stochastic effect

Consequence for which the probability of occurrence depends on the absorbed dose; hereditary effects and cancer induced by radiation are considered to be stochastic effects. The term 'stochastic' indicates that the occurrence of effects so named would be random. This means that, even for an individual, there is no threshold of dose below which there is absolutely no probability of an effect occurring, and the chance of experiencing the effect increases with increasing dose.
Source:
PAC, 2001, 73, 993 (Risk assessment for occupational exposure to chemicals. A review of current methodology (IUPAC Technical Report)) on page 1023