What toxicity values are used for TCE?
TCE currently has no EPA consensus toxicity value, and multiple estimates of TCE risk may be appropriate. Consult your regional risk assessor to determine whether your region or state has recommended TCE values. The toxicity hierarchy discussed in this FAQ was followed and the resulting toxicity values, except for the RfC, for TCE are from the California Environmental Protection Agency/Office of Environmental Health Hazard Assessment’s toxicity values. After evaluating the Tier 3 sources for noncarcinogenic toxicity values, we have elected not to choose any noncancer toxicity values for TCE. Rather, we will allow cancer-risk considerations to dominate the evaluation of TCE as they are protective of noncancer risks as well. • IRIS presents 2 types of toxicity values for vinyl chloride yet the SL table shows only a single number. Which number was chosen and why? The vinyl chloride calculations were based on the examples given in the Toxicological Review for vinyl chloride, which appears
TCE currently has no EPA consensus toxicity value, and multiple estimates of TCE risk may be appropriate. Consult your regional risk assessor to determine whether your region or state has recommended TCE values. The toxicity hierarchy discussed in this FAQ was followed and the resulting toxicity values, except for the RfC, for TCE are from the California Environmental Protection Agency/Office of Environmental Health Hazard Assessment’s toxicity values: (http://www.oehha.ca.gov/risk/ChemicalDB/index.asp). After evaluating the Tier 3 sources for noncarcinogenic toxicity values, we have elected not to choose any noncancer toxicity values for TCE. Rather, we will allow cancer-risk considerations to dominate the evaluation of TCE as they are protective of noncancer risks as well.
