The risks of measuring risk -- Session I: Statistical Inference of Risks -- The proper interpretation of significance tests in risk assessment -- Remarks on sequential designs in risk assessment -- Epidemiologic studies of toxic response - significance requirements -- Biological models in epidemiology: radiation carcinogenesis -- Session II: Risks of Prenatal Exposures -- Dose-response relationships for adult and prenatal exposures to methylmercury -- Risk factors for deficits in early cognitive development -- Utilization of critical periods during development to study the effects of low levels of environmental agents -- Epidemiologic studies of environmental exposures in human reproduction -- Session III: Risks of Contaminated Air and Drinking Water -- Health risks of lead as judged from autopsy material -- Use of tests of pulmonary function to measure effect of air pollutants -- Experimental evaluation of air pollutants in humans as a basis for estimating risk -- Problems and possibilities of determining the carcinogenic potency of inhalable fibrous dusts and polycyclic aromatic hydrocarbons -- Session IV: Comparative Risks of Energy Sources -- Some probabilistic aspects of safety assessment -- What is the total risk of energy systems? -- Have the nuclear power risk assessors failed? -- Session V: Genetic and Cancer Hazards -- Cytogenetic bases for risk inference -- Problems and solutions in the estimation of genetic risks from radiation and chemicals -- Evaluation of genetic risks -- Session VI: Extrapolation to Low Doses -- Extrapolation from long term low dose animal studies -I. Review -- Extrapolation from long term low dose animal studies -II. The ED01 study -- The shapes of the radiation dose - mutation response curves in Drosophila: mechanisms and implications -- The cancer risk from low level radiation -- A simple threshold model for the classical bioassay problem -- A biological basis for the linear non-threshold dose - response relationship for low-level carcinogen response -- Participants.