AO+ Mist Subscription

Live probiotic spray for the skin.
3.4 fl oz - TSA Compliant

Subscribe Monthly or Quarterly.

Clinically researched:

Restores balance to dry, oily, and sensitive skin types.

Improves skin clarity by 35% in 4 weeks.

Improves the look and feel of dry and uneven skin by 35% in 4 weeks.

Reduces dependence on products like deodorants, moisturizers, and makeup.

Preservative-free. No added fragrance. Family-friendly. Sensitive skin-friendly.

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We've long believed that bacteria on the skin are harmful.

As we've gotten "cleaner", we're having more problems with our skin.


Just like our gut needs good bacteria to be healthy, the same is true for our skin.

Shake, Shake, Shake

Shake bottle before each use.

Pick Your Areas

Anywhere you sweat is great.

Pick Your Times

Misting once a day or more. Here are some ideas:



• Restores Natural Balance

• Improves oily & dry skin

• Helps sensitive skin

• Skin is softer, smoother

Only 4 Ingredients

Aqua (water), Nitrosomonas
eutropha, disodium phosphate, magnesium chloride
(natural salts).

More about the AOB
Strain: Nitrosomonas eutropha
No fragrance or scent

US Patent 7820420

We don't use preservatives in any of our formulas, and we source pure, unpreserved raw ingredients.

Because preservatives function to prevent bacterial growth in formulas. On the skin, they have a big impact on the bacterial ecosystem.
Shelf life

Because we don't use
preservatives, our products have a
shelf life.

The AO+ Mist is the only product that may require refrigeration due to the live AOBs. Whether you refrigerate or not will depend on how quickly you use a bottle.

Best used by:
Refrigerated: within 6 months
Room temp: within 4 weeks

AOBs can do something no other active ingredient can:

They convert ammonia into beneficial byproducts. In fact, everywhere in nature with ammonia, there's also AOBs, except modern human skin, where it was wiped out due to modern hygiene.

When we reintroduce AOBs to
the skin, they have a
"peacekeeper" effect:

• By consuming ammonia they help keep a healthy pH on our skin.

• Plus, it's byproducts help calm the skin & keep other microorganisms in check.

It's not just about skin care, it's
about skin health.

This is why our research partner, AOBiome, is dedicated to clinical research on AOBs as a treatment for skin disorders.

Our mission is to develop products that restore and nurture the skin biome. To do this, we had to develop strict criteria and processes for ingredient selection, formulation, packaging, and manufacturing.

We use AOB as our core measurement for testing biome-friendliness. Here's what that means: AOB are one of the most sensitive microorganisms on our skin. Because of this, we believe by formulating a product that's friendly to AOB means that it will also be friendly to the other delicate microorganisms of the biome as well.

We've developed a patent-pending assay that we use to screen all our ingredients and the final formula to ensure that it's A-OK for AOBs.
One of our early findings was that preservatives have a negative affect on AOB. This shouldn't be surprising because preservatives exist for the sole purpose of preventing bacteria and other microorganisms from growing in products. No wonder AOB didn't do well with preservatives, and why you won't find them in our formulas.

In theory, the motivation for including preservatives is a good one, but at the time, we didn't know what potential effect preservatives have on our skin biome. This is a new factor to consider.
This goes beyond our screening process. When sourcing ingredients, we've found many raw materials on their own already come with a preservative. We had to be very careful about our process to make sure we were always starting with unpreserved raw materials.
We develop products that nurture and feed a living ecosystem, without ingredients meant to inhibit or kill. This is why our products all come with an expiration date that's counted in weeks, not years.
We had to recreate parts of this process. We manufacture and package our products with strict criteria to ensure that they are 100% pure when they arrive at your door.

Our packaging is selected for maximal protection of the product inside, requiring us to use pharmaceutical grade packaging for products like the AO+ Mist. We include an expiration date on each product so that you know when to discard them.
Learn more about our forumaltion process and products at
Do I need to refrigerate it?
We recommend storing your mist in the refrigerator prior to first use. Refrigerating your AO+ Mist will keep it potent and active for 6 months.

