We may, therefore, conclude that human exposures and tissue levels of dioxin are at or near those which are associated with adverse health effects in animal studies. Toxicity Elemental mercury from broken thermometers or sphygmomanometers easily vaporizes and is inhaled. Relatively low amounts may lead to kidney damage. Some studies of workers exposed to low levels of metallic mercury in the workplace show impaired psychological perfommance, memory, neuromuscular, and renal function. Mercury exposure may increase the risk of spontaneous abortion.
Organic mercury is of more concern at environmental levels.
Methylmercury from contaminated fish easily crosses the placenta and enters the brain of the developing fetus. It interacts with DNA and RNA and binds with sulfLydryl groups, resulting in changes in RNA and DNA synthesis. Depending on the developmental stage of the organism, methylmercury causes rnitotic arrest in neurons. The critical effect from prenatal exposure to methylmercury is psychomotor retardation. Fish advisories are intended to protect against this low-level effect.