Occupational allergic contact dermatitis, partly airborne, due to isocyanates and epoxy resin

Nickel dust-induced occupational contact dermatitis by welding and grinding work in shipyard workers: a report of nine cases

Background

Occupational skin diseases are skin conditions that occur or worsen in relation to work and known to be the second most common type of occupational disease affecting individuals in the United States. In Korea, epidemiological reports related to occupational skin diseases are rare. But, no cases of occupational contact dermatitis caused by welding and grinding work have been reported previously.

Case presentation

Nine male workers working in the production department for liquefied natural gas (LNG) ships in Ulsan complained of erythematous papules/patches and itching in various areas of the body after welding and grinding work. The work environment monitoring report revealed that the amount of nickel dust exceeded the time weighted average (TWA) and poor local ventilation status. Based on the symptoms and the overall results of surveys, several tests, and work environment monitoring report, the 2 workers who had positive patch-test reactions to nickel were diagnosed with nickel dust-induced allergic contact dermatitis. The other 7 workers were diagnosed that there was a high probability that they had nickel dust-induced irritant contact dermatitis. The 2 workers who had nickel dust-induced allergic contact dermatitis were recommended to switch their jobs.

Conclusions

Nickel is one of the most common cause of allergic contact dermatitis. In this case, the dust was assumed to be created by welding work with a high nickel content new welding rod and subsequent grinding work, and the concentration of this dust exceeded the time weighted average. Thus, it is thought that the nickel dust may have caused contact dermatitis through continuous contact with the workers' exposed skin in a poorly ventilated space. Currently, several domestic shipbuilding companies are manufacturing LNG tankers using a new construction method. Consequently, it is highly likely that similar cases will occur in the future, which makes this case report meaningful.

Is the analysis of histamine and/or interleukin-4 release after isocyanate challenge useful in the identification of patients with IgE-mediated isocyanate asthma?

Isocyanates are a well-known and frequent cause of occupational asthma. The implementation of specific inhalation challenges (SICs) is the gold standard in asthma diagnosis supporting occupational case history, lung function testing, specific skin prick tests and the detection of specific IgE. However, the diagnosis is not always definitive. An interesting new approach, analyses of individual genetic susceptibilities, requires discrimination between a positive SIC reaction arising from IgE-mediated immune responses and one from other pathophysiological mechanisms. Hence, additional refinement tools would be helpful in defining sub-classes of occupational asthma and diagnosis. We used total IgE levels, specific IgE and SIC results for sub-classification of 27 symptomatic isocyanate workers studied. Some mutations in glutathione S-transferases (GSTs) are suspected either to enhance or to decrease the individual risk in the development of isocyanate asthma. Our patient groups were assessed for the point mutations GSTP1*I105V and GSTP1*A114V as well as deletions (null mutations) of GSTM1 and GSTT1. There seems to be a higher risk in developing IgE-mediated reactions when GSTM1 is deleted, while GSTT1 deletions were found more frequently in the SIC positive group. Blood samples taken before SIC, 30-60 min and 24h after SIC, were analyzed for histamine and IL-4, classical markers for the IgE-mediated antigen-specific activation of basophils or mast cells. We suggest that the utility of histamine measurements might provide an additional useful marker reflecting isocyanate-induced cellular reactions (although the sampling times require optimization). The promising measurement of IL-4 is not feasible at present due to the lack of a reliable, validated assay.

Contact allergy induced by bisphenol A diglycidyl ether leachables from aluminium tubes for pharmaceutical use

BACKGROUND

Aluminium tubes for pharmaceutical use are internally lacquered with epoxy resins (ER) based on bisphenol A diglycidyl ether (BADGE). Recently, it was shown that remnants of ER polymerization like BADGE are extractable from epoxy-based coatings of commercially available tubes and may leach into semi-solid drug preparations. We aimed to evaluate the safety of BADGE-contaminated macrogol ointments in individuals sensitized to ER based on BADGE by use tests.

