PARAFFIN WAX FUME

OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.

CAS: 8002-74-2; Chemical Formula: C_nH_2n+2

OSHA previously had no limit for paraffin wax fume and proposed establishing an 8-hour TWA limit of 2 mg/m³; NIOSH (Ex. 8-47, Table N1) concurred with this proposal. The final rule establishes this limit, which is the same as the limit recommended by the ACGIH. Paraffin is a white or slightly yellow, odorless solid that is derived from petroleum.

Paraffin is considered nontoxic in its solid state, but fume generated when it is in the molten state may cause discomfort and nausea (Queries and Minor Notes, JAMA 1938/ Ex. 1-308). In the most recent report of industrial exposure effects, paraffin fume is reported to cause no discomfort in most cases when the concentration is maintained at or below 2 mg/m³, although one instance of mild discomfort was reported at concentrations between 0.6 and 1 mg/m³ (Massachusetts Division of Occupational Hygiene 1970, as cited in ACGIH 1986/Ex. 1-3, p. 455).

Dr. William Zeiler, President of the College of American Pathologists (Ex. 3-976), objected to OSHA’s inclusion of paraffin wax fume in the final rule, stating that the scientific basis for the limit was lacking. Specifically, Dr. Zeiler commented that the JAMA article (1938/Ex. 1-308) reported “vague and nonspecific” symptoms and that the reference from the Massachusetts Division of Occupational Hygiene was unpublished. He also reported that a literature search dating back to 1965 produced no references on the toxicology of paraffin wax fume. Dr. Zeiler expressed concern that, if a final limit is promulgated for paraffin wax fume, “nonspecific complaints about the workplace environment may implicate this substance as the cause” (Ex. 3-976).

OSHA is aware that the dose-response data for paraffin wax fume are dated; nevertheless, OSHA finds it notable that two different sources (cited by ACGIH 1986/Ex. 1-3, p. 455) report acute adverse effects associated with the use of molten paraffin. OSHA also believes that promulgation of a PEL for paraffin wax fume will present little problem for pathology laboratories, since Dr. Zeiler commented that most clinical laboratories already comply with the ACGIH TLVs and that the services of certified industrial hygienists are used when new laboratories are designed or old ones are remodeled. OSHA is more concerned about workplaces in which paraffin is used in large quantities, such as the food industry, and a greater degree of exposure control is needed. To protect employees in these industries from experiencing acute adverse effects, such as discomfort and nausea, OSHA believes that a PEL for paraffin wax fume is necessary. The Agency has determined that the adverse effects associated with excessive exposure to paraffin wax fume constitute material impairments of health. The limit of 2 mg/m³ has been shown to be effective in reducing this risk (ACGIH 1986/Ex. 1-3, p. 455); therefore, OSHA is establishing this limit for paraffin wax fume.