https://store.astm.org/d2415-98r03.html
D2415 Standard Test Method for Ash in Coal Tar and Pitch
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https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/coal-tar
Coal Tar and Coal-Tar Pitch - Cancer-Causing Substances - NCI
Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include...
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