Yoga Mats, Flame Retardants, and Fertility

Yoga Mat Chemicals May Mess With Your Fertility.”  A few months ago, this headline from Forbes popped up in my Google news feed.  As a woman who loves yoga and knows she wants kids in the future, this headline caught my attention.  This is what began my research into yoga mats & natural yoga mats, flame retardants, and fertility. 

Disclaimer:  This post contains affiliate links.  See my Disclosure Policy for more information.

yoga may with title "yoga mats, flame retardants, and fertility"

The focus of the article

The article in Forbes referenced a study published in the Environmental Health Perspectives which explains a link found between exposure to organophosphate flame retardants (PFRs) and decreased fertility.  PFRs are typically applied to polyurethane foams to reduce flammability. 

Researchers studied women who were going to Massachusetts General Hospital Fertility Center for In Vitro Fertilization (IVF) treatment.  The study measured womens’ urine for levels of certain chemicals that are metabolized from PFRs (these chemicals, as a whole, are called “metabolites”).  Which means, when the body comes in contact with PFRs, they process the chemical and produce another chemical which can be detected in urine.  The study then evaluated how many women achieved various stages associated with the IVF treatment: fertilization, implantation, pregnancy, and live birth and compared with their levels of the PFR metabolites.  Trends showed higher PFR metabolite levels equating to lower instances of success with the various stages of the IVF treatment.  

My Takeaway

Correlation and causation are not the same

First, the study and Forbes articles imply that higher PFR levels in a woman’s body increase infertility.  But really, this is just a correlation, which is NOT the same as causation.  Maybe all the women with higher PFR levels were older.  There is also a correlation between a woman’s age and fertility (reference this study).  Or maybe the women with higher PFR levels also smoke – studies correlate that smoking negatively impacts fertility, too.  Additionally, this was a small study in one city.  More studies with a larger and more diverse population could show different correlations. 

PFRs are not used in yoga mats – synthetic or natural yoga mats

Second, the Forbes headline is misleading.  It makes it sound like yoga mats are the only source of the fertility-damaging chemical – the PFRs.  Later in the article, it states that PFRs “are commonly used in yoga mats, sofas, car seats, and other types of polyurethane foam.”  So it’s not just yoga mats (spoiler alert – it’s not in yoga mats at all!), but many other common items that most people in first world countries contact every day. 

I came across this article, which states that one of the authors of the study says that she is not aware of PFR use in yoga mats.  The study never mentioned yoga mats.  Not once. It was just included in the title of the news article.  According to the study, PFRs “have been used widely in the polyurethane foam of upholstered furniture…  [Unlike other flame retardants,] these chemicals [PFRs] are not chemically bonded to foam and have been shown to migrate into the air and dust of indoor environments.”  In more simple English, this means that the PFR type of fire retardant does not stay on the surface on which it was applied, therefore it can easily be inhaled or absorbed through contact with skin.  Being around items treated with PFRs is enough for the PFRs to get into your body. 

So, from the perspective of female fertility, yoga mats are probably fine.  But, be aware (be wary?) of flame retardants, especially PFRs!

yoga mat roll

Natural Yoga Mats

Phew, I am sighing in relief that my yoga mat (probably) isn’t one of the many things in this world negatively affecting my health.  After all, I picked up yoga to positively impact my health!  Yoga makes me feel great mentally and physically.  After the concern that the Forbes article gave me about synthetic chemicals in yoga mats, I decided that I needed to find a yoga mat that made me feel better about its environmental impact.

As I began researching, I found that a LOT of manufacturers claim that their yoga mats are eco friendly.  But most still contain synthetic chemicals – most in the form of some plastic.  One claims to be “free from PVC, phthalates, silicone, latex and other toxic materials.” Sure, I’ll believe all of that, but what is it really made from?  It’s made from TPE: thermoplastic elastomer.  While recyclable, TPE is still plastic – bioaccumulative, synthetic.  The EWG doesn’t specifically talk about TPE plastics, they warn that “the toxicity of plastics is not fully understood or adequately tested.”  That’s enough for for me keep staying away from plastics. 

