Can Organic Pesticide Be Harmful?

Today, many gardeners use pesticides to get rid of annoying little critters that eat away at flowers and vegetables. Since synthetic pesticides have a bad reputation, many have switched to organic, but can organic pesticides be just as harmful? 

Organic pesticides can be harmful in certain dosages. However, if you follow the instructions properly and use them only when needed, you will be safe. Take preventative measures to reduce the amount of chemicals you use in your garden, and consider using homemade recipes or biopesticides.

Working with potentially toxic chemicals can be nerve-wracking, especially if it is in your garden. This article will summarize what we know about the harmful effects of organic pesticides and offer ways to reduce the health risks associated with pesticide use. Let’s dive into it!

What Are Pesticides?

Before we get into the main topic, let’s take a moment to review what pesticides are exactly. 

Pesticides are any substance (spray, powder, liquid, etc.) used to kill or prevent further infestations from plants or animals. In other words, pesticides repel pests. There are a few different kinds of pesticides, including herbicides that kill/repel any sort of plants or weeds, insecticides used for insects, fungicides used for fungi, molds, and mildew, and disinfectants that prevent bacteria growth. 

Pesticides usually contain several different ingredients that interact with each other. Many include chemicals and food compounds such as herbs, spices and oils, and other natural materials, including beeswax. 

Are Regular Pesticides Dangerous?

More gardeners are turning to organic pesticides because of the real dangers of regular pesticides. Pesticides are acutely and chronically toxic. Acute toxicity means that pesticides have short term health effects such as eye, skin, and throat irritation and can cause nausea, diarrhea, and vomiting. Other serious acute health effects include seizures, loss of consciousness, or even death (depending on the dosage). 

Not only can there be serious short term effects, but pesticides can also cause several chronic conditions. Exposure to pesticides over a long period can increase the chances of getting asthma, anxiety, depression, Parkinson’s disease, ADHD, and even cancer (leukemia and non-Hodgkin’s lymphoma). 

What Are Organic Pesticides?

Now that we have covered what pesticides are and the possible dangers, it may be more clear why people tend to lean towards organic pesticides. 

Many people believe that organic products do not have chemicals in them, which is not true. Organic pesticides have natural ingredients, but they still have chemicals in them. The chemicals are just from botanical and mineral sources that are not man-made or engineered in any way. Chemicals from botanical and mineral sources tend to break down faster than non-organic products, so they appear to be safer. 

Common ingredients that are in organic pesticides include soap, hydrogen peroxide, and lime sulfur. Something to keep in mind is that even though most organic pesticides are organically derived, there are still some synthetic ingredients in them that are USDA approved. On the other hand, some organic materials are not approved, such as arsenic and strychnine.

Produce is labeled organic if the equipment treating them has not used synthetic pesticides within the past three years. Furthermore, the soil has to have been clean of man-made chemicals to earn the title of organic. 

What Are the Different Types of Organic Pesticides?

There are a few types of organic pesticides. Let’s look at a few. 

Store-Bought Organic Pesticides 

  • Microbial – Microbial pesticides have ingredients that come from fungi, algae, and bacteria. The way microbial pesticides work is by preventing reproduction or introducing a virus into the environment. 
  • Biochemical – This type of pesticide uses naturally occurring pheromones to affect the insect population and stop reproduction. 
  • Mineral – Common mineral ingredients include sulfur and lime-sulfur. Gardeners normally use mineral pesticides to control insects. 
  • Botanical – Botanical pesticides use natural ingredients that come from plants. These ingredients can include Neem, Sabadilla, and Pyrethrins. 

DIY Organic Pesticides

Even though there is a big market for store-bought organic pesticides, there are also many kinds of homemade recipes. Let’s take a look. 

Insects (Natural Predators)- Even though this may seem counterintuitive, some gardeners introduce new insects in their garden to help regulate unfavorable pest numbers such as bees and ladybugs

Garlic – Not only can garlic help your garden be more vibrant and colorful, but it will also deter some types of beetles and larvae. 

organic pesticide
garlic organic pesticide

Vegetable oil – Many people use vegetable oil and mix it with organic dish soap to help deter smaller insects. 

Vinegar – vinegar has many uses, one of which is pesticide. Here are some recipes for a homemade 100% organic pesticide.

Many Effects of Organic Pesticides Are Still Unknown

Over the years, synthetic pesticides have gotten a lot of attention. Pesticides have gotten a bad reputation within the past decade, and research on pesticides has started to grow. As the research results went public, many users started to switch over to organic pesticides, with the belief that natural is better than man-made. 

