In researching a recent court decision in a TCE case (more on this later), we stumbled across this paper [PDF] from the William Mitchell Law Review, Vol 32, Issue 3, 2006. Written as guidance for the Minnesota Supreme Court, it reviews the legal concept of medical monitoring and identifies states where this claim is allowed in absence of physical injury or illness:

In “toxic tort” lawsuits, or claims brought as a result of exposure to hazardous substances, a typical plaintiff “alleges he has developed a disease because of exposure to a toxic substance negligently released by the defendant.” In some cases, however, the plaintiffs “seek to recover the costs of long-term diagnostic testing and medical examinations, which they claim are necessary to detect latent diseases or ailments that might later develop as a result of toxic exposure.” This novel theory of recovery is frequently labeled “medical monitoring.” Plaintiffs bringing claims for medical monitoring “seek post-exposure, pre-symptom recovery for the expense of periodic medical examinations to detect the onset of physical harm.” Plaintiffs who bring actions seeking the establishment of a medical monitoring fund may not suffer any current physical injuries and often do not even exhibit symptoms of disease as a result of their alleged exposure.

States That Allow Medical Monitoring in the Absence of Present Physical Injury

State	Authority
Arizona	Burns v. Jaquays Mining Corp., 752 P.2d 28 (Ariz. Ct. App. 1987)
California	Potter v. Firestone Tire & Rubber Co., 863 P.2d 795 (Cal. 1993)
Colorado	Cook v. Rockwell Int’l Corp., 755 F. Supp. 1468 (D. Colo. 1991)
Connecticut	Martin v. Shell Oil Co., 180 F. Supp. 2d 313 (D. Conn. 2002)
District of Columbia	Friends for All Children, Inc. v. Lockheed Aircraft Corp., 746 F.2d 816 (D.C. Cir. 1984)
Florida	Petito v. A.H. Robins Co., 750 So. 2d 103 (Fla. Dist. Ct. App. 1999)
Guam	Abuan v. Gen. Elec. Co., 3 F.3d 329 (9th Cir. 1992), cert. denied, 510 U.S. 1116 (1994)
Illinois	Lewis v. Lead Indus. Ass’n, 793 N.E.2d 869 (Ill. App. Ct. 2003)
Montana	Lamping v. Am. Home Prods., Inc., No. DV-97-85786 (Mont. 4th Dist. Ct. Feb. 2, 2000)
New Jersey	Ayers v. Twp. of Jackson, 525 A.2d 287 (N.J. 1987)
New York	Patton v. Gen. Signal Corp., 984 F. Supp. 666 (W.D.N.Y. 1997)
Ohio	Day v. NLO, 851 F. Supp. 869 (S.D. Ohio 1994)
Pennsylvania	Redland Soccer Club, Inc. v. Dep’t of the Army, 696 A.2d 137 (Pa. 1997)
Utah	Hansen v. Mountain Fuel Supply, 858 P.2d 970 (Utah 1993)
West Virginia	Bower v. Westinghouse Elec. Corp., 522 S.E.2d

The article goes on to identify states where medical monitoring is not allowed absent a physical injury and also those states where the issue has not yet been decided (or where no test has been articulated).

Read more in Note: A Fifty-State Survey of Medical Monitoring and the Approach the Minnesota Supreme Court Should Take When Confronted with the Issue by D. Scott Aberson [PDF].