The moral of this story is: don’t believe everything you read, and do your homework.  Just because the seller or manufacturer’s description says that the product is natural or eco friendly does not make it true.  I always research products before buying them.  Below I talk about three yoga mats that I have researched and believe to be made from safe ingredients. 

Natural yoga mats: natural cork and natural rubber

I found 2 main types of all natural yoga mats: natural rubber and natural cork.  Costs ranged from about $50 to upwards of $100. 

I decided to try one of the least expensive 100% natural yoga mats first.  Fitness Zest sells a yoga mat for $49.99 (as of November 2017).  It is made from natural rubber, which makes it biodegradable.  And, it is advertised as organic, which is even  better in my book. 

I’ve been using this mat for a few months and I am very satisfied with it.  The natural rubber sticks well to hard wood and carpet, but is not so sticky that lint or hair adheres to it.  Unlike my previous cheap plastic yoga mats, when I use the Fitness Zest yoga mat on carpet, it doesn’t stretch much at all.  No longer does my yoga mat turn Warrior into a n undesired split attempt!  I also love that it’s longer than standard yoga mats, 72″ rather than 68″.  Note: the mat does smell like natural rubber.  It doesn’t bother me, but the smell is noticeable.  

The rubber natural yoga mats are really easy to keep clean.  According to the manufacturer’s response on Amazon to the question of cleaning, “…All you need to do is wipe the mat down front and back with a damp cloth or sponge.  You can saturate the sponge with a mild organic cleaner…”  I wet a cloth with water, add a few drops of my liquid castile soap, and wipe down the top surface of the mat. 

natural yoga mat

Three natural yoga mats

My current preferred yoga mat is:

While I have not yet tried any other natural yoga mats, my other front runners were: 

I am sure there are many more good, truly natural yoga mats.  Have you tried one?  Please share in the comments below!

How to wash towels

I recently came across this article in Time and, frankly, was pretty horrified.  I immediately set out to change the way that I clean my towels.  Something that really, truly cleans the towels, but is still environmentally friendly.  After a bit of research and testing, I came up with this routine and method to wash towels.

Disclaimer:  This post contains affiliate links.  See my Disclosure Policy for more information.

Title How to Wash Towels Thoroughly

Towels get gross, fast

I had always assumed that since I used a towel after washing my hands or body, that the towel stayed pretty clean.  I was not thinking about the fact that crazy amounts of bacteria live on your skin all the time – even after you’ve just soaped up in the shower or scrubbed your hands.  As the Time article states, this is because most people do not thoroughly scrub their hands every time. So, when you dry your body and hands, you transfer the bacteria onto the towel.  Where the bacteria can multiply, because towels stay moist for a while.  Not to mention, most towels are kept in bathrooms/near toilets, so every time you flush the toilet, bacteria and microorganisms spread onto pretty much all surfaces.  Ok, that is graphic enough for this post.  Sorry.  I hope you weren’t eating while reading this.

Anyway.  Towels become pretty gross, pretty quickly.  I believe staying healthy helps one to be “green” and frugal.  Seriously, I struggle with non-(synthetic) cehmical options for treating ailments, and I go though way too many tissues when I get sick!  So I needed a good, environmentally friendly way to clean my towels.

How to clean

First, I always wash towels separately from clothing, because I clean them differently than regular clothes.  My post with the laundry detergent recipe talks about how I wash clothes.   

A microbiologist interviewed for the Time article recommends washing with hot water and oxygenated bleach.  Which most people know as the active ingredient in Oxy Clean. 

