- Email: [email protected]
Occupational allergic contact dermatitis to nitromethane
CASE REPORT
Occupational Allergic Contact Dermatitis to Nitromethane Kelli G. Webb and Joseph F. Fowler Jr Nitromethane has wide industrial and commercial application as a polar solvent for adhesives and acrylics as well as explosive fuel. Allergic contact dermatitis to this chemical has not been described previously. The authors documented allergic contact hand dermatitis in 4 coworkers who similarly handled an adhesive solvent containing nitromethane. All 4 cases were confirmed by patch testing and resolved after allergen avoidance. Copyright 2002, Elsevier Science (USA). All rights reserved.
T
HE CHEMICAL NITROMETHANE, CH3NO2, is used as a solvent for adhesives and acrylics, as well as in fuels. To date, allergic contact dermatitis (ACD) to this compound has not been described. We report 4 cases of allergic contact hand dermatitis in female coworkers at an automobile parts manufacturer who similarly handled an adhesive solvent containing nitromethane while performing their factory line duties.
Cases Case 1
A 24-year-old woman had hand dermatitis shortly after being placed on a line assembling car doors. She presented with erythema, blistering, and significant pruritus of the right index finger and palmar surface for 1 to 2 months. Patch testing showed a reaction to nitromethane, as well as nickel sulfate (Table 1). With total avoidance of the nitromethane-containing compound, the patient’s symptoms cleared completely and have remained clear at 5 month follow-up. Case 2
A 31-year-old woman had hand dermatitis since working on a line assembling car doors for over a year. Previously, she had used topical steroids with some benefit and improved markedly after a 2-week vacation. She presented with moderate bilateral, dorsal, and palmar hand dermatitis that was very pruritic. Patch testing showed a reaction to nitromethane as well as to gold, although the gold allergy was not felt to be relevant to the presenting complaint (Table 1). At 5 months follow-up, this patient continues to experience mild to moderate hand dermatitis. Unfortunately, she has had difficulty avoiding the nitromethaneFrom the Division of Dermatology, University of Louisville, Louisville, KY. Address reprint requests to Joseph F. Fowler, Jr, MD, Division of Dermatology, University of Louisville, 444 S, First St, Louisville, KY 40202. Copyright 2002, Elsevier Science (USA). All rights reserved. 1046-199X/02/1304-0009$35.00/0 doi:10.1053/ajcd.2002.36640
containing adhesive because the night shift continues to use this product in her work space. Case 3
A 30-year-old woman presented with reports of significant pruritus and cracking of the skin of the bilateral first through third fingers for 6 to 8 weeks. The patient’s hand dermatitis improved somewhat after a week vacation, and patch testing showed a reaction to nitromethane (Table 1). The patient was moved off of the line assembly with no contact to the nitromethane-containing adhesive, and her dermatitis has resolved completely. Case 4
A 47-year-old woman who works in quality control overseeing the assembly and repair of car doors presented with bilateral hand dermatitis. This patient described problems with her hands for approximately 4 months and noticed considerable improvement after a 2-week vacation. Her symptoms flared after returning to work and, on evaluation, dermatitis involved the left first and second fingers. Patch testing showed a reaction to nitromethane (Table 1). At 2-month follow-up, the patient’s condition had flared significantly because of the frictional irritation that occurs as she runs her hands over finished products, and she required a prednisone taper and fluticasone proprionate cream. At 5-month follow-up, however, after vigilant avoidance, her hand dermatitis has resolved completely.
