A carcinogen is any substance or agent that is capable of causing cancer the abnormal or uncontrolled growth of new cells in any part of the body in humans or animals. Carcinogens are chronic toxins with long latency periods that can cause damage after repeated or long duration exposures and often do not have immediate apparent harmful effects.

The OSHA Lab Standard defines a Select Carcinogen as any substance which meets one of the following criteria:

(i) It is regulated by OSHA as a carcinogen; or

(ii) It is listed under the category, "known to be carcinogens," in the Annual Report on Carcinogens published by the National Toxicology Program (NTP) (latest edition); or

(iii) It is listed under Group 1 ("carcinogenic to humans") by the International Agency for Research on Cancer Monographs (IARC) (latest editions); or

(iv) It is listed in either Group 2A or 2B by IARC or under the category, "reasonably anticipated to be carcinogens" by NTP, and causes statistically significant tumor incidence in experimental animals in accordance with any of the following criteria:

(A) After inhalation exposure of 6-7 hours per day, 5 days per week, for a significant portion of a lifetime to dosages of less than 10 mg/m(3);

(B) After repeated skin application of less than 300 (mg/kg of body weight) per week; or

(C) After oral dosages of less than 50 mg/kg of body weight per day.

To find out if a chemical is a carcinogen, California's Proposition 65 lists all chemicals known to cause cancer or reproductive toxicity.

When working with hazardous materials in the laboratory be sure to:

• Wear proper protective equipment including gloves, goggles and a lab coat that covers street clothes
• Gloves should be selected based on the properties of the chemicals in use
• Do not eat, drink, chew gum or apply cosmetics in the area toxic chemicals are being used
• Keep accurate records of amounts of these substances used
• Have a plan, proper equipment and materials ready to minimize exposure if an accident is to occur
• Procedure should be done with the minimum amount of material needed to complete the task
• All procedures should take place in a "controlled area" that is clearly labeled warning and restrictive access sign
• Whenever possible, fume hoods, glove boxes and isolation cabinets should be used, if these are not feasible, proper respiratory protection must be worn
• All work surfaces should be easily cleanable and covered in an impervious or disposable material
• Wash hands, arms and decontaminate work surface and equipment thoroughly when done with the procedure
• Protective apparel worn while working with toxic materials should not be worn outside the laboratory
• Ensure that containers of contaminated waste are transferred from controlled area in a secondary container to avoid further contamination