Oxygen Bleach

Oxygenated bleach can be liquid or powder.  Liquid has a shelf life of only a few months, or less.  Powdered is more stable, with a shelf life of a couple years,  So I decided to use powdered form.  Note that, when oxygenated bleach breaks down, the resultant products are quite safe: liquid becomes oxygen and water, powdered becomes oxygen and natural soda ash (also known as washing soda, or sodium carbonate).  So there is no danger to the break down, but the product becomes ineffective at cleaning the way that oxygen bleach cleans

OxiClean Baby & LA’s

I searched the Environmental Working Group Consumer Guide for cleaning to find a healthy and safe oxygenated bleach.  I found two that have only two ingredients: sodium carbonate peroxyhydrate (also called sodium percarbonate) (the ingredient that releases oxygen when in contact with water), and sodium carbonate (washing soda, or soda ash).  These two are OxiClean Baby and LA’s Totally Awesome Oxygen Base Cleaner.  However, I located some of LA’s Totally Awesome Oxygen Base Cleaner, and it definitely has more than 2 ingredients.  It has fragrance.  I contacted the manufacturer and they sent me the Material Safety Data Sheet.  The cleaner contains a 3rd ingredient: Ethoxylated Alcohol.  Which has an EWG rating of C

OxiClean Baby & LA's Totally Awesome Oxygen Base Cleaner
OxiClean Baby & LA’s Totally Awesome. Note that LA’s is an off-white rather than bright white color, and has colored particles. OxiClean Baby is pure bright white.

My choice of oxygen bleach is:

Sodium percarbonate & sodium carbonate

Additionally, you can purchase sodium carbonate peroxyhydrate/sodium percarbonate by itself and sodium carbonate (Super Washing Soda) by itself.  The reason that oxygen cleaners contain sodium carbonate is that it makes the water alkaline (basic), which helps the sodium carbonate peroxyhydrate (and washing soaps) clean.  According to the MSDS that I found for OxiClean Baby, it’s 50-60% Sodium carbonate peroxyhydrate, and 40-50% sodium carbonate.  If you’re mixing your own, roughly half sodium carbonate peroxyhydrate and half sodium carbonate should work well.

I currently use OxiClean Baby because it was the only EWG A rated oxygen cleaner that I came across and was able to verify ingredients with the manufacturer.  From here on, when I reference “oxiclean,” I am referring to OxiClean Baby or simply sodium percarbonate mixed with sodium carbonate.

OxiClean Baby package, front

OxiClean Baby package, back

How to wash with oxygen bleach

Per guidance from the scientists in the Time article, I wash towels with hot water and oxygenated bleach, and I let the towels soak in the hot water with detergent and oxygen bleach for at least 1 hour or overnight.  If I had a washing machine that allowed soaking, I would scoop OxiClean to about half full (between the 2nd or 3rd line – per the package instructions) into the washer, pour 2-3 Tbsp of my liquid laundry detergent into the washer, and fill with hot water.  Once the washer was partly filled, I would add towels, allow to finish filling, then let soak for at least 1 hour or overnight.

OxiClean Baby
OxiClean Baby. The provided scoop is filled halfway, containing about 60 grams.

But, my Maytag Ecoconserve washer does not allow you to soak anything in it.  In fact, if you try to trick it by letting it fill, then “pause” the cycle, after about 15 minutes the washer automatically drains.  And there is no way to stop it.  I’m not going to lie.  I felt really guilty for wasting 26 gallons of water the day that I discovered this.  I stood there watching the water drain.  Trying, and failing, to figure out a way to stop it.  Sometimes I really hate this new “smart” technology.  Anyone want to trade me their old reliable washer for my shiny new “smart” one?  I digress.  Sorry.

soaking towels

So, with my washer that does not let me soak, I either just run the cycle immediately and the towels “soak” about 20-30 minutes during the full and wash cycle, or I soak outside my washer.  Usually I do the latter, using a big plastic tote into which I dissolve the OxiClean in water, add towels, cover with water, and let soak.  I then put detergent in my washer, load the towels into the washer, and machine wash my towels.

