THE PRESENT POSITION REGARDING TOXICOLOGY OF HAIR SPRAYS 47 obvious question is this: Are the particles of hair sprays of respirable size ? Obviously with an unstandardized product of this sort there are bound to be wide variations between different brands involving different compositions and incorporating different valves variations also from one dispenser to another of the same brand, in spray from the same dispenser when it is new or almost empty, in particles inhaled immediately or after aging in the atmosphere (that is, permitting the evaporation of volatile material). In any of these circumstances, is there a proportion of particles of a size that can penetrate to the lower reaches of the bronchial tree or the alveoli of the lung ? Here we encounter a serious discrepancy. The FDA workers [Draize et al, Proc. Sci. Sect. Toilet Goods Assoc. 31 28 (1959)] reported that in 6 types of unimpinged hair spray, 65% by weight of the particles were below 10s in diameter and 35•o below 7•, with less than 10% variation between types from which it may be inferred that a con- siderable part of each spray was respirable. Brunner and his colleagues' analyses of 3 "current .... typical" commercial hair sprays indicate that, after aging, particles below 10 • constituted less than 0.5% of the total 50% were 35• or more in diameter. If this is so, there can be no problem since such particles are incapable of reaching the lower respiratory tract. Unfortu- nately, British experience accords with that of Draize et al in indicating that a substantial proportion of hair spray particles are of respirable size. Be that as it may, this discussion does underline the importance of making sure, when animal inhalation experiments are carried out, that the quantity of hairspray polymer actually inhaled into the lungs, and retained there, is known. Because most of the material is filtered out in the labyrinthine tortuosities of the animal nose, or smartly elevated up the ciliary "escalator", quantitative measurements of retention in the lung are essential. Since such measurements were not carried out, it is difficult to assess the significance of negative findings in the experiments performed by Draize et al (loc. cit.) on rabbits, and by Calandra and Kay [Proc. Sci. Sect. Toilet Goods Assoc. 30 41 (1958)] on guineapigs, involving repeated and prolonged exposure to hairspray aerosols. Brunner et al have now perpetrated the same error in 90-day ex- posures in rats and guineapigs. They make amends, however, by introducing saline suspensions of evaporated hair spray directly into the lungs of guinea- pigs through an opening in the trachea. This approach, carried out every day for 10 days, merely induced non-specific inflammatory reactions, whether polymer (polyvinylpyrrolidone) or saline was used. It can be argued, however, that direct instillation of this sort in no way reproduces the inhala- tion of hair spray particles. Despite its success with siliceous dusts, the technique can hardly ensure that water-soluble polymeric material pene- trates to the bronchioles and beyond, still less that any remains there. We are left then with a number of uncertainties. One way of deciding

48 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS whether or not there is a public health hazard is the epidemiological approach by studying hairdressers and "beauticians" working in salons. Surveys of this sort are in progress in the U.S.A., in Great Britain and elsewhere. The Editorial referred to above [J. Am. Med. Assoc. 184 888 (1963)• speaks of "thousands" who have been examined and thousands more who are being examined. A preliminary report on 113 heavily exposed hairdressers was negative [McNall et al, Proc. Intern. Congr. Bronchoesophagology, Kyoto 7 140 (1958) quoted from Brunner et al, loc. cit.•. .4 British Survey John [Med. Off. 109 399 (1963)• has published the results of a pilot radio- graphic survey carried out in Oxford. It covered hairdressers, 128 women and 18 men, from 14 salons. The majority had at least two years' history of exposure to hair spray, the mean periods being 3.4 yr for women and 5.4 yr for men their mean ages were 20 and 30 respectively. No abnormalities of any sort were encountered. The survey cannot be said to rule out the possibility of some hazard arising from hair sprays. Its scope was limited the age of the hairdressers was well below that of patients reported to have thesaurosis, where the average age was about 40 yr finally, the possibility of individual susceptibility cannot be excluded by a survey of this sort. Publicity in Great Britain A press release by the Hairdressers' Publicity Group ["News about Hair", 10th July 1963• claims that reassuring results have been obtained in surveys conducted in the British hairdressing industry by the Medical Re- search Council to investigate the possible dangers to hairdressers and their customers of inhaling hair lacquers. The investigation was conducted on hairdressers who had been exposed to sprays based on polyvinylpyrollidone and on shellac, and also on men's hairdressers who had not been exposed to hair lacquer sprays. Of 755 people examined, no abnormal X-ray appearances which could be attributed to the inhalation of hair sprays were found. A woman hairdresser, not included in the X-ray survey, was referred to the M.R.C. workers on account of lung disease. To quote the report: "Comprehensive investigations indicate that the most likely cause of' her lung condition was the inhalation of a shellac-based hair lacquer for a total period of 13 years. This one case prevents us from saying that the use of hair sprays is completely harmless. It is possible, however, that only hypersensitive people will react by developing a lung disease, and the evidence from