Contact Dermatitis


All are true of irritant dermatitis by alkalis except


A. Atopic patients are predisposed to hand dermatitis by alkalis
B. Alkalis don’t cause deep injuries as they are not corrosives
C. Water glass, a caustic used for the preservation of eggs can cause hand eczema
D. Immediate application of a weak acid such as vinegar, lemon juice, or 0.5% hydrochloric acid solution will lessen their effects



Not true of injuries by acids is


A. Powerful acids are corrosive, whereas the weaker acids are astringent
B. Sulfuric and nitric acid burns are less deep and more liable to form blisters
C. Nitric acid or formic acid is used in assaults secondary to interpersonal conflicts
D. Hydrofluoric acid is one of the strongest inorganic acids, capable of dissolving glass



All are true of irritant dermatitis except


A. Airbag dermatitis is caused by sodium hydroxide, and sodium carbonate
B. Burns by capsaicin are immediately relieved by cold water
C. Tear gas dermatitis is caused by lacrimators such as chloroacetophenone
D. Sulfur mustard gas used in chemical warfare can cause toxic epidermal necrolysis



Oxalic acid burns are best characterized by


A. White eschar on the surface of the skin
B. Application of water to the exposed part will produce severe burns
C. Readily neutralized with 65% ethyl or isopropyl alcohol
D. Excision of affected skin down to the fascia should be accomplished rapidly



Not true of hydrocarbon irritant injuries is


A. Oils of the paraffin series are more irritating than those of the naphthalene series
B. Insoluble cutting oils are responsible for a follicular acneiform eruption
C. Soluble oils and synthetic fluids used in metalworking do not result in acne
D. Paraffin exposure leads to pustules, keratoses, and ulcerations



In short


Shale oil


Shale oil workers develop an erythematous, follicular eruption that eventually leads to keratoses, which may become the sites of carcinoma. It is estimated that 50% of shale oil workers have skin problems.
Petrolatum dermatitis may appear as a verrucous thickening of the skin caused by prolonged contact with impure petroleum jelly or, occasionally, lubricating oil.


Chloracne


Chlorinated compounds cause chloracne, there is a loss of sebaceous glands and the formation of cystic structures. Small, straw-colored follicular plugs and papules, develop on the malar crescent, retroauricular areas, earlobes, neck, shoulders, and scrotum.


Polychlorinated dibenzo-p-dioxins is responsible for inducing chloracne


Chloracne may persist for long periods because dioxin is stored in the liver and released slowly into the circulation.


Phenol -white eschar


Phenol (carbolic acid) is a protoplasmic poison that produces a white eschar on the surface of the skin. It can penetrate deep into the tissue. Phenol is readily neutralized with 65% ethyl or isopropyl alcohol.


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