Heavy metal poisoning
Overview
The body does not handle most heavy metals well, and excess levels are poisonous. Lead poisoning is well-known, but also potentially poisonous are mercury, thallium, arsenic, and even iron (e.g. iron tablets).
Symptoms
- Memory loss
- Speech difficulties
- Hypertension
- Fatigue
- Aggression
- Irritability
- Depression
- Chronic fatigue
Causes
- The most common cause of heavy metal poisoning is lead. The incidence of lead poisoning has been falling steadily in affluent countries, due to removal of lead from paint, petrol and food cans.[2]
- Lead poisoning remains a problem, however, in older housing where lead water pipes and lead paint may still be present. In housing such as this, there is a particular risk to children and the American Centre for Disease Control and Prevention recognised this and recommended screening of children in areas considered to pose a threat from this hazard, in order to prevent the children from developing neurological damage.[3]
- Other sources of lead poisoning are occupations (eg, smelting, battery manufacture), traditional remedies, or occasionally foreign bodies (lead weights).
- Mercury can be found in the elemental state (dental amalgam, thermometers), inorganic (industrial processes) and organic compounds (pesticides, wood preservatives, some medicines, and contaminated fish).
- Ingestion of disc batteries by children can also lead to heavy metal poisoning amongst other problems. These batteries can contain varying amounts of metals including mercury, manganese and cadmium.
- Poisoning from other heavy metals most often occurs in individuals regularly exposed to the metals in their work environment.
- Criminal poisoning with lead has been reported.