7.4 Particularly Hazardous Substances

Work with Particularly Hazardous Substances/High Hazard Substances

Additional employee protection will be considered for work with particularly hazardous substances. These include select carcinogens, reproductive toxins and substances that have a high degree of acute toxicity (see Appendix H - Particularly Hazardous Substances). Common chemicals designated as Particularly Hazardous Substances are listed in Lists 1-5 at the end of this document. Pp. 90-93 of the 1995 edition of Prudent Practices provides detailed recommendations for work with particularly hazardous substances. Laboratory supervisors and principal investigators are responsible for assuring that laboratory procedures involving particularly hazardous chemicals have been evaluated for the level of employee protection required. Specific consideration will be given to the need for inclusion of the following:

  1. Planning;
  2. Establishment of a designated area;
  3. Access control
  4. Special precautions such as:
    a. use of containment devices such as fume hoods or glove boxes;
    b. use of personal protective equipment;
    c. isolation of contaminated equipment;
    d. practicing good laboratory hygiene; and
    e. prudent transportation of very toxic chemicals.
  5. Planning for accidents and spills; and
  6. Special storage and waste disposal practices.

Particularly Hazardous Substances

Select carcinogens, reproductive toxins, highly toxic chemicals, and highly reactive chemicals are considered to be high-risk materials and are referred to as “Particularly Hazardous Substances”. 

A. Carcinogens

Carcinogens are chemicals or physical agents that cause cancer or tumor development, typically after repeated or chronic exposure. Their effects may only become evident after a long latency period and may cause no immediate harmful effects.

B. Reproductive Toxins

Reproductive toxins include substances that cause chromosomal damage (mutations) or lethal or malformation effects on fetuses (teratogensis). Many reproductive toxins cause damage after repeated low-level exposures.

C. Highly Toxic Chemicals

Chemicals with a high level of acute toxicity have the ability to cause harmful local and systemic effects after a single exposure. Many of these chemicals may also be characterized as a toxic gas, CDC Select Agent Toxin, or sensitizer.

D. Highly Reactive/Unstable Materials

Highly reactive or unstable materials are those that have the potential to vigorously polymerize, decompose, condense, or become self-reactive under conditions of shock, pressure, temperature, light, or contact with another material. Examples of highly reactive chemicals are explosives, peroxides and peroxide forming chemicals, water-reactives, and pyrophorics.