Contact and photocontact sensitivity to sunscreens. Review of a 15-year experience and of the literature.

This review summarizes published and unpublished data of our 15-year experience with sunscreen allergy and photoallergy. From 1981-1996, 402 patients with suspected clinical photosensitivity were patch and photopatch tested with the commercial sunscreens and facial cosmetics that they had used and with chemical UV absorbers, fragrance materials, preservatives, and emollients. 80 patients (20%) (28 men, 52 women) demonstrated allergic and/or photoallergic contact dermatitis to 1 or more UV absorber(s). In 47 patients with photodermatoses or photo-aggravated dermatoses and in 33 subjects with normal photosensitivity, 91 allergic and 84 photoallergic reactions to UV filters were observed. Over the years sunscreens were added to the test series, which since 1989 comprised the following 10 UV absorbers and which induced allergic (a) and photoallergic (pa) reactions (number, type of reaction): 4 UVA absorbers--isopropyldibenzoylmethane (30a/32pa); butyl methoxydibenzoyl-methane (15a/13pa); benzophenone-3 (3a/9pa); benzophenone-4 (0a/0pa); and 6 UVB absorbers--PABA (2a/2pa); octyl dimethyl PABA (1a/2pa); methylbenzylidene camphor (32a/5pa); octyl methoxycinnamate (3a/4pa); isoamyl p-methoxycinnamate (4a/10pa); and phenylbenzimidazole sulfonic acid (1a/7pa). The frequent (photo)sensitization to isopropyldibenzoylmethane was the reason that its production was discontinued in 1993. 47 patients reacted to fragrance materials, 11 to preservatives and 2 to lanolin alcohol. These constituents were contained in the commercial sunscreens and cosmetics that they had used. Continuous revision of the UV absorber photopatch test series was necessary to be closer to the real frequency of exposure and of reported (photo)allergy to newer sunscreens. Clinicians should consider contact and photocontact allergy, especially in patients with photodermatoses and photo-aggravated dermatoses, and they should perform photopatch testing. Once the culprit has been identified, its INCI (International Nomenclature Cosmetic Ingredients) designation should be given to the patient, who must be warned to avoid products containing the (photo)allergen.

Patch test results with serial dilutions of nickel sulfate (with and without detergent), palladium chloride, and nickel and palladium metal plates.

Clinical experience suggests the existence of different degrees of sensitivity in nickel-allergic patients. For quantification of this phenomenon, 462 consecutive patients with previously diagnosed or strongly suspected nickel allergy were tested with serial dilution patch tests with 5 ppm to 5% nickel sulfate in pet. (Ni), and 5 ppm to 1% nickel sulfate in pet. with 1% detergent (Ni/D). Additionally, nickel and palladium metal plates were tested in 103, and cobalt salts, dichromate and palladium chloride (PdCl2) in most patients. 332 patients reacted positively to Ni or Ni/D. The influence of a concomitantly administered detergent was not significant. A significant correlation was found between positive reactions to low concentrations of Ni (or Ni/D), i.e., 0.1% or less (N = 166), and concomitant reactions to nickel metal plates, cobalt salts and PdCl2 and a history of ear piercing with metal intolerance. The clinical relevance of reactions to PdCl2 is at present not clear. A subgroup of nickel-allergic patients with "high sensitivity" can be defined. In future studies further addressing the clinical relevance of high versus low sensitivity, patch testing with 0.01, 0.1, 1.0 and 5% nickel sulfate in pet. is recommended instead of routine tests with 5% only.

Nitro musk.

The detection of nitro musk compounds in breast milk and in human adipose tissue is mainly due to the use of such substances as perfume in detergents from which they enter the sewage and finally the whole freshwater system. Due to their low degradability and a high biological concentration factor, they enter the food chain without the toxicological investigations to date allowing any certain conclusions on the effect of such accumulation in the human organism or on the effect of accumulation in ecological systems.

[Significance of laundry detergent residues from a dermato-toxicological viewpoint]. / Bedeutung von Rückständen von Textilwaschmitteln aus dermatotoxikologischer Sicht.

Detergent residues are often accused to cause efflorescences of the skin. In the present studies different textiles were washed under standardized conditions and the residues analyzed. Textile probes were patch tested for 48 h on seborrheic and sebostatic volunteers. A second series of textiles was given to babies and small children. In all cases no reactions were observed. According to these results and further literature the contribution of detergent residues as a releaser of skin reactions is rather insignificant.

[Phytophotodermatitis caused by plant trimming (edger's rash)]. / Phytophotodermatitis durch "Rasentrimmer" ("Strimmer Rash").

The use of a trimmer for a lawn, which is covered with phototoxic plants such as Heracleum sphondylium and other Umbellifers, can lead to a phytophotodermatitis (trimmer's rash). An erythema of the light exposed skin, following a moderate hyperpigmentation, can cause a focal, vesicular lifting of the upper epidermis, whereby this toxic skin lesion appears similar to an allergic eczema. The best prevention of this harmless but bothersome reaction lies in the use of such an edger only in the evening hours.

[Effect of phototoxic substances on simple biological systems. I. Standardizing the method with furocoumarins]. / Untersuchungen über die Wirkung phototoxischer Substanzen auf einfache biologische Systeme I. Standardisierung der Methode mit Furocumarinen.

As a basis for the investigation of new substances in respect of their photosensitization effects, we established and standardized 3 microbiological test systems, which enabled us to do without animal experiments. Using several furocumarines and various sources of light, we performed a comparative study on the eukaryotes, Chlamydomonas reinhardii (CR) and Candida albicans, and the prokaryote, Bacillus subtilis. We found that, if different light qualities were employed, our test systems also allowed a comparison of different substances by means of half-quantitative evaluation of the inhibiting areolas, which appear after exposure. With regard to the furocumarines, 8- and 5-methoxypsoralene (MOP) had the strongest photosensitizing effect under all test conditions. The remaining furocumarines showed decreasing effectiveness from psoralene to trimethylpsoralene (TMP) and imperatorine; psoralene, however, was slightly more effective in CR than 5-MOP. With the exception of CR, TMP had a stronger effect on the micro-organisms than imperatorine.

Contact allergy to Phacelia spp. (Hydrophyllaceae).

Six persons involved with cultivation trials of Phacelia spp. developed a contact allergy to certain plants of this species. Geranyl(hydro)quinone and related substances, including the geranylhydroquinone geroquinol (INN), which has been introduced as a radioprotective agent, are potent allergens and probably are more often the cause of allergic eczema than is apparent from the literature.