Formaldehyde-releasers: relationship to formaldehyde contact allergy. Part 2: Metalworking fluids and remainder

We have reviewed formaldehyde-releasers used in metalworking fluids (MWFs) in this and a previous part of a two-part article. These biocides do not appear to be frequent or important sensitizers. Even in highly selected patient groups of metalworkers, mean prevalence rates of sensitivity are low: 0.2% for Tris(hydroxymethyl)nitromethane, 1.6% for tris(N-hydroxyethyl)hexahydrotriazine, 1.9% for Bioban P-1487 and Bioban CS-1246, and 2.8% for Bioban CS-1135. In the case of the Biobans, many reactions may have been irritant. Only N,N'-methylenebis(5-methyloxazolidine) has a fairly high mean score of 4.0% in metalworkers. With the exception of Bioban P-1487, there is a clear relationship between positive patch test reactions to the releasers and formaldehyde sensitivity: 40-70% of reactions to releasers occur in patients sensitive to formaldehyde and may therefore be caused by formaldehyde allergy. There is a lack of reliable data on the clinical relevance of contact allergy to the formaldehyde releasers in MWF. In most studies, no data on relevance were provided and in those that did, relevance was often found for a (very small) minority of the reactions only. Also discussed here are the formaldehyde-releasers MDM hydantoin, methenamine, N-methylolchloracetamide, paraformaldehyde, and Preventol D2.

Formaldehyde-releasers: relationship to formaldehyde contact allergy. Metalworking fluids and remainder. Part 1

This is part of a series of review articles on formaldehyde-releasers and their relationship to formaldehyde contact allergy. Formaldehyde-releasers used in metalworking fluids (MWF) and a group of releasers not presented in previous articles are discussed. Here, in Part 1 of the article, there is a short overview of the composition and functions of MWF, the function of biocides in them, and adverse reactions to MWF. In addition, the releasers in MWF that have caused contact allergy are presented with CAS, synonyms, molecular formula, chemical structure, applications, patch test studies, and amount of formaldehyde released by them. In Part 2 of the article, the relationship between formaldehyde-releasers used in MWF and formaldehyde contact allergy is discussed as are data on miscellaneous releasers not previously presented, followed by a discussion of Parts 1 and 2 of the article.