Which term describes a chemical that tends to remain in the environment for long periods and decomposes slowly?

• A. Biodegradable
• B. Persistent
• C. Volatile
• D. Reactive

Answer: (B)

The main idea is how long a chemical lasts in the environment. A persistent substance is one that remains for long periods because it decomposes slowly, so it stays around and can spread through ecosystems. This slow breakdown means it can accumulate over time and continue to pose risks to wildlife and humans.

Biodegradable means it can be broken down by living organisms and microbes, so it doesn’t stay around. Volatile describes a substance that readily becomes a gas and moves into the air, not necessarily staying in the environment for a long time. Reactive means it readily participates in chemical reactions, which can either break it down or transform it, so it isn’t inherently long-lasting.

So the term that fits describes a chemical with a long environmental lifetime and slow degradation: persistent.