Contact dermatitis, occupational exposures causing

Construction workers risk occupational contact dermatitis from exposure to irritants, chromate, cobalt, rubber and epoxy. Nickel allergy, however, is not often discussed in relation to construction work (Coenraads et al. 1984). In construction workers it is often found together with allergy to chromate and/or cobalt, and nickel in cement has been proposed as a cause. However, nickel in cement exists mainly as insoluble salts (Wahlberg et al. 1977 Goh et al. 1986). 

The most frequent causes of allergic contact dermatitis in the United States include plants (poison ivy, poison oak, and poison sumac), metallic salts, organic dyes, plastic resins, rubber additives, and germicides.74 The most common skin patch test allergens found to be positive in patients along with potential sources of exposure are shown in Table 32.1.75 In patients with occupational contact dermatitis who were skin patch tested, the common allergens included carba mix, thiuram mix, formaldehyde, epoxy resin, and nickel.76... 

Toxicology. Cobalt causes skin irritation, allergic contact dermatitis, and occupational asthma interstitial pulmonary fibrosis is associated with exposure to hard metal dust (tungsten and cobalt). 

MEKP has caused irritant dermatitis with direct contact only rarely has it caused allergic contact dermatitis from occupational exposure. ... 

Dermal Effects. Occupational exposure to airborne chromium compounds has been associated with effects on the nasal septum, such as ulceration and perforation. These studies are discussed in Section 2.2.1.2 on Respiratory Effects. Dermal exposure to chromium compounds can cause contact allergic dermatitis in sensitive individuals, which is discussed in Section 2.2.3.3. Skin burns, blisters, and skin ulcers, also known as chrome holes or chrome sores, are more likely associated with direct dermal contact with solutions of chromium compounds, but exposure of the skin to airborne fumes and mists of chromium compounds may contribute to these effects. 

Organomercurials have been a common cause of allergic contact dermatitis or rash (22) and even exfoliative dermatitis has been described (23). Some reagents for intra-cutaneous testing (tuberculin, etc.) may contain thiomersal, which can cause sensitization and thus elicit false-positive delayed-type skin reactions. Mercury compounds inhibit most lymphocyte functions (SEDA-21, 240). An early indicator of an immunological response to mercury exposure, for example in occupational medicine, appears to be a change in the lymphocyte count with a differential increase in T helper cells and a rise in the T helper/T suppressor ratio (24). 

Dermal and ocular exposures are the most common routes of exposure to captafol. Contact dermatitis has been reported after exposure to captafol. During occupational exposure, captafol has been reported to cause severe irritation of the respiratory tract, eye damage and other systemic effects. Oral ingestion of captafol is unlikely to cause acute poisoning. 

Exposure to Asteraceous plants may also result in the development of contact dermatitis. One Serbian study has indicated that it is not unusual to detect sensitization to chamomile (Chamomilla recutita), arnica (Arnica montana), tansy (Tanacetum vulgare), and feverfew (Tanacetum parthenium) (Jovanovic et al., 2004). Contact dermatitis, along with asthma and rhinitis, may also accompany occupational exposure to chamomile (Rudzki et al., 2003) and contact dermatitis to feverfew (Hausen, 1981). Similarly, chamomile in cosmetic products can also be a cause of dermatitis (Paulsen, 2002 Rycroft, 2003). Because chamomile-containing products, particularly in shampoos and other OTC products, are so widespread, the linkage to these types of adverse events are likely underreported. Also, use of royal jelly, a thick mixture of honey, pollen, and their allergens, has been associated with several cases of bronchospasm, and topical application of concentrated forms of bee pollen (propalis) to contact dermatitis (Perharic, 1993). Milk thistle has also been known to cause urticaria (De Smet, 2004). 

