Aerodynamic diameter measurement of cellulose acetate fibers from cigarette filters: what is the potential for human exposure?
Aerodynamic diameter is a major determinant of particle and fiber deposition and toxicity in the respiratory tract. To characterize cellulose acetate fibers released from the filter end of cigarettes puffed under conditions approximating smoking, we designed multistage impactors to determine the aerodynamic diameters of large fibers with circumscribed diameters between 20 and 35 microm and aspect ratios ranging from subfiber ratios up to 40. This range of diameters encompasses all of the cellulose acetate fiber sizes that are commercially manufactured. When commercially available cigarettes with filters made from acetate fibers in this circumscribed diameter range were puffed directly into the impactor, on average 10 fibers/cigarette were released and their aerodynamic diameters were determined. In our studies, we found that the aerodynamic diameters of the cellulose acetate fibers were always greater than 23 microm. Using standard lung deposition models, we concluded that the fibers are nonrespirable with a very low probability of penetration to the distal lung. Our findings, which demonstrate release of only a small number of these large fibers with an extremely low likelihood of reaching the distal lung, indicate that these fibers are not a risk for human lung disease.
Collazo
Humberto
H
Eastman Chemical Co., Kingsport, Tennessee 37660, USA. collazo@eastman.com
Crow
W Andrew
WA
Gardner
Lonnie
L
Phillips
Brenda L
BL
Dyer
W Mills
WM
Marple
Virgil A
VA
Utell
Mark J
MJ
D000392:Air Movements; D001672:Biocompatible Materials / Q000032:analysis*; D002482:Cellulose / Q000031:analogs & derivatives* / Q000032:analysis*; D005374:Filtration; D006801:Humans; D019570:Inhalation Exposure; D008422:Materials Testing; D010316:Particle Size; D018570:Risk Assessment; D012907:Smoking
D001672:Biocompatible Materials; C005062:acetylcellulose; D002482:Cellulose