Human skin burning

The world as we know it could not function without acids and bases. These chemical compounds are used extensively, from the chemical laboratory to the manufacturing industry. They are necessary for the proper functioning of the human body and for the health of the environment, too. Acids taste sour, break down metals, and react with bases. Without acids, soft drinks, lemonade, and tomato sauce would not taste the same way. Bases taste bitter, feel slippery, and react with acids. Without bases, cakes would be hard and flat, and laundry detergent would not clean. Both acids and bases can change certain vegetable substances a variety of different colors, and they can burn through human skin if not handled properly. Without acids and bases, we would not have dynamite, some heart medications, and fertilizers. On the other hand, without acids, we would not have damaging acid rain. And... 

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. ... 

Medical reports of acute human exposures (concentration unspecified) include moderate and severe skin burns, moderate eye burns and mild inhalation effects. Although acrylic acid is acutely irritating at sites of initial contact, it causes little systemic toxicity. The low systemic toxicity of acrylic acid is likely a consequence of its rapid and extensive metabolism to C02. ... 

Human subjects experienced irritation of the nose and throat after brief exposure to 10-20ppm. Workers complained of transient visual disturbances (haloes around lights) after exposure to the vapor for 8 hours, probably due to mild corneal edema, which usually cleared within 3 hours. The liquid is also capable of causing severe eye burns that may cause permanent visual impairment. Isopropylamine in both liquid and vapor forms is irritating to the skin and may cause skin burns repeated lesser exposures may result in dermatitis. ... 

A dilute solution buffered to pH 2.5 caused a moderate brief stinging sensation but no injury when dropped in the human eye. A 75% solution will cause severe skin burns. ... 

Little information exists on the toxicology of piperazine dihydrochloride in humans or in animals. Acute human exposures to the dust have reportedly resulted in irritation to the eyes, mild to moderate skin burns, and sensitization. Exposure levels and duration were not available. Occupational exposures have been associated with occasional cases of asthma. In one factory, several cases of asthma were precipitated by a time-weighted average (TWA) exposure of 1.2mg/m although there were brief exposure peaks of lOOmg/m or higher. There were no new cases noted in a workplace... 

Aminolevulinic acid (ALA HCl, Levulan Kerastick) is indicated for the treatment of nonhyperkeratotic actinic keratosis of the face and scalp. It has two components, an alcohol solution vehicle and ALA HCl as a dry solid. The two are mixed prior to application to the skin. When applied to human skin, ALA is metabolized to protoporphyrin, which accumulates and on exposure to visible light produces a photodynamic reaction that generates reactive oxygen species (ROS).The ROS produce cytotoxic effects that may explain therapeutic efficacy. Local burning and stinging of treated areas of skin due to photosensitization can occur. 

Fisher,14 discussing tear gases and their effect on human skin, remarked that CS Is a sensitizer and a primary Irritant capable of causing first- and second-degree burns and even ulcers if not washed off the skin. In experimentally sensitized subjects, CS elicited a skin response in one of nine when tested at 0.1%, but none reacted at 0.01Z.2/ Concentration is a factor in the elicitation of a skin response to a sensitizer, as well as an Irritant. 

As mentioned earlier, the stoppage of fast electrons generates x-rays, which are hazardous to human health. X-rays cause cell damage that can lead to cancer formation or genetic mutations. Even at low dosage, x-ray exposure can cause skin burning and general radiation syndrome. 

In 2000 Hamilton et al. reported that ATP in human skin elicits a dose-related pain response which is potentiated under conditions of hyperalgesia. The authors used iontophoresis to deliver ATP to the forearm skin of volunteers who rated the magnitude of the evoked pain on a visual analog scale. ATP consistently produced a modest burning pain, which began within 20 s. of starting iontophoresis and was maintained for several minutes. Persistent iontophoresis of ATP led to desensitization... 

