Do non-iron clothing cause cancer?
March 25, 2021•1,811 words
Reading time: 8 min
Follow-up to: Buy non-iron clothing to save ironing time
In the process of verifying information from writing the above piece, came across this:
A quick search on multiple search engines led me to find the following in the top results:
- that formaldehyde is a horrible chemical used to preserve dead bodies and causes cancer
- non-iron clothing is soaked in it during manufacturing
- non-iron clothing is non-environmentally friendly
To start with, these articles I found cited no sources or links to any studies related to formaldehyde exposure in non-iron clothing and cancer, let alone any causative link between wearing non-iron clothing and cancer, but whatever.
I would like to address these. I do not want to get these wrong, as this would actually do harm to others. And we must "do not harm" ('nonmaleficence' in health care ethics). Hence why my posts these two days are late and cluttered with citations.
What is formaldehyde?
Formaldehyde is a naturally occurring chemical substance used in the manufacturing of many things including machines, plastics, woods, carpets, and clothing.
It is used to preserve biological tissue and recognized by multiple authorities as either a 'probably human carcinogen' or a 'known human carcinogen' (probably causes or known to cause cancer). Formaldehyde is also capable of causing respiratory irritation, eye irritation, and skin allergic reactions.
Where is formaldehyde found?
It's in the air, in car exhaust, in the coffee you drank this morning, in fruits and vegetables (American Chemistry Council, 2020), in your beer/wine (Jendral et al., 2011), in your (e-)cigarette smoke (Salamenca et al., 2018), in your cosmetics (Hauksson et al., 2016), in your furniture (Nedorost et al., 2010)...
We ourselves produce it. Formaldehyde is formed and metabolised inside our body (Burgos-Barragan et al., 2017). It's no less 'natural' than the other chemical reactions happening inside your body to sustain your life. Formaldehyde doesn't accumulate and is ultimately converted into water and carbon dioxide and removed by your body (Trincado et al., 2018) (e.g. by breathing or urinating).
(My sarcastic) conclusion: It's in anything and everything and we should all panic.
Should I be concerned?
A word from toxicology
Something to consider is this important principle in toxicology (the study of adverse effects of chemicals on a lifeform):
The dose makes the poison.
It's not the substance that inherently harms us. It's how much of it we're exposed to.
Anything and everything can be a poison. The most poisonous, carcinogenic substance can be harmless it we are exposed to a minuscule quantity of it, while generally harmless substances are deadly given a sufficient quantity of it (The dose makes the poison, 2011).
For example, the potentially dangerous chemical dihydrogen monoxide is something we expose ourselves to every day. It's in our drinks, our food, our homes, our rivers, the air, etc. and sufficient exposure to it can cause poisoning and death.
Dihydrogen monoxide, among other things, can do the following:
"contributes to the "greenhouse effect".
may cause severe burns.
contributes to the erosion of our natural landscape.
accelerates corrosion and rusting of many metals.
may cause electrical failures and decreased effectiveness of automobile brakes.
has been found in excised tumors of terminal cancer patients."
See this for what else dihydrogen monoxide can do.
(Calm down. Dihydrogen monoxide is just water, H2O. Jokes aside...)
We can get poisoning from drinking too much water (see 'water poisoning'). Excessive water drinking causes electrolyte disturbances within our body which can affect our brain, nervous system, and blood pressure among others (Peechakara & Gupta, 2020).
We can also get skin allergic reactions from water (Wassef et al., 2017), (see aquagenic urticaria).
So, is water dangerous? No, not for most reasonable people under normal every day circumstances. The same applies for formaldehyde.
So, the question now is:
How much formaldehyde am I exposed to by wearing non-iron clothing? Is it enough to cause harm?
Formaldehyde in non-iron clothing
Commercial products we use at home only release a very small amount of formaldehyde.
Studies (Nikle et al., 2019; GAO, 2010; Niculescu, 2012) indicate that most clothing, including ones that are likely treated by formaldehyde have either undetectable levels of formaldehyde, or low levels of formaldehyde (acceptable by strict regulatory standards).
- The biggest health risk concern for formaldehyde in clothing is allergic contact dermatitis (allergic reaction), which a small proportion of the (US) population may experience (GAO, 2010), not cancer.
- Most clothing fabrics contain too little formaldehyde to cause primary sensitization* (Nedorost et al., 2010), but those regularly exposed to formaldehyde in the workplace (i.e. already experienced primary sensitization*) may experience contact dermatitis upon wearing non-iron clothing (Carlson et al., 2004)
- Only chronic inhalation exposure to formaldehyde may cause cancer (GAO, 2010). People who work at a textiles plant (or other plants involving manufacturing with formaldehyde) should be concerned about this. (Case/cohort studies have suggested that this is the case.)
- Formaldehyde is readily soluble in water (National Center for Biotechnology Information, 2021). Wash your clothing before wear it. Any left will be insignificant for your health- people smoking near you and drinking alcohol is arguably a bigger concern (with ethanol being the most important carcinogen in alcoholic beverages, not methanol or its metabolic product, formaldehyde) (Lachenmeier et al., 2012)
- Our body DOES clear formaldehyde on its own, ultimately converting it carbon dioxide and water (Burgos-Barragan et al., 2017). We metabolise methanol (e.g. formed in wine due to an enzyme naturally in grapes) in the same metabolic pathway.
