As climate change becomes more topical, you might have heard statements about pesticides harming pollinators.
Pesticides are bad for the environment because they can spread into the surrounding environment and are harmful to other plants as well as pollinators and animals.
However, they can drastically increase crop yields, so there are pros and cons to pesticide use.
Here’s everything you need to know about the environmental impact of pesticides.
1. How Do Pesticides Affect the Environment?
While pesticides are intended to treat one specific crop or target particular pests and diseases, they can easily spread due to leaching, spray drift, or run-off.
This can cause air, soil, and water pollution.
Exposure to pesticides can also be detrimental to other flora and fauna.
For example, when pesticides enter waterways, they can reduce the number of algae and plankton, which can then reduce fish populations as smaller fish are left with limited food.
Some pesticides may also result in cancer or lesions on fish and animals.
Pesticides come with strict instructions in order to limit exposure to non-target crops and wildlife, so following these can reduce the environmental impact.
One of the bigger talking points when it comes to pesticides is their effect on pollinators.
This would also have a knock-on effect on the ecosystem as animals who eat pollinators would have less food, as well as those who eat the fruit of the plants pollinated by bees.
The problem is that many kinds of pesticides are harmful to bees.
One, in particular, are neonicotinoids which can make their way into pollen and nectar.
When bees are exposed to it, they may suffer memory damage, which may make them less effective pollinators and less likely to survive.
It can also negatively impact their reproduction.
It should be noted that pesticides are not solely to blame for declining bee populations, as the changing climate and fewer habitats also play a role.
There are some positives to pesticide use.
Pesticides can increase crop yields by 30%, which can be good for the economy as farmers can sell more products and may also help prevent food shortages and feed the growing population.
Without pesticides, fruit and vegetable production could drop by 78% and 54% respectively, and cereal production could drop by 32%.
Crops grown without the use of synthetic fertilizers may require more land to produce the same yield.
The use of pesticides means that crops are protected from pests, such as insects feeding on the plants and disease.
This can reduce waste as the crop is less likely to be wiped out by disease or degraded by pests.
However, there is still waste associated with pesticide use.
While large farms may have the resources to clean up waste, smaller businesses can struggle to dispose of unused products or treat contaminated soils and rinse water.
For example, a larger farm may have access to an incinerator to discard contaminated soil.
If this waste is not handled appropriately, pollution can spread.
2. Do Pesticides Contribute to Climate Change?
Approximately 17% of greenhouse gas emissions are associated with agriculture.
While pesticides are harmful to animals and pollinators, their contribution to climate change is rarely considered.
However, it requires a lot of energy to manufacture synthetic pesticides.
Most energy use worldwide is still reliant on fossil fuels, so energy-intensive products are not sustainable.
The production of pesticides can emit approximately 6.3 kg of CO2 per kg, while synthetic nitrogen fertilizers can emit 1.3 kg of CO2 per kg.
Research found that greenhouse gas emissions in Austria from 2000 to 2019 associated with cumulative pesticide production totaled 331,279,525 kg CO2e.
The emissions also varied per crop, but this is likely to do with how some crops are more pesticide intensive than others.
This can be influenced by the soil quality, pests in the area, local weather conditions, and socioeconomic factors.
For example, 51% of the total greenhouse gas emissions from apple production were due to the production and application of pesticides, but only 37% for viticulture and 12% for sugar beets.
3. Are Pesticides Used in Organic Farming?
It should be noted that there are several definitions of “organic”: in chemistry, the term organic refers to compounds with carbon-hydrogen bonds or carbon-carbon bonds.
This is why some fertilizers, pesticides or herbicides accepted in organic farming do not fit that definition of organic used by chemists.
Likewise, many synthetic chemicals used in conventional agriculture would be classified as “organic” compounds by a chemist (i.e. contain carbon bonds), but are nevertheless not allowed in organic farming.
Organic can also refer to things that come from living matter.
As for agriculture, it relates to crops grown with organic fertilizers like manure, compost or guano.
You may also see crop rotation or companion planting associated with organic farming.
For the purpose of this article, organic refers to things that come from living matter and produce grown in accordance with organic farming standards.
In order for food to be labeled as organic, it must not have been treated with prohibited substances, such as synthetic pesticides, genetic engineering, ionizing radiation, or sewage sludge.
Moreover, it must contain at least 95% certified organic content – this is pertaining to organic farming practices and living matter.
Contrary to popular belief, organic farming is not actually pesticide-free; but they use fewer and other types (more natural) pesticides.
For example, to be classed as USDA Organic, the crop cannot have been grown with synthetic pesticides, herbicides, and fertilizers, but many natural or non-synthetic pesticides and fertilizers are acceptable.
The land the crops are grown on must not have been treated with any banned substances for at least three years before the harvest.
In 2007, more than 1% of organic food tested by the European Food Safety Authority had non-organic pesticide levels over the legal limit.
Another example is when Consumer Reports purchased 454 kilograms of organic fruit and vegetables from five cities and found traces of synthetic pesticides in 25%.
4. Are There Eco-Friendly Pesticides?
Pesticides allowed in organic farming are generally much less harmful or toxic than synthetic alternatives.
But that doesn’t mean that all of them are completely harmless (some are), which is why they are regulated and still need to be used with caution.
However, in general, natural pesticides seem to be effective with a reduced environmental impact compared to man-made substances.
Almost all pesticides which are allowed in organic farming occur naturally – they’re either derived from plants, animals or found in the earth’s crust.
Some examples are citronella, spearmint oil, quartz sand, iron, potassium or beeswax.
Research found that neem oil, lavender oil, and cottonseed oil were effective at killing or repelling pests, while garlic oil and mint oil were good at repelling pests.