…What evidence is missing from the CIR report
The fact that these are extremely widespread and found in up to every second product of everyday life, not just cleaning detergents, paints and insulations but a majority of everything which, at one point during its production, came into contact with water or needed some protection against microbes does contain at least traces.
It’s one of the most efficient and cheapest preservatives for everything and therefore used and produced in insane quantities worldwide and that’s the problem. It’s everywhere whether you want it or not. Obviously, this dramatically increases sensitisation prevalence reaching now, depending on the publication, about 0.1% of the population being allergic to MIT and ~2% to CMIT, respectively.
Furthermore, your report doesn’t mention the ban of MIT/CMIT in leave-on cosmetics in Canada and EU (I didn’t double-check to verify). It also doesn’t mention that since that ban, prevalence of isothiazolinone allergies were declining.
The two links do mention high assimilation of applied product and state a long half-life. That stuff accumulates badly with its t1/2 of about 2 weeks. However, others found different levels of assimilation and excretion times of a few days whilst others failed to measure considerable blood levels… it’s a mess.