Fluctuations in the prevalence of chromate allergy in Denmark and exposure to chrome-tanned leather.

BACKGROUND

A recent Danish study showed a significant increase in the prevalence of chromate contact allergy after the mid-1990s, probably as a result of exposure to leather products.

OBJECTIVES

To reproduce the results by analysing data from the period 1992-2009 at Odense University Hospital, Denmark. The temporal development in the occurrence of chromate contact allergy and assumed causative exposures were investigated.

PATIENTS, MATERIALS AND METHODS: A retrospective analysis of patch test data was performed (n = 8483), and medical charts from patients with chromate allergy (n = 231) were reviewed. Comparisons were made using the χ(2) -test. A test of the reproducibility of the TRUE Test® was also performed. Logistic regression analyses were used to test for associations.

RESULTS

No significant changes in the prevalence or exposure sources of chromate allergy during 1992-2009 were identified. Leather shoes (24.4%) were the most frequent exposure sources in chromate allergy, and were mainly registered in women, although the difference between men and women was not significant (P = 0.07). Cement and leather glove exposure occurred significantly more often in men than in women (P = 0.002). Foot dermatitis (40.3%) was the most frequent anatomical location, apart from hand eczema (60.6%). The reproducibility of the TRUE Test® was 93.3%.

CONCLUSIONS

Apart from hand eczema, the most frequent clinical picture of chromate allergy was foot dermatitis caused by leather shoe exposure. A tendency for an increasing prevalence of chromate contact allergy from 1997 was shown, but no significant change was detectable.