Chemicals in Cotton Clothes: Should We Be Concerned?

Although plastic-based fabrics dominate the fashion industry, cotton remains popular among those seeking a more sustainable fabric. Many people believe cotton is the most natural material. In reality, it is one of the most contaminated crops in the world.

According to the U.S. Department of Agriculture, 42 million pounds of pesticides were used annually in conventional cotton production from 2019 to 2023. Most of these chemicals are considered toxic.

Only a few of us consider the impact this has on our well-being as we wear cotton clothes daily. Here, we will explore whether the cotton clothing industry is damaging our health.

Chemicals used in cotton farming

Cotton is grown in more than 50 countries, but the U.S. ranks among the top three producers. At least 98 pesticides were used on conventional cotton in the country in 2021. Only 10 of them accounted for 86% of all reported pesticides that year by weight:

Pesticide	Usage by weight	Potential harm
Glyphosate	30%	Considered probably carcinogenic to humans by the World Health Organisation
Ethephon	20%	Has the potential to cause severe skin and eye irritation
Dicamba	9%	Low in toxicity, however, skin irritation may develop
Acephate	6%	Possible human carcinogen based on mouse studies showing increased liver and adrenal gland tumors
Tribufos	5%	Classified as likely to be carcinogenic to humans, based on studies showing tumors in mice
Paraquat	4%	Highly toxic and poses severe, often fatal, dangers to humans and animals
S-metolachlor	3%	Poses potential liver damage and is classified as a possible carcinogen
Glufosinate-ammonium	3%	When ingested, it may cause severe neurological, respiratory, and cardiovascular effects
Acetochlor	2%	Has carcinogenic potential due to links to lung, liver, and nasal tumors in animal studies
Trifluralin	2%	Possible human carcinogen with potential for liver and kidney damage

Chemical harm to cotton farm workers

According to a 2020 systematic review of 157 publications, the farming population is approximately 860 million people. Every year, 44% of those farmers are poisoned.

Cotton farming is not an exception. A 2023 study surveyed 585 cotton farmers in Burkina Faso. Researchers compared self-reported health outcomes between 353 conventional and 232 organic cotton farmers.

Both groups reported health problems after pesticide exposure, but rates were much higher among conventional farmers:

Health effects reported by farmers	Conventional farmers experiencing at least one symptom	Organic farmers experiencing at least one symptom
Neurological symptoms (severe headaches, dizziness, or trembling)	314 (88.95%)	113 (48.71%)
Respiratory symptoms (rhinitis, persistent cough, or tightness in the chest)	311 (88.10%)	157 (67.67%)
Skin effects (irritations or burns)	301 (85.27%)	152 (65.52%)
Irregular heartbeats	233 (66.00%)	58 (25.00%)
Digestive symptoms (abdominal pain, nausea, vomiting, or diarrhea)	206 (58.36%)	114 (49.14%)
Urinary symptoms (pain or foamy urine)	142 (40.23%)	37 (15.95%)

Another 2025 study surveyed Tanzanian conventional cotton farmers and found that nearly half (48%) experienced negative side effects from pesticide exposure in the past 12 months.

Sadly, deaths also occur. In 2017, after intense pesticide spraying in western India, 800 people were hospitalized, and around 50 people died.

Do chemicals stay in cotton after farming?

The answer to this question is more complicated than it seems. Online searches show varying answers. Most sites state that pesticides used in cotton farming can persist in the fabric and may harm health.

“Not all farming and processing chemicals fully wash out during manufacturing,” says Stacy Grace, a Sustainability Expert and a Co-Founder of Plastic-Free Underwear Brand KENT, “In conventional cotton, trace residues of pesticides can persist at low levels.”

However, scientific evidence on this topic is harder to find. A 2004 study by the Technical University of Lodz tested 20 cotton samples from various regions.

They found that the most contaminated samples came from Uzbekistan, but traces of pesticides were also detected in U.S. cotton samples. That said, researchers note that the levels of pesticides found meet safety standards and should not pose a risk to health.

However, another study indicates that detecting residual pesticides on cotton is technically demanding and traditional laboratory methods are often too expensive, complex, and require trained personnel.

Manufacturing chemicals

Before it reaches store shelves, cotton is affected by both farming and manufacturing chemicals. The textile industry uses chemicals such as toxic metals, flame retardants, dyes, waterproofing, and flexibility agents.

Grace warns that ‘natural’ doesn’t automatically mean clean. “Finishing treatments like formaldehyde-based resins or certain azo dyes may remain, particularly when there’s no rigorous third-party testing in place,” she adds.

Some substances improve manufacturing, while others add new properties to the fabric. When these substances come into contact with the skin, they may be absorbed, causing skin irritation or other side effects.

