In Amchem Products, Inc. v. Windsor (1997) 521 U.S. 591, 138 L. Ed. 2d 689, 117 S. Ct. 2231, the court considered the "legitimacy under Rule 23 of the Federal Rules of Civil Procedure of a class-action certification sought to achieve global settlement of current and future asbestos-related claims. The class proposed for certification potentially encompassed hundreds of thousands, perhaps millions, of individuals tied together by this commonality: each was, or some day may be, adversely affected by past exposure to asbestos products manufactured by one or more of 20 companies." (Id., at p. 597, 117 S. Ct. at p. 2337.) The court concluded that class certification was not proper under the requirement of rule 23(b)(3) that common questions predominate, noting that proposed class members were exposed to different products for different amounts of time, in different ways, and over different periods. The high court also opined that the "exposure-only" plaintiffs shared "'. . . little in common, either with each other or with the presently injured class members. It is unclear whether they will contract asbestos-related disease and, if so, what disease each will suffer. They will also incur different medical expenses because their monitoring and treatment will depend on singular circumstances and individual medical histories.'" (Amchem Products, Inc., supra, at p. 624, italics added.)