Children playing in areas where the slag was used as fill might also have been exposed through skin contact with chromium-contaminated dust, dirt, and puddles and /or ingestion of contaminated soil. In soil and roadways, these particles might have been eroded by wind and foot traffic and carried as chromium-laden dust into homes and workplaces. Chromium compounds leached by rainwater could have migrated through cracks in soil, asphalt roadways, and masonry walls, forming high-content chromium crystals on their surfaces. Wind erosion of the soil could have made slag particles airborne, increasing the opportunity for inhalation of chromium. Ĭommunity exposure from this fill occurred in a variety of ways. Persons living or working in the vicinity of the sites may have been exposed through inhalation, ingestion, or skin contact with contaminated soils and dusts. Ĭhromium waste slag containing potentially hazardous levels of Cr(VI) compounds was used as fill material at more than 160 residential, industrial, and recreational sites. Total chromium has been identified in 939 soil and 472 sediment samples collected from 1,036 National Priority Lists (NPL) hazardous waste sites. Īccording to the Toxics Release Inventory, in 1997 the estimated releases of chromium was 30,862,235 pounds to soil from 3,391 large processing facilities accounted for about 94.1% of total environmental releases. Forty-eight crossbreed Red Angus Nellore, with body weight of approximately 200☑4 kg and 10 months old, were used. However, the exact nature of such atmospheric reactions has not been studied extensively. The aim of this study was to evaluate organic sources of chromium and the level of inclusion of these sources on the growth performance and rumen fermentation of Nellore Angus crossbred steers with low protein diets. Cr(VI) in the air eventually reacts with dust particles or other pollutants to form Cr(III). Ĭr(III) in the air does not undergo any reaction. In contrast, chrome-plating sources are estimated to contribute 700 metric tons of chromium per year to atmospheric pollution, 100% of which is believed to be Cr(VI). Ĭoal and oil combustion contribute an estimated 1,723 metric tons of chromium per year in atmospheric emissions however, only 0.2% of this chromium is Cr(VI). The estimates of atmospheric chromium emissions in 19 in the Los Angeles, CA and Houston, TX areas indicate that emissions from stationary fuel combustion are about 46-47% of the total, and emissions from the metal industry range from 26 to 45% of the total. According to the Toxics Release Inventory, in 1997, the estimated releases of chromium were 706,204 pounds to the air from 3,391 large processing facilities which accounted for about 2.2% of total environmental releases.Ĭr(III) and Cr(VI) are released to the environment primarily from stationary point sources (facilities that are identified individually by name and location) resulting from human activities.
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