In 2018 the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area re‐evaluated lead and its compounds and has derived a biological guidance value at the workplace (BLW) for the blood concentration of lead. Available publications are described in detail. The re‐evaluation is entirely based on studies in humans. The following critical health effects were considered: effects on heme synthesis, behavioural toxicity/neurotoxicity, male fertility, developmental toxicity, nephrotoxicity, cardiovascular effects, genotoxicity/carcinogenicity.
Effects on neurobehaviour and nephrotoxicity have been described at blood levels around 300 µg Pb/L and higher. Therefore, a BLW of 200 µg Pb/L blood has been deduced. As investigations of lead‐exposed workers show no statistical increase in lymphocyte micronuclei at this blood level, it is reasonably expected that the proposed BLW will also minimize a lead‐induced genotoxic/carcinogenic risk.
For women a Biological Reference Value (BAR) of 70 µg Pb/L blood is proposed, based on the 95th percentile of lead blood levels of the general population in Germany.
Because of the long persistence of lead in the body, the sampling time is not fixed.