3,4,3',4'-Tetrachloro azoxybenzene and azobenzene: potent inducers of aryl hydrocarbon hydroxylase.

Two unwanted contaminants, 3,4,3',4'-tetrachloroazoxybenzene (TCAOB) and 3,4,3',4'-tetrachloroazobenzene (TCAB), formed in the commercial synthesis of 3,4-dichloroaniline or of herbicides made from 3,4-dichloroaniline, were responsible for three outbreaks of acne among chemical workers. TCAOB and TCAB are approximately isosteric to 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran, two well-known contaminants that cause acne. All four of these agents are potent inducers of hepatic aryl hydrocarbon hydroxylase activity and compete for stereospecific binding sites in the hepatic cytosol, which are thought to be the receptor sites for the induction of this enzyme. Among the chlorinated azoxy and azobenzenes, the potency of a congener to induce aryl hydrocarbon hydroxylase activity correlates with its binding affinity for the hepatic cytosol specific binding sites and its capacity to induce acne; this relation between structure and activity parallels that observed for the chlorinated dibenzo-p-dioxins and dibenzofurans.

Dermatitis among workers cleaning the Sacramento River after a chemical spill--California, 1991.

On July 14, 1991, a train tanker car derailed in northern California, spilling 19,000 gallons of the soil fumigant metam sodium (sodium methyldithiocarbamate) into the Sacramento River north of Redding (Figure 1). The major breakdown product of metam sodium, methylisothiocyanate (MITC), is a known skin irritant at high concentrations (greater than 1%). By July 21, the concentration of MITC in the river, at multiple test sites, measured 20-40 parts per billion (0.01%). On August 6, Shasta County health officials notified the California Department of Health Services (CDHS) of an outbreak of dermatitis among Shasta County jail inmates and crew leaders who had assisted in removing dead fish from the river on July 21-22 in greater than 100 F (greater than 38 C) ambient temperature.

Occupational and environmental health hazards in the plastics industry.

A brief description of the potential occupational health hazards encountered in the manufacture of plastics (polymers) is given. In general, these hazards are due to the monomers used to make the various plastics, to unreacted monomer contained within the finished products, and to the fillers, stabilizers, pigments, inhibitors, and initiators used in fabricating the finished products. They run the gamut from angiosarcomas of the liver due to vinyl chloride, to dermatitis and asthma-like reactions due to the initiators used with epoxy resins.

Contact dermatitis from cyanide plating solutions.

Two cases of contact dermatitis from electroplating solutions were attributed to irritation from cyanide salts. Both demonstrated similar clinical features. In neither could concomitant contact allergy to other constituents of the plating solutions be demonstrated. In one case, irritation could not be attributed to the alkalinity of the plating solution. Contact dermatitis from cyanide plating solutions may be associated with systemic symptoms, since cyanide is rapidly absorbed through the skin. Poor handling and hygiene techniques in the workplace should be corrected immediately.

Allergic contact dermatitis from anaerobic acrylic sealants.

Three patients employed in electronic assembly operations had allergic contact dermatitis to polyethylene glycol (PEG) dimethacrylate, found in an anaerobic sealant. Clinical features in all three cases consisted of eczema localized predominantly on the distal parts of the fingers and the palmar aspects of fingertips; onycholysis developed in one patient. No cross reactions to methyl methacrylate were observed on patch testing. Guinea pig maximization testing with both the commercially available sealant and the active resin demonstrated that PEG dimethacrylate is a moderate skin sensitizer.

Contact allergy to aziridine paint hardener.

A painter experienced an extensive dermatitis when exposed to a paint primer (undercoating) used to protect wood siding. The primer was an acrylic emulsion with a polyfunctional aziridine added as a self-curing cross-linker or hardener. The polyfunctional aziridine cross-linker was made by reacting propyleneimine with a polyfunctional acrylate, trimethylolpropane triacrylate (TMPTA). Our patient reacted to the cross-linker and also reacted to TMPTA, which is present in excess in the cross-linker. He also cross-reacted to pentaerythritol triacrylate (PETA). Both TMPTA and PETA can be used in the production of aziridine hardeners and both are well known as sensitizers in radiation-dried acrylic printing inks and coatings.

