Busby
"Busby's chief notoriety is his modelling work on natural background radiation, which is highly controversial. It's often self-published, and the Journal of Radiological Protection put out a paper (PDF/45KB) debunking his work".
Hmm, this is a completely non-peer reviewed diatribe consisting of ad hominem attacks and gross, unsubstantiated allegations, written by an admitted paid consultant to the nuclear industry. It's not scientific in the last - not one sentence of it.
If that's the best you have to "debunk" Busby's research, his credibility has just ballooned.
BTW, being that you are so "scientific" and "objective", I was shocked, yes, shocked! not to read about Busby's responses to the allegations you have made against him in your "sensationalist" diatribe. For your readers, you can find a brief explanation at http://www.llrc.org/health/subtopic/compendium_refs.htm .