Sakharov drew attention to the radioactive contamination of the biosphere, which emerges under nuclear tests in the atmosphere and under water, when the products of the explosions are strewn over great distances.
Even insignificant doses of additional radiation exposure which does not kill people provokes so-called non-threshold biological effects — a general increase in morbidity and mortality which continues from generation to generation.
“I calculated that every megaton of test explosions in the atmosphere costs the lives of 10,000 people”.
Feeling himself responsible for the radioactive contamination of the planet, he set himself the goal to achieve an end to the dangerous tests.
When in July 1961, he tried to convince Khrushchev to refrain from the continuation of nuclear tests, Khrushchev was outraged.