Discussion We could find no reported ACD associated with the use of nitromethane. This solvent is used widely in industry primarily as a stabilizer of hydrocarbons to form stable noncorrosive mixtures for degreasing, dry cleaning, and for cleaning semiconductors and lenses.1 It also is used as a polar solvent for adhesives and acrylic coatings as well as a fuel by professional drag racers and in explosives.1,3 Resins with wide commercial application including, vinyl, epoxy, and polyamide and acrylic polymers are soluble in nitroparaffins, such as nitromethane.2 Importantly, nitrometh-
American Journal of Contact Dermatitis, Vol 13, No 4 (December), 2002: pp 201-202
201
Webb and Fowler
202
Table 1. Nitromethane Patch Testing Results
Patient 1 Patient 2 Patient 3 Patient 4 Controls (6)
48 Hours
96 Hours
2⫹ 2⫹ 3⫹ 3⫹ Negative
2⫹ 2⫹ 3⫹ 3⫹ Negative
ane is a major component of the degreasing solvent to which our 4 patients were exposed cutaneously during factory line work. The toxicology of nitromethane has been studied extensively in animal models. It is considered toxic when ingested but less so when inhaled or absorbed via the skin. The most common route of occupational exposure to nitromethane is via inhalation of vapors, and health effects described in the literature include narcosis, liver and thyroid toxicity, blood dyscrasias, and peripheral neuropathy.3,4 False elevation of serum creatinine on determination with the Jaffe reaction after cutaneous absorption of nitromethane has been described, as well as a symmetric demyelinating disorder after occupational exposure.2,5 Our 4 patients, however, experienced hand dermatitis determined to be a true allergic contact dermatitis based on
patch testing (Table 1). Further conclusive evidence was clearing on allergen avoidance and the absence of any patch test reactivity in the 6 control subjects. Given the myriad potential applications of this chemical and widespread industrial use among over 134,000 workers in the United States alone,3 we believe it important to recognize the potential for allergic contact dermatitis. Industrial employees who are exposed to nitromethane should be encouraged to wear protective clothing, including gloves, and be removed from contact with nitromethane if allergy occurs.
References 1. Nitromethane. IARC Monogr Eval Carcinog Risks Hum. 77:487-501, 2000 2. Gabrielli A, Hammett-Stabler C: False elevation of serum creatinine following skin absorption nitromethane complicates the clinical diagnosis of rhabdomyolysis. Chest 113:1419-1422, 1998 3. Page E, Pajeau A, Arnold T, et al: Peripheral neuropathy in workers exposed to nitromethane. Am J Ind Med 40:107-113, 2001 4. American Conference of Governmental Industrial Hygienists (ACGIH): Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH, American Conference of Governmental Industrial Hygienists, 2000 5. Sclar G: Encephalomyeloradiculoneuropathy following exposure to an industrial solvent. Clin Neurol Neurosurg 101:199-202, 1999
Occupational Allergic Contact Dermatitis to Nitromethane Kelli G. Webb and Joseph F. Fowler Jr Nitromethane has wide industrial and commercial application as a polar solvent for adhesives and acrylics as well as explosive fuel. Allergic contact dermatitis to this chemical has not been described previously. The authors documented allergic contact hand dermatitis in 4 coworkers who similarly handled an adhesive solvent containing nitromethane. All 4 cases were confirmed by patch testing and resolved after allergen avoidance. Copyright 2002, Elsevier Science (USA). All rights reserved.
T
HE CHEMICAL NITROMETHANE, CH3NO2, is used as a solvent for adhesives and acrylics, as well as in fuels. To date, allergic contact dermatitis (ACD) to this compound has not been described. We report 4 cases of allergic contact hand dermatitis in female coworkers at an automobile parts manufacturer who similarly handled an adhesive solvent containing nitromethane while performing their factory line duties.
