RESUMEN
Synopsis The investigation studied the anti-irritant potential of several substances commonly employed in cosmetic formulations as basic components of the emulsion or as active ingredients, and evaluated the effect of the emulsifier. Five different emulsions were made irritating by addition of croton oil, in sufficient quantity to provoke a clearly adverse reaction in the rabbit, i.e. primary cutaneous irritation index (PII) close to 2. The PII was determined according to the official French methods by applying to symmetrical areas of the back, the irritant base as control and the same base containing the test substance. Fifty-five ingredients were evaluated: gelling agents, plant extracts, molecules defined as healing, anti-inflammatory substances or anaesthesic compounds, etc. The test substances were added to the emulsion at concentrations close to the ones generally found in cosmetics. The qualitative and the quantitative composition of the oil phase was similar for each emulsion. Several gelling agents, thickeners and polymers which notably reduce skin contact with an irritant, gave good results. Some of the usual healing, anti-inflammatory, local anaesthesic compounds gave the expected results. Some ingredients, though well known, were ineffective. The type of emulsifier, by modifying cutaneous penetration and bio-availability of the active ingredients, may play an important role.
RESUMEN
Synopsis Safety tests have been carried out on gums and thickeners, continuing a study involving commonly used cosmetic ingredients (1, 2, 3, 4). The ocular and cutaneous tolerance tests have been conducted on the rabbit following the official French methods (5, 6) but with some complements or modifications (1, 2, 3, 4, 7). The test substances (listed in Table 1) were products from various suppliers and of different types and grades. None of the fifty samples tested provoked pathological lesions of the ocular mucous membrane; nevertheless, corneal irritation was noted with silicates, silica and bentonite, probably due to mechanical effect, when applied at relatively high concentration. The highest score on the primary cutaneous irritancy test (moderately irritant) was that for the gelled volatile hydrocarbon solvents. The repeated application test was continued for 6 weeks: no significant pathological reaction was observed. Only a slight intolerance was noted with the gels of volatile hydrocarbons and isopropyl myristate, but the irritant reactions were significantly reduced compared to those previously observed with the pure oils (1, 2). Consequently, based on these data, it can be concluded that the use of gums and thickeners involved in this publication presents no hazard for the skin.
RESUMEN
Synopsis Safety tests have been carried out on some humectants and moisturizers, continuing a study involving commonly used cosmetic ingredients (1-6). The test substances (listed in Table I) were products from various suppliers and of different types and grades. The ocular and cutaneous tolerance tests have been conducted on animals following the official French methods but with some complements or modifications (28-36). Each compound has been tested as supplied and diluted in water. Pathological lesions of the ocular mucous membrane were provoked by lactic acid at 20 and 10% concentrations. A slight corneal opacity was also noted with ethoxydiglycol and polyamino sugar condensate and a significant irritation with hexylene glycol (non-diluted). In dilutions of 10 or 20%, these substances were non-irritating. Only one product (lactic acid) has given a moderate primary cutaneous irritation (PII = 2.50), when applied undiluted. The indices obtained with the other raw materials correspond to a non-irritating application. With the exception of lactic acid (the study being terminated after 1 week), no significant adverse reaction was macroscopically and histologically observed after daily application (neat) for 6 weeks. Finally, the predictive sensitizing tests (guinea-pig) carried out with two samples of propylene glycol proved to be negative.
RESUMEN
Summary On 26 July 1976, the European Directive relating to cosmetics products added lanolin to the list of substances which cannot be used in these products beyond previously fixed restrictions and conditions (annexe III) with the obligation that labelling bears the wording 'contains lanolin'. The French legislation laid down the term 'Important' with the above condition, thus drawing attention to the presence of one of the most used substances in the cosmetic industry. Without making an account of the comments which have led to that decision, it is admitted that some dermatologists have noticed for 20 years allergic reactions on few persons, after using ointments containing lanolin or lanolin derivatives. Two facts have been noted after a thorough survey of the observed cases: these reactions occurred first with persons suffering from leg ulcers or chronic eczema, and were caused by the free fatty alcohols fraction. On the other hand, literature does not mention any case of allergic reaction on a healthy skin, whether it is human or animal. As we are aware of the importance of the problem and as we have carried out a routine examination of local tolerance. of the main raw materials, already used in cosmetics, for 3 years (1-4), we considered it was of primary importance to study the results obtained from various samples of anhydrous lanolin and its derivatives. The ocular and cutaneous tolerance tests have been made on the rabbit following.
RESUMEN
Summary Different lots of a number of oils used in cosmetics were subjected to different storage times, analysed and their effects on rabbit eye and skin were assessed following the official French methods. The scoring system diverged slightly from the official method and was described in Part I (1). All products were tested pure in the eye test without rinsing and no corneal involvement was found. Slight congestion of the iris and conjuctivae was noted. The products showing the worst (slightly irritant) score were one sample each of avocado oil and ethyl esters of turtle oil. The highest score on the primary cutaneous irritancy test (slightly irritant) was that for the volatile hydrocarbon solvents which also gave an oedematous reaction. On dilution or on open test the reactions were negligible. The repeated application test was continued only for 8 weeks (instead of 90 days) and a histological examination was carried out on treated areas at the end of this period. The oils were applied pure and in aqueous emulsion - 10% or 2% where a severe reaction was observed. Of five samples of sweet-almond oil one showed a high degree of oxidation (peroxide value 35 meq kg(-1)). This sample did not give any significant adverse reaction whereas some irritation and vesicularisation was obtained with a sample of low peroxide value stored under nitrogen. Two of the four samples of avocado oils tested showed severe irritation and vesicle formation after 6 weeks application of the pure oil although no analytical differences were found to correlate with this result. A commercial sample of the unsaponifiable fraction of avocado oil (prepared by molecular distillation) showed severe reactions in the three rabbits treated with the pure oil, the study being terminated after 5 weeks.
RESUMEN
Summary Continuing preceding work (1,2), a series of tests has been carried out on the toxicological evaluation of samples of different fatty esters obtained from several manufacturers. Eye irritation tests and skin irritation and sensitisation tests were carried on the rabbit following the official French methods with minor modifications. When tested pure, nearly all the isopropyl and butyl esters used gave some adverse reactions. Only one sample (out of two tested) of isopropyl stearate appeared to be well tolerated although the primary irritation index on skin was greater than one. The two esters with the greatest adverse skin reactions were isopropyl isostearate and one of two isopropyl linoleates. Ten per cent aqueous dispersion showed considerable diminution of the adverse reactions in the majority of the cases. Considering the results obtained in this paper together with those published previously (1) being twenty-seven samples covering fifteen different fatty esters, the worse reactions were obtained with the C(8), C(12), C(14) saturated together with the oleate and linoleate esters. Isopropyl palmitate, stearyl heptonate and arachidyl propionate were the best tolerated as pure materials. Other adverse reactions were obtained with the isopropyl, butyl and octyl stearates and isostearates (except for one of two isopropyl stearates) and from these results appears that the alcohol moiety plays little part in irritation when compared with the fatty acid chain. Examination of peroxy values indicates that these have a significant adverse effect for oleates and linoleates.