What Are Pesticides?

Jessica Clifton

by Jessica Clifton

22nd April 2020

Even as human society progresses, people’s basic needs still include food, warmth, and health. In many countries, however, there are still factors which hinder us from attaining these crucial goals. How do pesticides come into this? And what are pesticides?

Loss of agricultural yield due to natural calamities or disease has always been an issue, more so if paired with other variables like depleted soils and harmful pests. That is why it is important to eliminate or at least lessen their destructive effects by means of methods like the application of pesticides.

The basics: what pesticides are

Pesticides are any chemical substances, mixed or not, that are used to kill, reduce or control pests for various purposes. Pests are any destructive biological components such as animals, plants, microorganisms, fungi, and the like that damage other living organisms. The latter is specifically being protected.

There are different kinds of common pesticides:

  • Herbicides – toxic to particular plant pests such as weeds
  • Insecticides – toxic to some targeted insects, such as but not limited to mosquitoes, flies, and roaches
  • Fungicides – toxic to several fungi and their spores such mildew and blights, among many

Other kinds of common pesticides are rodenticides (against rodents along with other small mammals), bactericides (for bacteria, and certain parasites), molluscicides (for snails and other molluscs), and larvicides (specific insect larvae).

The wide technical classifications of pesticides can be grouped according to their specific or general functions, chemical families, and/or formulating aspects.

What chemicals are in pesticides?

You can control pests through the use of pesticides because they contain chemicals which are toxic to the pest. The combination of substances that form active toxic compounds aims as much as possible to affect only the specific pests being targeted without damaging other organisms.

These are some chemicals commonly used as active ingredients in pesticides:

Chemical manufacturers can supply pesticides using a variety of different chemicals in a number of combinations to most effectively target the particular pest in question.

How pesticides are used in agriculture

Continuous food production is obviously critical worldwide. Maximising harvests means minimising pests which can severely affect the amount and quality of yield. This is why using pesticides is an essential tool in agriculture.

Farmers spraying pesticides on a field

Harmful organisms affecting certain plants or animals that are being cultivated or grown have to be managed for better distinct functions. For example, weeds are eradicated to regulate the growth of plants and help livestock thrive on quality food. Fumigants protect the plant products to be harvested while defoliants destroy undesirable plants or plant parts. These two often work together in multifunctional herbicides. Some pesticides may also be non-selective with a wider target scope, for example, they might be able to kill both molluscs and larvae.

When did farmers start using pesticides?

Around 10,000 years ago, the agricultural era flourished, especially on fertile riverbank settlements. As more harvests were demanded due to a growing population, people tried producing more from farming. However, one of the persistent problems faced by farmers was the proliferation of various pests.

These pests caused diseases, competed for nutrients, and even directly damaged the crops and other major agricultural products before or after their yield. This loss of yield constantly posed severe risks such as famine, so people began to create efficient ways of eradicating pests using pesticides. Ancient pesticides were first recorded around 4,500 years ago in Sumer, now southern Iraq.

Agricultural science and pesticides gradually grew more advanced. Nowadays pesticides are incorporated into modern farming systems along with fertilizers and other tools to ensure farmers maximise yield quantity and quality.

Pesticides in food

Despite all the benefits of using pesticides, there are also clear risks. The main risk is that they may leave traces of residue on food products such as crops. This happens when pesticides build up on the surface of the foodstuff or even underneath the surface as they seep through layers of biomaterial such as soil.

Pesticide residue and associated toxicity can be detected in food. Appropriate legal and scientific regulations keep these levels in check. Since conventional farming normally incorporates the use of pesticides, health concerns have understandably become a default controversial topic among consumers.

Wash fresh fruit and vegetables to get rid of pesticides from food

Washing fresh fruit and vegetables helps get rid of pesticides from food

What health problems do pesticides cause?

The presence of pesticide residue in food and even the environment is continually being studied by research institutions. From their findings, there are already established results about the effects of pesticides to non-targeted subjects like human beings.

Toxicity effects of pesticide residue vary from one demographic to another, depending on the surrounding factors including age group, amount traced, frequency of exposure, and many others.

Pesticides have been known to cause health problems

Pesticides have been known to cause health problems

Health problems caused by pesticide exposure can be acute (short-term) and chronic (long-term). Some common health effects and problems caused by pesticides include:

  • Respiratory tract irritation
  • Sore throat 
  • Dry cough
  • Allergies
  • Eye and skin irritation
  • Headaches
  • Unusual fatigue

In extremely rare cases, sudden death by poisoning or progressive health complications resulting in death has also occurred.

These potential health problems do not necessarily occur in everyone, as multiple variables are to be considered when dealing with exposure to the chemicals found in pesticides. These also do not include particular illnesses such as cancer, diabetes, and so on because the links are too complex for the pesticides to be singled out.

It is also worth noting though that certain lifestyles and pre-existing health conditions may further exacerbate the harmful health effects of exposure to pesticides.

Nevertheless, using pesticides has its pros and cons. Research into pesticides and the use of pesticides is ongoing, and advancements will hopefully mean that any disadvantages are eradicated or further minimised over time.


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