Skin protection in the food industry.

In food occupations, like in many other skin risk occupations, the regular use of personal protection equipment, i.e. of skin protection ointments and protective gloves, is recommended as well as regular skin care for the prevention of occupational hand dermatitis. We investigated the uptake and maintenance of different prevention strategies (instructions for skin protection and skin care, prevocational skin hardening with UV light) in food occupations and their efficacy in the primary prevention of vocationally caused hand dermatitis. We could show that the acceptance and regular use of skin protection and care measures could be significantly increased by theoretical and practical instructions in food industry trainees. The highest acceptance was seen with skin protection ointment (100%) and skin care (90%). Protective gloves (43.3%) were used to a lesser extent. The hand dermatitis point prevalence in the groups after 6 months was 13.3% (skin protection), 19.4% (UV hardening) and 29.1% (controls). These clinical trends were supported by statistically significant differences in the basal TEWL values. Adequate skin protection and regular skin care seem to be promising for the prevention of occupationally caused hand dermatitis. The experimental approach using UV hardening prevocationally did not fulfil the expectations.

Quantitative patch and repeated open application testing in methyldibromo glutaronitrile-sensitive patients.

Contact allergy to methyldibromo glutaronitrile (MDBGN), often combined with phenoxyethanol (PE) (e.g., Euxyl K 400), increased throughout the 1990s in Europe. Consequently, in 2003, the European Commission banned its use in leave-on products, where its use concentration was considered too high and the non-sensitizing use concentration as yet unknown. The 2 objectives of the study are (a) to find a maximum non-eliciting concentration in a leave-on product in MDBGN/PE-sensitized patients, which could possibly also be considered safe regarding induction and (b) to find the best patch test concentration for MDBGN. We, therefore, performed a use-related test (ROAT) in patients sensitized to MDBGN/PE (n = 39) with 3 concentrations of MDBGN/PE (50, 100 and 250 p.p.m. MDBGN, respectively). A subset of these patients (n = 24) was later patch-tested with various concentrations (0.1, 0.2, 0.3 and 0.5% MDBGN, respectively). 15 patients (38%, 95% confidence interval (CI) = 23-55%) had a negative and 24 (62%; 95% CI = 45-77%) a positive overall repeated open application test (ROAT) result. 13 reacted to the lowest (50 p.p.m.), 8 to the middle (100 p.p.m.) and 3 to the highest concentration (250 p.p.m.) only. In those 13 reacting to the lowest ROAT concentration, dermatitis developed within a few days (1-7). The strength of the initial and the confirmatory patch test result, respectively, and the outcome of the ROAT were positively associated. Of the 24 patients with a use and confirmatory patch test, 15 reacted to 0.1% MDBGN, 16 to 0.2%, 17 to 0.3% and 22 to 0.5%. With the patch test concentration of 0.5%, the number of ROAT-negative patients but patch-test-positive patients increases considerably, particularly due to + reactions. A maximum sensitivity of 94% (95% CI = 70-100%) is reached with a patch test concentration of 0.2%, and is not further improved by increasing the concentration. However, the specificity decreases dramatically from 88 (95% CI = 47-100%) with 0.2% to a mere 12.5% (95% CI = 0-53%) with 0.5%. It can be concluded (a) that for MDBGN 0.2% is very likely the best patch test concentration and (b) that 50 p.p.m. in a leave-on product can elicit contact dermatitis in sensitized persons. We were, therefore, unable to find a safe, still microbicidal, concentration for leave-on products. By contrast, with other contact allergens, dose-response use tests may be able to identify a non-eliciting concentration, which could give valuable clues to a non-inducing (i.e., safe) concentration in products.

Additive impairment of the barrier function and irritation by biogenic amines and sodium lauryl sulphate: a controlled in vivo tandem irritation study.

