Quantitative aspects of nickel dermatitis. Sensitization and eliciting threshold concentrations

Area of Science:

• Dermatology
• Toxicology
• Environmental Health

Background:

• Nickel allergy is a prevalent contact allergy, particularly affecting females, with significant population prevalence.
• Primary nickel sensitization stems from specific nickel exposures, not trace environmental amounts.
• Established thresholds for non-sensitizing nickel concentrations exist for consumer products.

Purpose of the Study:

• To review and synthesize current knowledge on nickel sensitization and dermatitis.
• To evaluate the relationship between nickel exposure levels and allergic reactions.
• To determine the preventability of nickel allergy and dermatitis.

Main Methods:

• Literature review of population studies on nickel sensitization.
• Analysis of data on nickel concentrations in consumer items and their relation to allergic reactions.
• Evaluation of exposure thresholds for eliciting nickel dermatitis.

Main Results:

• 11.1% of females and 2.2% of males in a Danish study were nickel-sensitized.
• Non-sensitizing nickel concentration suggested at 0.5 microgram/cm2/week for consumer items.
• Nickel dermatitis is unlikely below 0.1-1 microgram/cm2 (occluded) and 15 micrograms/cm2 (non-occluded).
• Highly sensitized individuals may react to very low concentrations (0.0075 microgram/cm2) on inflamed skin.

Conclusions:

• Most nickel allergy and dermatitis cases are preventable.
• Prevention is achievable without compromising quality of life or incurring societal economic costs.
• Further research is needed on the effects of repeated nickel exposures on normal skin.