What are Heavy Metals?

Heavy metals are metallic elements with a high density, specific gravity or atomic weight. They are also toxic, posing environmental or health hazards when they are not controlled.

The most commonly known heavy metals include mercury, lead, chromium, copper, zinc, arsenic, silver, vanadium and nickel. While we will come into contact with most of these metals on a daily basis (except arsenic, hopefully!), they are only harmful if they enter the ecosystem or are ingested.

Heavy metal consumption

Consuming heavy metals in high volumes can lead to serious health problems. Vanadium is used to produce alloys for vehicles, and is known to cause respiratory problems when inhaled. Manganese is typically used to make batteries and it has been linked to Parkinson’s disease. Copper consumption can contribute to the onset of rheumatoid arthritis and heart disease, and may be linked with various types of cancers.

Clearly heavy metals should be kept well away from our digestive systems. However, back in 2008, British scientists reported that more than 100 different red and white wines contained potentially dangerous levels of heavy metals, including vanadium, copper and manganese. Luckily, since then checks have been put in place to prevent an excessive amount of heavy metals entering the food chain. Read this article, In Wine There is Truth - The Characterisation and Quantitative Analysis of Wine Using Spectroscopic Methods, to learn more about how heavy metals are detected in the wine making process.

Why are heavy metals bad for us?

While these are all naturally occurring elements, due to their high value and versatility, mining and over-consumption has resulted in dangerously high concentrations of heavy metals becoming embedded in the food cycle. For instance, mercury is used to make a neon light. The light breaks and is dumped in the ocean. A shoal of fish absorbs some of the leaking mercury. The fish are caught and eaten, resulting in an epidemic of mercury poisoning.

Why are they good for us?

However, in small quantities, heavy metals are actually good for us and can bolster the immune system, protecting us from potential heavy metal poisoning in the future. Zinc, for instance, does not occur naturally in the body, but is thought to have a huge range of health benefits including reducing wrinkles in the skin, treating diarrhoea and supporting the immune system.

How to identify heavy metals

In laboratories it is easy to identify heavy metals, but in day to day life it is a lot harder. New tools are being developed all the time to test for heavy metals and other potentially dangerous compounds. For a more detailed insight into these latest developments, read New Tools to Quickly Identify Unknown Compounds in Complex Food.