Biogenic amines are potential irritants e.g. in fish-, meat-, milk- and egg-processing professions like cooks, butchers and bakers. The aim of this study was to test the irritative and barrier-disrupting properties of the biogenic amines ammonium hydroxide (AM), dimethylamine (DMA) and trimethylamine (TMA). A repeated sequential irritation of 30 min twice per day was performed over a total of 4 days (tandem repeated irritation test) on the back of 20 healthy volunteers of both sexes with AM, DMA, TMA and sodium lauryl sulphate (SLS). The epidermal barrier function was assessed with a Tewameter TM 210, stratum corneum surface pH was measured with a Skin-pH-Meter 900, inflammation was assessed with a Chromameter CR-300 on the a* axis for redness and a visual score was recorded. All tested biogenic amines (AM, DMA and TMA) induced a barrier disruption and a pH increase paralleled with a 1-day-delayed onset of inflammatory signs. These effects were further enhanced and accelerated by a sequential application of SLS together with the biogenic amines, and inflammation occurred earlier than with the single compounds. Acetic acid (AA) in contrast did only show mild barrier disruption and no significant inflammatory signs. Our system allowed a ranking of the different compounds in their irritative potential in the tandem irritation with SLS: SLS > NaOH > TMA > AA > AM > DMA. The results are suggestive that in the food-processing industry the simultaneous contact with biogenic amines and harmful detergents like SLS should be minimized.

Fruit acids and sodium hydroxide in the food industry and their combined effect with sodium lauryl sulphate: controlled in vivo tandem irritation study.

BACKGROUND: Cutaneous exposure to a variety of irritants has been extensively studied in recent years. Nevertheless, knowledge of the induction of irritant dermatitis, especially by mild irritants at low doses and for a short duration of exposure, is still incomplete. OBJECTIVES: To quantify the irritant effects and barrier disruption properties of ascorbic acid (ASC), acetic acid (ACA) and sodium hydroxide (NaOH), particularly in combination with an anionic detergent, sodium lauryl sulphate (SLS). METHODS: In a tandem repeated irritation test, the irritants were applied for 30 min twice daily for 4 days to the skin of the mid-back of 19 healthy volunteers of both sexes. We used bioengineering techniques for measurement of transepidermal water loss (TEWL) and skin colour reflectance, as well as visual scoring. RESULTS: Repeated application of ASC and ACA caused a moderate increase in TEWL and erythema. The sequential application of ASC or ACA and SLS enhanced these effects. NaOH induced a strong reaction when applied both occlusively and nonocclusively as well as in combination with SLS, with an early onset of the inflammatory signs, leading to discontinuation of the application on the third day in most of the test fields. Notably, the irritant effect of NaOH was not as marked when applied sequentially with SLS. CONCLUSIONS: Our results demonstrate that concurrent application of an anionic detergent and a mild acidic irritant can lead to disruption of the barrier function which, although not additive, is still considerable. The combined application of SLS and mild acids does not prevent SLS-induced irritation. Furthermore, we showed that NaOH in low concentrations may also act as a potent irritant but that its effect is not enhanced by SLS. The necessity of adequate skin protection and reduction of contact with substances that are potentially barrier disruptive and irritant, e.g. in the food industry, is emphasized, not only when handling detergents, but also when processing food products.

The atopy patch test -- reproducibility and comparison of different evaluation methods.

BACKGROUND: There is still a lack of standardization of the atopy patch test (APT) in test procedures and evaluation methods. Our aim was to examine the reproducibility of APT results and to compare visual evaluation to chromametry and laser Doppler imaging. METHODS: Fifty-two volunteers with atopic eczema/dermatitis syndrome (AEDS) were included. The APT was performed on tape-stripped and unstripped test fields on their backs using cat dander, house dust mite and grass pollen allergens from two different suppliers. Responders were re-tested 4-12 weeks later with the same allergens on their forearms. RESULTS: Using Allergopharma allergens, 14 (26.9%) volunteers showed one or more positive reactions. The reproducibility rate was 56.3%. The Erlangen atopy score in APT-positive and negative volunteers was 19 +/- 6 vs 15 +/- 6. The test agreement in volunteers tested with both allergens, from Allergopharma and Stallergènes, was poor. Correlation of the results between the three evaluation methods was significant (P < or = 0.001). CONCLUSIONS: The low reproducibility rate of APT results and the poor inter-test-agreement using allergens from different suppliers show that much work remains to make the APT a reliable tool in identifying relevant aeroallergens that lead to flare ups of AEDS. Compared to chromametry and laser Doppler imaging, visual scoring was superior in differentiation between irritative and allergic reactions.