However, there has not been extensive research on organic pesticides for a few reasons. First of all, the companies that manufacture the products do not wish to conduct research that will show the negative health effects of pesticides. 

Secondly, the farmers who use organic pesticides do not wish to receive backlash over their products, which would decrease their sales. To make money, they have to use pesticides. Since many consumers were unhappy with synthetic pesticides, a lot of farmers switched to natural. 

Lastly, there has been a widespread belief, which we will also cover later, that natural pesticides have to be better than regular pesticides since they are not man-made. Due to these reasons, only recently have researchers started to question the safety of natural chemicals used in pesticides. Let’s take a look at some of the findings. 

Organic Pesticides Are Not Necessarily Safer Than Synthetic Pesticides

A study by Christine Bahlai and colleagues studied the environmental effects of organic pesticides compared to synthetic pesticides. The results showed that organic pesticides still had harmful effects on the environment, some even more so than synthetic pesticides. 

The authors of the study took these findings and concluded that just because a product has natural ingredients does not mean that it is necessarily safer. They say that one should be cautious when buying natural pesticides since the effects could be the same. 

Lastly, the authors mention that researchers should conduct more tests comparing organic and synthetic pesticides to raise awareness and challenge public opinion that anything organic is automatically safer than synthetic. 

A great read is “A Natural Mistake” by James T. MacGregor. The book explains why the belief that organic products are inherently safer than those produced using synthetic chemicals is erroneous. It shows how this mistake has misguided consumers, legislators, and government regulators, and has led to often-unrecognized serious health issues.

Organic Pesticides Can Have a Broad Range of Toxicity Levels

Chris Enroth, a horticulture educator at the University of Illinois, explains that while some organic pesticides are indeed safer than synthetic pesticides, they can still be toxic depending on the type. There is a range of different organic pesticides, and each contains different chemicals. As mentioned before, just because chemicals are organic does not make them harmless. Some organic chemicals may be even more toxic than synthetic chemicals. 

A student at Berkeley mentioned that once researchers started to dive into natural pesticides’ makeup, they found that about half contain carcinogenic materials. This startling news is why Chris Enroth mentions that pesticides, even organic pesticides, are the last resort in his garden. When you use them, he advises to keep them out of reach of children, read the instructions, and not be generous in the application. 

Some Organic Pesticides Require a Larger Dose To Be Effective

The thing about synthetic pesticides is that scientists engineer them to be the least damaging as possible. Scientists do what they can to make the synthetic chemicals effective with as little application as possible. 

For instance, one study compared the applications and environmental effects of natural vs. man-made pesticide chemicals. Researchers focused on rotenone and pyrethrin, which are two common natural chemicals used in products. The study compared those to imidan, a synthetic chemical. 

Researchers found that to be effective, they needed to apply the rotenone and pyrethrin five more times than imidan, the man-made pesticide. These results raise further questions and implications. Even though the natural chemicals may have been safer to begin with, they usually require a larger dosage than synthetic. 

A Berkeley student analyzing this study mentions that the organic pesticides ended up being more damaging to the environment than synthetic since it required a larger application. 

Biopesticides Are Safer Than Most Synthetic Pesticides

Even though you may be discouraged after reading about what studies have to say regarding organic chemicals, there is some good news still. The University of Warwick, which has an established research department, discusses the health effects of biopesticides

Biopesticides are a type of organic pesticide and are natural materials derived from minerals, plants, animals, and bacteria. The chemicals work well to reduce or eliminate pests and diseases in your garden. Research has shown that biopesticides produce a very small amount of toxic material if any. This organic pesticide is safe for humans and does not pose any health risks due to its very low toxicity level. 

However, there are a few cons when using this kind of organic pesticide. The user must be very knowledgeable about the product and application to use it effectively. Secondly, this pesticide will take a bit longer than other man-made chemicals to be effective. Lastly, they may not be effective in harsh environments. Nonetheless, if you maintain a healthy garden, you should not find any problems with it. 

How To Manage the Use of Organic Pesticides in Your Garden

Even though organic pesticides have risks, there are ways to lower the negative effect that pesticides have on the environment around you (including yourself!). 

Monitor Your Garden Closely To Reduce the Need for Pesticides

One of the first ways to manage pesticide use is to prevent it in the first place. A garden with good soil, natural predators, healthy growing conditions, and various plants will not need regular pesticide intervention. If you work hard at obtaining a healthy environment for your plants, you should not be using pesticides often. 

