The theory holds that because mesothelioma has no established safe threshold, each exposure above background contributes to the cumulative dose and therefore to causation. Plaintiff experts use it to establish specific causation without quantifying individual exposures.
Defense challenges argue it is not a methodology at all but an assumption that dispenses with dose analysis.
Alternative Names:
Any Exposure Theory, Single Fiber Theory
Why it Matters?
This theory is the central Daubert battleground in asbestos litigation because it would establish causation against any defendant whose product the plaintiff encountered at all. Courts have increasingly excluded it as failing to apply the dose-response principles that underlie toxicology, though acceptance remains inconsistent. Whether the forum admits it effectively determines whether exposure quantification matters in the case.
Frequently Confused with
Related terms
Frequently asked questions
Why do defendants challenge the theory?
Have courts excluded it?