Sensitivity to the weed killer DNA-nitralin and cross-sensitivity to dinitrochlorobenzene.

A man, with a dermatitis acquired while working in a factory producing a weed killer, showed sensitivity to 4-methylsulfonyl 2,6-dinitro-N,N-dipropylaniline (DNA-nitralin) and its precursor, 4-chloro 3,-5-dinitrophenylmethyl sulfone (DNC), and cross-sensitivity to dinitrochlorobenzene (DNCB). Sensitization capacities of DNA-nitralin and DNC compared with DNCB, and cross-sensitizations among 11 dinitrobenzene derivatives, including DNA-nitralin, DNC, and DNCB, were studied in guinea pigs. We found that the order of potency was DNCB, DNC, and DNA-nitralin for the sensitization capacity, and that cross-sensitizations may occur among DNCB, DNC, DNA-nitralin, and dinitrofluorobenzene, in comparatively high incidence.

Persistent photosensitivity following occupational exposure to epoxy resin.

Persistent photosensitivity developed in eight men following occupational exposure to hot epoxy resin fumes. The condition was limited to sites the resin contacted. Small doses of ultraviolet-A light (2 to 5 joules/sq cm) evoked abnormal reactions consisting of erythema, edema, and papules in the clinically involved skin. Positive photopatch tests to epoxy resin were observed in four subjects, and to 4, 4'-isopropylidenediphenol (Bisphenol A) in all. The photosensitivity is most probably due to photocontact allergy to 4,4'-isopropylidenediphenol or to a closely related chemical.

Handwashing in Finland.

To prevent skin problems we have recommended in Finland that hospital personnel should avoid soap or other detergents for handwashing and instead use alcoholic preparations containing emollients such as 2% glycerol. Alcohol with emollient disinfection is used frequently in hospitals and it causes fewer complaints of skin dryness than washing with soap. However, there are still members of staff who have hand skin problems. Our studies conducted during winter have shown that when these persons used emulsion for hand cleansing, instead of washing with soap, skin deterioration was much less, allowing alcoholic disinfection of the hands whenever necessary, without impairment of the disinfecting effect of alcohol.

Environment and the skin.

The skin is an important organ of defense adaptation and a portal of entry for xenobiotics. It is vulnerable to physical, chemical, and biologic agents and capable of expressing responses to these agents in a variety of pathologic patterns. These patterns are characterized by morphologic and functional features which are elicited by careful examination and test procedures. Cutaneous cancer may result from exposure to nonionizing as well as ionizing radiation, to specific identifiable chemical hazards, and may be enhanced by trauma. Cutaneous hazards of chemical sources are largely found in the workplace and among consumer products, including drugs and toilet goods. Environmental skin diseases and injuries are preventable. Prior to use assessment for safety and for possible risks from exposure to an agent, product, or process is of primary importance in the prevention and control of environmental skin disease and injury.

Dogger bank itch. 4. An eczema-causing sulfoxonium ion from the marine animal, Alcyonidium gelatinosum [Bryozoa].

Repeated exposure to the marine bryozoan, Alcyonidium gelatinosum, frequently provokes an eczematous allergic contact dermatitis known as the "Dogger Bank Itch". The dermatitis, representing a severe occupational disease, is especially widely distributed among trawlermen working in the Dogger Bank area in the North Sea. The allergy is shown to belong to the type of cell-mediated hypersensitivity. The hapten has been identified as the (2-hydroxyethyl)dimethylsulfoxonium ion. The isolation, structure determination and synthesis are discussed.

Evaluation of the influence of epoxide resins and their hardeners on the female body. I. Skin tests.

Skin tests of hypersensitivity were performed in 175 women and 16 men having direct contact during work with epoxide resinsand their hardeners. The tests were applied for 24 hours, and results were recorded after 24, 48 and 72 hours. The percentages of positive skin tests and numbers of skin lesions were found to increase with time of employment in contact with epoxide resins and their hardeners.

