LIMPACT: Ein Expertensystem zur Abschätzung der Pflanzenschutzmittel-Belastung kleiner Fließgewässer mittels der Makroinvertebraten-Fauna

The development and the evaluation of a biological indicator system for pesticide pollution in streams are presented. For small headwater streams with an agricultural catchment area, the expert system LIMPACT estimates the pesticide contamination according to the four classes of Not Detected, Low, Moderate and High contamination without any specification of the chemical agents. The input parameters are the abundance data of benthic macroinvertebrate taxa within four time frames in a year (March/April; May/June; July/August; September/October) and 9 basic water-quality and morphological parameters. The heuristic knowledge base was developed with the shell-kit D3 and contains diagnostic rules with scores to either establish or de-establish a contamination class. We differentiate between positive indicator taxa, which indicate contamination by high abundance values and positive abundance dynamics, and negative indicator taxa, a high abundance of which rules out contamination and indicates an uncontaminated site. We analysed 39 taxa and found 13 positive and 24 negative indicators. The database is comprised of 157 investigations per stream and year. For the evaluation of LIMPACT, we used the same cases. The correct diagnosis for the 157 investigations per stream and year is established by LIMPACT in 66.7 to 85.5% of the cases, with better results for uncontaminated sites. In most of the remaining cases no diagnosis is established instead of an incorrect one.     

Platin im Regenabfluß einer Straße

Using platinum based catalytic converters, platinum is emitted with the exhaust gases and deposited on the roads, and in their vicinity (sewage treatment plants, rivers), which increases the platinum concentrations in aquatic eco-systems. To evaluate the platinum discharge from roads, the platinum concentration was measured in rainwater from a road with a traffic fre quency of 16,000 automobiles per day. The platinum content of the samples varies strongly dependent upon the previous dry period, and the intensity and duration of the rainfall. Platinum was measured in 18 run-off samples from various rainfall events. The maximum platinum concentrations showed values up to 1.1. μg/l. The median value was 15 ng/l. Analysis of a sample from one rainfall events shows that platinum has a well defined firstflush effect, similar to that of particular bound lead and copper. The good correlation between platinum and coarse suspended matter, coarse particular lead and copper indicates that platinum in road run-offs is frequently found to be particular bound. Under the assumption that the road has been completely washed off, the platinum deposition can be estimated to be 14 ng/(m²d).     

Total TEQ emissions (PCDD/F and PCB) from industrial sources

Flue gas samples from eight different sources (industrial plants and crematories) have been analyzed for PCDD/Fs and PCBs and total Toxicity EQuivalents (TEQ) values have been calculated using the latest WHO toxicity equivalent factors from 1998. A contribution of PCBs to the Total TEQ up to 16% was found, within the 12 WHO-PCBs PCB-126 contributes mostly to the TEQ. Thermodynamic stability of PCBs was calculated semiempirically using the MOPAC program package and differences in the heat of formation (HoF) were compared to the distribution of PCBs in real samples. Partial correspondence between fact and theory could be found.     

Rate of occupational accidents in the mining industry since 1950--a successful approach to prevention policy

This paper deals with the decrease in the rate of accident insurance claims in the German mining industry over the last five decades. It intends to show that this process is above all the result of a prevention policy where companies and the body responsible for the legal accident insurance in the mining industry, the Bergbau-Berufsgenossenschaft (BBG), work hand in hand. A system like the German accident insurance scheme, combining prevention, rehabilitation, and compensation, enables successful and modern safety and health measures.