Dental Amalgam and Mercury Spillages
Tags: Dental Amalgam, Mercury Spillage, Segregation
What is amalgam?
Amalgam is a filling material used by dentists across the world for almost 150 years. It was first documented in a Tang Dynasty medical text book in China written by Su Kung in 659. It was in the 1800’s that dental amalgam became the material of choice to restore cavities caused by decay.
Amalgam is a mixture of powdered metal alloys containing tin, silver, zinc and copper. 50% of amalgam is made up of mercury.
Amalgam is known as one of the best materials to fill a tooth cavity as it is long lasting, less likely to break and less expensive to place.
There is also a negative side to dental amalgam and it is thought there could be a potential risk of slow releasing mercury vapours from the dental filling.
In 2008, Denmark, Sweden and Norway placed a ban on the use of dental amalgam for health and environmental reasons.
Dentists in Denmark are only allowed to use amalgam for permanent molar teeth
What is mercury?
Mercury is a shiny silver metal which is a liquid at room temperature. It is a naturally occurring element found in rocks, soil and water.
Mercury is traditionally used in thermometers and some electrical switches. Unlike other metals mercury is a poor conductor of heat.
Mercury is highly toxic and must be handled with care at all times. The reason being is that mercury can be absorbed through the skin and mucous membranes of the body. Mercury vapours can also be inhaled. Mercury can poison causing damage to the central nervous system, kidneys and liver.
Dental practice smust handle amalgam capsules with care and should comply with current legislation.
Hazardous Waste Legislation
The dental practice has a legal obligation to comply with the following legislation:
- EU Waste Framework Directive 2011,
- The Controlled Waste Regulations 2012
- The Environmental Protection Act 1990
- Duty of Care Regulations
- The Carriage of Dangerous Goods Regulations.
The dental team must be trained in the correct:
Handling of hazardous waste
- Segregation – Please note that amalgam contaminated single use matrix bands should be disposed of in the waste amalgam pot, not the sharps bin
Controlled hazardous waste must be not be deposited unlawfully – this means that amalgam waste must not go down the sinks or toilet in the practice. And must not be placed in the orange clinical waste bags.
Correct segregation of dental amalgam
In 2005 it came into effect that all suction units should be fitted with an amalgam separator to collect the mercury hazardous waste.
The amalgam separator should meet the BS ISO criteria and CE marked to meet CQC Regulation 15 Premises and Equipment
Teeth with amalgam fillings
Extracted teeth containing amalgam fillings should be segregated into a separate container. This container is usually supplied under contract from the company you use for hazardous waste.
Teeth – HTM 01 07 Safe Management of healthcare waste
19 As the disposal of teeth from dental practices is unlikely to cause offence, dental practitioners may treat this as non-autonomical infectious waste. It is common practice for non-amalgam teeth and spicules to be placed in the yellow-lidded sharps receptacle. Dental practitioners must ensure that all waste is treated appropriately, and teeth containing amalgam should be segregated and sent for appropriate recovery/disposal.
5.57 Amalgam – white containers
Amalgam waste consists of amalgam in any form and includes all other materials contaminated with amalgam. Amalgam waste should be placed in rigid white receptacles with a mercury suppressant.
Amalgam waste should be sent to suitably licensed or permitted waste management facilities where the waste undergoes a mercury recovery process prior to final disposal
An amalgam spillage kit should be used in the event of a spillage. Never use a vacuum cleaner, brush or mop to clean up the spillage.
You should never:
- Never use a vacuum cleaner, brush or mop to clean up the spillage.
- Never pour mercury or amalgam waste down the drain or toilets
- Never wash mercury contaminated clothes in a washing machine
- Never continue wearing shoes that have been contaminated with mercury
- Open a window to ventilate the area
- Leave the room until you begin to clean up the spillage
- Advise others not to enter the room until after the clean up
- Locate the amalgam spillage kit
Procedure for spillage (also check the manufacturer’s instructions before use)
- Put on the PPE which is provided in the kit
- Using the scoop collect the amalgam or mercury waste
- If it is mercury droplets use the syringe to pick up as many globules as you can. Then place the full syringe in the waste container (provided in the kit)
- Open the container which contains calcium hydroxide and sulphur
- Tip out onto the spillage area, close the centre of the spillage
- Using the scoop mix the powders with the spilt amalgam or mercury (which you could not pick up)
- The powder may start to go grey as the mercury is absorbed.
- Using the brush – brush the contaminated powder into the scoop and place in the waste container
- Close the lid on the waste container or sealable bag
- Dispose of the PPE in the waste container or sealable bag
- Label the waste container or bag with ‘hazardous waste sign’
- Contact the licensed waste carrier company you use to remove the hazardous waste
- Perform hand hygiene
- Order a new spillage kit immediately or check the manufacturer instructions as to what the spillage protocol is.
It may be necessary to undergo a mercury screening test if there has been a significant exposure to mercury. Contact your local occupational health team to seek advice.
Isopharm offers a wide range of spillage kits, including a kit for mercury spillages.
By Stacey Firman