Type IV allergy in the food processing industry: sensitization profiles in bakers,cooks and butchers

Data about the impact of allergic contact dermatitis in food processing occupations are scarce. The objective of this study was to identify the most frequent allergens and sensitization profiles in employees of the food processing industry. The results of patch testing performed in 873 bakers, cooks and butchers suspected of having occupational allergic contact dermatitis from 33 dermatological departments of the Information Network of Departments of Dermatology (IVDK) from 1992 to 1999 were analysed. A final diagnosis of allergic contact dermatitis was made in 213 patients (24.4%). Qualitative and quantitative differences in allergen profiles could be identified. Significantly higher sensitization rates were found in employees in the food processing industry, compared to the total test population, for nickel sulphate (22.4% versus 17.2%, p < 0.0005), thiuram mix (4.9% versus 2.6%, p < 0.0005), formaldehyde (3.5% versus 2.1%, p < 0.005) and Compositae mix (6.2%, p < 0.0005). Significantly lower sensitization rates were found for thimerosal (4.5% versus 6.9%, p < 0.05). For patch testing in food workers, we recommend the standard, the rubber and the Compositae series, as well as patients' own products according to the individual history.     

Can an imidazolidinyl urea‐preserved corticosteroid cream be safely used in individuals hypersensitive to formaldehyde?

A topical corticosteroid preparation on the Swedish market, Flutivate cream, contains a fairly high concentration of formaldehyde (FA). In this study, we have investigated the clinical relevance of contact allergy to FA when treating an allergic eczema with Flutivate cream, containing an FA-releasing preservative. In a randomized, double-blind study, 7 patients hypersensitive to both FA and nickel repeatedly applied Flutivate cream containing FA or Betnovate cream not containing FA to areas of experimentally induced nickel dermatitis. 17 controls allergic to nickel, but not FA, went through the same procedure. In 29 per cent of the FA-allergic individuals, the experimental dermatitis healed when treated with Flutivate cream compared with 71 per cent of the controls (P = 0.04). The conclusion to draw from this study is that an individual hypersensitive to FA should not use the corticosteroid preparation Flutivate cream on dermatitis skin.     

Cost benefit of patch testing with textile finish resins

Eleven years experience of textile finish resin patch testing of suspected textile dermatitis patients revealed 15 cases of allergic textile dermatitis among 428 patients tested. Ten of the 15 patients had a relevant positive patch test to one or more of a limited series of textile finishes; 1 was negative and 4 were not tested with textile finishes. All 15 patients were formaldehyde sensitive. No unexpected, relevant, positive textile finish resin patch test was found. In this study a negative patch test to formaldehyde virtually excluded allergic contact dermatitis from textile finishes.     

More positive patch test reactions with larger test chambers?

Test chambers of various sizes are commercially available for patch testing. Therefore, we asked the question whether the size of patch test chambers may affect allergic patch test reactions. A total of 495 patients were doubletested synchronously with small and large Finn Chambers containing standard preparations of fragrance mix, wool wax alcohols. Kathon CG and formaldehyde, Double tests in 217 patients who had reacted with at least 1 allergic, questionable, or irritant reaction to 1 of these allergens were statistically evaluated. For each of the 4 allergens, a significantly higher number of stronger reactions was seen with the large chambers as compared to the small ones. It is concluded that large test chambers may be useful for detection of weak sensitizations to particular contact allergens.     

A survey of formaldehyde in shampoos and skin creams on the Danish market

To evaluate the exposure of the general population to formaldehyde from the use of cosmetic products, as well as to monitor whether cosmetic products comply with national regulations, 285 shampoos, creams, etc., were analysed for formaldehyde. Identification and determination of formaldehyde was performed by the EEC method for the analysis of formaldehyde in cosmetic products. It was shown that 29.5% of the products investigated contained 0.001%-0.147% total formaldehyde. In 10 of the products (3.5%), total formaldehyde content was > 0.05%. 8 of these products contained > 0.05% free formaldehyde. None of these products was labelled 'contains formaldehyde'. 17 of the products investigated were declared to contain specific formaldehyde-releasers. Formaldehyde could not be detected (detection limit 0.001%) in cosmetic products that were declared to contain Bronidox/Bronopol.     

Contact dermatitis in hairdressers

18 cases of hand dermatitis in hairdressers seen over a 5-year period are reviewed. The diagnoses in these patients are discussed with reference to other studies of hand dermatitis in hairdressers. Contact allergy due to paraphenylenediamine and related hair dyes was the presenting complaint in younger hairdressers, while formaldehyde allergy occurred in those who were older. The prognosis in the former group of workers with respect to continued employment in the trade tended to be poorer than the latter. Follow-up revealed that hand dermatitis often resulted in the worker not continuing to work in the hairdressing trade.     

Contact allergy to the fungicide benomyl?

Benomyl is a widely used fungicide. Contact allergy to benomyl has been reported in a few cases. We describe a group of 62 workers, exposed to benomyl. None had contact dermatitis from benomyl. It appears that benomyl at most is a weak sensitizer. We suggest that earlier-reported allergy may represent cross-reactions and/or that the development of contact allergy to benomyl requires previous exposure to other chemically related pesticides.     

Problems associated with use of the benzyloxymethyl protecting group for histidines Formaldehyde adducts formed during cleavage by hydrogen fluoride 1

The use of N^α-tert.-butyloxycarbonyl-N^π benzyloxymethylhistidine in peptide synthesis resulted in significant levels of several different side products attributable to the generation of formaldehyde during the hydrogen fluoride cleavage reaction. Methylated impurities in a decapeptide were isolated and identified. These methylated impurities were attributed to the use of the benzyloxymethyl protecting group for the histidines, since the impurities did not form when the dinitrophenyl protecting group was used. Also, peptides containing benzyloxymethyl-protected histidines in addition to N-terminal cysteines quantitatively yielded their respective N-terminal thiazolidine derivatives upon isolation from standard hydrogen fluoride cleavage mixtures. Thiazolidine ring formation was circumvented by including in the cleavage reaction a formaldehyde scavenger such as cysteine hydrochloride or resorcinol.     

雨季透析用水消毒方法及时间的改进

目的 保证雨季透析用水质量。方法 传统组采用1％甲醛对反渗机进行消毒；改进组分别对反渗机、贮水罐及供水管道进行分段消毒。比较两组消毒后细菌含量，并探讨时间与细菌含量的关系。结果 改进组反渗机出口水样细菌含量与传统组比较，差异无显著性意义，贮水罐出口与供水管出口水样中细菌含量均显著低于传统组（F＝17．21、11．60，均P＜0．01）；时间与各出口水样细菌含量呈显著正相关（r=0.897、0．886、0．870，均P＜0．01）。结论 雨季透析用水宜用分段消毒法，消毒间隔时间为1个月。