TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 2915. POTENTIAL FOR HUMAN EXPOSUREPacyna 1988). However, land erosion, a natural source of chromium in water, was not included in theNriagu and Pacyna (1988) estimation of chromium contributions to the aquatic environment.5.2.3 SoilAccording to the Toxics Release Inventory, in 1997, the estimated releases of chromium of30,862,235 pounds (13,999,110 kg) to soil from 3,391 large processing facilities accounted for about94.1% of total environmental releases (TRI97 1999). An additional 1,131,559 pounds (513,275 kg) ofchromium, amounting to 3.4% of the total environmental release, was injected underground. Table 5-2lists the amounts released from facilities. The TRI data should be used with caution, however, since onlycertain types of facilities are required to report. This is not an exhaustive list.Total chromium has been identified in 939 soil and 472 sediment samples collected from 1,036 NPLhazardous waste sites where it was detected in some environmental media (HazDat 2000).Chromium(VI) has been identified in 59 soil and 22 sediment samples collected from 120 NPL hazardouswaste sites where it was detected in some environmental media (HazDat 2000).On a worldwide basis, the disposal of commercial products that contain chromium may be the largestcontributor, accounting for .51% of the total chromium released to soil (Nriagu and Pacyna 1988). Othersignificant sources of chromium release into soil include the disposal of coal fly ash and bottom fly ashfrom electric utilities and other industries (33.1%), agricultural and food wastes (5.3%), animal wastes(3.9%), and atmospheric fallout (2.4%) (Nriagu and Pacyna 1988). Solid wastes from metalmanufacturing constituted