hydrogen chloride, suspended particles, as well as the determination of total organic substances. In smaller regions within the surveilled area, measurements of the following air polutants were made, too: Nitrogen monoxide, nitrogen dioxide, hydrogen sulphide, carbon disulphide, benzene, phenol, carbon monixide, oxidants, as well as determinations of lead, cadmium, and zinc content in suspended particles and dust fall out. Besides the demonstration of the tasks within the air quality monitoring program, the projection as well as the execution of air pollution measurements are discussed. Definitions of impact characteristics and the adjusted legal air quality standards are given in more detail. Finally, an evaluation of the results of this monitoring program is given for each pollutant. Furthermore, the trends of air pollution and its causes since the beginning of air quality monitoring in 1963 are evaluated.

This report concerns the frequency of cancers in an aldehyde factory. The epidemiological evidence raises the suspicion that acetaldol is a possible carcinogen. There may be also syncarcinogenic effects of some aliphatic aldehydes, probably in combination with some air pollutants.