Proposed standards for acute exposure to low enrichment uranium for compliance with 10 CFR 70.61

Title 10, Code of Federal Regulations Part 70, puts forth requirements for licensure of special nuclear material including specific risk criteria for acute intakes based on biological effects. Standards for acute oral and inhalation intakes of soluble low enrichment are proposed for the three levels of biological effects given in the regulations. These levels were developed largely from available human data and have a large measure of conservatism. The proposed threshold for life endangerment was 500 mg for acute inhalation intakes and 2,500 mg for acute ingestion intakes. Acute intakes of 1,400 mg for ingestion and 100 mg for inhalation are proposed as thresholds for irreversible or serious long lasting health effects. For minor transient health effects, the proposed levels are 410 and 30 mg, respectively, for acute ingestion and inhalation intakes. For acute intakes below these levels, no demonstrable toxicological effects are anticipated.