ToxicRisk.com have produced Google Maps for all of the US states based on the EPA Toxic Release Inventory (TRI) data released on March 19th.
To start a search click on a state and you will be taken to that state's Google Map. It is then possible to search by zip code, state, city or place. When you zoom in on an area the map markers become interactive. When you then click on a marker an information window opens with a link to a summary of the toxic risk of that location.
It is also possible to view the data on Google Earth.