- Keep your indoor living/working environments ventilated to reduce indoor exposure (Kaden et al., 2010) (which you should be doing anyway to prevent respiratory diseases (cough influenza and COVID-19, cough) (don't actually cough everywhere, please).
- Light also quickly converts formaldehyde in air into carbon dioxide via photo-oxidation (Kaden et al., 2010).
Those who are highly concerned can avoid these products, but as recommended by the American Cancer Society (2014):
"because the amount of formaldehyde released from these products is low, it isn’t clear that this will provide any health benefit."
Non-iron Clothing and Environmentally Friendliness
First of all, it's not just the production process or chemicals involved that inherently makes something non-environmentally friendly. What you do with the product—how you use the clothing and how long you use it for—matters.
Fast fashion, the practice of mass producing clothing (at decreasing quality accompanied by increasing number of purchases by consumers) is extremely harmful for the environnment.
Cotton as a substitute?
In my reading of the initial articles I found, 'use organic cotton' tends to be the top suggested alternative to non-iron clothing.
However, cotton plants are inherently water and pesticide-intensive to grow.
In this study by Shen et at. (2010) concludes the following:
"Cotton has the highest fresh water ecotoxicity and terrestrial ecotoxicity mainly due to pesticides use" [among the fibres studied (Viscose, Modal, Tencel, cotton, PET and PP)].
What matters is how you then use the cotton shirt.
Energy usage from ironing
Caring for your clothes after they're manufactured and purchased also matters.
The World Wildlife Fund (2013) argues that not ironing your clothes saves a lot of energy:
"One load of washing uses 40 gallons of water. One load of drying uses 5 times more energy than washing. In fact, skipping the ironing and drying of your t-shirt, saves a third of its carbon footprint."
What we SHOULD do
The real problem is the quantity of clothing we go through. The amount of clothing produced and thrown away at blazing speeds is completely unsustainable.
Purely changing the material is not the solution. (Also consider how treated or synthetic materials might last longer, allowing you to use the clothing for longer.)
We must change our consumer behaviour. Here is what we can do to help reduce our clothing environmental footprint:
- Use clothing for a long period of time before throwing them away.
- Avoid buying clothing unnecessarily or purely to follow fashion trends.
- Avoid drying machines and ironing if possible.
- Reuse (upcycle) our cloth.
- If upcycling is not possible, recycle.
If after reading this:
you feel concerned about having formaldehyde in your clothing near your skin and/or find that they irritate your skin (allergic reaction) and/or like ironing and/or don't like (the feel of) non-iron clothing, then don't wear non-iron clothing.
you feel that formaldehyde in your clothing is not really a concern and/or you don't like spending time on ironing, then consider non-iron clothing.
I hope this article will help you make your own well-informed decision.
After all this research, I think the insignificant amount of formaldehyde in non-iron clothing is of no big concern.
I personally will keep wearing non-iron shirts, and will recommend you keep wearing them if you like them.
Detailing some studies
(In case you are interested.)
'n' is the number of clothing tested (i.e. the sample size).
"Formaldehyde Release From Clothing and Upholstery Fabrics Using the Chromotropic Acid Method" (Nikle et al., 2019)
n=77 + 22 (99)
All tested negative for formaldehyde.
"GAO-10-875 Formaldehyde in Textiles: While Levels in Clothing Generally Appear to Be Low, Allergic Contact Dermatitis Is a Health Issue for Some People" (GAO, 2010)
n=165 + 15 (180)
Selected items that were likely to be treated with formaldehyde (for durable press)
Most items either had undetectable levels of formaldehyde or low levels of formaldehyde.
Most meet the most stringent regulatory standards. 10 exceed these regulatory limits.
"Evaluations of formaldehyde emissions in clothing textiles" (Niculescu et al., 2012)
For the European Union (Romanian market)
A small % (1.2 to 1.9%) of textile products for children / women / men exceed the acceptable limits for formaldehyde.
Some caution about this data (I noted this myself and the authors of the studies also note this):
- n = 99, 180 and 161 are not that high and may not be representative of all the fabrics and clothings out there
- Some of these are localized studies and not applicable globally. Although, one details the originating country of manufacturing.
- The sampling method for this (not random sampling) makes the results less generalizable to all fabrics and clothing out there.
Also, some asterisks
*One underlying mechanism in your body behind allergies involves 'IgE' (immunoglobulin E) antibodies (type I hypersensitivity reaction). For an allergic reaction to occur, you need a 'primary' (first) exposure to the allergen e.g. in your workplace (if you work at a chemical/textile plant, for example). Your body produces IgE antibodies which binds to the allergen. The antibody then also binds to inflammatory cells in your body. On second exposure (e.g. from clothing), your 'sensitised' inflammatory cells will cause inflammation and itching (an allergic reaction).