290 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS jority of whom •verc female, were examined by 10 different investigators utilizing chest X-ray (13-22) the reports came from England, France, Ger- many, and the U.S., and conclude unequivocally that no symptoms such as were seen by Bergmann et al., and which could be diagnosed as pulmonary thesaurosis, had been seen in any of the subjects. Notably, however, one ease of a lung disorder called sareoidosis was uncovered in a group of 114 in the U.S. (19), and a second diagnosis of sareoidosis made from a group of 596 in France (20). Because of many diagnostic similarities between sareoidosis and the proposed thesaurosis, many investigators began to have doubts as to whether the two were distinct clinical entities. During the same period that the hairdressers were being surveyed, solitary eases diagnosed as hair spray thesauresis continued to be reported (15, 22- 24). More care appears to have been taken in the diagnosis of some of these later eases (9 in number), sareoidosis having been specifically eliminated in a few of them. So while there is no real evidence to date to link the use of hair sprays to harmful effects on the lungs, the possibility continues to be suggest- ed. It therefore remains the responsibility of industry to continue a program of investigation to settle the issue for once and all. The ultimate question will not be whether thesaurosis or sarcoidosis is the proper diagnosis, but whether these are real, pathological effects on lung tissue as a result of the inhalation of hair sprays. Spray Powders Another cosmetic prodnet which has received attention as a potential inha- lation hazard is tale. The most common toxicological consequence of misuse of this material seems to be accidental aspiration of large quantities which choke off the airways and overwhelm clearance mechanisms (25-27) this occurs most h-equently in young children. Recently, there was a brief uproar surrounding asbestos contamination of the tales being used in cosmetics. The concern which followed the original report arose because certain forms of asbestos have been implicated in the production of cancer in man and animals the insidious nature of the carcino- genesis, in that it takes up to 20 years to manifest itself, xvas the main motiva- tion for the initial reaction. However, upon closer investigation of the prob- lem, it was found that the asbestos forms that are implicated in carcinogene- sis (ehrysotile, amositc, eroeidolite, and anthophylite) were not present in the tales used for cosmetics. Another variety, tremolite, for which there is no evi- dence of carcinogenic hazard, was identified as being present at concentra- tions of less than 5%. Even though carcinogenicity does not seem to be a potential problem, then, as far as the tales are concerned, they should still be subjected to rigorous in- halation testing the same as other aerosolized products.

TESTING FOB INHALATION TOXICITY 291 Propellant Toxicity Possibly the most sensitive problem currently concerning aerosols and their safety is the question of propellant toxicity. An attempt will be made here to briefly recap some of the inhalation toxicity testing that has been done on the propellants, and then to discuss the recent reports which charge that they are unsafe. More than 30 years ago, the Underwriters Laboratories designed inhalation studies using guinea pigs which exposed them to the Freon©* propellants for different lengths of time. The result was a classification, based on the relative inhalation toxicity of these and other materials, that was divided into 8 groups. For purposes of this discussion, the most significant facts to come out of this rating were that Propellant 11 was put into the same category as car- bon dioxide, and that Propellants 12 and 114 were two categories removed from this and classified as less toxic than CO,.. More recent animal studies (28) have reported that when a concentration of 0.08% dichlorodifiuoromethane (Propellant 12) is breathed for 8 hours a day, 5 days a week, for a total of 30 exposures, or when it is breathed continu- ously around the clock for 90 days, some liver damage appears to result in guinea pigs, but not in rats, rabbits, dogs, or monkeys. To put this into per- spective, this is approximately the level of P-12 that would be present in an 8 x 8 x 8-foot bathroom if the entire contents of a standard can of aerosol deo- dorant were discharged in that room (an effort requiring about 4V4 minutes of continuous spraying). Similar experiments (29) using trichlorofiuoromethane (P-11) at 0.1% for a continuous 90-day exposure, or at 1.0% for the 8-hour a day, 30-day regimen, demonstrated no organ changes, and only very minor deviations in certain biochemical parameters in dogs no effects were seen in rats, guinea pigs, or monkeys. Several other investigators support these findings (2, 30-32). It can be concluded, therefore, that these compounds are practically inert with re- gard to toxicity when they are dispensed in an aerosol product in a normal fashion, or even when used to excess, for the purpose for which they were designed. During the late 1960's, however, it began to become apparent that products containing these propellants were being used for something other than their intended purpose. In 1970, Bass (33) reported on this phenomenon increas- ing numbers of young people were inhaling volatile hydrocarbons for the sen- sation of 'q•igh" that they produced. Between 1966 and 1969 a tremendous up- surge in this unique form .of abuse was noted. The mechanism is rather sim- ple: the contents of an aerosol are discharged into a plastic or paper bag, and the volatilized, concentrated propellants are then inhaled. Bass also noted, *E. I. du Pont de Nemours & Co., Inc., Wilmington, Del. 19898.