PPM is not a new term in the skincare industry, and it sounds sophisticated, doesn't it? What does PPM mean and stand for? Don't worry, trust us, it's not that complicated!

What is PPM ?

PPM stands for parts per million. It is a type of measurement unit of concentration. It represents part of the total number in units of 1/1,000,000 (million). It is a unit that is more commonly used in the laboratory.

It's not as complicated as you may think.

Let’s take some examples.

We have 110,000ppm of Centella Asiatica and 10,000ppm of Tea tree leaf water.

What does it mean? Let’s get down to the equation!

110,000ppm = 110,000/1,000,000 = 0.11 = 11%

So it means that 110,000ppm of Centella Asiatica is equal to 11% of Centella Asiatica, where there are 110,000 parts of Centella Asiatica in one million molecules.

Let’s have another example from the same products 10,000ppm Tea tree

10,000ppm = 10,000/1,000,000 = 0.01 = 1%

So it means that 10,000 ppm is equal to 1% of Tea Tree leaf extract. It contains 10,000 Tea Tree Leaf Extract in one million of the solution!

Yes, it's that simple! So it's like having the stated amount of molecule within a million part of other inactive ingredients or usually solvent. This is a unit that is commonly used in the laboratory. However, it is not a general unit for skincare labelling.

When do people use PPM or percentage (%)

Since the skincare label is relatively unregulated, brands can state their concentration in either PPM or percentages. Sometimes, putting on the word ppm instead of percentage (%) can make it sound more sophisticated.

Is the larger number of ppm, the better?

Every ingredient has its "optimum" range of usage on skincare products to cause adequate or optimum changes on the skin. There's no specific scientific evidence to prove the most effective concentration of each ingredient in ppm.

Sometimes, even a large number of certain ingredients in a product can be found to be redundant. Let's take an example of ascorbic acid, commonly known as vitamin C. Only 200,000 or 20% of ascorbic acid is found to be effective for topical skincare. Concentrations above 200,000 or 20% do not contribute to any antioxidant, anti-ageing, and pigment-reducing benefits. Therefore the maximum amount of concentration of Vitamin C 20% or 200,000 is found to be optimum for topical skin care products.

Why is knowing the concentration important?

Knowing the ingredients' concentration can help you understand how different concentrations can affect your skin differently. Sometimes it's' the dose that makes the poison. Sometimes people can tolerate a certain amount of specific ingredients in their product. When a product mentions its ingredients and their concentration, you can filter out the products based on your skin tolerance to the concentration of the ingredients.

Takeaway: The large number of PPM is commonly misinterpreted and misunderstood. We hope you can understand and interpret them better after reading this article. The equation is straightforward indeed!

- By Claudia Christin (@funskincare)

MBBS, Ph.D. (Dermatology)