Search

The Letterflex urethane photopolymer mixture contains eight components. The curing agent penta erythritol-tetrakis-3 mercaptopropionate and an auxiliary substance present separately, namely 3 mercaptopropionic acid, gave positive reactions in five patients suffering from occupational contact allergic dermatitis. The mixture contains a third substance to which contact sensitization in a single patient has been described in the literature. This substance did not play any role in the patients' dermatitis. The ways in which the workers come into contact with the liquid form of the prepolymer, which is the sensitizing form of the mixture, are described. Safety measures and complete labelling are advised.

In a platemaking procedure differing from Nyloprint and Letterflex, contact sensitizations to 2-hydroxy-ethyl-methacrylate, di- and tetraethylene glycol dimethacrylate and nicotinic acid were found. Preoperational testing of the complete mixture gave a false impression of safety. Preventive measures and enumeration of acrylic substances so far recognized as sensitizers or cross-sensitizers are discussed.

The incidences of sensitisation to Kathon CG are reported for patients routinely tested from 1984 to 1986 in Bari, London, Louvain, Nijmegen, Oulu and San Francisco. For these 3 years, the overall frequency of sensitisation varied for women from 3.3% in Oulu to 0.6% in London and San Francisco and for men from 1.4% in Oulu to 0% in San Francisco. Women were predominantly sensitised, probably by cosmetics, toiletries and domestic cleaners. Occupational sensitisation was much less frequent.

The studies of Monash and Blank (1) demonstrated that, if the skin barrier is removed, water will evaporate from the skin surface at approximately the same rate as from a free water surface. Matoltsy et al. (2) confirmed the finding that water loss of the barrier becomes almost normal in only two or three days after the barrier is re-formed. Total regeneration however requires about two weeks. Matoltsy et al. (2) stated that soon after removal of the stratum corneum a “temporary barrier” with parakeratotic cells is formed, causing water loss to gradually decrease. The “temporary barrier” persists until the regenerating epidermis becomes capable of forming normally keratinized horn cells, the so-called “final barrier.

Der Autor diskutiert die Moglichkeit von Praventivmasnahmen gegen Hautschaden bei der Verarbeitung von Epoxydharzen an Hand der arbeitsdermatologischen Relation zwischen den zu verarbeitenden Stoffen und dem Arbeiter selber. So wird erlautert, wie durch Ersetzen, Mechanisieren, Absondern, durch arbeitshygienische und-methodische Masnahmen, durch Selektion, personliche Hygiene, Instruktion und Kontrolle eine Erniedrigung der Haufigkeit der Hautschaden bei der Epoxydverarbeitung erreicht werden kann.

Methods for investigating contact eczematous patients and for measuring the sensitizing potential of various substances are well known and in general, sufficiently effective. This is not true for irritant dermatitis, or for possible (skin) irritant substances; moreover, cosmetics commonly do not contain acutely harmful ingredients. The use of various instrumental measurements (insensible H2O loss, CO2 release, electrical impedance, sweat rate) as indicators of the irritant potentials of substances is advocated. At the same time it is suggested that the factory physician actively investigate the workers in his factory, since these workers are exposed to known substances in known concentrations and combinations, possibly for extensive periods. This may prove to be part of a new role for him. A cosmetic may be one of several factors increasing impairment and only beyond a certain limit may this result in overt disease. Below that limit the health reserve is only partially depleted. Whether this is harmful to a person depends on other stresses, such as medicaments, work materials, other cosmetics and environmental chemicals. The effect of these must also be quantified. A model of these cumulative stresses and reactions is presented and discussed.

The quick passage of methyl methacrylate at 21 degrees C and 35 degrees C through seven surgeon's glove materials in a diffusion chamber was quantified by gas-chromatographic analysis. Polystyrene-butadiene dissolved in methyl methacrylate, latex and polychlorobutadiene showed reversible expansion, during which material from the samples dissolved. In order to prevent these phenomena from interfering with the analyses, experiments were performed with 4.7 M methyl methacrylate in ethanol. Even then, the time in which methyl methacrylate permeated the membrane was too short for sufficient protection. When using these gloves, the orthopaedic surgeon who is fixing endoprostheses is no doubt occlusively exposed to methyl and other methacrylates, benzoyl peroxide, rubber additives, etc. Of glove materials which are not surgically used, vinyl was inferior to latex, whereas a very thin polyethylene copolymer did not change in methyl methacrylate, showed better resistance to diffusion, but was insufficiently elastic and easily perforated. A better protective material is urgently needed.

