Certified Crop Advisor Practice Exam

Which property makes a chemical more likely to persist in the environment?

1. High solubility

2. Low volatility

3. Rapid degradation

4. Strong adsorption to soil

The correct answer is: Low volatility

A chemical that has low volatility is more likely to persist in the environment because it does not easily vaporize and enter the atmosphere. This characteristic means that the compound remains on the ground or in the water rather than dispersing into the air, which can lead to a longer residence time in the environment. Low volatility reduces the likelihood of a chemical being lost to air and potentially becoming less available for biological uptake or degradation. In contrast, high solubility can lead to a chemical being washed away or diluted in water systems, rapid degradation means the chemical breaks down quickly, and strong adsorption to soil may initially keep the chemical in place but can also lead to eventual degradation through microbial action or chemical transformations. Hence, low volatility enhances a chemical's potential for prolonged persistence in the environment.