What is the linear no threshold model?
The linear no-threshold (LNT) model effectively states that there is no safe level of exposure to ionizing radiation, and that cancer risk can be increased at any level of exposure. It was the primary conclusion of the BEIR VII report. Alternative models include a linear model with threshold, a super-linear model, and radiation hormesis. These models were not felt to be supported by the data analyzed for the BEIR VII report. There has been much confusion and controversy about deriving cancer risk based on radiation exposure since the introduction of the LNT model  . In addition, the appropriateness of the LNT model continues to be questioned, while the lifetime attributable cancer risks based on the BEIR VII report are often incorrectly quoted as scientific fact rather than as “subjective confidence intervals” that incorporate opinion in addition to numerical analysis.