Once you open your AO+ Mist, it's OK to leave it at room temperature, and keep it handy for use. After 4 weeks at room temperature, the bacteria will start to lose activity. Most people find that it takes them 3 - 4 weeks to use a bottle of AO+ Mist.

What if my AO+ Mist arrives and it's warm or hot?
While Mother Dirt shipments may not always arrive feeling very cold, they should not be very warm or hot either. The bacteria can withstand higher temps (remember they come from nature where some temperatures reach very high), but we do take precautions with our packaging to protect the product from extreme temperatures encountered in-transit (such as sitting in a truck on a hot day).

What if the AO+ Mist doesn't work for me?
We know that everyone's microbiome is unique, and as a result, not everyone will respond the same way. Let us know if it's not working for you and we'll issue a refund.

Can I continue to use soap and other products while using the AO+ Mist?
Yes. We'll never recommend that you abandon products you love. (Some of us at Mother Dirt still stick by our favorite conditioner, makeup, and natural deodorant.) We encourage you to experiment and see what works best for you. As best practice, we recommend applying the AO+ Mist as the very last step in your skincare routine, after all other products have had a moment to absorb.

Mother Dirt Shampoo and Face & Body Cleanser were designed specifically to be compatible with the AO+ Mist, and most off-the-shelf products are not considered biome-friendly. Some oils, such as coconut oil, are biome-friendly (as long as they are preservative and added-fragrance free), and will not harm the good bacteria on the skin.

Is the AO+ Mist okay to use on my kids?
The AO+ Mist and Mother Dirt products are safe for use on children and babies. Our ingredients are on each of the product pages, please feel free to run them by a pediatrician or doctor if you would like.

What if I want to remove the AO+ Mist from my skin once I've applied it?
If for any reason you would like to remove the AO+Mist from the skin, it can easily be removed with conventional soap and warm water.

Does the AO+ Mist have a scent?
The AO+ Mist has no scent.

Shake the bottle before every use to evenly disperse the AOB before spraying. We recommend misting twice daily or as needed, especially after showers or before sweaty activities. Focus on sweat-prone areas like the head, face, groin, underarms, hands, and feet. The AO+ Mist is not a replacement for soap. Instead, it should be used after bathing, before bedtime, or whenever else you find convenient. Feel free to experiment! If you’re using with other topical products, use the AO+ Mist as the last step after everything else has absorbed.

A reduced dependence on conventional products like soap, deodorants and moisturizers, as well as more hydrated, balanced, less-irritated and less-oily skin. These results are supported by our cosmetic clinical study. Remember to experiment: everyone’s microbiome is different, so additional benefits can display in different ways.

Full Ingredients List:

Water, live cultured ammonia-oxidizing bacteria (AOB), disodium phosphate, magnesium chloride.

Learn more:

Live cultured ammonia-oxidizing bacteria (AOB): This is our patented strain of live cultured Nitrosomonas bacteria (Nitrosomonas D23), a type of Ammonia-Oxidizing-Bacteria. Nitrosomonas is a form of “good bacteria” that is able to live on our skin because they consume the ammonia and urea in the sweat on our skin and convert it into beneficial byproducts (nitrite and nitric oxide).

Disodium phosphate: An inorganic salt, buffering agent, pH adjuster and a key component of the buffer solution that the AOB thrive in.

Magnesium chloride: An inorganic salt that is a key component of the buffer solution that the AOB thrive in.

Water: Helps dissolve the salts and keeps the AOBs in a sustainable medium for delivery to the skin.

3.4 fluid ounces. Each bottle is TSA compliant for travel.

Each bottle of the AO+ Mist contains about 550 sprays. At a rate of 20 sprays/day, we’ve found that a bottle lasts about a month for most users. Because everyone’s microbiome is unique, we encourage you to experiment to find what works best for you. Some find that using less or more is better for their routine.