Cosmetic Microbiology | Microbes used in Cosmetics

Cosmetic Microbiology | Microbes used in Cosmetics

Cosmetic products apply externally on human body for cleansing, beautifying, and promoting attractiveness, or altering the appearance without affecting the body’s structure or function. Cosmetic microbiology has become one of the most important field in the world today. Fundamentally, this article focuses the relationship between microorganisms and cosmetics. In cosmetic industry the microbial contamination has been a huge problem. Therefore, there are special rules and regulations to prevent or minimize the presence of toxic microorganisms. But interestingly there are many trending applications of using microorganisms in cosmetics.

Do you know microorganisms can grow on your cosmetics, which can make you ill?

Women in all over the world use make-up to increase their beauty. But most of them don’t know their make-up can contaminate with microorganisms which make them ill after applying. Bacterial, fungal and viral contamination not only occur in foods but also can occur in cosmetic products which can be hazardous for consumer health.

Mascara, eye shadows, foundations, eye liners, face powder, face cream, lotions, shampoo, perfumes and etc. are the commonly using cosmetics. Most of these products contain oils, water, vitamins, sugars and proteins which provide an optimal medium for microbial growth. Also, its neutral pH and favorable storage conditions facilitate their growth.

cosmetic microbiology
Cosmetics makeup - Image by Ichigo121212 from Pixabay

How can cosmetics contaminate?

Mainly the microorganisms can contaminate into the product via hand and mouth. But sometimes the product can already contaminate at the production process, as contaminated raw materials, packing materials or the poor hygiene in the production line. When you are using cosmetics there are several ways that bacteria and fungus can get into it.

  • Using cosmetic jars instead of tubes – Jar has a wide opening so it can contaminate at each time of using by your finger or it can pick up fungal spores floating around the air.
  • Mascara pumping – When applying, the stick of mascara pumps up and down for several times and it passes microbes from eye to tube and back to your eyes.
  • Sneezing while applying – This will directly put bacteria to the open container.
  • Reapplying lipstick after meals – This will contaminate the product with food particles and microorganisms and in the next application they will again spread on lips.
  • Sharing cosmetic products – Eyes are very susceptible to bacteria so sharing can cause contaminations and spread of infections.
  • Dirty make up bag – This will cause for the cross contamination from bag to clean product.
  • Double-dipping brushers – This will mix products together and mix face oils with blushers which can make a suitable environment for microbial growth.

What do microorganisms do after contamination?

  • Microorganisms can grow on cosmetics and spoil it or change the chemical composition of the product by various metabolic reactions which have harmful effects on consumer.
  • Normally cosmetics do not need to sterile but they add preservatives to stop or reduce the microbial growth. Sometimes these preservatives can be absorbed or inactivated by suspended organic component, swelling agents or solubilizes, etc. This can be led to the multiplication of microorganisms and production of toxic compounds which can cause for allergic reactions and skin irritations.

Do you think powders are free from microorganisms because of their low water activity?

No, they can be contaminated with clostridial and fungal spores. Mixture of powders and sweat provides a good medium for the growth of these spores and cause for allergies, acnes and redness in eyes and skin.

Types of bacteria found in cosmetics and their effects

Most of the cosmetic products have a neutral pH which suitable for skin. Therefore, bacteria are the mostly preferred organism in this pH. Usually fungi do not grow in cosmetics because they grow optimally under low pH.

  • Staphylococcus epidermidis – Mainly found on lipsticks, eye shadows and eye liners. They are naturally found on skin as opportunistic pathogens and affect to the people which have a compromised immune system. Some stains are resistant to antibiotics and if not well treated they severely affect the intestine.
  • Staphylococcus warneri – As the previous one, they are also found on skin naturally and cause infections for people with compromised immune system. In extreme cases they can damage the heart valves (endocarditis).
  • Pseudomonas aeruginosa – Commonly found on soil, water and skin. Normally causes rash and inflammation on skin but in serious cases it can cause for severe infections that can lead to organ failures. Also, it can live on mascara wand and cause eye infections.
  • Methicillin-Resistant Staphylococcus aureus (MRSA) – One of the most serious form which present on old make-up. It causes for pink eye disease. Resistant for antibiotics. Enter from pimples and mucous membrane of eye and nose and cause redness inflammation and heat over the infected area.

