Managers of “green” mutual investment funds seek to invest their clients’ money in socially responsible and environmentally friendly companies. But those managers, and individual investors, are often hampered by a lack of information about a company’s effect on the environment. While an index such as the Environmental Protection Agency’s Toxics Release Inventory contains a lot of information about individual companies’ releases of toxic chemicals into the environment, it is difficult, if not impossible, for an investor to gauge how such chemical releases affect human health. That’s why Dinah Koehler, a doctoral student at the Harvard School of Public Health, is developing corporate performance measures that will include both the economic activity of a company and its environmental record. Concerned investors will be able to use her measures to consider the environmental performances of companies when creating investment strategies. The measures she is developing will form her thesis. “The point of my thesis is to give people some kind of toxicity measure that would inform them about the public health risks associated with toxic chemical releases,” Koehler said.