Health implications of using dental amalgam in surgeries, others

Experts have said the use of dental amalgam in surgeries and other procedures in many Nigerian hospitals and clinics has negative effects on human health and the environment. Dental amalgam is a common material used to fill cavities – holes that form in the teeth. The expert said it should not be used in children […]

Experts have said the use of dental amalgam in surgeries and other procedures in many Nigerian hospitals and clinics has negative effects on human health and the environment.

Dental amalgam is a common material used to fill cavities – holes that form in the teeth. The expert said it should not be used in children under the age of 16 years, pregnant women and breast-feeding mothers, among others.

About 10 per cent of the emissions of mercury to the atmosphere are from natural emissions such as volcanic activity, weathering of rock, water body movement, forest fires, and biological processes, 30 per cent is generated by current human activity while  60 per cent is from re-emissions (like evaporation) of mercury already in the environment, mostly as a result of previous human activity.

According to Dr. Tom Aneni, Executive Director, Sustainable Environment Development Initiative (SEDI), dental amalgam contains about 50 percent mercury which is a neurotoxin, a pollutant that is also harmful to human health.

Speaking during a meeting in Benin with the theme, ‘Towards Mercury-Free Dentistry’, Aneni said ending the use of dental amalgam would ensure improved dental health and a cleaner environment for children and women as well as promote disease prevention and protection.

Former Edo State Commissioner for Health, Dr. David Osifo, said research had shown that amalgam contained 50 percent of elemental mercury which was a toxic substance dangerous to the heart, kidney, lungs, cardiovascular and immune system.

Represented by Pastor (Mrs.) Alex Enunwaoyi, Osifor added that “it is particularly dangerous to the vulnerable groups, such as pregnant women, breast-feeding mothers and infants.”

He stressed the need to gradually replace dental amalgam with an alternative that was easily accessible, affordable and sustainable.

He said, “I  support the use of alternative for dental amalgam and  all measures needed to ensure a gradual phase out of amalgam with the use of alternative.”

President of the World Alliance for Mercury-Free Dentistry Charles Brown noted that the campaign to phase down amalgam in Nigeria and the world at large was being moved to the various governments.

Brown also said the organisation was out to ensure mercury-free dentistry across the world, adding that the harmful nature of the material led to the Minamata Declaration in 2013.

The recognition that mercury in dentistry represents a global threat that needed to be tackled through cooperation at the international level led to the international Minamata Convention on mercury.

Dr. Leslie Adogame, Executive Director, SRADev Nigeria, said findings of a study on the state of amalgam use and mercury levels in dental clinics in Nigeria revealed that Abuja dental clinics have the highest emission from the restorative dentistry and waiting area of the clinic, adding that the emission from the surgery room was nine times above the safety limit, which is about 930 per cent increment.

The study was done in some selected dental clinics in Lagos, Ibadan and Abuja. Twelve private dental clinics were used for the study and about 50 per cent of them have high vapour mercury emission.

He said most dental clinics/hospitals and incinerators/medical waste treatment facilities in Nigeria were very high risk environments for mercury vapour emissions and as such pose serious health risk to workers and the general population.

Prof Godwin Toyin Arotiba, a former dean, Faculty of Dental Services, University of Lagos, said everyone is exposed to some degree of adverse health effects depending on the chemical form, concentration, duration and life stage.

He said people are exposed to mercury during dental surgeries through dental amalgam, saying it is a mixture of silver alloy (silver, tin and copper and sometimes zinc, palladium or indium) with mercury.

Prof Arotiba in a paper titled ‘Implementing the Phase Down of Mercury Dental Amalgam: The Road Map to Mercury Free Dentistry in Nigeria’, said reports by experts showed that millions of dentists around the world routinely used dental amalgam as a filling material to repair decayed teeth.

Speaking during a stakeholders meeting on the ‘Development of a National Policy for the Phase Down of Dental Amalgam’, he said in many developing countries, including Nigeria, dental amalgam is the preferred dental restorative material by dental practitioners, because it is very strong, durable, cheap and easy to use.

Therefore, there are tons of mercury in the mouths of Nigerians due to dental amalgam filling.

“When dental amalgam is used, mercury will be released in to the air, water and land, and some of it will eventually be taken up in fish and other living things, including humans,” he said.

He also debunked the idea that dental mercury mostly goes into the mouth of the patient, and more or less stays there until a person dies.

He said dentistry mercury from crematorium and dental clinics gets into the atmosphere and some into solid waste and eventually into fish in the sea, adding that other ways by which people are directly exposed to mercury include hand-mixing of mercury and metal powders, drilling of old amalgam fillings, and extraction of teeth with amalgam.

Others include solid waste disposal bins, slow release of mercury from fillings already in place, emissions from clinic, wastewater system and mercury passing through latex gloves.

Mrs Oluwatoyin Olabanji of the Department of Pollution Control and Environmental Health, Ministry of Environment, said in 2009, UNEP Governing Council established the Intergovernmental Negotiating Committee (INC) to prepare a legally binding international agreement to protect human health and the environment from the adverse effects of mercury.

Stakeholders in the health sector have urged the Federal Government to initiate a coordinated multi-sectoral approach for an effective phase down of the use of dental amalgam in Nigeria.

They also call for the introduction and promotion of alternatives through subsidies as well as immediate update of dental school curricula and training of academic staff of dental schools.