Irritants epidermal damage

Table 6. Epidermal damage observed in relation to various irritants (from Lachapelle 1995a)...

Exposure to high concentrations may cause tracheobronchitis and pulmonary edema. The irritation threshold in humans is 0.2 5-0.5 ppm, and concentrations above Ippm are extremely irritating to all mucous membranes within 5 minutes. Fatalities have been reported at levels as low as 10ppm, and 150 ppm was lethal after 10 minutes. The violent irritant effect usually prevents chronic toxicity in humans. Skin contact causes irritation, burns, and epidermal necrosis." Eye splashes cause corneal damage, palpebral edema, blepharoconjunctivitis, and fibrinous or purulent discharge. ... 

Liquid splashes to the eye can cause corneal damage and exposures to concentrations of 0.25 ppm may cause eye irritation, lacrimation, conjunctivitis, lid edema, fibrinous or purulent discharge, and corneal injury. Splashes to the skin can result in dermal irritation, edema, and, in some cases, epidermal necrosis. 

Toxicity. Mineral oils produce slight-to-moderate irritation by standard rabbit skin irritation tests (Beck et al., 1982 Mayhew et al., 1985). Repeated applications of mineral oils to skin over a week resulted in epidermal hyperplasia, hyperkeratosis, and depilation C14-C19 hydrocarbons caused more damage than C21-C23 hydrocarbons (Hoekstra and Phillips, 1963). 

Green tea and its constituents have been shown to protect skin from irritation caused by radiation as well as chemicals. EGCG has been shown to prevent skin damage caused by UVA radiation and 12-0-tetradecanoylphorbol-13-acetate (TPA) application through inhibition of NF-kB DNA binding and expression of MAP kinase and Cox-2 Psoriasis is an inflammatory skin disease in which there is hyperproliferation and improper differentiation of epidermal keratinocytes. Green tea polyphenols have been shown to alleviate symptoms of psoriasis in mice. ... 

Barany E et al. have studied the influence of stearic acid and several stearates, as emulsifiers in eream, on normal as well as on irritated skin [3]. Their results highlighted the possibility of absorption of these emulsifiers into the lipid bilayer, which increased trans-epidermal water loss (TEWL) in normal skin and decreased TEWL in damaged skin. 

Argyris TS (1985) Promotion of epidermal carcinogenesis by repeated damage to mouse skin. Am J Ind Med 8 329-337 Baran R, Tosti A (1993) Occupational acro-osteolysis in a guitar player. Acta Derm Venereol 73 64-65 Bruynzeel DP, de Boer EM (1996) Compromised skin. In van der Valk P, Maibach HI (eds) The irritant contact dermatitis syndrome. CRC Press, Boca Raton, pp 283-287 Burton JL (1992) Eczema, lichenification, prurigo and erythroderma. In Champion RH, Burton, JL, Ebling FJG (eds) Textbook of dermatology. Blackwell Scientific Publications, London, pp 537-588... 

Soldiers, by the nature of their profession, are at increased risk of mechanical skin damage. Friction blisters of the extremities are common (Hoeffler 1975) Knapik et al. (1992) reported that 69% of 335 soldiers participating in a maximal-effort road march developed foot blisters. Chronic or intermittent low-intensity irritation induces epidermal thickening, and strong acids (sulfuric, hydrochloric) and alkalis may cause chemical cauterization on contact with the skin (Shaposhnikov 1973 Naidenov 1980). 

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