Assessment and management of chemical exposure in the Mohs laboratory

The correct handling, storage, and disposal of chemicals used in the processing of tissue for Mohs micrographic surgery are essential.

To identify the chemicals involved in the preparation of Mohs frozen sections and assess the associated occupational health risks. To quantify exposure levels of hazardous chemicals and ensure that they are minimized.

A risk assessment form was completed for each chemical. Atmospheric sampling was performed at our previous laboratory for formaldehyde and volatile organic compounds. These data were used in the design of our new facility, where testing was repeated.

Twenty-five chemicals were identified. Ten were classified as hazardous substances, 10 were flammable, six had specific disposal requirements, four were potential carcinogens, and three were potential teratogens. Formaldehyde readings at our previous laboratory were up to eight times the national exposure standard. Testing at the new laboratory produced levels well below the exposure standards.

Chemical exposure within the Mohs laboratory can present a significant occupational hazard. Acutely toxic and potentially carcinogenic formaldehyde was found at high levels in a relatively standard laboratory configuration. A laboratory can be designed with a combination of physical environment and operational protocols that minimizes hazards and creates a safe working environment.