METHODS

Repeated open application testing (ROAT) in 11 patients sensitized to ER based on BADGE with BADGE in macrogol ointments (3 mg/kg; 30 mg/kg, equivalent to BADGE concentration determined in macrogol ointment after storage in a commercially available tube; 300 mg/kg).

RESULTS

The 30 mg/kg BADGE ointment elicited reactions in three patients, and another three patients reacted to 300 mg/kg BADGE ointment. No reactions to the vehicle control and 3 mg/kg BADGE were observed.

CONCLUSIONS

Elevated BADGE concentrations in ER-coated aluminium tubes pose a risk of developing contact dermatitis to patients sensitized to ER based on BADGE. Quality standards are deemed necessary for the production of ER-coated aluminium tubes intended for pharmaceutical use and should consider the results of the present ROAT study.

Airborne-contact dermatitis of non-plant origin: an overview

Airborne-contact dermatitis (ABCD) represents a unique type of contact dermatitis originating from dust, sprays, pollens or volatile chemicals by airborne fumes or particles without directly touching the allergen. ABCD in Indian patients has been attributed exclusively by pollens of the plants like Parthenium hysterophorus, etc., but in recent years the above scenario has been changing rapidly in urban and semiurban perspective especially in developing countries. ABCD has been reported worldwide due to various type of nonplant allergens and their clinical feature are sometimes distinctive. Preventive aspect has been attempted by introduction of different chemicals of less allergic potential.

Contact sensitization to 4,4'-diaminodiphenylmethane and to isocyanates among general dermatology patients

BACKGROUND

Diisocyanates and 4,4'-diaminodiphenylmethane (MDA) are industrial sensitizers. Occupational asthma is a risk among workers exposed to diisocyanates. Exposure may also lead to contact sensitization and allergic contact dermatitis.

OBJECTIVE

The aim of this study was to determine the occurrence of contact sensitization to MDA and to diisocyanates among general dermatology patients.

PATIENTS AND METHODS

Patch testing with MDA was carried out in 1595 patients. Diphenylmethane-4,4'-diisocyanate (MDI) and toluene-2,4-diisocyanate (TDI) were tested in 1023 patients and isophorone diisocyanate (IPDI) and 1,6-hexamethylene diisocyanate (HDI) in 433 patients. The clinical data and sources of exposure are analysed.

RESULTS

MDA reactions were seen in 17 (1.1%) patients and MDI reactions in 4 patients. Six MDA-positive patients reacted to p-phenylenediamine and two to epoxy chemicals. 5/10 of the TDI reactions were seen concurrently with reactions to MDI, MDA, HDI, or to IPDI. IPDI reactions were seen in eight patients and HDI reactions in two patients. Possible sources of exposure were traced in most patients, although the association with the current dermatitis was not apparent in all cases.

CONCLUSION

(Di)isocyanates may induce contact sensitization with or without allergic contact dermatitis.

An attempt to improve diagnostics of contact allergy due to epoxy resin systems. First results of the multicentre study EPOX 2002

Epoxy resin systems (ERSs) are a frequent cause of occupational allergic contact dermatitis. Sensitization occurs not only to the resins, but also to hardeners and reactive diluents. However, only a fraction of the ERS components currently in use are available for patch testing. With the multicentre study EPOX 2002, we attempted to improve diagnostics in this field by patch testing with components currently used in ERSs. During the first study period (October 2002 to July 2003), in addition to commercially available ERS patch test substances, 16 study substances (1 resin, 9 hardeners and 6 reactive diluents) were patch tested in 70 patients with suspected contact allergy due to ERSs and 22 patients with a prior positive patch test reaction to epoxy resin (ER) in the standard series. Most frequently, allergic reactions to ER based on diglycidyl ether of bisphenol A and F were observed (55.2% and 43.7%, respectively). Agreement between positive reactions to both resins, which can be explained by immunological cross-sensitization and/or coexposure, was substantial [Cohen's kappa 0.65 (95% CI: 0.49-0.80)]. Among the reactive diluents, 1,6-hexanediol diglycidyl ether (1,6-HDDGE) and 1,4-butanediol diglycidyl ether (1,4-BDDGE) were the most frequent allergens, with 19.5% and 18.4% positive reactions, respectively. Although agreement between positive reactions to 1,6-HDDGE and 1,4-BDDGE was even better than with the 2 resins, the sample size is considered too small to decide reliably whether 1,6-HDDGE alone could serve as a marker allergen for both. Allergic reactions to p-tert-butylphenyl glycidyl ether and to phenyl glycidyl ether (PGE) occurred in 11.5% of the patients tested, with only moderate agreement. All patients positive to cresyl glycidyl ether (6.8%) also reacted to PGE. Of the hardeners tested, m-xylylene diamine was the most frequent allergen (13.8%), followed by isophorone diamine (5.7%). No reactions were observed to several substances, the test concentration of which may have been too low and will be increased in the future.

