OSHA formerly regulated cellulose under the Agency's generic 8-hour TWA total particulate limit of 15 mg/m3. The ACGIH has a TLV-TWA of 10 mg/m3 (total dust) for this substance. The proposed total particulate PEL was 10 mg/m3 as an 8-hour TWA; however, the final rule retains the Agency's former total particulate limit of 15 mg/m3 and the 5-mg/m3 limit for the respirable fraction. Technical cellulose refers to that portion of the plant cell wall derived exclusively from glucose; it resembles cotton cellulose in its physical and chemical properties (ACGIH 1986/Ex. 1-3, p. 113).
Inhalation of cellulose dust is not irritating or toxic in exposed humans if exposures are properly controlled (Schreiber 1974/Ex. 1-1096). In industry, cellulose dust occurs in combination with other substances, such as quartz dust, wood, cotton, flax, jute, and hemp fibers, and these substances have demonstrated toxicities that are unrelated to their cellulose content (ACGIH 1986/Ex. 1-3, p. 113). NIOSH, the only commenter on cellulose dust, has not conducted an in-depth review of the health effects associated with exposure to this substance (Ex. 8-47, Table N4).
OSHA is retaining its former 8-hour TWA PELs for this substance of 15 mg/m3 (total particulate) and 5 mg/m3 (respirable particulate) for cellulose dust containing less than 1 percent quartz. The Agency concludes that these limits protect exposed workers from the significant risks of eye, skin, and other physical irritation.