What are Heavy Metals? (Lead and Mercury)

Heavy metals include lead, mercury and aluminium, all of which are toxic and negatively affect the body.



Lead (Pb) and lead compounds can be ingested via food, inhaled or enter the body via the skin and can result in chronic poisoning over time. Lead accumulates in bone tissue instead of calcium, making removal of it difficult and slow. It damages the central and peripheral nervous systems, impairs the formation and development of blood cells and leads to digestive problems and kidney damage. With very few exceptions, lead compounds are classified as toxic for reproduction (teratogenic and harmful to fertility).

Red Lead

The symptoms of lead poisoning can include:

  • High blood pressure
  • Abdominal pain
  • Constipation
  • Joint pains
  • Muscle pain
  • Declines in mental functioning
  • Pain, numbness or tingling of the extremities
  • Headache
  • Memory loss
  • Mood disorders
  • Reduced sperm count, abnormal sperm
  • Miscarriage or premature birth in pregnant women

Mercury (IV) flouride


Mercury (Hg) is a toxic heavy metal. Metallic mercury is liquid at room temperature and is relatively harmless in this state under normal pressure conditions. However, it evaporates at room temperature and forms poisonous fumes. Organic compounds of mercury such as dimethylmercury are particularly toxic. Poisoning is often caused by the direct absorption of vapours of mercury, known as an acute poisoning. Chronic poisoning by low doses of mercury through food and drink are much more common. The controversial amalgam (fillings which contain mercury) used in dentistry is often discussed as a cause of chronic mercury poisoning.

Mercury sulfide

The symptoms of mercury poising can include:

  • Skin rashes and dermatitis
  • Memory loss
  • Muscle weakness
  • Tremors
  • Emotional changes (e.g., mood swings, irritability, nervousness, excessive shyness)
  • Insomnia
  • Neuromuscular changes (such as weakness, muscle atrophy, twitching)
  • Headaches