title: Replacing the no-effect level (NOEL) with bounded effect levels (OBEL and LEBEL).
abstract: From experiments or epidemiological studies designed to search for a particular toxic effect, it is in general possible to determine an upper bound for that effect. This observed bounded effect level (OBEL) is defined for both positive and negative experiments. It is non-zero even for negative experiments, and it is inversely related to the size of the exposed group. The OBEL can be used to determine the linearly extrapolated bounded effect level (LEBEL) for various effect doses. Contrary to no-observed-effect' levels (NOELs), LEBEL values are designed to protect against type II (false negative) errors. It is proposed that LEBEL values replace NOELs as a tool for decision-making.
mesh_terms: D000818:Animals; D016001:Confidence Intervals; D003627:Data Interpretation, Statistical; D005234:Fatty Liver / Q000139:chemically induced; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects; D008654:Mesothelioma / Q000139:chemically induced; D019055:No-Observed-Adverse-Effect Level; D016273:Occupational Exposure / Q000009:adverse effects; D012142:Respiratory Tract Neoplasms / Q000139:chemically induced; D012997:Solvents / Q000633:toxicity; D018675:Toxicity Tests / Q000379:methods*
chemical_list: D012997:Solvents