Dermatitis sensitization

Meime T. 1994. Quantitative aspects of nickel dermatitis Sensitization and eliciting threshold concentrations. Sci Total Environ 148 275-281. 

Human skin provides a barrier that protects the body from the physical, biological, and chemical environment. Skin, however, is also a permeable membrane through which xenobiotic chemicals may enter the body. Chemicals contacting the skin can also injure or burn the skin, cause dermatitis, sensitization, and other skin maladies and make the skin less capable of guarding against physical and biological insult. Lipophilic chemicals more easily permeate the skin than hydrophilic chemicals, but when mixed together, the lipophiles facilitate the absorption of hydrophiles. 

HEALTH SYMPTOMS Inhalation (coughing, increased mucous secretion, sore throat, breathing difficulty, upper respiratory tract irritation) skin contact (acid bums, dermatitis, sensitization, severe thermal bums caused by liquid) ingestion (sore throat, vomiting, diarrhea, cramps, abdominal pain). 

Allergic contact dermatitis Sensitization or allergic contact dermatitis is a delayed, immunologically mediated response to a chemical. Initial contact with the chemical does not appear to have any effect on the skin, but after a short delay (ca. 5 days) reexposure to the chemical causes an acute inflammatory reaction with an homogeneous rash. ... 

Epstein S (1958 b) Dermal contact dermatitis, sensitivity to rivanol and gentian violet. Dermatologica 117 287-296... 

Toxicology LD50 (oral, rat) 33,750 m g LDLo (IV, rat) 22 g/kg mod. toxic by IV route si. toxic by ing. skin and eye irritant contact dermatitis sensitization may cause hives TSCA listed Precaution Combustible exposed to heat or flames Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and irritating fumes... 

Dermal contact dermatitis. Sensitivity to Rivanol and gentian violet. Dermatologica (Basel) 117, 287—296 (1958). 

Irritation which is mediated by the immune system is toxicologically known as sensitization-, when the skin is the target organ, the term used is allergic contact dermatitis. Sensitization due to inhalation exposure is less common. Allergic contact dermatitis is also cdWcAcell-mediatedimmunity because the responsible structures are cells (rather than antibodies produced by cells) and/or delayed hypersensitivity because a period of induction (of the necessary cells) is required prior to expression of the irritant response. 

Repeated exposures to acryhc monomers can produce allergic dermatitis (or skin sensitization) resulting in rash, itching, or sweUing. After exposure to one monomer, this dermatitis may arise upon subsequent exposure to the same or even a different acryhc monomer. 

Hydrogen chloride in air can also be a phytotoxicant (88). Tomatoes, sugar beets, and fmit trees of the Pmnus family are sensitive to HCl in air. Exposure of concentrated hydrochloric acid to the skin can cause chemical bums or dermatitis. Whereas the irritation is noticed readily, the acid can be water flushed from the exposed area. Copious use of miming water is the only recommended safety procedure for any external exposure. Ingestion is seldom a problem because hydrochloric acid is a normal constituent of the stomach juices. If significant quantities are accidentally swallowed, it can be neutrali2ed by antacids. 

In humans, cases of dermatitis have been described after contact with DHBs. Combined exposure to hydroquinone and quinone airborne concentrations causes eye irritation, sensitivity to light, injury of the corneal epithelium, and visual disturbances (126). Cases with an appreciable loss of vision have occurred (127). Long-term exposure causes staining due to irritation or allergy of the conjunctiva and cornea and also opacities. Resorcinol and catechol are also irritants for eyes. 

Eye and Skin Contact. Some nickel salts and aqueous solutions of these salts, eg, the sulfate and chloride, may cause a primary irritant reaction of the eye and skin. The most common effect of dermal exposure to nickel is allergic contact dermatitis. Nickel dermatitis may occur in sensitized individuals following close and prolonged contact with nickel-containing solutions or metallic objects such as jewelry, particularly pierced earrings. It is estimated that 8—15% of the female human population and 0.2—2% of the male human population is nickel-sensitized (125). 

Although most nickel sensitization results from nonoccupational exposures, nickel dermatitis was historically a problem in workplaces where there was a high risk of continuous contact with soluble nickel, eg, in electroplating (qv) shops. Improved personal and industrial hygiene has largely eliminated this problem. However, there are a few occupations involving wet nickel work, particularly where detergents faciUtate the penetration of skin by nickel, where hand eczema may occur (126). 

Uncured resins are skin sensitizers and contact should be avoided, as weU as breathing the vapor, mist, or dust. Novolak-based pulverized products generally contain hexamethylenetetramine, which may cause rashes and dermatitis. PhenoHc molding compounds and pulverized phenoHc adhesives must be controUed as potentially explosive dusts. In addition, they contain irritating or toxic additives. 

Phosphoms(V) sulfide is a mild skin irritant and may cause dermatitis in sensitive individuals. The primary health ha2ard results from the Hberation of hydrogen sulfide after contact with moisture. Contact with moisture also forms phosphoric acid. A secondary ha2ard is the formation of sulfur dioxide when phosphoms(V) sulfide bums. The oral LD q of in rats is 389 mg/kg the OSHA standard time-weighted average (TWA) is 1 mg /m (33). 

The first -PDA antiozonants were low molecular weight -diaLkyl-/)-PDAs which caused skin irritations. Current higher molecular weight -dialkyl or A/-alkyl-AT-aryl derivatives are not primary skin irritants. A notable exception is A/-(I-methylethyl)-A7-phenyl-/)-PDA, which causes dermatitis. However, since some individuals are more sensitive than others, antiozonants should always be handled with care (46). When skin contact does occur, the affected area should be washed with mild soap and water. In case of eye contact, flush weU with water. Inhalation of mbber chemicals should be avoided, and respiratory equipment should be used in dusty areas. 

SENSITIZATION DERMATITIS Inflammation of the skin due to an allergic reaction to a sensitizer. 

Platinum compounds Hydrosilation cross-linking of silicone polymers Hydrogenation, isomerization and hydroformylation of alkenes Automobile exhaust catalyst Sensitization dermatitis... 

Health Hazards Information - Recommended Personal Protective Equipment Data not available Symptoms Following Exposure May cause dermatitis in sensitive individuals (humans) General Treotmera for Exposure Data not available Toxicity by Inhalation (Threshold Limit Value) Data not available Short-Term InhalationLinuts Data not available Toxicity by Ingestion GradeO, LD o above 15 g/kg Late Toxicity Data not available Vapor (Gas) Irritam Characteristics Data not available Liquid or Solid Irritant Characteristics Data not available Odor Threshold Data not available. 

Allergic contact dermatitis Skin condition that occurs in response to exposure to sensitizing material. It is characterized by redness, swelling and cracking and, sometimes more severe reactions involving the entire immune system. 

Brendlinger, D. L. and Tarsitano, J. J. Generalized Dermatitis due to Sensitivity to a Chrome-Cobalt Removable Partial Denture , Journal of the American Dental Association, 81, 392-394 (1970)... 

Exposure to Ni may cause dermatitis (Ni itch) in sensitive individuals. Ingestion of large amts (even l-3mg/kg of body wt) causes nausea, vomiting, diarrhea, depression of the central nervous system. Its health hazard is, however, considered slight. The M.A.C. (max allowable... 

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