HuffPost’s Game Changers series celebrates 100 innovators, visionaries, and leaders in 12 categories who, whether working in the spotlight or under the radar, are changing how we look at the world and the way we live in it. We salute them for their willingness to look at things and take the risk of saying, “I think I have a better way.” Now it’s up to you to pick the Ultimate Green Game Changer. Click through the slideshow below, get the lowdown on why we chose each Game Changer, then VOTE for your favorite! We’ll reveal your picks in October. Changed the game by … walking the Gulf Coast to uncover BP’s cover-up attempts. Ott is an activist and trained marine toxicologist who has for many years worked to expose the public health problems caused by oil spills. This past spring, she took her camera and expertise to the Gulf of Mexico, gathering stories and images of the damage wrought by BP. When the Coast Guard stonewalled would-be observers, when BP destroyed evidence of animal carcasses, when the public health dangers piled up and clean-up workers were told to avoid health precautions, Ott sounded the alarm by going on television and posting her reporting online. How it all started: Ott decided to become an activist after the 1989 Exxon Valdez spill off the coast of Alaska; she was working in the region as a commercial “fisherma’am.” Must-click link: Riki’s blogsRiki is the author of two books, Not One Drop, and Sound Truths and Corporate Myth$. Find out more in our bookstore!