Mercury is a heavy metal known to be highly toxic to human health and other animals. However, we are exposed to small or large levels of this element, depending on our habits. After all, this metal can even be found in foods, such as fish, that are considered healthy to eat. The problem is usually the quantity.
In case of inhalation or ingestion of large amounts of mercury, the risk of life for the person is high. This is because the metal causes neurological damage. Initially, the most common symptoms are: tremors, insomnia, memory loss, headaches and muscle weakness. However, exposure can cause permanent damage to the body or even cause death.
Although quite serious, the danger is not limited to living things. If soil is exposed to too much mercury, it tends to become poor and barren. In case of water contamination, it can lead to the death of different species of aquatic fauna and, when it reaches the groundwater, it makes it unsuitable for consumption. Basically, the entire ecosystem is at risk.
Below, see the five most common ways of mercury exposure that threaten both human health and planet Earth, according to the United Nations Environment Program (UNEP):
1. Fish consumption
Among the most common forms of mercury exposure is the consumption of contaminated fish or seafood. “As mercury ‘accumulates’ up the food chain, larger fish such as shark, swordfish, tuna and marlin tend to be particularly high in mercury,” explains UNEP. In Brazil, dogfish can show high concentrations of the heavy metal.
2. Cosmetics and beauty products
Although the dangers of mercury are well known, the metal is still used in cosmetics and beauty products, especially in skin whitening creams and cleaning products. However, some countries already have strict laws that prohibit the use of this type of substance in the formulation. In Brazil, use is no longer allowed.
To cheaply separate the gold from the gravel, small-scale or illegal mining uses mercury, which endangers the entire ecosystem of an area – after all, the metal pollutes the soil as well as rivers and groundwater, as seen in the Amazon – in addition to the lives of these workers and nearby (indigenous) communities. Among these people, there is a risk of mercury poisoning.
4. Combustion of coal
Another way of releasing mercury is by burning coal. “The 2018 Global Mercury Assessment concluded that coal burning and other forms of fossil fuel and biomass burning are responsible for about 24% of global mercury emissions,” says UNEP.
Although this is not the case in Brazil, which has an energy matrix based on hydroelectric plants – a renewable and clean source – burning coal is recurrent in many countries. With the war in Ukraine and blockages in natural gas distribution, many European countries have favored this highly polluting energy source in recent months.
5. Dental amalgam and thermometers
In addition to all the above-mentioned points of exposure, mercury can be found in more subtle and almost imperceptible places, such as in people’s mouths. This is because its use is relatively common in the restoration of teeth through dental amalgam. Older thermometers also use heavy metal in their composition. Although these two uses are in decline and unlikely to pose a health risk in small amounts, they demonstrate that exposure to the element is much more common than one might think.