Over the course of the "better living through chemistry" era, we have seen the impact of synthetic chemicals on the world around us.
Complex ecosystems don't respond to single chemicals in predictable ways ... when we spray DDT into an ecosystem to remove mosquitos, we succeed in obliterating the bulk of the small insects, but we will then start to see unintended consequences in the long term. Birds lay eggs with thin shells and fish accumulate DDT to toxic levels and so on. Although we achieve our short-term goals, the long-term effects are not easy to live with.
Skin is now understood as an ecosystem. Human cells and microbes co-exist with both contributing to optimum skin health. Skin can often have an even greater microbial diversity than the gut.
Many people apply synthetic chemicals to skin to achieve short-term goals ... but are they prepared for the long-term effects?
In 2015, a 3D molecular map of human skin chemistry was made for the first time. The subjects were asked to stop using all personal care products for three days to avoid contamination of the results. The assumption was that the majority of the chemistry would be from microbial origin and that the bulk of the rest would be of human origin, with environmental chemicals making up a small but measurable portion.
The results didn't follow that pattern.
Products of microbial cells contributed around 1% of the chemistry. Human cells contributed around 0,5%. Residues from personal care products contributed 8% of the measured chemistry. The rest of the chemistry was not in the chemical libraries.
We now know that our knowledge of skin chemistry is a long way from complete, and yet we're prepared to risk the addition of synthetic chemicals that are not known to exist in nature.
The long-term effects of synthetic chemicals on the skin are not yet known but it seems unlikely that they would improve long-term ageing outcomes.
Click here to view the full study: Molecular Map of Skin
Molecular cartography of the human skin surface in 3D
Amina Bouslimani et al.; PNAS Plus, March 6, 2015