Which list contains pure or commercial grade substances that are toxic plus other hazardous characteristics?

• A. P List
• B. K List
• C. U List
• D. F List

Answer: (C)

The concept being tested is how hazardous wastes are categorized when they come from commercial chemical products. Both the P and U lists identify discarded commercial chemical products, including pure or commercial-grade substances. The P list is reserved for acutely toxic materials, highlighting immediate danger. The U list, on the other hand, covers toxic substances that also carry other hazardous characteristics—such as ignitability, corrosivity, or reactivity. Since the question specifies a toxic substance with additional hazards, this category is the best fit. The F list and K list describe waste streams from specific sources or processes rather than pure product chemicals, so they don’t match this scenario.