J. Soc. Cosmet. Chem. 26, 509-522 (1975) ¸ 1975 Society of Cosmetic Che•nists of Great Britain Cough irritation by deodorant sprays E. M. STAAL, W. BREE and P. L. C. A. RIJNBEEK* Synopsis--The causes of RESPIRATORY IRRITATION provoked by DEODORANT SPRAYS have been investigated. For this purpose, the irritant potential of several deodorant spray formulations was determined. The quantitative evaluation of cough stimulation was carried out on a large number of subjects. The various features of the method are discussed in detail. This investigation has shown that the main causes of cough stimulation by deodorant sprays are the antimicrobial agents included in the formulae. INTRODUCTION Cough, triggered by inhalation of an aerosol, is a common mani- festation, very tiresome for the user it should be considered as a technical defect of the aerosol, particularly with aerosols for cosmetic use sprayed towards the body. Cougl• is caused by irritation of the mucous membranes of the nose, throat and respiratory tract. With aerosols, in some circumstances, the sprayed contents may trigger such an irritation. The chemical and pharma- cological bases of this irritation are hardly known. Previous investigation (1, 2, 3, 4, 5, 6) refer mainly to inhalation toxicity in general terms. For this reason, the investigation described here on the causes of cough stimu- lation has been focused on formulation characteristics of aerosols and * Research Laboratory Drogerijen Maatschappij Brabantsestraat 17, Amersfoort, The Nether- lands. 5O9

510 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS particularly to deodorant sprays which are known to induce coughing on some occasions. A method was developed in our laboratories to quantify this effect this so-called Consumer Test Method derived the average value for a numerical rating given by a number of test subjects, with respect to the feature being investigated. The different facets of this test method will be discussed in more detail. The investigation was carried out on 'wet' deodorant sprays without antiperspirant ingredients. Such products are designed to reduce the bac- terial skin flora, thereby preventing the products of bacterial metabolism from giving rise to malodour. Deodorant sprays containing anti-oxidants and odour-absorbers were excluded. Experience had shown that, in spite of similarities in composition, there were wide differences between the irritant properties of commercial sprays. It therefore seemed likely that one or more factors responsible for cough stimulation might be identified. The spray formulae investigated for cough-stimulating activity ranged in composition within the following limits: Fatty substances 0-0.30•o Perfume 0-0.20•o Bactericides 0-0.25•o Solvent 0-50•o Propellant up to 100•o By changing the proportions of the five main components, a number of different deodorant sprays could be prepared, each of which was tested for cough-stimulating potential. No formula without both fatty substances and solvents was studied, as this would have meant that the bactericide would have been sprayed as a dry powder. Fatty substances Perfumes MATERIALS Isopropyl myristate Propylene glycol Isopropyl isostearate Isopropyl palmitate Various