You've heard of home pregnancy test kits. Now, a company in Research Triangle Park, N.C., is developing a do-it-yourself kit for detecting contamination in water, air, and soil. EnSys Inc. says its tests will be used to establish on site how far a pollution problem has spread or if a cleanup has been completed. With $4.5 million in venture capital, the company sees a potential market of $750 million.

-- Leslie Brokaw