The tetrasodium EDTA is a chelating agent, which serves to react and form complexes with metal ions which could affect stability and / or appearance of cosmetics. It “seizes” the metals, but doing so makes them available to be dissolved in water. Then the residue of cosmetics that end up in water cause an increase in metals already present in them. And it derivate the poisoning of marine life (and who eats it … mercury levels in fish are more than a concern!).
Although this substance is so controversial – Ecolabel a brand in Europe do not allow its use for example – the tetrasodium EDTA continues to be used.
The reasons have been explained by Fabrizio Zago, an industrial chemical that is also consultant of Ecolabel: “The official reason” is that acting as sequestering it reduces water hardness and then let surfactants (including soap to work better. The specific reason for the presence in soaps is that sequesters iron ions that otherwise will cause rancidity of the soap itself with production of bad smell. In liquids products, emulsions and so on instead this EDTA is introduced because it is a good adjuvant of preservative system that breaks down the microbial although not defined as “antibacterial” or “biocidal”. One will wonder then if can not be replaced : “It depends from case to case: the liquid sequestering action can be supported by sodium citrate (but you will not have the antibacterial effect), in soaps the less polluting choice is the sodium etidronate, without, again, bactericidal action.
“Natural” substances that will be able to do everything that EDTA do not exists or I do not know them but a mixture of substances can make all the functions of EDTA alone. But since it costs so little and really works, you will not find any traditional industry of cosmetic willing to give it up. ”
We lovers of nature already know it, so let’s do our action, let’s read the composition of what we buy and do not buy anymore cosmetics having this EDTA, a clear message can be given to traditional cosmetic industries if suddenly their sales decrease!.