Gastric outflow obstruction after ingestion of wood glue in a dog

A 2-year-old, male, mixed-breed dog presented with a 12-day history of vomiting, depression, and weight loss after ingestion of industrial-strength wood glue containing diphenylmethane diisocyanate as its active ingredient. A diagnosis of gastric foreign body was made from survey abdominal radiographs. A large aggregate of solidified wood glue was surgically removed, and the dog recovered uneventfully. Fourteen other cases have been reported to the Animal Poison Control Center at the American Society for the Prevention of Cruelty to Animals (ASPCA). Eight of those 14 cases required surgical intervention. All cases recovered completely.

Evaluation of self-reported skin problems among workers exposed to toluene diisocyanate (TDI) at a foam manufacturing facility

Toluene diisocyanate, or TDI (CAS 584-84-9) is a well-known asthmagen and respiratory irritant. TDI is also known for its ability to irritate the skin and mucous membranes. To further investigate the dermal effects of TDI, NIOSH investigators conducted a cross-sectional study at a flexible foam manufacturing plant. A total of 114 workers participated in the study. Participants completed a medical questionnaire, provided blood for antibody testing to TDI and other allergens, and a subset of participants reporting skin symptoms underwent skin patch testing to a standard diisocyanate panel. Production line workers were more than twice as likely to report skin problems as those working in nonproduction areas (PRR = 2.66; 95% CI = 1.14-16.32; P = 0.02). Age, gender and duration of employment at the plant were comparable among participants working in production and nonproduction areas. Of the 100 participants who provided blood samples for antibody testing, specific IgG antibody to TDI was detected in two individuals, and none of the samples demonstrated specific IgE antibody to TDI. Of the 26 workers who underwent skin patch testing, none developed reactions to the diisocyanate allergens. These results suggest that the skin symptoms among study participants represent an irritant rather than an immunologic reaction to TDI, or to an unidentified allergen present in the foam.

Occupational allergic contact dermatitis caused by isocyanates

Between 1978 and 2001, 22 patients were diagnosed with occupation-related allergic contact dermatitis from isocyanates and/or polyurethanes in our clinic. 13 had a positive reaction to the isocyanates, of whom 10 also reacted to diaminodiphenylmethane (MDA), which is used in the production or processing of isocyanates and polyurethanes; 9 reacted only to MDA. The object of the present study was to identify the trades and industries responsible for the development of contact allergy to these resins. Such patients must be patch tested with the isocyanates contacted at work, and account must be taken of positive reactions to MDA as a marker for isocyanate sensitivity.

An update on airborne contact dermatitis

This review is an update of 2 previously published articles on airborne contact dermatoses. Because reports in the literature often omit the term 'airborne', 18 volumes of Contact Dermatitis (April 1991-June 2000), 8 volumes of the American Journal of Contact Dermatitis (1992 1999) and 4 volumes of La Lettre du Gerda (1996-1999) were screened, and the cases cited were classified as to history, lesion locations, sensitization sources, and other factors. Reports on airborne dermatitis are increasingly being published, sometimes in relation to specific occupational areas.