It is a substance present in lower levels such as 0.01%-1%?
This is a relatively broad question that could apply to many different substances. Here are a few examples:
- In cosmetics and skincare products, active ingredients such as retinoids, AHAs, and vitamin C are often formulated at low concentrations of 0.01%-1% to minimize irritation and other side effects.
- Certain impurities in drinking water, such as iron, manganese, and hydrogen sulfide, are considered problematic at levels below 1%. Many municipal water treatment plants aim to reduce these contaminants to levels between 0.01-0.5%.
- Trace elements such as copper, zinc, and chromium are essential micronutrients that are required in small amounts for proper health and nutrition. They are typically present in food and supplements at levels ranging from 0.01% to a few percent.