An organic compound from components of pipe, coatings, and joint adhesives would most likely include...

• A. polychlorinated biphenyls
• B. acylamide
• C. polynuclear aromatic hydrocarbons
• D. polyvinyl chloride

Answer: (C)

Polynuclear aromatic hydrocarbons are strongly linked to coal tar and bitumen-derived materials used in pipe coatings and joint adhesives. These coatings and sealants often contain coal tar pitch, which is rich in PAHs, and these compounds can migrate into water or become associated with sediment, making them a common organic contaminant of concern from such sources. PAHs are persistent and nonpolar, so they tend to resist simple treatment and require targeted removal like activated carbon or specialized filtration.

In contrast, polychlorinated biphenyls are legacy contaminants more tied to old electrical equipment and certain older sealants, not typical of standard pipe coatings today. Acrylamide relates to polymer production and processing contaminants rather than coatings for pipes. Polyvinyl chloride is the polymer used to make pipes themselves, not an additive from coatings or joint adhesives.