Question

Why are nonpersistent pesticides not as environmentally sound as first thought?

Short answer

Non-persistent pesticides were initially thought to be environmentally sound due to their rapid decomposition preventing accumulation in the environment. However, they often break down into harmful by-products and require more frequent application, increasing toxin exposure in the environment. Thus, they are not as environmentally sound as first thought.

Step-by-step solution

Understanding Non-Persistent Pesticides

Non-persistent pesticides are those that break down quickly in the environment, typically within days or weeks. While they were initially thought to be environmentally friendly due to their rapid decomposition, further research has shown this is not entirely the case.

Discussing Disadvantages of Non-Persistent Pesticides

There are a few reasons why non-persistent pesticides are not as environmentally sound as first thought. Although they break down quickly, they often break down into by-products that can be harmful to the environment. Furthermore, due to their short lifespan, non-persistent pesticides may need to be applied more frequently which can lead to higher toxin exposure for non-target organisms.

Conclusion

In essence, non-persistent pesticides were initially thought to be environmentally friendly because they break down quickly and were believed not to accumulate in the environment. However, their metabolites can be harmful and their required frequent use increases the overall toxin exposure in the environment, making them not as environmentally sound as first thought.