Sensitivity to m-phenlenediamine.

Area of Science:

• Occupational Dermatology
• Chemical Sensitization
• Allergy and Immunology

Background:

• Occupational exposure to m-phenylenediamine (MPD) can cause contact dermatitis in workers.
• MPD is used as a hardener in various industrial applications.
• Understanding sensitization patterns is crucial for preventing occupational skin diseases.

Purpose of the Study:

• To investigate the incidence of primary contact sensitivity to m-phenylenediamine in exposed workers.
• To explore the relationship between MPD sensitivity and co-sensitization to other chemicals like epoxy resin and triethylenetetramine.
• To analyze cross-reactivity patterns between different phenylenediamine isomers and related aromatic amines.

Main Methods:

• Patch testing was performed on workers handling m-phenylenediamine.
• Data collected on the onset of dermatitis in relation to exposure duration and co-exposure.
• Analysis of positive patch test results for m-phenylenediamine, p-phenylenediamine, o-phenylenediamine, and meta isomers of other aromatic amines.

Main Results:

• Primary contact sensitivity to m-phenylenediamine was observed in 8 out of 182 workers.
• Shorter dermatitis onset occurred in workers with simultaneous sensitivity to epoxy resin and/or triethylenetetramine.
• Significant cross-reactivity was noted: over 40% of p-phenylenediamine-sensitive patients were also sensitive to m-phenylenediamine, and many of these also reacted to o-phenylenediamine.

Conclusions:

• M-phenylenediamine is a significant occupational sensitizer, causing contact dermatitis in a notable proportion of exposed workers.
• Co-sensitization with epoxy resin and triethylenetetramine accelerates dermatitis development.
• Cross-reactivity among phenylenediamine isomers and related aromatic amines is common, necessitating comprehensive diagnostic approaches.