Question: Is there a study which indicates what levels of arsenic in soil are acceptable/safe to permit human habitation?
Yes indeed there are several! Anaconda Montana, Denver Colorado and Omaha Nebraska are just a few. The one fact to be aware of is that each state has their own criteria for acceptable levels of arsenic in soil. In Anaconda it is 250 PPM, in Denver it is 75 PPM in Omaha it is 70 PPM for children, adults much higher. In New York it is 13 and 16 PPM depending on the land usage. The reason for the disparity is what naturally occurs in each state and what assumptions are used by the calculating government agencies. What seems to be lost is that we are all the same species of humans and what is safe for one region should be the same for another.
For more information and documents covering some of the studies, look through the Document Repository on this site in Arsenic In Soil - Related Documents within the repository section. (Use this link [3]). The Health Consultation report for Omaha prepared by the Agency for Toxic Substances and Disease Registry which is part of the Federal Department of Health and Human Services is one of the documents there (look for Health Consultation - East Omaha, Nebraska).
