There is evidence from different sources that risk of mesothelioma is decided by the age of 30 in highly exposed workers. Exposure after that age doesn’t make a measurable difference to risk. Further exposure is harmless as far as mesothelioma is concerned.
Popular orthodoxy would say this conclusion couldn’t be true but would proponents of such orthodoxy have measurable proof? La Vecchia and Boffetta didn’t find any.
The result could become influential in the debate following the recent triggers ligation (Durham v BAI (run-off) etc). In this, it was found that injury-in-fact occurred at exactly 5 years prior to diagnosis. The temptation is to say, if already injured then further exposure is harmless. If so then causation policies in the preceding 5 years would not be triggered. If La Vecchia and Boffetta are right the harmless period could be a lot longer.