For a long time, this heavy metal has been used in products such as batteries, amalgam dental fillings, pesticides, barometers, thermometers, disinfectants, lighting as well as vaccines.
Phenylmercury compounds have been used in the production of cladding, adhesives, sealants and polyurethane elastomers. Some of these uses have been restricted or completely prohibited; others still remain. However, it seems that a large part of the human exposure to this substance, in the dangerous form of methylmercury, comes from our food, especially fish. The presence of methylmercury in fish comes from environmental pollution caused by emissions and spills from coal-fired power stations and certain industries (e.g. alkaline chlorine industry which uses mercury cells). Mercury emissions can also come from waste incineration plants.
In 2005, the European Union introduced a strategy to reduce the environmental health issue of mercury. This strategy has had some positive effects such as restricting the sales of measuring equipment which use mercury. They have also tried to get industries to reduce their emissions.
Despite measures in place to limit or at least reduce the presence of this heavy metal, there is still a serious problem regarding mercury exposure through our food and some household products.
Mercury can be found in older objects e.g. thermometers, some old pigments and paints, household appliances, flame detectors, switches, button cell batteries etc. as well as in energy-saving light bulbs which can emit mercury if broken.
Although they are banned in many countries, and more so in the global market, some products can be found on the market which contain mercury e.g. certain skin-lightening products.
However, the main concern regarding mercury exposure is that of contaminated fish (e.g. tuna or swordfish) especially in countries like Spain where very high concentrations of this heavy metal have been detected. Scientists are especially worried about the effects that mercury exposure during pregnancy could have on children’s neurological development (e.g. cognition, memory, speech etc.)
Scientific investigations have found a link between mercury and various health problems including: acute tubular necrosis, behavioural problems, acute bronchitis, cerebral palsy, cognitive impairment (including learning difficulties, memory loss and poor attention span, mental retardation, delayed development, contact dermatitis, loss of coordination, hearing loss, Minamata disease, peripheral neuropathy, pneumonitis (hypersensitivity), psychiatric disorders (disorientation, hallucinations, psychosis, delirium, paranoia, anxiety and depression, emotional lability, mood swings, euphoria), convulsions and spasticity. There is also ample evidence to link mercury exposure to: changes in gender ratio, anaemia (including haemolytic anaemia), aplastic anaemia, autoimmune antibodies, chronic kidney disease, congenital defects, arterial coronary disease, peripheral vascular disease, atherosclerosis, visual impairments (including blindness, retinopathy and optic neuropathy), delayed development, fetotoxicity (miscarriages, foetal deaths), glomerulonephritis, immunosuppression, low birth weights, menstrual disorders (abnormal bleeding, short cycles, long cycles, irregular cycles, painful periods, neural tube defects or CNS defects, pneumonia and pulmonary oedema. Lastly, there are some studies which link this metal to: Lou Gehrig’s disease, brain tumours, erectile dysfunction, hormonal imbalances, hypertension, myocardial infarction, nephrotic syndrome, neurasthenia, pulmonary fibrosis, reduced male and female fertility, renal cancer, scleroderma and thyroid disorders e.g. hypothyroidism.