Some residents in Chesapeake, Va., have hired experts to build a case against the city stemming from trihalomethane (THM) contamination of the municipal water supply during the 1990s. Forty-three women have charged that city officials have not been truthful with the information about levels of THM in their region. Among the charges are that city officials concealed test information on THM levels, failed to provide adequate warning of the elevated levels of THM in the water, and failed to disclose to the public the association between THM and miscarriages, stillbirths and birth defects.