With consumers becoming more and more concerned about greenwashing, the Federal Trade Commission has agreed to review its voluntary environmental marketing guidelines. Today the agency is holding a public forum addressing carbon offsets and renewable energy credits, the first in a series of workshops designed to review the guidelines, which have not been updated since 1998. The launch of the workshops coincides with marketing group EnviroMedia’s introduction of website Greenwashingindex.com, where consumers can rank the greenwashiness of various ads.