Desert Tortoises Exposed to and Affected by High Arsenic Levels

Desert tortoises spend much of their lives in contact with dust, soil and sediments, including potentially toxic elements. A study by USGS scientists on soil, stream sediment and plant samples in the Mojave and Colorado deserts, inhabited by tortoises, revealed abnormal concentrations of arsenic due to nearby mining of arsenic-rich ores. Scientists also found that both shell and respiratory diseases in desert tortoises are linked to arsenic exposure and that the outer layer of a tortoise's shell provides a chronological timeline of elements in their environment. USGS scientists are continuing research in this area by studying inhalation as a pathway for arsenic exposure and assessing which particles are most likely to be airborne. For more information, visit http://www.werc.usgs.gov/pubbriefs/berrypbjan2007b.html or contact Kristin Berry at (951) 697-5361 or kristin_berry@usgs.gov , Maurice Chaffee at (303) 236-1855 or mchaffee@usgs.gov , or Andrea Foster at (650) 329-5437 or afoster@usgs.gov .