There are some common types of eye infections which are caused by bacteria in make-up

  • Conjunctivitis – Commonly known as pink eye. Here small blood vessels in the membrane is going to be enlarge and give the pink or red color.
cosmetic microbiology
Photo credit goes to - Banswalhemant / CC BY-SA (
cosmetic microbiology
Photo credit goes to - Gzzz / CC BY-SA (
  • Keratitis – Symptoms are eye drainage, decreased vision, puffy eye lids & light sensitivity. Usually occurs when contact lenses are contaminated with bacteria.
Photo credit goes to - Imrankabirhossain / CC BY-SA (
  • Stye – A small lump in the eyelid. This may be due to the trapping of bacteria inside the meibomian glands and lead for the production of oil inside it.
microbes used in cosmetics
Photo credit goes to - Andre Riemann / Public domain
  • Blepharitis – Mainly caused by Staphylococcus on cosmetics which infect the eye lid. Symptoms : Blurred vision, eye discharge, pain and redness.
Photo credit goes to - clubtable / Public domain

How can we prevent these microbial contaminations on cosmetics?

  • Never use expired cosmetics.
  • Don’t put water or saliva into the mascara bottle.
  • Never pump mascara wand up & down. Instead swirl the brush inside the bottle.
  • When reapplying lipstick after eating wipe off lips completely and reapply it.
  • Keep the make-up bag clean.
  • Use separate brushes for each product.
  • Never use saliva to wet an eye pencil.
  • Use a correct brand that is safe for you.
  • Never sleep with make-up on.
  • If you have any type of skin irritation, allergy, eyelid swelling or red eye because of your cosmetics, immediately stop using them, meet your doctor and have medical advices.

Applications of using microorganisms in cosmetics


BOTOX is the protein or the neurotoxin produced by Clostridium botulinum. Botulinum toxic is extremely harmful and toxic to humans if it is consumed. It can block the neurotransmitters of human body and hence cause botulism or paralysis. Naturally occurring Clostridium botulinum bacteria and their spores are normally harmless. When the bacterial population increases, at a certain point they produce botulinum toxin. It is responsible for the disease called botulism. Some microbiologists have estimated that 1 g of botulinum toxin could kill 1 million people & a couple of kilograms could kill every human on earth.

The same paralysis of muscles is exactly what is desired when using Botox as a cosmetic. Isn’t it SCARY?

When people use it correctly & in small doses, BOTOX is a very effective cosmetic in smoothing out wrinkles in face. And also, BOTOX can help to treat uncontrolled blinking and lazy eye, excessive sweating, & some bladder disorders. There are few commercial versions of botulinum toxins are available in the market;

  • Botox (onabotulinumtoxin A)
  • Dysport (abobotulinumtoxin A)
  • Xeomin (incobotulinumtoxin A)
  • Myobloc (rimabotulinumtoxin B)
  • Jeuveau (prabotulinumtoxin A)

Applications of BOTOX

The primary application of Botox is reducing the appearance of facial wrinkles. According to the American Board of Cosmetic Surgery, Botox injections (treatments) are the most popular cosmetic treatment nationwide. In 2016, around 7 million people had Botox treatments. Generally, BOTOX are using to treat for frown lines (glabellar lines or elevens), wrinkles around the eyes (crow’s feet), Cobblestone skin on the chin, lines at the corners of the mouth, improve the appearance of their hair, and horizontal creases in the forehead.

However, Food and Drug Administration (FDA) has approved Botox for the following uses;

  • Crossed eyes
  • Eyelid spasms
  • Cervical dystonia (neurological movement disorder)
  • Excessive sweating (primary focal hyperhidrosis)

If someone wants to try Botox, they can speak to their healthcare provider about the health and safety risks, and other considerations. 

Vetiver grass essential oil

Perfumes are mixtures of essential oils of plants. What makes them essential? Rather than implying importance, these oils have a distinct pleasant aroma, or essence, allowing them to give perfumes their scent. One plant in particular is cultivated on a large scale to harvest essential oils: Chrysopogon zizanioides or Vetiver grass. For Vetiver grass, the specific essential oil harvested for perfumes is a sesquiterpene. However, this plant may recruit some help when making this oil.

Research has found that microbes may actually play an essential role in the production of these molecules. In fact, Vetiver grass itself only produces incomplete precursors. These precursors are then modified by microbes, associated with the roots of these plants, to produce their final form: the essential oil we want to use in perfumes. Creative changes to the microbes associated with the roots of these plants may enable to easily create new variations of this oil. By modifying the microbes present or altering the genes involved in this process, these new variations could craft with different properties and scents.

Cosmetic microbiology
Vetiver grass - Photo credit goes to - treesftf / CC BY (

Article By,

Pasindu Chamikara – Microbiologist

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