4,4'-methylenedicyclohexyl diisocyanate

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Allergic contact dermatitis caused byisocyanates in resin jewellery

Author:

Nguyen R & Lee A

Year:

2012

Bibliographic source:

Contact Dermatitis 67, 56-57

Reference 2

Reference Type:

other: conference abstract

Title:

Allergic contact dermatitis from isocyanates in resin jewellery

Author:

Lee

Year:

2010

Bibliographic source:

Contact Dermatitis 63 (Suppl. 1), 58–107

Materials and methods

Type of sensitisation studied:

skin

Study type:

case report

Principles of method if other than guideline:

After a case of allergic contact dermatitis patch testing was performed with the Chemotechnique European baseline series and with the patient’s own materials. Patch tests were read on D3 and D6 according to the International Contact Dermatitis Research Group criteria.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-methylenedicyclohexyl diisocyanate

EC Number:

225-863-2

EC Name:

4,4'-methylenedicyclohexyl diisocyanate

Cas Number:

5124-30-1

Molecular formula:

C15H22N2O2

IUPAC Name:

1,1'-methylenebis(4-isocyanatocyclohexane)

Details on test material:

- Name of test material (as cited in case report): two-part polyurethane resin system that, according to the Material Safety Data Sheet (MSDS), contained 70–90% 4,4-dicyclohexylmethane-diisocyanate (DMDI; CAS 5124-30-1).

Method

Type of population:

general

Subjects:

- Number of subjects exposed: 1
- Sex: female
- Age: 35 years
- Other: A 35-year-old female office worker attended a popular weekend course to develop her interest in making resin jewellery. This involved using a two-part polyurethane resin system.

Clinical history:

- History of allergy or casuistics for study subject or populations: no data
- Aggravating factors both in home and workplace: no data
- Family history: no data
- Medical history (for respiratory hypersensitivity): no data
- Any other allergic or airway disorders: no data
- Smoking history: no data
- Exposure history: With respect to DMDI not explicitly mentioned.
- Symptoms, onset and progress of the disease: On one occasion when the patient did not use gloves, her skin came into direct contact with the polyurethane mixture. The next day, she developed an acute pruritic eruption on her right index finger. Two weeks later, after further resin jewellery making, she developed a pruritic eczematous eruption on her face, neck, and hands. This resolved with topical and oral corticosteroids and avoidance of further jewellery making. There were no associated respiratory symptoms. She no longer undertakes any jewellery making, and has had no recurrences.

Route of administration:

dermal

Details on study design:

TYPE OF TEST(S) USED: patch test (epicutaneous test)

ADMINISTRATION
Patch testing was performed with the Chemotechnique European baseline series including diaminodiphenylmethane (MDA) (0.5% pet.), toluene diisocyanate (TDI, 2% pet.), 4,4-diphenylmethane diisocyanate (MDI, 2% pet), 1,6-hexamethylene diisocyanate (HDI) (0.1% pet.), and the patient’s own polyurethane resin system (2% pet.). The main component of the patient’s own product, DMDI, was not available for testing.

EXAMINATIONS
Patch tests were read on D3 and D6 according to the International Contact Dermatitis Research Group criteria.

Results and discussion

Results of examinations:

RESULT OF CASE REPORT
Positive reactions were observed to the patient’s own system (D3 ++, D6 ++), HDI (D6 +) and MDA (D6 +), negative reactions were observed to TDI and MDI. In this case, the patient reacted to HDI, which was not found in the polyurethane resin system she used, and which it was anticipated she had no prior exposure to. To explain this, the authors indicate that cross-reactivity to HDI might be the reason. The patient also reacted to MDA without any prior exposure.