通过调节汽油中铅的使用来控制人体血铅浓度

在20世纪60～70年代,铅排放一直保持着最大速率,之后,由于工业国家采取了日益严格的政策来限制铅作为防爆剂在汽油中使用,使得含铅汽油已经变得很少见了.我们利用欧洲铅排放量(PbE)和空气浓度(PbC)的重建及对约1980年以来德国人体血铅浓度(PbB)的重复测定,建立了一个可由铅排放量(PbE)估计人体血铅浓度(PbB)的经验模型.采用这一模型有两种用途[1]估计六七十年代德国的PbB水平,当时铅排放量最大而人体血铅水平监测尚未开始.结果显示,血铅峰值已经达到了卫生官员认为对胎儿和儿童有潜在危害的平均水平.[2]估计PbB水平将如何因有关汽油中铅使用的法规的实施而变化.模型估计,如果没有或延迟法规,PbB水平将远远超过临界水平.因此,自20世纪70年代以来,德国制定的法规已经明显降低了铅对健康的危害.     

Where is everybody?

In our Galaxy we expect about 10⁹ habitable planets, similar to our Earth but mostly a few 10⁹ years older. If we generalize our own case and present state, we should try by all means to take up radio contact with the other civilizations. But if we generalize our probable future technical activities, the Galaxy should be teeming with life, of which we have seen no sign so far, and all habitable planets including Earth should have been colonized long ago by others, which certainly is not the case. This is considered a severe puzzle: it seems difficult to avoid the conclusion of our uniqueness, but even more difficult to accept and explain it.     

CCall--healthy and successful work in call centres.

Call centre workplaces are in many ways a challenge to occupational health and safety. The occupation itself can be described as an IT information technology-supported, communication-intensive form of work with often unusual working hours and a high rate of part-time employment. Data on the employee turnover as well as absenteeism related to occupational disability is quite contradictory. Occupational safety and its proponents still have to find new ways into the corporate structures and cultures of this relatively new and rapidly growing branch of industry. In a 2-year research and development project, using a holistic approach and under consideration of all the relevant disciplines, call centre workplaces were studied, and organisational measures were developed and field tested by putting them into practice. Practical help was developed for a sustainable strategy for successful and healthy work in call centres.     

Detection Method for Avian Influenza Viruses in Water

Recent events have shown that humans may become infected with some pathogenic avian influenza A viruses (AIV). Since soil and water, including lakes, rivers, and seashores, may be contaminated by AIV excreted by birds, effective methods are needed for monitoring water for emerging viruses. Combining water filtration with molecular methods such as PCR is a fast and effective way for detecting viruses. The objective of this study was to apply a convenient method for the detection of AIV in natural water samples. Distilled water and lake, river, and seawater were artificially contaminated with AIV (H5N3) and passed through a filter system. AIV was detected from filter membrane by real-time RT-PCR. The performance of Zetapor, SMWP, and Sartobind D5F membranes in recovering influenza viruses was first evaluated using contaminated distilled water. SWMP, which gave the highest virus recoveries, was then compared with a pre-filter combined GF/F filter membrane in a trial using natural water samples. In this study, the cellulose membrane SMWP was found to be practical for recovery of AIVs in water. Viral yields varied between 62.1 and 65.9% in distilled water and between 1 and 16.7% in natural water samples. The borosilicate glass membrane GF/F combined with pre-filter was also feasible in filtering natural water samples with viral yields from 1.98 to 7.33%. The methods described can be used for monitoring fresh and seawater samples for the presence of AIV and to determine the source of AIV transmission in an outbreak situation.     

Natural and man-made organobromine compounds in marine biota from Central Norway

Brominated organic pollutants were found in selected samples of mollusk tissue, fish liver, as well as in the eggs and livers of shag from three sites in Central Norway. More than 80 organobromines were identified owing to the defined isotope ratio acquired by GC/ECNI-MS. However, only a few peaks could be assigned to anthropogenic brominated flame retardants (polybrominated diphenyl ethers). Most of the organobromine compounds detected were unknown or halogenated natural products. The known halogenated natural products MHC-1 and TBA were abundant in all samples and usually between equally abundant, and up to 50 fold more concentrated than the major polybrominated diphenyl ether congener BDE 47. The halogenated natural products BC-2 (2-MeO-BDE 68) and BC-3 (6'-MeO-BDE 47), were on level with BDE 100 which was the second most abundant BDE congener in many samples. The previously identified natural polybrominated hexahydroxanthene derivatives (PBHDs) were detected for the first time in bird eggs. Being major contaminants in bird eggs, PBHDs were only present at low levels in bird liver from nestlings originating from the same clutch. Such differences were detected for several other major contaminants. One unknown tetrabromo compound particularly abundant in mussels from Munkholmen was studied by GC/MS and the molecular ion was detected at m/z 446. The abundance of the most important unknown compounds did not correlate with BDEs and they most likely represent halogenated natural products. This study supports that halogenated natural products have to be treated as serious contaminants of marine coastal waters. Our data suggest that their abundance is highest in habitats along the shoreline. Thorough examination of these compounds in environmental samples is an important task.