Chromium airborne

In an industrial plant in which the airborne chromic acid concentrations measured from 0.18 to 1.4mg/m/ moderate irritation of the nasal septum and turbinates was observed after 2 weeks of exposure, ulceration of the septum was present after 4 weeks, and there was perforation of the septum after 8 weeks. A worker exposed to an unmeasured concentration of chromic acid mist for 5 years developed jaundice and was found to be excreting significant amounts of chromium liver function was mildly to moderately impaired in four other workers with high urinary chromium excretion. ... 

Wear nitrile rubber gloves, laboratory coat, and protection. To reduce risk of forming airborne dust, cover spill with a 1 1 1 mixture by weight of sodium carbonate or calcium carbonate, clay cat litter (bentonite), and sand. Scoop the solid into a container and transport to the fume hood. Slowly, while stirring, add the solid to household bleach (50 mL/g of chromium hexacarbonyl). Allow the solid to settle, decant the liquid to the drain with at least 50 times its volume of water. Dry and package the solid for disposal in accordance with local regulations.5,6... 

Hence, above a certain threshold loading of about 1 atom nm-2, chromium evaporates from the catalyst during calcination. If this occurs in a porous catalyst, the airborne species may deposit somewhere else and anchor subsequently to the support. Hence, gas-phase transport may be expected to play an important role in the redispersion of chromium species through the calcination of a high-surface area polymerization catalyst. 

Occupational exposure to chromium(III) or chromium(O) does not appear to be associated with renal effects. No renal impairment based on urinary albumin, retinol binding protein, and renal tubular antigens was found in 236 workers employed in the ferrochromium production industry where ferrochromite is reduced with coke, bauxite, and quartzite. The mean airborne concentration of chromium in various sample locations was 0.075 mg chromium(III)/m3 chromium(VI) was below the detection limit of 0.001 mg chromium(VI)/m3 at all locations (Foa et al. 1988). Workers employed in an alloy steel plant with a mean exposure of 7 years to metallic chromium at 0.61 mg chromium(0)/m3 and to other metals had normal urinary levels of total protein and p2-microglobulin, enzyme activities of alanine-aminopeptidase, N-acetyl-P-D-glucosaminidase, gammaglutamyl-transpeptidase, and P-galactosi-dase (Triebig et al. 1987). In boilermakers exposed to chromium(O), no increase in urinary levels of... 

Ocular Effects. Effects on the eyes due to direct contact of the eyes with airborne mists, dusts, or aerosols or chromium compounds are described in Section 2.2.3.2. An extensive epidemiological survey was conducted of housewives who lived in an area of Tokyo, Japan, in which contamination from chromium slag at a construction site was discovered in 1973. The housewives included in the study were those who lived in the area from 1978 to 1988, and controls included housewives who lived in uncontaminated areas. Questionnaires, physical examinations, and clinical tests were conducted annually. Higher incidences of subjective complaints of eye irritation were reported by the exposed population than the control population in the early years of the survey, but in later years the difference between the two groups became progressively less (Greater Tokyo Bureau of Hygiene 1989). 

Respiratory Effects. Occupational exposure to chromium compounds results in direct contact of mucocutaneous tissue, such as nasal and pharyngeal epithelium, due to inhalation of airborne dust and mists of these compounds. Such exposures have led to nose and throat irritation and nasal septum perforation. Because exposure is to airborne chromium, studies noting these effects are described in Section 2.2.1.2. 

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. 

Although skin contact with chromate salts may cause rashes, untreated ulcers or sores (also called chrome holes) on the skin can be a major problem because they can deeply penetrate the skin with prolonged exposure. For example, in an early case of a tannery worker, the penetration extended into the joint, necessitating amputation of the finger (Da Costa et al. 1916). However, chrome sores heal if exposure is discontinued, leaving a scar. Chrome sores are more often associated with occupational exposure to chromium(VI) compounds. Although chrome sores are more likely associated with direct dermal contact with solutions of chromates, exposure of the skin to airborne fumes and mists of... 

A list of industries that may be sources of chromium exposure is given in Table 5-5. For most occupations, exposure is due to both chromium(III) and chromium(VI) present as soluble and insoluble fractions. However, exceptions include the tanning industry, where exposure is mostly from soluble chromium(in) and the plating industry, where exposure is due to soluble chromium(VI). The typical concentration ranges of airborne chromium(VI) to which workers in these industries were exposed during an average of 5-20 years of employment were chromate production, 100-500 pg/m3 stainless steel welding,... 

Bell RW, Hipfner JC. 1997. Airborne hexavalent chromium in Southwestern Ontario. J Air Waste Manage Assoc 47 905-910. 

Falerios M, Schild K, Sheehan P,et al. 1992. Airborne concentrations of trivalent and hexavalent chromium from contaminated soils at unpaved and partially paved commercial/industrial sites. J Air Waste Manage Assoc 42 40-48. 

Finley BL, Mayhall DA. 1994. Airborne concentrations of chromium due to contaminated interior building surfaces. Appl Occup Hyg 9 433-441. 

Finley B, Fehling K, Falerios M, et al. 1993. Field validation for sampling and analysis of airborne hexavalent chromium. Appl Occup Environ Hyg 8(3) 191-200. 

Finley BL, Kerger BD, Dodge DG, et al. 1996a. Assessment of airborne hexavalent chromium in the home following use of contaminated tapwater. J Expo Anal Environ Epidemiol 6(2)229-245. 

Kuo H-W, Lai J-S, Lin T-I. 1997b. Concentration and size distribution of airborne hexavalent chromium in electroplating factories. Am Ind Hyg Assoc J 58 29-32. 

Sheehan P, Ricks R, Ripple S, Paustenbach D. 1992. Field evaluation of a sampling and analytical method for environmental levels of airborne hexavalent chromium. Am Ind Hyg Assoc J 53(l) 57-68. 

Biological, chemical, and physical effects of airborne metals are a direct function of particle size, concentration, and composition. The major parameter governing the significance of natural and anthropogenic emissions of environmentally important metals is particle size. Metals associated with fine particulates are of concern particles larger than about 3-fjim aerodynamic equivalent diameter are minimally respirable, are ineffective in atmospheric interactions, and have a short air residence time. Seventeen environmentally important metals are identified arsenic, beryllium, cadmium, chromium, copper, iron, mercury, magnesium, manganese, nickel, lead, antimony, selenium, tin, vanadium, and zinc. This report reviews the major sources of these metals with emphasis on fine particulate emissions. 

Although data are incomplete, the major stationary emission sources for many of the environmentally important metals are given in Table VI. Smelters/metallurgical processes are predominant sources of airborne cadmium, chromium, copper, and manganese. Coal and oil combustion. 

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