Contact dermatitis can occur from exposure to cement and has been considered an occupational hazard for construction workers (Turk and Rietschel 1993 Roto et al. 1996 Zachariae et al. 1996). The problem develops because chromium(VI)-con-taining residues from blast furnaces are incorporated into cement. Some countries add ferrous sulfate to cement to reduce the amount of soluble hexavalent chromate in the product (Turk and Rietschel 1993 Roto etal. 1996 Zachariae etal. 1996). In the UK, chromium and chromates accounted for 8.1% of the allergic contact dermatitis cases (Meyer et al. 2000). In Finland, chromium causes 5.6% of ACD, with tanners, cast concrete workers, leader goods workers, and metal plating/coating workers being at greatest risk (Kanerva et al. 2000). In Denmark, the chromium(VI) content of 35% of... 

There is no established evidence (epidemiological or experimental) for carcinogenicity caused by exposure to Cr(III) or Cr(0) compounds (113, 117). However, allergic contact dermatitis due to occupational exposure to Cr(lll) (primarily in the leather tanning industry) is relatively common (144—146). The safety of oral intake of Cr(III) in food supplements has also been questioned (Section IV.D) (5). A concern about the safety of the use of Cr(0) in stainless steel body implants (e.g., artificial joints or fracture fixation plates) was raised following at least one reported case of bone cancer caused by corrosion of the implant (147). In vitro studies have shown that the corrosion of Cr alloys in human semm leads to Cr(III) binding to serum proteins (148). Such corrosion can also release another possible carcinogen, Ni(II) (149). This problem should be overcome by the use of Ti alloys (free of Cr or Ni), which were introduced as an alternative 10-15 years ago (150). 

Trinitrotoluene (2,4,6-trinilrololueue, TNT [CAS 118-96-7]) Irritating upon direct contact. Stains tissues yellow. Causes sensitization dermatitis. Vapors irritating to the respiratory tract. May cause liver injury, methemoglobinemia (see p 261). Occupational overexposure associated with cataracts. Causes vasodilation, including coronary arteries. Headache and drop in blood pressure are common. Well absorbed by all routes. Tolerance to vasodilation can occur cessation of exposure may precipitate angina pectoris in pharmacologically dependent workers. See also nitrates, p 279. 

Allergic and irritant dermatitis (contact dermatitis) is overwhelmingly the most important cause of occupational skin diseases, which account for 15% to 20% of all reported occupational diseases. There is virtually no occupation or industry without potentitd exposure to the many diverse agents that cause allergic and irritant dermatitis. 

It is important to always consider the hazards of the chemicals you are using. Handling common salts or using solutions of innocuous salts or low concentrations of acids and bases is not very hazardous. Most solids encountered in introductory chemistry (but not all) don t pose much of a risk for skin exposure. Nevertheless, contacts with solid chemicals should be avoided or minimized. Furthermore, some solids encountered in advanced labs may pose potential for contact dermatitis. Contact dermatitis is the most common occupational medical condition—this can be caused by allowing skin to come in contact with some solids. 

Propionic acid derivatives Propionic acid derivatives, including ketoprofen and carpro-fen, can cause photosensitivity when used topically or systemically [9 ]. Occupational exposure can also result in photosensitivity. Consort contact dermatitis to such agents used topically is rare in the occupational setting, although it may occur when there is close physical contact with others [10 ]. 

Kiely C, Murphy G. Photoallergic contact dermatitis caused by occupational exposure to the canine non-steroidal antiinflammatory drug carprofen. Contact Dermatitis 2010 63(6) 364-5. 

Since use of gloves can sometimes cause accidents, and the substitution of noxious products by less aggressive substances is sometimes not possible for technical or economical reasons, skin-care products play an important role in the prevention of occupational contact dermatitis. Preventive skin care at the workplace may be divided into pre-exposure protection by protective creams, removal of irritants by mild cleaning agents, and enhancement of barrier-function generation by emollients or moisturisers. More details are given in Chap. 62, Barrier Creams/Emollients,... 

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