Metals and health: a clinical toxicological perspective on tungsten and review of the literature.

Tungsten and tungsten compounds are considered toxicologically relatively safe. Concern regarding the potential health and environmental effects of depleted uranium and lead in military applications has lead many countries to explore the possibility of applying toxicologically safer metals. Heavy metal tungsten alloy-based munitions have been therefore introduced as a replacement in munitions and as kinetic energy penetrators. Although the toxicological profiles of all these metals are well known, their internalization as embedded shrapnel may be considered a new route for long-term exposure. Studies in experimental animals and cell culture indicate that pellets based on heavy metal tungsten alloy possess carcinogenic potential previously unseen for depleted uranium and/or lead. Other metals in the tungsten alloy such as nickel or cobalt may contribute to such a risk. Accordingly, the long-term tungsten-related health risk is reason for concern. This article reviews toxicological and clinical literature and provides new perspectives on tungsten and tungsten-based alloys.