Study with workers in nuclear industry suggests increased risk of cancer deaths | Hacker News Reader

Study with workers in nuclear industry suggests increased risk of cancer deaths

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16 pointsbelter3 comments

There is the actual study: https://www.bmj.com/content/382/bmj-2022-074520

The analysis doesn't inspire a lot of confidence.

> We interpret the P value as a continuous measure rather than limiting interpretation to dichotomisation of the P value at a threshold for declaring significance (such as 0.05)

That seems weird to me.

The figure https://www.bmj.com/content/bmj/382/bmj-2022-074520/F1.large... shows a lot of their datapoints confidence intervals crossing 1.0

In addition, they are using 90% confidence intervals instead of 95% saying that this is what is often used in these types of studies. Interestingly, in their discussion, the other studies that have 95% confidence intervals seem to cross 0, quite a lot.

In addition, in their discussion, they characterize other studies as showing difference when the confidence interval includes 0:

>Analyses of mortality among French nuclear workers showed a positive association between estimated colon dose and solid cancer mortality (excess relative rate 0.69 (95% confidence interval −0.28 to 1.77) per Gy)58; we note that INWORKS includes a sizable fraction of this cohort. Analyses of mortality among US nuclear workers showed a positive association between cumulative dose and solid cancer mortality (excess relative rate 0.19 (95% confidence interval −0.10 to 0.52) per Gy), which was of larger magnitude among workers first hired after 1960

All this together makes me suspicious

The INWORKS study and reports are among the best there are. What's new about this report is that error bars for low doses are much smaller, presumably due to more stringent dose quality requirements and better dosimeters, which became available only well after may nuclear processing plants came online. For high cumulative dose, there are fewer workers exposed, so error bars are of necessity large. This paper reports excess relative cancer death RATES rather than excess relative death RISKS (of course very similar) Error bars crossing reference lines are not uncommon at low doses in this biz, and have been attributed to "radiation hormesis", a BENEFICIAL or protective effect of ionizing radiation exposure at "low doses", currently believed to be somewhat more than background radiation exposures. Such hormesis naturally implies serious corrections to the "linear, no threshold" picture almost universally used in radiation dose/response.

The figure at https://www.semanticscholar.org/paper/Radiobiology-and-Radia... shows hormetic response (ERR<0).

So the new results make it more difficult to defend radiation hormesis if the ERR vs. dose is STEEPER at low doses than at larger doses.

Many many years ago when it was the UK/GB Sizewell B reactor public enquiry it seemed to be the case that nuclear industry workers basically had a lower risk of death from all causes ... except for crossing the road!

Which might not be in conflict with this study, if nuke workers are (say) more careful than the average Jo/Joe and that more than makes up for the above small increase.

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