Acute delayed irritant contact dermatitis

Maneb or mancozeb. Maneb and mancozeb have been found to cause allergic contact dermatitis, a delayed (type IV immune system response) hypersensitivity reaction. After sensitivity to a particular allergen develops, subsequent contact to minute doses of the antigen elicits an acute response. While allergic and irritant contact dermatitis usually have indistinguishable clinical characteristics, the former reaction is a true allergy whereas the latter reaction is one whose intensity is proportional to the dose applied (Rice and Cohen... 

CN may cause primary irritant dermatitis or allergic contact dermatitis by delayed hypersensitivity. After sensitization, acute exposure to CN causes itching, erythema, edema, vesiculation, purpura, and necrosis.28 Jolly and Carpenter reported that an accidental discharge of a pen gun resulted in erythema and edema 24 h later the patient had been exposed to CN 5 yr earlier. Queen and Stander reported severe reactions to CN 17 yr after a first exposure to the agent. 

Highly toxic exhibits acute, delayed, and chronic toxicity symptoms include nausea, vomiting, weakness, somnolence, excitement, and muscle contraction causes dermatitis and irritation on skin contact a stimulant to central nervous system, producing convulsions can cause adverse reproductive effects no evidence of carcinogenicity in rats and mice oral LD50 value (mice) 7.5 mg/kg exposure limit PEL/TLV-TWA (skin) 0.1 mg/m (OSHA ACGlH) RCRA Waste Number P050 US EPA listed extremely hazardous substance. 

Acute ICD develops when the skin is exposed to a strong irritant or caustic chemical. Usually, this happens as an accident at work or in special emergency situations. The irritant reaction reaches its peak quickly, then starts to heal this is called the decrescendo phenomenon. Because the lag time is short (usually minutes to hours after exposure) and the association between exposure and skin symptoms is usually clear, the diagnosis is easy in most cases. It may become difficult when the patient was unaware of an exposure. Acute ACD has to be considered as differential diagnosis and is caused by a delayed sensitisation reaction 24-48 h after allergen contact, symptoms appear. This type of contact dermatitis is... 

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