Occupational hand dermatitis in food industry apprentices: results of a 3-year follow-up cohort study.

OBJECTIVE: The aim of this prospective follow-up study was to quantify the impact of hand dermatitis (HD) in bakers, confectioners and bakery shop assistants, and to investigate related risk factors. METHOD: Bakers', confectioners' and bakery-shop assistants were included in a prospective follow-up study in the region of East Thuringia starting in August 1996. At the beginning of their vocational training 91 apprentices were interviewed and examined in a standardised way. Follow-up examinations and interviews were done after 6 months (n = 79), 12 months (n = 63) and at the end of the training (n = 69) after 36 months. RESULTS: In their case histories 3.3% (n = 3) of the apprentices reported previous HD in childhood and adolescence. The first assessment after 2 to 4 weeks of vocational training revealed HD in 17.5% (n = 16) of the individuals. At the follow-up examination after 6 months, point prevalence of HD was 29.1% (n = 23), after 12 months 27.0% (n = 17) and after 36 months 27.5% (n = 19). Mild to moderate irritant contact dermatitis was the most frequent finding. Finally, an atopic skin diathesis (> 10 points, "atopy score") (OR = 4.89; CI 95% 1.15-20.79), previous HD (OR = 41.1; CI 95% 4.99-339.13) as well as flexural dermatitis (OR = 6.8; CI 95% 1.72-27.22) proved to be predictive factors for the development of HD. No association was found to respiratory atopy (OR = 1.29; CI 95% 0.35-4.7) and metal sensitisation (OR = 1.1; CI 95% 0.29-4.35). Exogenous irritant factors did not show a strong association towards a risk increase. Wet work in general, as well as distinct occupational tasks showed only a tendency for being a risk factor for HD. However, leisure time activities, especially house building and rebuilding (OR = 5.4; CI 95% 1.05-27.81), were associated with an elevated risk. CONCLUSIONS: Endogenous and exogenous factors contribute to the development of HD in bakers' and confectioners' apprentices.

The prevention of occupational hand dermatitis in bakers, confectioners and employees in the catering trades. Preliminary results of a skin prevention program.

Occupational skin diseases (OSD) are among the most frequent occupational diseases (OD). Compared to other occupations, bakers, confectioners and employees in the catering trades are at a high risk of developing OSD. In January 1999, the interdisciplinary Skin Disease Prevention Program in the Baking, Hotel and Catering Industries (SDPP) conducted by the Department of Dermatology and Allergology at the Friedrich Schiller University, Jena, in cooperation with the Research Center for Applied System Safety and Industrial Medicine, Erfurt, and the technical experts at the Social Insurance for the Food Industry and Related Professions (Berufsgenossenschaft für Nahrungsmittel und Gaststätten--(BGN)), Erfurt, was initiated. Following detailed analysis of the occupational exposure of the employees and their personal occupational disease history, the patients' diagnosis and therapy was re-evaluated and supplemented if necessary. Individual skin care and protection regimes were demonstrated and practically trained. Skin care and protection products were supplied. Skin-care and protection seminars were offered to volunteering participants. From January to December 1999, 29 affected employees were examined in the OSD clinic. 22 employees (76%) suffered from irritant contact dermatitis. The follow-up data of 11 employees are available. In 8 employees (73%), the skin disease improved or disappeared. Moreover, in 1 employee (9%), the skin condition was stabilized even though he continued working. In only 2 employees (18%) did the skin condition worsen. These preliminary results showed that most of the OSD were due to lack of or unsuitable skin care and protection. The program will be extended to cover a larger number of food industry employees with OSD.