Absorption of silver nitrate across intact skin has been demonstrated in guinea pigs and is similar to that of intact human skin (Wahlberg 1965). The amount absorbed was estimated to be approximately 1 % of the applied dose within 5 hours of exposure. Silver administered in the form of silver sulphadiazine cream was minimally absorbed through both the intact and burned skin of rats and distributed throughout the body (Sano et al. 1982). The absorption of silver increased through burned skin after blister removal. The authors did not determine the percentage of the applied dose that was absorbed (Sano et al. 1982). 

Frostbite occurs when human skin freezes. It is more likely to happen to the hands, feet, nose and ears, but any bit of skin exposed to severe cold temperatures for long periods of time can suffer from frostbite. The skin gets hard, pale, and cold, but it doesn t hurt once frozen. The pain comes when the skin begins to thaw and feeling returns to the body part. Tingling, burning pains, and red blisters are not uncommon. 

Burd, D.A. et al., Human skin and post-burn scar hyaluronan demonstration of the association with collagen and other proteins, Matrix, 9, 322, 1989. 

Acute dermal exposure of humans to chromium(VI) compounds causes skin burns. Necrosis and sloughing of the skin occurred in individuals at the site of application of a salve containing potassium chromate. Twelve of 31 people died as a result of infection of these areas (Brieger 1920). In another case, a man who slipped at work and plunged his arm into a vat of chromic acid had extensive bums and necrosis on his arm (Cason 1959). 

The impact of electromagnetic radiation, especially of UV radiation, on the human skin and on the eye may lead to severe adverse effects (see Fig. 2-4) including skin cancer, severe skin burning, conjunctivitis or cataract formation. Hence, appropriate protective measures must be considered while working with artificial radiant sources. This includes UV-blocking eyewear and face wear. Never look directly and unprotected at an operating UV or VUV lamp ... 

While capsaicinoids may have a vesicant effect, depending on length of exposure, in most cases it produces a burning sensation and mild erythema. Capsaicins cause erythema and burning pain without vesiculation when applied topically to human skin (Smith et al, 1970 Burnett, 1989 Watson et al, 1996 Herman et al, 1998). Skin blistering and rash may occur after chronic or prolonged capsaicin exposures (Morton, 1971). 

SAFETY PROFILE Moderately toxic by ingestion, subcutaneous, and intraperitoneal routes. A severe eye irritant. A human skin and severe eye irritant. Mutation data reported. Combustible when exposed to heat or flame can react with oxidizing materials. The powder burns rapidly in oxygen. To fight fire, use water, CO2, water spray or mist, dry chemical. When heated to decomposition it emits acrid smoke and irritating fumes. 

Caution. Fluorine presents some, though not an extreme, hazard because of its toxicity. It ignites combustible materials spontaneously and may start laboratory fires. Wa.ste fluorine from the reaction should be discharged into a hood, and the waste vent should not be close to materials which will burn. Fluorine in high concentration burns human skin. The burn seems to be caused at least as much by heat as by the hydrogen fluoride produced by the reaction. 

Dermatomed human skin Human SC and de-glycerinized dermatomed skins (Dutch Burns Society)... 

Dichlorobenzene has low acute toxicity. However, people exposed to high levels for relatively short periods of time potentially can develop malaise, nausea, vomiting, headaches, and irritation of eyes, respiratory tract, and the skin (burning sensation upon contact). Central nervous system (CNS) depression may occur at high concentrations that are extremely irritating to the eyes and nose. The TDLo in humans is 300 mg kg... 

Piperazine causes primary dermal irritation and skin burns at high concentrations. Piperazine also causes eye irritation in humans. 

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. 

The human skin serves as the body s first line of defense against biological and chemical attack. It is not, however, an armored plate. Rather, it is a permeable membrane that is vulnerable to attack by a large number of chemicals. It is subject to irritation and burning by chemicals and can also react to chemical allergens, as in allergic contact dermatitis. Respiratory sensitization can also ensue following dermal sensitization. 

Upon contact with human skin, selenium compounds have been reported to cause rashes, redness, heat, swelling, and pain. Brief, acute exposure of the eyes to selenium dioxide as a dust or fume in workplace air may result in burning, irritation, and tearing. However, only people who work in industries that process or use selenium or selenium compounds are likely to come into contact with levels high enough to cause eye irritation. 

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