Associate Certified Entomologist (ACE) Practice Exam

What is a common characteristic of chlorinated hydrocarbons?

1. They rapidly degrade in the environment

2. They are broad-spectrum insecticides

3. They are highly selective for pests

4. They are biodegradable

The correct answer is: They are broad-spectrum insecticides

Chlorinated hydrocarbons are indeed known for being broad-spectrum insecticides. This means they are effective against a wide range of insect pests, making them versatile options for pest control. Their mode of action typically involves disrupting the nervous system of insects, which can lead to high mortality rates among various pest populations. This characteristic has historically made them popular in agriculture and public health for controlling a variety of insect species. The other choices reflect misunderstandings of chlorinated hydrocarbons. They do not rapidly degrade in the environment; in fact, they tend to persist for extended periods due to their chemical stability. They are not known for being highly selective either, as their broad-spectrum nature means they can also harm beneficial insects. Lastly, chlorinated hydrocarbons are generally not biodegradable, which raises concerns regarding environmental accumulation and potential toxicity to wildlife and humans.