MDARD Michigan Core Pesticide Applicator Practice Exam

Which environmental condition can slow down the breakdown of pesticides?

1. High humidity

2. Cool, dry conditions

3. Wet soils

4. High temperatures

The correct answer is: Cool, dry conditions

The breakdown of pesticides is influenced by several environmental conditions, and cool, dry conditions can significantly slow this process. In cooler temperatures, microbial activity, which is essential for the degradation of many pesticides, tends to be lower. This reduced microbial activity means that pests, fungi, and bacteria that typically help break down and decompose pesticides are less active, leading to a longer retention time in the environment. Additionally, dry conditions can reduce the moisture available for these microbes, further hindering their effectiveness in breaking down pesticide compounds. Conversely, high humidity, wet soils, and high temperatures generally promote the breakdown of pesticides. High humidity and wet soils create a more favorable environment for microbial activity, while warm temperatures can accelerate chemical reactions, including those involved in the degradation of pesticides. Thus, cool, dry conditions distinctly slow down the breakdown process, supporting the idea that this environmental state is influential in prolonging the presence of pesticides in the environment.