In paragraph (226) of the report, the excess risk of mortality from circulatory disease is discussed. “The shape of the dose response is consistent with linear, linear-quadratic and quadratic relationships, although the data for heart disease tend to favour a linear relationship. For heart disease the best estimate of the dose-effect threshold is 0 Gy (i.e., no threshold; 95% CI: <0, 0,5 Gy), whereas it is 0,5 Gy for cerebrovascular disease.” In the executive summary (h), one can read “From current evidence, a judgement can be made of a threshold acute dose of about 0,5 Gy (or 500 mSv) for both cardiovascular disease and cerebrovascular disease”. The situation of knowledge at low dose is poor like for cancer induction, where on the contrary a linear no threshold hypothesis is accepted. A better justification of the difference in the treatment of both situations would be very helpful.