Idiopathic pigmentation of the hands. Professional exogenous ochronosis? A new entity?

A case of ochronosis-like pigmentation of the hands is described. The following criteria were fulfilled: (1) presence of blue to black spots confined to the hands: (2) pitch-black macroscopic appearance of the biopsy specimen; (3) abundance of granular material in the whole connective structures on microscopic examination of an unstained specimen just mounted on a slide; (4) numerous pigmented granules in the elastic and collagen fibers: (5) no family history, abnormal coloration of the urine, taking of drugs, or rheumatism; (6) onset in a manual worker exposed to benzenic substances. This seems to be a new entity, probably a variant of exogenous ochronosis produced by professional contacts with some agents and perhaps a professional benzenic ochronosis.

Is it possible to work with pao ferro (Machaerium scleroxylum, Tul.)?

Pao ferro (Machaerium scleroxylum), used as a rosewood substitute, is a strong sensitizer capable of causing acute outbreaks of allergic and irritant dermatitis in workers not previously exposed to it. This, however, has not prevented furniture factories from using the product. Apparently, most workers develop tolerance to the wood.

Contact dermatitis caused by intermediate products in the manufacture of clenbuterol, ranitidine base, and ranitidine hydrochloride.

Clenbuterol, a beta antagonist, and ranitidine, a histamine-receptor antagonist, were associated with contact dermatitis in a chemist. The allergen in the former was an intermediate in the synthesis called beta. In the latter, intermediates and the finished base and hydrochloride were responsible.

Allergic contact dermatitis from safety clothes and individual protective devices.

Safety clothing and individual protective devices may induce contact dermatitis. Typical clinical patterns cannot always be found. Patch testing must be performed with articles actually used and with specific allergens. In some cases, it is necessary to analyze chemically the article itself.

Immediate contact hypersensitivity to acrylic acid.

A chemical worker developed acute generalized urticaria after working with acrylate compounds in a laboratory. Immediate-hypersensitivity testing to acrylic acid yielded a severe local reaction. Testing with other acrylate compounds was negative. Re-exposure in the work-place to vapors of acrylic acid resulted in generalized urticaria. With the cooperation of the employer, the patient moved to a marketing job with no contact with acrylic acid and has remained free of urticaria since.

Cosmetics and contact dermatitis.

A complete work-up of most patients with cosmetic allergies can be performed satisfactorily in a dermatologist's office without expensive equipment. After taking a complete history and performing a thorough examination, a biopsy is seldom required. Examine all the patient's cosmetics, eliminate the strong irritants, and proceed with product patch testing. Patch testing with the AAD allergen test tray at the same time is frequently helpful. When results are doubtful or do not fit with the information obtained from the history and examination, supplemental provocative use tests often clarify what information is clinically relevant. Patch testing with ingredients that dermatologists have obtained from cosmetic manufacturers or other sources often provides a helpful, definitive answer for the patient. Always provide the patient with information about cross-reactions and the official name of the allergen as it will appear on a cosmetic label to prevent recurrences.

Allergic contact dermatitis to ethylenediamine. A continuing problem.

Ethylenediamine would be an infrequent sensitizer if it were not present in a widely prescribed topical corticosteroid preparation that is applied to inflamed skin. Occupational allergic contact dermatitis to ethylenediamine is not common. The educational efforts of American dermatologists such as Dr. Alex Fisher have helped lead to the deletion of ethylenediamine from Mycolog cream. It is unfortunate that the same pharmaceutical company continues to use ethylenediamine in its products in other countries, as the continued popularity of these creams may allow ethylenediamine to remain a common sensitizer in some areas, particularly where inflammatory skin conditions are treated predominantly by nondermatologists.

Occupational allergic contact dermatitis to airborne nitrofurazone.

Allergic contact dermatitis to nitrofurazone has been reported from Europe and elsewhere from the use of eyedrops and topical ointments, and the drug in some livestock feeds and veterinary medications has caused a few cases of allergic contact dermatitis in humans. The authors report what appears to be the first case of contact dermatitis from airborne nitrofurazone secondary to a powdered aquarium water additive.