Unusual Non-Occupational Exposure to Metals

Exposure to metals at workplaces is well known and in many cases occupational studies led to an adoption of limit values. For airborne concentrations of substances as metals refer to the “Maximaleo Arbeitsplatz-Konzentration” (MAK) in Germany or the “Threshold Limit Value” (TLV) in USA. Biological monitoring consists of an assessment of overall exposure to chemicals at the workplace and in the environment. The “Biologischer Arbeitsstoff Toleranzwert” (BAT) in Germany and the “Biological Exposure Index” in the USA serve as reference values. Besides these occupational limit values, reference values exist in Germany for the background exposure of the non occupationally exposed general population. In some cases the reference values are exceeded without any occupational exposure. Several cases of unusual environmental exposure to cobalt, mercury and manganese are reported. In such cases, it is often difficult to evaluate the measured concentration. In Germany, therefore, the “Human-Biomonitoring-Werte” (HBMValues) have been adopted in order to evaluate such high background exposures. The HBM-concept is presented. Environmental exposure to metals is usual within some limits. Reference values are helpful for an assessment. Unusual exposure occurs and the physician should be alert to symptoms of poisoning

N‐Methyl‐2‐pyrrolidone : BAT Value Documentation, 2009

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated a biological tolerance value at the work place (BAT value) for N‐methyl pyrrolidone (NMP), considering 5‐Hydroxy‐N‐methyl‐2‐pyrrolidone (5‐HNMP) in urine to characterize the internal exposure. A BAT value for 5‐HNMP in urine can at present not be derived from effect parameters, but only on the basis of the correlation to the MAK value. According to Bader et al. (2007), an 8‐hour exposure to NMP at the level of the MAK value of 82 mg/m3 with an activity of 75W for one hour during the exposure interval results in a 5‐HNMP concentration of 153 mg/g creatinine (186 mg/l). According to Åkesson and Jönsson (2000) the expected 5‐HNMP concentration after 8 hours exposure to 82 mg NMP/m3 is 183 mg/g creatinine or 220 mg/l assuming a mean creatinine concentration of 1.2 g/l, performed at rest. Possibly, the differences of the corresponding results by Bader et al. (2007) can be attributed to the influence of an additional dermal absorption. On the basis of the results by Bader et al. (2007), a BAT value of 150 mg 5‐Hydroxy‐N‐methyl‐2‐pyrrolidone/l urine corresponding to the MAK value of 82 mg/m3 has been derived. Sampling time is at the end of exposure