Apart from that, Grace suggests that there’s growing discussion around cumulative, long-term exposure to certain synthetic finishes and how they interact with skin over time:

“There’s more and more attention on endocrine disruptor chemicals — things like certain phthalates, byproducts from some azo dyes, and PFAS — which are often used in finishing fabrics. Studies are showing that they can interfere with our hormones and are being linked to potential effects on reproduction, metabolism, and overall hormone balance. It doesn’t mean our cotton shirts are immediately bad, but it does add to the bigger conversation about cumulative, everyday chemical load.”

Formaldehyde

In the mid-1920s, formaldehyde was introduced into the textile industry to increase fabric resistance to wrinkling during wear. Today, it is one of the most used chemicals: from paper coatings and cosmetics to furniture and textiles.

Like many substances, it is potentially toxic. A 2022 study examined 120 first-layer textile items usually worn by pregnant women, babies, and toddlers. Researchers found that 20% of these items contained formaldehyde.

They noted that exposure to these clothes may contribute to irritation, allergic reactions, eczema, and other dermatitis symptoms. Even though it is considered a carcinogenic chemical, the study indicates that the main reason for formaldehyde-related cancer risk is inhalation, not skin contact.

Azo dyes

Azo textile dyes, common in clothing, can break down into aromatic amines that may have negative side effects.

A 2017 study found that out of 397 potential aromatic amines, around 40 were identified as mutagenic, meaning they may cause DNA changes. 22 were found to be linked to increased cancer risk.

Some dyes, such as benzidine-related dyes, are regulated by the U.S. Environmental Protection Agency (EPA). Manufacturers must inform the EPA 90 days before using a chemical that may be restricted.

However, unlike the European Union, which prohibits entire classes of azo dyes in clothing, the U.S. doesn’t have an equivalent, comprehensive rule focused on azo dyes in textiles.

Getting rid of chemicals from cotton clothes

You bought the t-shirt or jeans you have been dreaming of, but you worry that manufacturing chemicals may irritate your skin. Here are some tips Grace recommends to remove chemical residues from your clothes:

• Wash before wearing, since new garments often release the highest residues.
• Use warm water with a gentle detergent to help remove surface finishes.
• Air out new clothing before first use, as “off-gassing” can continue after manufacturing.

Studies also show washing is effective. For example, the previous 2022 study on formaldehyde residues in clothing found that after washing, none of the garments contained the chemical.

Is organic cotton a better choice?

In 2024, the first International Fairtrade Textile Forum took place in Paris. Fairtrade India presented a study comparing organic, converting to organic, and conventional cotton farming. These are the findings they spoke about:

• Fairtrade organic cotton generates 45% less greenhouse gas emissions. For every hectare, which is about the size of a soccer field, organic cotton creates about 1,900 lbs of CO2 emissions. Conventional cotton creates about 3,446 lbs of CO2 emissions.
• Among Fairtrade organic and in-conversion farmers, 96% avoid using chemical pesticides entirely.
• Fairtrade organic and in-conversion farmers get 20% more cotton per unit of water used.
• Only 5% of Fairtrade organic and in-conversion farmers use synthetic nitrogenous fertilisers, compared to more than nine out of ten conventional farmers.

Why are farmers not switching to organic cotton farming?

Switching from conventional to organic cotton farming can be difficult, and there are several reasons some farmers decide not to do it:

• It takes about three years to certify a farm as organic. During this process, farmers experience lower yields without receiving the higher organic premium price.
• Without chemical fertilizers or pesticides, crops are more vulnerable to pests and weeds.
• Organic farming requires intensive manual labor for weeding and pest management, increasing operating costs.
• Finding suitable, high-quality, GMO-free seeds can be difficult.

How to choose cotton clothes?

Grace recommends looking for Global Organic Textile Standard (GOTS) certification: “Organic cotton is grown without synthetic pesticides and, when certified, processed under stricter chemical standards.” She notes that GOTS certification ensures that clothes are:

• Without toxic heavy metals like lead in dyes and pigments
• Strictly limited to formaldehyde-based finishes
• Without toxic azo dyes that can release carcinogenic amines
• Without GMOs in the cotton crop
• Without chlorine bleaching in processing

However, most of the fashion industry uses conventional cotton. Even for that one, there is a certification you can look for. Oeko-Tex ensures that your clothing has been tested against a list of 1,000 harmful substances.

Final word

Conventional cotton undergoes intensive chemical treatment, from pesticides used during farming to finishing agents during manufacturing. Some residues from long-term exposure may interfere with your health. However, broader research is needed.

Even if research shows that chemical residues can be removed during washing, it is recommended to seek cotton clothing made with safe materials. The best way to do that is to look for GOTS or Oeko-Tex certification to ensure the highest quality, especially for people with sensitive skin.