washing towels

Drying towels

The Time article recommends high heat drying as an additional method for killing bacteria and pathogens.  I elect for a compromise between the energy usage of high heat setting on a washing machine and the very environmentally friendly method of air drying.  I hang towels to dry, then  tumble on a medium heat setting (which to me feels very hot) for about 5 minutes.  Based on USDA guidelines for cooking food to high enough temperatures to kill bacteria then letting “rest” 2-3 minutes, I think my 5 minutes in the dryer is good enough for my purposes. 

towels air drying
towels air drying

How often to clean

The microbiologist interviewed for the Time article recommends washing kitchen and bathroom towels after 2 days of use, especially if there are young children in the house.  I recommend that you follow the guidance of these professionals.  

But, in case you’re wondering, here’s what I do.  Since I currently live in a household with only (mostly) responsible adults, I stretch it a bit.  First, I wash my hands thoroughly to remove as many bacteria and microorganisms as possible.  My kitchen and bath towels go in the laundry every 3 days.  My hand towels in the bathroom get used for 2-3 days, then get turned around.  Basically, when I dry my hands, I only use the part of the towel on the side of the towel bar nearest to me.  The back half of the towel barely gets wet.  So I guess (I need a good way to check this! I smell science experiment…) that the back half of the towel stays pretty clean, so that flipping it around gives me a mostly “new,” clean towel.  Then after another 2-3 days, the hand towels go in the laundry.  


OxiClean Baby

OxyClean Baby costs about $10 for 3 pounds ($3.33/lb) on Amazon and at Walmart. 3 lbs = 1,362 grams. 1 scoop filled halfway = 60 grams.  1362grams/60grams/scoop=22.7 scoops (loads of towels) per package. $10/22.7loads=$0.44 per load. (50-60% Sodium carbonate peroxyhydrate, so each half-scoop has 30-36 grams)

LA’s Totally Awesome Oxygen Based Cleaner

I do not recommend LA’s Totally Awesome Oxygen Based Cleaner due to the ingredient list.  But, if you choose to use it, it’s a great price.  I found it at Dollar Tree for only $1 per pound. 1 scoop weighs approximately 30 grams.  16oz=454grams/30 grams/scoop=~15 scoops.  Per package instructions, 1 load of towels uses 2 scoops, so 1 package =~ 7.5 loads of towels.  $1.07/7.5=$0.14 per load.

But, the active ingredient, sodium carbonate peroxyhydrate, is only 8-14%.  To get the same amount of sodium carbonate peroxyhydrate as a 1/2 scoop of OxiClean Baby, you’d need about 5 times as may scoops as the LA’s Totally Awesome package recommends. 2 scoops = 60 g x 5 = 300 g x 8% = 24 g to 300 g x 14% = 42 g.  $0.14×5=$0.70, so OxiClean Baby is better cost per active ingredient sodium carbonate peroxyhydrate.)

Sodium Perchlorate plus Sodium Chlorate

Pure sodium perchlorate is $13.50 for 5 pounds ($2.70/lb).  Using 30 grams per load: 5 lbs = 2268 grams. 2268g/30g=75.6 “servings” per package. $13.5/75.6=$0.18

Sodium chlorate, or Super Washing Soda, is about $5 for 55oz at Walmart or a local grocery store. Using 30 grams per load: 55 oz = 1559 g. 1559g/30g=52 “servings” per package. $5/52=$0.10. 

Using 30 grams each sodium perchlorate and sodium chlorate, cost per load is $0.18+$0.10=$0.28. 


Based on my calculations using amount of each ingredient per product, the lowest cost oxygen bleach cleaner is mixing your own sodium perchlorate and sodium chlorate, costing $0.28 per load of towels.  However, OxiClean Baby comes pre-mixed with its own scoop, and costs $0.44 per load of towels. 


Do you have any environmentally gently towel washing techniques?  Please share in the comments below!