|The amount of colourant, used to impart colour to almost all cosmetic products, varies with colour, product and brand. BIS has set limits for heavy metals in synthetic, organic and natural colourants|
Both organic and inorganic colourants may contain heavy metals as impurity
Colourants are used to impart colour to almost all cosmetic products. Primarily they are of two types:
• Organic colourants such as dyes and organic pigments which are fairly soluble and lakes which are fairly insoluble
•Inorganic colourants lack a carbon molecule. They are composed of fairly insoluble metallic compounds which are either derived from natural sources or are synthesised, like iron oxide and titanium dioxide
Both organic and inorganic colourants can carry heavy metals as impurity. Hence, they are regulated by authorities to ensure that they are safe and the level of impurity is not beyond a limit to harm health.
The amount of colourant in cosmetics varies with colour, product and brand. Lipsticks could have about 10-15 per cent of these, out of which up to half of it could be organic. The composition differs with shade, brightness and other properties.
In the US, heavy metal impurities are individually mentioned for allowed colourants. Bureau of Indian Standards has set limits for heavy metals in synthetic organic and natural colourants:
• Total heavy metal limit (excluding Lead): 100 ppm
• Lead: 20 ppm
• Arsenic: 2ppm
In India, colourants are typically mentioned as colour index number and/or by name on inner and outer product labels.