Under pressure from environmental organizations, the Florida legislature yesterday modified a bill designed to protect dry cleaners from being sued for toxic contamination. The original bill would have prevented people who owned land adjacent to dry cleaners from suing over groundwater contamination; the modified version would retain that provision but grant exceptions to those who sell, transfer, or change the use of their property and can prove economic damage as a result of contamination. For example, a property owner whose well water was contaminated by dry-cleaning chemicals (which can cause liver and kidney problems and are suspected carcinogens) could not seek damages unless she or he also sold the property containing the well. Hundreds of wells around the state are contaminated by dry cleaning chemicals, forcing homeowners to connect to public water sources.