Pesticide pollution


What are pesticides?

According to the European Commission a 'pesticide' is "something that prevents, destroys, or controls a harmful organism ('pest') or disease, or protects plants or plant products during production, storage and transport."
The term includes, amongst others: herbicides, fungicides, insecticides, acaricides, nematicides, molluscicides, growth regulators, repellents, rodenticides and biocides.

But pesticide use causes several problems to the environment and humans. Pesticides are used in public health to kill vectors of disease, such as mosquitoes, and in agriculture to kill pests that damage crops. People are exposed to low levels of pesticides through food and water and are generally not a cause for concern. The people at greatest risk of adverse health effects are those who work directly with pesticides, such as agricultural workers.


History of pesticides

The history of pesticide use can be divided into three time periods:

  • Before 1870, pests were controlled using various natural compounds. The first documented use of pesticides was around 4500 years ago by the Sumerians.
  • Between 1870 and 1945, the adoption of synthetic materials of an inorganic nature emerged. Toward the end of the 19th century, Swedes employed compounds containing copper and sulphur to protect fruit and potatoes from fungal attacks.
  • The third era commenced post-1945, marked by the introduction of synthetic pesticides following the discovery of the effects of chemicals such as Dichlorodiphenyltrichloroethane (DDT), β-Hexachlorocyclohexane (BHC), aldrin, dieldrin, endrin, chlordane, parathion, captan, and 2,4-D.

Subdivision of pesticides

Based on application areas:

  • plant protection products: active ingredients used in agriculture, forestry and horticulture
  • biocides: active ingredients used in non-agriculture sectors.

Based on the target organisms:

  • herbicides: against weeds
  • fungicides: against fungi attack
  • insecticides: against various insects
  • molluscicides: against mollusks
  • nematicides: against roundworms
  • acaricides: against mites
  • rodenticides: against rodents

Herbicides Insecticides Fungicides
Root herbicides Action by ingestion Systemic fungicides
Foliar herbicides Contact action Fungistatic
Action by inhalation Seed tanning products
Systemic insecticides
More info

Advantages to pesticides

    Increased Crop Yields:

    The use of pesticides across various sectors, including agriculture, forestry, public health, and domestic applications, has brought significant benefits. They enhance food grain production through high-yield seed varieties, advanced irrigation techniques, and pest control. Pesticides minimize crop losses, thereby increasing yields and economic margins. Additionally, they contribute to environmentally sustainable practices by producing non-toxic metabolites.

    Cost-Effectiveness:

    Dealing with pests can be costly for farmers. Pesticides can be a cost-effective solution compared to other methods, such as manual labor or biological control, which can require more resources and time.

    Reduced Food Waste:

    Without pesticides, a lot of crops would be lost to pests and diseases. By using pesticides to protect crops, we can reduce the amount of food wasted due to damage, helping to ensure a more stable food supply.

    Public Health:

    Pesticides aren't just for crops; they also help control pests that spread diseases to humans, like mosquitoes carrying malaria or ticks carrying Lyme disease. By controlling these pests, pesticides can help prevent outbreaks and keep people healthier.

    Vector disease control:

    Insecticides play a crucial role in controlling vector-borne diseases like malaria, which cause thousands of deaths daily, particularly in developing countries such as India. Disease control measures are essential not only for public health but also for safeguarding livestock and preventing economic losses.

    Quality of food:

    In developed countries, research suggests that the health benefits of consuming fresh fruits and vegetables outweigh the risks of low pesticide residues. Regular consumption of these foods is linked to reduced risks of cancer, high blood pressure, heart disease, diabetes, and stroke. Research found that apples and blueberries, rich in antioxidants, can protect against cancer and heart disease, with increased consumption attributed to improved weed control through herbicide use.


Issues with pesticide use

Health Issues Environmental Issues
  • Short-term effects of pesticide exposure include:
  • Nausea and vomiting
  • Skin irritation
  • Respiratory irritation
  • Convulsions and potential death in severe cases
  • Long-term effects from prolonged exposure include:
  • Various types of cancer (leukemia, lymphoma, prostate cancer)
  • Respiratory issues
  • Neurodevelopmental problems
  • Hormonal imbalances due to interference with the endocrine system
  • Disruption of prey-predator relationships and ecosystem balance
  • Harm to pollinators, particularly bees, due to pesticides like neonicotinoids
  • Significant decline in bee populations, impacting agriculture and ecosystem health
  • Widespread use of pesticides in regions like South Tyrol, leading to continuous environmental pollution
  • Seasonal decrease of 76% in flying insect biomass over 27 years, impacting flower pollination and ecosystem dynamics
  • Unknown effects on ecosystems due to the spread of pesticides through wind and waterways

Alternatives to pesticides

  • Biological Pest Control: This involves using natural predators, parasites, or pathogens to control pests. Ladybugs, praying mantises, and certain nematodes are examples of beneficial insects that can help keep pest populations in check.
  • Crop Rotation: Rotating crops can disrupt pest life cycles and reduce the need for pesticides. By alternating the types of crops planted in a particular area each season, you can help prevent the buildup of specific pests.
  • Companion Planting: Some plants can naturally repel pests or attract beneficial insects. For example, marigolds emit a scent that deters many pests, while plants like basil and lavender attract bees and other pollinators.
  • Organic Sprays: There are organic sprays made from natural ingredients like neem oil, garlic, or soap that can help control pests without harming beneficial insects or the environment.
  • Physical Barriers: Installing physical barriers like row covers or netting can protect plants from pests without the need for chemical treatments.
  • Trap Cropping: Planting specific crops that pests prefer next to the main crop can lure them away, reducing damage to the primary plants.

Sources


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Background image: https://www.kickingdesigns.com/2013/09/apples-9-20-2013

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