An attempt is made to formulate some kind of working hypothesis concerning the pathophysiology, clinical appearance and treatment of irritant contact dermatitis. Acute irritant dermatitis may he caused by one single overwhelming external exposure of comparatively short duration. It is usually accidental and therefore recognized early as cause and effect. Chronic irritant dermatitis may be the result of a too early repetition of one impairing factor (chronic irritant dermatitis ‘traumiteration’ type), but is more commonly the result of the influence of a variety of stimuli, each starting to be active before recovery from the foregoing stimuli has been completed (chronic irritant dermatitis ‘summation’ type). By repetition of the same stimulus, or by a combination of varying stimuli, the degree of impairment surpasses a critical level, in consequence of which a clinical disease (irritant contact dermatitis) ensues. This clinical disease, however, is only ‘the tip of the iceberg’. Such stimuli may be chemical, mechanical and/or climatic. To find out which are the harmful factors requires a detailed case history about the patient's work, habits and hobbies, thus enabling him to avoid as many damaging exposures as is practical, and hence reducing the sum of causative factors. A number of causative factors are enumerated. The article is intended to be a catalyst to promote discussion on this subject.

The effects of topical applications on the living human forearm skin of 3 ml of DMSO 0.09 % JaCI in water solutions of various concentrations during a variety of exposure times were evaluated clinically, and with water vapour loss and impedance measurements. The water vapour loss measurement appeared not to be a sensitive parameter, since it showed only deviations from normal values if there were also clinical signs of irritation, e.g. if the skin is exposed during 15 min to a DMSO solution of 90 % or higher. Impeddance showed some increase after 15-min exposures to 30 % DMSO. In the range of 60 to 99.9 % DMSO, decreases of impedance were found increasing progressively with strength of solution and duration of exposure. Only the longer exposures (3 h to 60 % DMSO) or the higher concentrations (90 % DMSO and over during 15-min exposure) produced clinical signs. Daily repeated short-lasting (5–10 min) exposures to carefully chosen concentrations of DMSO (60, 73 and 86 %revealed that the skin of the volunteer was almost able to resist the lowest concentration. If exposed for 10 min the skin had some difficulty in recovering from the irritating influence of exposures to 60 or 73 % DMSO which took place the preceding day: there is some tendency to a progressive lowering of resistance. With repeated 5-min exposures to 86 % DMSO, this tendency to progressive lowering of resistance is more evident although there is a clear but somewhat incomplete recovery 24 h after each preceding exposure. If the skin is exposed daily to 86 % DMSO for 10 min. the regenerative capacity after the 12th exposure is exhausted. However, after the 17th exposure, extra regenerative forces seem to be mobilized restricting progressively the consequences of every exposure to follow. If the skin is no longer exposed (day 21), recovery is speedier and more complete than that seen after the 5-min exposures to the same strength. We propose calling this ‘adaptation’ or ‘hardening’.

Ephemeral topical contact with hexanediol diacrylate and butanediol diacrylate may cause delayed irritant dermatitis. During 4 years' observation of 20 workers utilizing these substances in the electron beam coating department of a door factory, contact sensitization did not occur. The characteristics of delayed contact irritancy are enumerated. The disease must be distinguished from allergic contact dermatitis, acute irritant dermatitis and cumulative irritant dermatitis.

Thirty-seven substances which may be used in finishing textiles were patch-tested on 66 patients who were suspected of suffering from a textile finish hypersensitivity. Twenty-seven patients reacted positively to one or more of the substances tested (see Table and text). Only seven patients reacted to formaldehyde. This formaldehyde hypersensitivity never occurred alone. In one of these patients the formaldehyde sensitization clearly occurred prior to the outbreak of his textile finish contact eczema. With respect to the other six patients we are inclined to consider the formaldehyde positive patch test likely as a result of group specificity to other textile finishes like dimethylol urea, ethylene urea, urea formaldehyde ether, triazon derivatives, and melamine formaldehyde. In addition to these a number of positive reactions occurred with two compounds derived from stearic acid (substances number 27 and 28) and sporadically also with other compounds.

SUMMARY.— In a series of 4000 patients patch tested in 5 European clinics, 1000 were engaged in domestic work only; they included 281 women with contact dermatitis of the hands. There were no significant differences between the 2 groups as regards age, duration of dermatitis and patch test results. Half of the 281 women had a positive patch test, the responsible allergens in order of rank being balsams, nickel, medicaments, cobalt, rubber, chromate, benzocaine and paraphenylenediamine. But 78% of them were diagnosed as contact dermatitis, 5% atopic and 13% were unclassified. An allergic cause (42%) was as frequent as an irritant (45%) among those with contact dermatitis.