Cases Case 1
A 24-year-old woman had hand dermatitis shortly after being placed on a line assembling car doors. She presented with erythema, blistering, and significant pruritus of the right index finger and palmar surface for 1 to 2 months. Patch testing showed a reaction to nitromethane, as well as nickel sulfate (Table 1). With total avoidance of the nitromethane-containing compound, the patient’s symptoms cleared completely and have remained clear at 5 month follow-up. Case 2
A 31-year-old woman had hand dermatitis since working on a line assembling car doors for over a year. Previously, she had used topical steroids with some benefit and improved markedly after a 2-week vacation. She presented with moderate bilateral, dorsal, and palmar hand dermatitis that was very pruritic. Patch testing showed a reaction to nitromethane as well as to gold, although the gold allergy was not felt to be relevant to the presenting complaint (Table 1). At 5 months follow-up, this patient continues to experience mild to moderate hand dermatitis. Unfortunately, she has had difficulty avoiding the nitromethaneFrom the Division of Dermatology, University of Louisville, Louisville, KY. Address reprint requests to Joseph F. Fowler, Jr, MD, Division of Dermatology, University of Louisville, 444 S, First St, Louisville, KY 40202. Copyright 2002, Elsevier Science (USA). All rights reserved. 1046-199X/02/1304-0009$35.00/0 doi:10.1053/ajcd.2002.36640
containing adhesive because the night shift continues to use this product in her work space. Case 3
A 30-year-old woman presented with reports of significant pruritus and cracking of the skin of the bilateral first through third fingers for 6 to 8 weeks. The patient’s hand dermatitis improved somewhat after a week vacation, and patch testing showed a reaction to nitromethane (Table 1). The patient was moved off of the line assembly with no contact to the nitromethane-containing adhesive, and her dermatitis has resolved completely. Case 4
A 47-year-old woman who works in quality control overseeing the assembly and repair of car doors presented with bilateral hand dermatitis. This patient described problems with her hands for approximately 4 months and noticed considerable improvement after a 2-week vacation. Her symptoms flared after returning to work and, on evaluation, dermatitis involved the left first and second fingers. Patch testing showed a reaction to nitromethane (Table 1). At 2-month follow-up, the patient’s condition had flared significantly because of the frictional irritation that occurs as she runs her hands over finished products, and she required a prednisone taper and fluticasone proprionate cream. At 5-month follow-up, however, after vigilant avoidance, her hand dermatitis has resolved completely.
Discussion We could find no reported ACD associated with the use of nitromethane. This solvent is used widely in industry primarily as a stabilizer of hydrocarbons to form stable noncorrosive mixtures for degreasing, dry cleaning, and for cleaning semiconductors and lenses.1 It also is used as a polar solvent for adhesives and acrylic coatings as well as a fuel by professional drag racers and in explosives.1,3 Resins with wide commercial application including, vinyl, epoxy, and polyamide and acrylic polymers are soluble in nitroparaffins, such as nitromethane.2 Importantly, nitrometh-
American Journal of Contact Dermatitis, Vol 13, No 4 (December), 2002: pp 201-202
201
Webb and Fowler
202
Table 1. Nitromethane Patch Testing Results
Patient 1 Patient 2 Patient 3 Patient 4 Controls (6)
48 Hours
96 Hours
2⫹ 2⫹ 3⫹ 3⫹ Negative
2⫹ 2⫹ 3⫹ 3⫹ Negative
ane is a major component of the degreasing solvent to which our 4 patients were exposed cutaneously during factory line work. The toxicology of nitromethane has been studied extensively in animal models. It is considered toxic when ingested but less so when inhaled or absorbed via the skin. The most common route of occupational exposure to nitromethane is via inhalation of vapors, and health effects described in the literature include narcosis, liver and thyroid toxicity, blood dyscrasias, and peripheral neuropathy.3,4 False elevation of serum creatinine on determination with the Jaffe reaction after cutaneous absorption of nitromethane has been described, as well as a symmetric demyelinating disorder after occupational exposure.2,5 Our 4 patients, however, experienced hand dermatitis determined to be a true allergic contact dermatitis based on
patch testing (Table 1). Further conclusive evidence was clearing on allergen avoidance and the absence of any patch test reactivity in the 6 control subjects. Given the myriad potential applications of this chemical and widespread industrial use among over 134,000 workers in the United States alone,3 we believe it important to recognize the potential for allergic contact dermatitis. Industrial employees who are exposed to nitromethane should be encouraged to wear protective clothing, including gloves, and be removed from contact with nitromethane if allergy occurs.
References 1. Nitromethane. IARC Monogr Eval Carcinog Risks Hum. 77:487-501, 2000 2. Gabrielli A, Hammett-Stabler C: False elevation of serum creatinine following skin absorption nitromethane complicates the clinical diagnosis of rhabdomyolysis. Chest 113:1419-1422, 1998 3. Page E, Pajeau A, Arnold T, et al: Peripheral neuropathy in workers exposed to nitromethane. Am J Ind Med 40:107-113, 2001 4. American Conference of Governmental Industrial Hygienists (ACGIH): Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH, American Conference of Governmental Industrial Hygienists, 2000 5. Sclar G: Encephalomyeloradiculoneuropathy following exposure to an industrial solvent. Clin Neurol Neurosurg 101:199-202, 1999