Consider Using Homemade Organic Pesticides

Even though there are hundreds of store-bought, organic pesticides you can buy, there are also a few home remedies that will do the trick. One of the biggest positives about using homemade pesticides is that you will know all of the ingredients. There will not be any unknowns about what you are spraying onto your garden.

As mentioned before, organic pesticides can still contain synthetic materials. So if you want to go as natural as possible, I recommend using a DIY pesticide recipe (we will review a few of these recipes later). 

Use Pesticides Only When You Need To

Another easy way to manage the use of pesticides in your garden is to know when you need them! Using pesticides only when you need to will reduce the harmful effects of the chemicals. 

Paul James, a master gardener, explains that pesticides not only kill the insects that are harming your plants but it kills every insect near the flower, even the insects that are good for your garden. That is why he advises assessing the damage of the pests first. 

Some damage that pests inflict on your plants may look unpleasant, but do not harm the plant itself. If the pests are not actually damaging your plant, Paul advises staying away from pesticides as it could cause further damage. 

Paul further explains that when some plants are chewed by insects, they release a certain chemical into the air. This chemical then alerts insects around the plant, such as bees, that predatory insects are nearby. The bees will then come in and kill the predators. So if your plant only has a little bit of damage, leaving it may be a better solution than buying pesticides. 

The master gardener further explains that if you see fungi growing on your flowers, do not run to the store to buy fungicide. Fungicide is just a preventative chemical. Instead, try cutting some of the leaves off to prevent the spread of the disease. If you take this approach on many issues in your garden, pesticides’ harmful effects will drastically decrease since you are using them less. 

How Can You Reduce the Harm of Pesticides?

Even if you go through all of the steps and work hard to make your garden a healthy environment, you will probably need to use pesticides at some point to keep your garden thriving. When doing so, there are a few things you can do to minimize the risk of pesticides. Let’s take a look at a few. 

Avoid High Exposure 

Under normal circumstances, pesticides do not pose great harm to humans since the required dosage for a garden is small enough to prevent acute health effects. Pesticides become very dangerous when the dosage increases. 

To avoid harm, make sure to read the instructions carefully. Use the exact amount that the bottle says, and no more. If you use more than needed over a long period, you will most likely experience acute and chronic health issues. Consider talking to a fellow gardener who has used the same chemical as you to take extra caution. 

Keep Pesticides Out of Reach of Children

One of the most important things to remember when using pesticides is to store them in a place inaccessible to children. If children get their hands on pesticides, synthetic or organic, the chemicals could cause serious harm or even death. 

Let Others Know When You Are Applying It

A good practice to have when applying pesticides is to make sure the garden is clear and empty before applying the chemicals. Ensure there are no pets or kids in the area, and let your housemates or family members know to stay out of the garden during the process. 

Furthermore, make sure to caution everyone in your home or garden about what chemicals you are using to avoid any surprise allergic reactions. 

Apply the Chemical Properly

As previously mentioned, pesticides become dangerous over time with continued application and higher dosages. A way to reduce the number of chemicals you are applying to your garden is to use them correctly the first time! Applying pesticides at the optimum time will increase their ability to get rid of unruly pests. 

Apply the pesticides on a cloudy day during moderate temperature. Check the weather network to make sure it won’t rain. Additionally, do not apply if it is windy. If you apply pesticides right before it rains, the chemicals will drain down into the soil and potentially contaminate bodies of water nearby. Furthermore, applying the chemicals on a windy day will spread the toxins to other areas. 

Additionally, if you are using pesticides for insects, you will have to know what stage to apply the pesticides at. To further elaborate, insects have different stages of development. Certain pesticides attack insects at specific stages of their development. To ensure proper use, make sure to research the pesticide brand you are using and know how to identify what stage the pests are at. 

Wear Personal Protective Equipment

Before you start the application process, make sure you are wearing the proper personal protective equipment. For every pesticide application, the basics include pants, a long-sleeve shirt, garden gloves, and closed-toe shoes. Furthermore, check if the bottle says to wear anything specific since some chemicals are harsher than others. Extra personal protective gear could include face masks and eyewear. 

Use the Correct Product

Since there are so many products on the market, it will take some time to know what pesticide will be the best for your garden. The first step is to identify the problem. Then you should know who or what is damaging your garden. Is it a fungus? Is it pests? Whether it is a disease or a small insect will determine the type of chemical you need to buy.

When you know who or what the culprit is, do some research to determine what products are best for your problem. Since Google may provide some misleading information, the best way to find out is to ask an expert. Visit your local greenhouse, call up a fellow gardener or even email an expert on pesticides. There are many different resources available. 

