What Damage Can Pesticides Do?

Most people use pesticides at some point in their life – whether it is something to kill those persistent weeds, to get rid of slugs, flies, or ants, or even to treat a case of head lice on your child.

But if they’re designed to kill plants and animals, what other damage can they do?

What Are Pesticides Used For?

Pesticides are a group of chemical solutions which include insecticides, fungicides, disinfectants, and herbicides and which are designed to kill, deter or get rid of unwanted pests – whether they be of animal or plant origin.

The pesticide industry is huge – with 140,000 tonnes being used a year and a quarter of all vegetables, fruits, and cereal crops containing residues of two or more pesticides.

But if the chemicals we’re using and consuming so happily are specifically designed to harm life, what damage are they doing to us and the environment?


All insects and plants perform a specific function. By eradicating one group of insects or plants by using a pesticide, the food source, habitat or mating ground of another might be disturbed.

In this way, our biodiversity is gradually diminished through the use of harmful chemicals and species endangered.


Pesticides are also harmful to the wider environment. They can pollute rivers and streams, causing damage to aquatic life and residues can also enter groundwater polluting our source of drinking water.


The adverse health effects of pesticide use for workers farming intensive crops such as cotton have long been established, with links to cancers and nerve damage.

However more evidence is now beginning to emerge that even in domestic settings where stringent regulations control the use of pesticides, they can be damaging our health.

Pesticide-Polluted Air

Studies are now showing that indoor air samples regularly indicate much higher levels of pesticide present than would have been expected. It is not known how pesticides can be polluting our homes but the theory is that it is being trodden in underfoot on shoes or by pets, and may also be settling in dust from the air. Chemicals present in indoor dust samples are being linked with higher incidences of cancer in Western populations.

There is also new research to show that even domestic gardeners who are exposed to pesticides for any considerable time are putting themselves at risk. While pesticides for garden use are considered safe if used properly, Dutch researchers report that long-term exposure could lead to users suffering cognitive problems such as confusion and impaired brain function.

Alternatives To Pesticides

There are many safe, organic and biological alternatives to using chemical pesticides. Although pesticides can give a ‘quick fix’ to crops and gardens, at what cost is it to nature and our health?

Before using a pesticide in the future, consider the following:

  • Use alternative methods of controlling slug damage – there are many types to try.
  • Pull up weeds manually.
  • Use a nit comb and conditioner to get rid of head lice – research shows it can be more effective than using a chemical.
  • Use humane mouse traps and fly paper rather chemical bait or sprays.
  • Stop using disinfectant to wipe down surfaces.
  • Wash fruit and vegetables before eating.
  • Buy organic food from sustainable, fair trade sources.
  • Consider if you really need to spray your garden with weed killer.