Civil procedure: civil actions; action for medical monitoring for individuals exposed to a proven toxic substance; provide for. Amends secs. 20126 & 20140 of 1994 PA 451 (MCL 324.20126 & 324.20140) & adds sec. 20136.

HB 4637 would allow individuals exposed to a proven toxic substance to pursue legal claims for medical monitoring costs. It amends Michigan's Natural Resources and Environmental Protection Act (1994 PA 451) by adding Section 20136 to enable these lawsuits, while also modifying existing liability provisions in Sections 20126 and 20140. The bill directly affects people exposed to toxic substances who seek ongoing medical monitoring, though the provided text does not detail specific eligibility criteria or procedural requirements for the new claim. The context lacks the full text of the added Section 20136, so key mechanisms like cost coverage or qualifying substances cannot be described. This is a substantive policy change, not a procedural resolution.