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Updated: Jun 23, 2026
08:25
Contact Hypersensitivity as a Murine Model of Allergic Contact Dermatitis
Published on: September 26, 2022
[Contact dermatitis to elemental mercury with distant lesion]
Eduardo Mello De Capitani1, Elemir Macedo de Souza, Ronan José Vieira
1Centro de Controle de Intoxicações, Hospital de Clínicas, Universidade Estadual de Campinas, São Paulo, SP, Brazil. capitani@fcm.unicamp.br
Anais Brasileiros De Dermatologia
|April 21, 2009
Summary
Direct skin contact with elemental mercury can cause severe contact dermatitis. This case highlights the potential for significant dermal absorption and systemic effects, emphasizing the need for caution.
Area of Science:
- Toxicology
- Dermatology
- Environmental Health
Background:
- Elemental mercury exposure can occur through various routes.
- Dermal absorption of elemental mercury is a less commonly emphasized exposure pathway compared to inhalation.
Observation:
- A patient presented with severe contact dermatitis on the leg and foot after direct contact with elemental mercury.
- The dermatitis manifested as erythema, edema, vesicles, and progressed to necrotic plaques.
- Distant lesions appeared on the forearm, chest, and abdomen, suggesting systemic spread.
Findings:
- Urinary mercury levels confirmed significant dermal absorption (5.9 microg/L at 36h, rising to 19.6 microg/L one week later).
- The clinical presentation and elevated mercury levels indicate that elemental mercury can be absorbed through intact skin, causing local and systemic effects.
Implications:
- Healthcare providers should consider elemental mercury exposure in patients presenting with unexplained dermatitis, especially in occupational or environmental settings.
- Prompt recognition and management of elemental mercury exposure are crucial to prevent severe dermal and potential systemic toxicity.
- This case underscores the importance of protective measures to prevent skin contact with elemental mercury.
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