I fear that your coverage of long-term health effects from nuclear testing in Kazakhstan could unjustifiably promote the public’s phobia about nuclear energy and detract from what nuclear power can do for the global climate (see Nature 568, 22–24; 2019).

Since the fall of the Soviet Union in 1991, Kazakhstan’s Semipalatinsk site has been secured and surveyed, and the results published (N. A. Nazarbayev et al. Scientific, Technical and Engineering Work to Ensure the Safety of the Former Semipalatinsk Test Site Vols 1–3; 2017). The nuclear accidents at Chernobyl, Goiânia and Fukushima have indicated that damage to human health from radiation and radioactivity is rare (see go.nature.com/32wxw5b). In my opinion, enough is known today from germline biology to confirm that any risk from historical exposures to radiation is limited.

The blast released by a nuclear weapon is highly destructive over many kilometres. However, radioactivity and low or moderate levels of radiation are much less harmful, as a century of medical use and laboratory tests attest.