Toxic Materials in a Food Chain

One way that food webs can be disrupted is through the accumulation of toxic materials along food chains. This occurs when organisms at the lower levels of the food web are exposed to harmful substances, such as pesticides.

These toxic materials can then be passed up the food chain as they are consumed by higher-level organisms. This process, known as bioaccumulation, can have devastating effects on the entire ecosystem. It can lead to declines in population and even extinction of certain species.

A good example of this can be seen when pesticides are used in agriculture and get passed along the food chain. In this case, spraying pesticides does not only cause damage to the target pests. It also harms other organisms.

Let’s look at an example:

The pesticides are transferred along the food chain. This is because they cannot be excreted easily by organisms, so they accumulate in their bodies over time.

The animal at the top of the food chain, which is the eagle, will consume the highest concentration of pesticides. This is because it feeds on lower-level organisms that have already accumulated pesticides.

The accumulation of pesticides can make the eagle sick, which can lead to death. Also, the pesticides can affect many other organisms in a food chain, which can lead to the extinction of certain species.


DDT is an insecticide that kills and repels mosquitoes. It was widely used to reduce the spread of malaria, as well as in crop fields. However, DDT is a toxic material that can pass up the food chain from insects to small birds. This can lead to the death of many predatory birds.

As the organisms in a food web are dependent on each other for food, the accumulation of DDT can disrupt an ecosystem. If one of the species in a food web is wiped out, the whole web can be affected. This is why DDT is now banned in many countries.