Diagnosis and Treatment of Dermatitis Due to Formaldehyde Resins in Clothing

Ryan M. Carlson; Mary C. Smith; Susan T. Nedorost


Dermatitis. 2004;15(4):169-175. 

In This Article


The prevalence of textile formaldehyde resin dermatitis in the United States has previously been established as 1.2 to 2.3% of an eczematous population.[5,6,11] The North American Contact Dermatitis Group (NACDG) for 1998 to 2000 tested 50 allergens on more than 5,800 patients suspected of having contact dermatitis.[12] Results from tests with formaldehyde 1% aqueous were positive in 9.2% of patients, a percentage that has remained stable since the 1994-to-1996 data were collected.[13,14] Our data show that 10% of men tested positively for formaldehyde but that only about 5% of women in our population were allergic to formaldehyde. Unfortunately, the NACDG data have no breakdown by gender, which would be interesting for comparison. The gender difference in our population may be explained by the large number of machinists in our area who are occupationally exposed to formaldehyde-releasing biocides in coolants. In the NACDG data, Fixapret AC was found to be reactive in 5% of those tested, down from 7.2% since the release of the 1996-to-1998 NACDG data.[14] Sensitization to this screening mix in our population was lower, at around 2%.

Variation between medical centers in regard to the incidence of textile dermatitis and to the results of patch tests with textile resins may result from several factors. Variation may occur owing to differences in climate as humidity and perspiration may cause more resin to leach from garments. Also, clinics vary in their timing of patch-test readings. For instance, the relatively late readings in our clinic may have enhanced the detection of very-late-reacting antigens. Additionally, this may decrease the sensitivity for antigens that react early (days 2 to 3) and are subsequently lost early. The reactivity of different formaldehyde resins may peak at different times so that results will vary depending on when one reads the results.

The above data depict a greater percentage of men than women having positive patch-test results from formaldehyde as well as from some of the textile resins. Historically, women have tended to be afflicted with textile dermatitis more often than men;[1] estimates have ranged from 3:1 to 5:1, favoring women.[15,16] It was thought that the tighter fit of women's clothing to skin when compared to men's clothing was a possible explanation.[1] Our data show that this trend may now be reversing, approximating a ratio of 1:1. In 1992, Fowler and colleagues' study group consisted of 9 women and 8 men with positive test reactions to formaldehyde resins.[6] Our data, which include a total of 852 patients, show an incidence rate of 10% in men for formaldehyde allergy alone and show that a greater percentage of men than women react to several of the formaldehyde resins. The higher incidence of formaldehyde allergy in men in our population may influence the number of men who also cross-react to formaldehyde-related textile finishes.

The automotive industry is the backbone of the regional economy for our patient population, and many retired men in this region have had occupational exposure to formaldehyde released from biocides. Thirty-eight of the 198 patients for whom we listed occupational data in our database were retired. More retired men than women had positive reactions to the formaldehyde textile resins. This included 3 of the 18 retired men who reacted positively to formaldehyde, and all three of these men were sensitive to at least one formaldehyde resin. Of the 20 retired women, none were found to have positive reactions to formaldehyde or formaldehyde resin on patch testing. However, 2 of the 3 textile-allergic women--one a dialysis technician, the other a machinist--for whom we have occupational data also had opportunities for occupational sensitization to formaldehyde in the forms of disinfectant for dialysis tubing and biocide, respectively. The dialysis technician was exposed and sensitized while working and then reacted positively to formaldehyde resins in her laboratory coat. The machinist who tested positive was one of only six female machinists in our database. We speculate that many patients who are allergic to textile resins are originally sensitized to formaldehyde and then cross-react with the textile resin finishes later in life.

Success in the treatment of ACD lies in identifying its cause correctly and educating the patient about avoidance of the allergen. Patients who are allergic to formaldehyde may also cross-react with formaldehyde-releasing preservatives such as quaternium-15. With certain allergens (eg, vehicles and preservatives) found in topical preparations, it is important to impress upon patients the need to read labels. The Contact Allergen Replacement Database (CARD) may be helpful in finding products that are free of these formaldehyde-releasing preservatives.[17]

Formaldehyde can also be released from the formaldehyde-releasing resins used to make stain- and wrinkle-resistant clothing. Table 4 lists manufacturers we located who claim to use low-formaldehyde-releasing resins or no such resins, as well as manufacturers who market in Japan. A low-formaldehyde-releasing resin is one that releases 75 ppm. (This is also the Japanese standard for textile finishes, as opposed to 300 ppm in the United States).[1] This information was collected by contacting industries and inquiring about the use of formaldehyde resins in their textiles. Only manufacturers who replied and wished to be included in this study are listed. These newer resin-yielding fabrics that claim to contain fewer than 75 ppm free formaldehyde may cause occasional reactions but are more likely to be tolerated by patients with textile dermatitis.[9]

Although some US manufacturers are using newer low-formaldehyde or "no formaldehyde" finishes, the amount of clothing being imported is increasing, and we are unaware of the details of these overseas manufacturers' finishing techniques (ie, the amount of formaldehyde used).[5] In 2001, a comprehensive database containing information about Japanese textiles and their manufacturers was opened to individuals seeking Japanese clothing. This company (Coromo, Inc., Tokyo, Japan) provides an international gateway to Japan's fashion world and may be helpful to physicians in periodically updating information about companies that market in Japan.[18] Japan enforces the strictest standards for formaldehyde release from textile finishes. Also, the companies that market in or out of Japan meet acceptable standards, and their products are generally safe (AJ Scheman, personal communication, February 2004) (see Table 4 ).[19]

There are also those 30% of patients who have negative patch-test results for formaldehyde but positive results for the formaldehyde resins. It is believed that these patients are not reacting to the formaldehyde released by the resins but rather are reacting to the resins themselves. Thus, we recommend testing persons suspected of textile allergy with the formaldehyde resins Fixapret AC and Fixapret CPN.

The lack of clear labeling on clothing contributes to the difficulty in avoiding formaldehyde resins. The care symbols, conceived by the American Society for Testing and Materials, were instituted to make laundry care easier. Interestingly, a permanent-press symbol in the shape of a bucket with one line underneath exists; however, there is no standardization for its usage (J. Pullen, E-mail communication, February 12, 2004). In other words, manufacturers may recommend this wash cycle for apparel that does not have a "permanent-press" finish because it will reduce the formation of wrinkles. Thus, patients with formaldehyde-related textile dermatitis are unable to make use of these laundry care symbols with certainty when selecting which clothing to purchase.

Unfortunately for patients and physicians, the allergenic component of many materials are rarely labeled. The lack of labeling on textile fabrics is a major contributor to the difficulty of avoiding allergens. CARD is not helpful in regard to clothing. Recommendations regarding the avoidance of specific textiles and textile resins were spelled out in the patient handout (see Table 5 ). Counseling and encouragement are especially helpful at this stage.