Second Quarter 2006
INL Quarterly Site Environmental Report
Return to Index
Another potential pathway for contaminants to reach humans is through the food chain. The ESER Program samples multiple agricultural products and game animals from around the INL Site and Southeast Idaho. Specifically, milk, wheat, potatoes, garden lettuce, sheep, big game, doves and waterfowl are sampled. Milk is sampled throughout the year and large game animals are sampled whenever available. Sheep are sampled during the second quarter. Lettuce, wheat and waterfowl are sampled during the third quarter, while potatoes are collected during the fourth quarter. See Table A-1, Appendix A, for more details on agricultural product and wildlife sampling. This section discusses results from milk, sheep, and large game animals sampled during the second quarter of 2006.
Milk samples were collected weekly in Ucon and monthly at nine other
locations around the INL Site (Figure 12) during the second quarter of 2006.
All samples were analyzed for gamma emitting radionuclides. Samples are
analyzed for 90Sr and tritium during the second and fourth
Cesium-137 was detected in one of the samples, collected at Moreland in June, during the second quarter. Iodine-131 was not detected in any sample. Data for 131I and 137Cs in milk samples are listed in Appendix C, Table C-8.
Certain areas of the INL are open to grazing under lease agreements managed by the Bureau of Land Management (Figure 13). Every year ESER Program personnel collect samples of sheep that have grazed on these leased areas, either just before or shortly after the sheep leave the INL. This occurs during the second quarter of the year. For the calendar year 2006, sheep were collected from the selected INL allotments before they were moved off site. Three flocks were sampled, including a control flock in Dubois from the Experimental Sheep Station, a flock from a southern INL allotment, and a flock from a northern INL allotment. Two sheep were taken from each flock for tissue analysis. Thyroid, muscle, and liver tissue were collected and analyzed for gamma emitting radionuclides.
Figure 13. Grazing and land ownership on and around the INL.
Levels of 131I are of particular interest in thyroids because of this organ's ability to accumulate iodine. No +I was found in thyroids from any of the animals.
Analysis for 137Cs showed results greater than the 3s analytical uncertainty in one muscle sample collected from a sheep in the Northern allotment. Both concentrations of 137Cs were similar to those found in both onsite and offsite sheep samples during recent years. Data for all sheep samples are listed in Appendix C, Table C-10.
One large game animal (a pronghorn) were sampled during the second quarter of 2006. No human-made gamma-emitting radionuclide was detected in any tissue of the pronghorn. The data for 137Cs and 131I are listed in Appendix C, Table C-11.
Return to Index