Non-Toxic Bath Stones and Bath Mats

Frequently Asked Questions About Bath Stones and Non-Toxic Bath Mats

Does a healthy bath mat matter?

Bath mats seem innocent, but can cause two main health issues:

First, they can be dirtier than the toilet, simply because they are often overlooked, underwashed, and close to all the action (toileting, bare feet, etc.) If you're not washing it at least once weekly, it's harboring dirt, mold, fungus, bacteria, and the urine and fecal particles that escape into the air and settle in to the fibers when the toilet is flushed. All of these lovely bath mat inhabitants can quickly start to smell, perhaps increasing your desire to use synthetic fragrances. Super fast-drying bath mats are important to reduce your exposure to all of the above.

Second, many standard bath mats are made with harmful azo dyes and other fabric-processing chemicals that your bare feet and body come into contact with, or have endocrine-disrupting antimicrobial treatments or water-resistant PFAS coatings applied. Some have a memory foam core, bringing unnecessary foam issues into your bathroom, and finally, some have PVC backing for skid resistance that off-gasses VOCs into the bathroom. In a small room with limited air flow, where your goal is to get cleaner, healthier, and ideally even relaxed, these chemicals add unnecessary complication.

Diatomaceous Earth “Stone” Bath Mats

What is diatomaceous earth?

Diatomaceous earth is a natural powder that comes from the fossils of skeletons of tiny organisms called diatoms. Their skeletons are made of silica, which is a safe and common natural material found in rocks and the Earth's crust.

How does diatomaceous earth evaporate so quickly?

Diatomaceous earth can absorb up to 3 times its weight in water, and because it has so many micropores, it also evaporates that water up into the air extremely quickly.

What are bath stones made of?

Bath stones are typically made from diatomaceous earth, often combined with other natural materials like vermiculite (a mineral), quartz sand, or recycled paper pulp. The diatomaceous earth itself is what gives bath stones their signature quick-drying properties—it's super porous and absorbs water rapidly, then evaporates moisture back into the air just as fast.

Do bath stones really work?

Yes, bath stones work really well — I have one! They dry your feet quickly and stay dry themselves, very magically. This means you step out of the shower onto a dry surface, and the stone is ready for the next person almost immediately. Because they don't stay wet, bath stones don't develop the mold, mildew, and bacterial growth that plague traditional fabric bath mats.

Are bath stones better than regular bath mats?

Bath stones have several advantages over traditional fabric bath mats:

• They dry almost instantly, eliminating the damp, musty smell that fabric mats develop between washes, and reducing your desire to use synthetic fragrances in the bathroom.

• They don't require laundering, which saves time and reduces exposure to laundry detergent residues.

• They're naturally antimicrobial because bacteria and mold need moisture to grow, and bath stones don't stay wet.

Some of the drawbacks: they can be more expensive up front, require some light sandpapering every few months to maintain absorbency, and lower quality ones are prone to cracking with pressure or dropping. That said, I’ve had the same one for 4 years and with 3x yearly sanding, it has stayed very absorbent, not cracked, and I haven’t had to wash and dry a bath mat in the laundry this whole time!

Are diatomaceous earth bath mats safe?

Yes, diatomaceous earth bath mats are safe for typical bathroom use. The silica in diatomaceous earth is a natural material found in rocks and sand.

The health concerns around diatomaceous earth relate specifically to inhaling the fine powder if you are in silica manufacturing, or if you're grinding your bath stone into powder (why you would do this, I do not know.) Using a bath stone mat as intended (stepping on it with wet feet) poses no inhalation risk. The stone stays intact and doesn't release dust into your bathroom air.

How long do bath stones last?

Bath stones typically last 1-3 years depending on use, care, and quality. The main factors that shorten lifespan are cracking (from drops or impacts), developing stains that won't sand out, or gradual breakdown of the porous structure. You'll know it's time to replace your bath stone when it stops absorbing water as quickly, develops deep cracks, or becomes permanently stained.

Can you stand on a bath stone with dirty feet?

You can, but it's not ideal. Bath stones absorb whatever touches them, including dirt, soap residue, and oils from your feet. Unlike fabric mats that you can toss in the washing machine, bath stones require manual cleaning. If you regularly step on your bath stone with dirty feet, you'll need to scrub and sand it more frequently to prevent staining and maintain absorption. For best results, rinse your feet before stepping onto the stone, or at minimum, give the stone a quick rinse and wipe after particularly dirty use.

How do you clean a diatomaceous earth bath mat?

Cleaning a diatomaceous earth bath mat is simple but requires a little scrubbing. For routine maintenance, wipe the surface with a damp cloth weekly to remove any soap scum or residue. For deeper cleaning, gently scrub with water and a soft brush, then let it air dry completely (usually 10-30 minutes). For stubborn stains or to refresh absorption, lightly sand the surface with fine-grit sandpaper (220-400 grit) to expose fresh porous material underneath. Never put bath stones in the dishwasher or soak them for extended periods, as this can break down the binding materials.

Do bath stones get moldy?

