The United States Geological Survey (USGS) has produced the majority of the scientific work into the problem of coal tar sealant pollution. They generously have worked to educate the public about their research either by webcasts or personal presentations. While this series, which is taken from an August 2010 presentation in Springfield, Missouri, is available in its entirety here (nearly 2 hours in length), it is presented here in briefer, more viewable segments.
Q&A, Where is the EPA? Exposure pathways? What about cancer clusters?
These videos are available by clicking the title of the video. Let me know if this is helpful to you. Future videos will include USGS' approach to scientific studies (why & how they do their work), and some Q&A about the topic.