Reviewing the many safety precautions of pesticides may be overwhelming if it is your first experience with the chemicals. Refer to the youtube video below for a brief overview of how to stay safe when using pesticides:

If you have a big garden and will be using pesticides at least once a year, I would recommend buying The Safe and Effective Use of Pesticides. As the article has covered, effectively using pesticides is the first step to lower the risk of adverse health effects. This book will give you the knowledge you need to keep your home and garden safe! 

What Are the Safest Organic Pesticides for Your Garden?

After reading the wide range of possible harmful effects that organic pesticides can have on your body, you may be a little anxious about using pesticides in your garden. Fortunately, you can use a few options on garden pests that will not be as harmful. The following list will include both DIY recipes and common, store-bought organic pesticides. 

Before we get started, it is worth noting that before you use any of these remedies on your garden, make sure to test them in a small section on one plant first. One recipe may not work for the specific pest you have, so you may need to try out a few before finding the correct solution. 

Lastly, whenever you are mixing your own natural pesticide, ensure that you do not use bleach. The bleach may burn the flowers or produce on a hot sunny day. 

More about the negative effects of bleach in this article.

Vegetable Oil Recipe

For this recipe, mix one tablespoon of vegetable oil, two tablespoons of baking soda, one liter of water, and one teaspoon of murphy oil or organic dish soap. Combine all of these ingredients into a spray bottle and apply to the affected plant. 

Garlic Recipe

For this recipe, combine one garlic head, two cups of water, one tablespoon of dish soap, and two tablespoons of vegetable oil or mineral oil. You will have to puree the garlic with the water and oil the night before and let it sit for twelve hours. Then you will strain the puree. Put the strained mixture into a spray bottle along with the soap, and it’s ready to use!

Hot Pepper Recipe

Take half a cup of chopped hot peppers and two cups of water and throw it in a blender. For this recipe, hotter pepper will work better. Let the mixture sit overnight. In the morning, strain the mixture and put the liquid into a spray bottle. Add two tablespoons of dish soap, and it is ready to go!

Attract Helpful Insects by Planting Specific Plants

You can also add certain species of plants to your garden that will attract helpful insects. There are many insects that prey on annoying little pests that run ramped in your garden. If you go with this option, it will require quite a bit of planning and work, but once you set your mini insectary up, the ecosystem will run itself, and you won’t have to worry about using extra, possibly harmful pesticides. 

If you decide to set up an insectary, make sure to designate a small plot of land in your garden that is big enough to hold up to seven plants. Below I will list some of the popular plants that can attract beneficial predators. 

  • Amaranthus – Ground beetles 
  • Alyssum – Hoverflies, tachinid flies, and lacewings
  • Cosmos bipinnatus – Hoverflies, lacewings, and parasitic wasps
  • Lupin – Aphidius, aphidoletes, and hoverflies
  • Sunflowers – Pirate bugs, aphodius, and parasitic wasps
  • Yarrow – Hoverflies, parasitic wasps, and ladybugs
  • Shasta daisy – Pirate bugs, beneficial mites
  • Digitalis – Dicyphus
  • Shasta daisy – Pirate bugs, beneficial mites 

Bacillus Thuringiensis

You can find this pesticide in stores. Bacillus Thuringiensis is a stomach toxin that will prevent pests from eating, which will cause them to starve. The pesticide generally comes in a powdered form and is sprinkled over the affected areas. This chemical is safe for humans. 

Horticulture Oil

This type of pesticide is highly refined petroleum oil. All you have to do is mix it with water and spray the affected areas. The oil coats the insects and either kills them or disrupts their eating patterns. Many gardeners prefer this chemical since it does not leave toxic residue and has a very low toxicity level, so it is safe for humans to use. 


There is not much research on organic pesticides, so many of their effects on health remain unknown. However, the few studies that researchers conducted show that some organic pesticides can have high toxicity levels and contain some carcinogens. Furthermore, organic pesticides often require higher dosages to be effective. 

Suppose you want to reduce the risks associated with pesticide use. In that case, you can make a few DIY recipes that include household ingredients like garlic, vegetable oil, hot peppers, soap, and water. Lastly, take care of your garden and upkeep a healthy environment to prevent pesticide use in the first place. 

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Anat Goldberg

Hi! My name is Anat and I have lived all my life in the countryside. I grew on a farm in Northern Italy and from an early age, I took care of the animals on the farm and the family garden. Over the years I have developed a growing passion for organic cultivation and pest control.

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