Bath stones are highly resistant to mold because they dry so quickly that mold doesn't have the sustained moisture it needs to grow. Traditional fabric bath mats stay damp for hours or even days between uses, creating perfect conditions for mold and mildew. Bath stones evaporate water within minutes, so mold can't establish itself. However, if you place a bath stone in an extremely humid, poorly ventilated bathroom where it never fully dries, or if you leave it sitting in standing water, mold could theoretically develop. Under normal use, mold on bath stones is exceptionally rare.

Can bath stones crack or break?

Yes, bath stones can crack or break if dropped on hard tile or concrete floors. Avoid dropping heavy objects on them or using them as stepping stools. Small surface cracks won't affect function, but deep cracks that go all the way through can cause the stone to break apart. I’ve had mine for 4 years and it hasn’t cracked or broken because it just sits there flat on the floor, and is high quality. Read reviews carefully, as durability can vary brand to brand quite a bit, with some cracking easily.

Do bath stones stain easily?

Bath stones can develop stains from soap residue, hard water minerals, personal care products, or dirt tracked in from outside. Light stains often fade as the stone dries, and many can be removed by wiping with a damp cloth or gently scrubbing. Stubborn stains can be sanded away with fine-grit sandpaper, which removes the top layer and exposes fresh material underneath. Dark-colored bath stones hide stains better than light ones. To minimize staining, rinse soap off your feet before stepping on the stone and wipe it down weekly.

Can you use bath stones on heated bathroom floors?

Yes, you can use bath stones on heated bathroom floors without any issues. The gentle warmth from radiant floor heating won't damage the stone or affect its absorption properties. In fact, heated floors can help bath stones dry even faster by increasing evaporation rates. Just make sure the stone sits flat on the floor surface for even heat distribution. Avoid placing bath stones directly on extremely hot surfaces (like directly over a heating vent), as rapid temperature changes could potentially cause cracking.

Are bath stones slippery when wet?

No, bath stones typically have good traction even when wet because the porous diatomaceous earth surface provides grip. However, smooth tile or stone floors around the bath mat can still be slippery, so the bath stone should be placed on a stable, level surface. Some bath stones come with rubber or cork backing to prevent sliding on smooth floors. If your bath stone slides around, you can add thin rubber grip pads underneath to keep it in place without affecting drainage or drying time.

What size bath stone should I buy?

Bath stone size depends on your bathroom layout and how many people use the space. Standard sizes are roughly 24" x 16" for single users or small bathrooms, and 30" x 18" or larger for shared bathrooms or if you prefer more standing room. Smaller stones (around 16" x 12") work for kids' bathrooms or as a secondary mat near the sink. Measure your available floor space and consider how you step out of the shower—you want enough surface area to comfortably stand with both feet. Larger stones are more expensive but reduce the chance of stepping onto wet tile.

Can you cut or trim a bath stone to fit your space?

You can technically cut some bath stones using a hand saw or oscillating tool, but it's tricky and risks cracking. The porous material tends to crumble along cut edges, and you'll create a lot of fine dust (wear a mask if you attempt this). Some bath stone materials are denser and cut more cleanly than others. If you need a custom size, it's usually better to look for brands that offer multiple size options or arrange smaller stones side-by-side rather than attempting to cut one. If you must cut, score the surface first, work slowly, and accept that the cut edge won't be perfectly smooth.

What is the best bath mat for mold prevention?

Bath stones made from diatomaceous earth are the best option for mold prevention because they dry within minutes, eliminating the moisture mold needs to grow. Wooden bath mats with slatted designs are the second-best option—they dry much faster than fabric due to airflow but not as quickly as stone. Traditional fabric bath mats, even organic cotton ones, are the most prone to mold because they stay damp for hours and trap moisture in their fibers. If you're struggling with bathroom mold, switching to a bath stone or wooden mat can make a dramatic difference.

Wooden Bath Mats

Are wooden bath mats better than bath stones?

Wooden bath mats and bath stones each have advantages. Wooden mats like teak or beech are more forgiving underfoot, won't crack if dropped, and have a warm, natural aesthetic. They dry faster than fabric mats due to air circulation between slats, though not as instantly as bath stones.

However, wood requires more maintenance—it needs periodic maintenance to prevent cracking and warping, and water can pool between slats if the bathroom isn't well-ventilated.

I recommend a wooden bath mat if you have a fast-drying well-ventilated bathroom, live in a warm climate, or have a bathroom floor that drains or is acceptable to have some moisture on before it evaporates.

Organic Fabric Bath Mats

Are there organic bath mats without toxic chemicals?

Yes, organic cotton bath mats certified by GOTS (Global Organic Textile Standard) are made without toxic pesticides, harsh dyes, or chemical treatments. OEKO TEX certification is also a good option to look for— though less strict than GOTS, it still ensures the bath mat has been tested for harmful chemicals. This is really important because many standard bath mats have coatings applied to the fibers to make them more water, stain, or bacteria-resistant, but these coatings have harmful health effects (PFAS and synthetic antimicrobials are both endocrine disruptors.)