Allergic biocides

Skin contact with metalworking fluids may cause skin irritation or a contact irritant dermatitis. Contact with neat oils may cause folliculitis (oil acne). Contact with some aqueous-mix fluids may, depending upon the additives, e.g. biocides, cause an allergic contact dermatitis. Formerly the use of unrefined mineral oils posed a risk of skin cancer. 

Parabens (including methyl-, ethyl-, propyl-, and butylparaben) are used widely in pharmaceutical products as a biocidal agent. The majority of allergic reactions to parabens are observed after topical exposure. Delayed hypersensitivity contact dermatitis occurs more often in individuals with preexisting dermatitis. Immediate hypersensitivity after parenteral administration is rare. Although these... 

NRL is an irritant because of the protein allergens and can cause allergic skin reactions associated with type I (immediate effect) hypersensitivities of hand dermotoses and immunologic contact urticaria . It is also possible to have type IV (delayed effect) hypersensitivities of NRL, due to the chemicals added during its processing (such as accelerators of the thiuram/carbamate/mercaptobenzothiazole types needed for vulcanisation, a number of different antioxidants/antiozonants, emulsifiers, extenders, colorants, retarders, stiffeners, biocides). Either of these types can be serious and even life threatening in some cases [75]. 

Biocides are additives that impart protection against mold, mildew, fimgi, and bacterial growth to materials. Without biocides, polymeric materials in the proper conditions can experience surface growth, development of spores causing allergic reactions, unpleasant odors, staining, embrittlement, and premature product failure. It is important to note that the biocide protects the material, not the user of the final product. 

Table 7. Allergic reactions to different biocides in unequivocal (++/+++) formaldehyde allergic patients (from Schnuch and Geier ...

Chloroacetamide (CAS no. 79-07-2). This is a well-known cosmetic biocide, but sensitization is less common than with parabens. An allergic reaction was reported to deodorant (Taran and Delaney 1997) The patch-test concentration is 0.2% pet. Allergic reactions do occur. 

Dichlorophene (Anthiphen, Dicestal, Didroxane, Di-phenthane-70, G-4, Hyosan, Parabis, Plath-lyse, Preventol G-D, Teniathane, Teniatol, Wespuril, CAS no. 97-23-4). This is a biocide in many soaps, shampoos, hair tonics, liquid make-up products, etc. As a preservative in many dentifrices, it has caused dermatitis of the mouth, mostly allergic, with cheilitis and stomatitis (Andersen and Ham-ann 1984). The patch-test concentration is 1% pet. Irritant patch tests are common. Photoallergic reactions are reported (Menz et al. 1982). Crossreactions with bithionol, hexachlorophene and halogenated salicylanilides are possible. 

Allergic contact dermatitis is the most important occupational skin disease among painters. The consequences can be serious the sensitized workers may, for instance, have been obliged to change their occupation (Mathias 1984 Holmes 1993). Since the 1970s, synthetic resins have replaced turpentine as the most important causes of sensitization caused by paints (Mathias 1984 Jolanki 1991 Holmes et al. 1993 Kanerva 1995). Other causes include biocides necessary in water-based paints, and other additives such as hardeners or accelerators and inhibitors of polymerization (Mathias 1984 Fischer 1990, 1995). There are also several other potential causes, including plasticizers, dryers and chromates (Mathias 1984 Fischer et al. 1990). Formaldehyde and rubber chemicals, as well as turpentine and other natural products, can also be included in the list of potential allergens. 

Biocides are the second most common cause of allergic contact dermatitis after synthetic resins. The problem of sensitization to biocides has become more common because of the increased use of water-based latex paints. Table 5 gives a list of the biocides used in paints. Similar biocides are also used in the glues needed by wallpaper hangers. 

Clay handlers can develop irritant dermatitis from wet clay and allergic contact dermatitis from biocides added to the clay. A case of occupational cold urticaria has been reported in an operative who developed whealing after contact with cold wet clay, especially during the winter months (Fitzgerald et al. 1995). 

O Driscoll JB, Beck MH ( 88) Occupational allergic contact dermatitis from Kathon WT. Contact Dermatitis 19 63 Pilger C, Nethercott JR, Weksberg F (1986) Allergic contact dermatitis due to a biocide containing 5-chloro-2-methyl-4-isothiazolin-3-one. Contact Dermatitis 14 201-204 Piraccini BM, Peluso A, De Maria P, Tosti A (1991) Occupational contact dermatitis due to the disinfectant Tego Diocto S . Contact Dermatitis 24 228-229... 

Rycroft RJG, Neild VS (1992) Allergic contact dermatitis from MCI/MI biocide in a printer. Contact Dermatitis 26 142... 

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