Gypsum Waste

Gypsum waste disposal

As healthcare waste producers, dental practice owners have a legal duty of care to ensure waste is managed and disposed of responsibly, ensuring hazardous waste does not cause pollution to the environment of harm to human health.

In accordance with the Environment Permitting Regulations 2010 (England and Wales), dental study models which contain gypsum has been banned from entering normal landfill in England from 2009 and must go into a separate cell for high sulphate waste.

Appropriate disposal

If gypsum is mixed with other biodegradable waste in a normal landfill, then hydrogen sulphide gas can be released. Hydrogen sulphide is a toxic, colourless, flammable gas with a very distinct foul odour – rotten eggs. Exposure to hydrogen sulphide can lead to some adverse health effects, such as breathing difficulties, discolouration of the skin and eye irritation. So appropriate methods of disposal should be followed.

The two main disposal options for gypsum waste are:

• Gypsum recycling
• Landfill in a separate cell of a landfill that has been set aside for such waste

Extracted guidance from 07-01: Safe management of healthcare waste

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Gypsum-rich wastes are likely to be produced as:

• Plaster casts and related materials in accident and emergency departments, fracture clinics, and perhaps veterinary surgeries;
• Plaster models in dental practices and similar units in hospitals. They may also be produced by chiropodists/podiatrists

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Gypsum (calcium sulphate) will generate hydrogen sulphide gas from microbial action if it enters a normal mixed landfill. The two main disposal options for such wastes are: a. gypsum recycling; or

• b. landfill in a separate cell of a landfill that has been set aside for such waste.

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The vast majority of plaster casts and models are not infectious and must not be placed in the clinical waste stream. Gypsum plaster casts should not be placed in the offensive waste stream either. These should be segregated as a specific 18 01 04 gypsum waste stream.

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Where a producer can demonstrate that they have segregated and separately disposed of most of the gypsum in this manner, the presence of a small number of genuinely infectious plaster items may also need to be segregated for separate disposal. In any event, it should be ensured that this material does not end up directly or indirectly in landfill

Segregation of non-contaminated models

Dental study models which have not been contaminated should be segregated and placed in a separate bin which is provided by your hazardous waste contractor. This will have a white label and should say gypsum segregation box. The hazardous waste contractor will dispose of any full gypsum boxes and will replace with an empty box.

Contaminated models

Most dental study models will not be contaminated or infectious. In the rare instance that a dental study model is contaminated, then it should be disposed of as hazardous waste. This will then be sent for incineration.

Induction training

All staff involved in healthcare waste handling must be trained and fully informed of the practice procedures.

The practice should have procedures in the following areas:

• Personal protective equipment
• Segregation, handling, storage and collection of healthcare waste
• Safe and appropriate cleaning
• Handling waste bags
• Checking the storage containers are sealed correctly – especially sharps bin lid
• Accidents and spillages
• Understanding marks and labels
• Emergency procedures

Seek advice

In order to adhere to the correct regulations in waste management, practices that are unsure of the correct procedure for the management of waste disposal must seek advice from a waste management expert to ensure compliance with regulations.