Aquamid is undergoing an approval process before it can be sold in the US. Already popular in Europe, there is something seductive about it. Aquamid is a "soft" volume filler that is injected to fill out dreaded nasolabial folds, sunken cheeks and wrinkles. It sounds super safe, based on its 97.5% proportion of water. What could be unsafe about injecting oneself with something that makes up 80% of our body?

The thing about Aquamid is that it is considered to be permanent. This is because the other 2.5% is polyacrylamide, which is made from polymerized acrylamide. Polyacrylamide is not harmful, but acrylamide is considered a dangerous neurotoxin. It seems that it is perfectly possible for unpolymerized acryalmide - the poisonous stuff - to turn up in polyacrylamide. And in 1997, there was a research study that claimed that "under normal environmental conditions" (I'm not sure if that includes being inside human skin) it degrades and releases acrylamide.

The manufacturers of polyacrylamide fillers say that they take care to remove the acrylamide neurotoxins and that the polacrylamide is not bio-degradable. The company behind Aquamid, Contura International, has results of a five-year study of 116 patients that demonstrates "good" or "very good" esthetic results with "very few" adverse events.

Nevertheless, there are reports of things going wrong. In 2005, a Danish study looked at 44,000 women who were injected with Aquamid, of which 55 reported adverse reactions (swelling or nodules). 51 of them required treatment. I have found women reporting bacterial infections, weeping solution and swelling as recently as April 2008. A Polish study in 2006 on late stage complications after Aquamid injections was published in Aesthetic Plastic Surgery.

Last month Spanish researchers at a university in Barcelona said that they found infrequent but severe cases of immune-related side effects and that polyacrylamide and water-based injections could no longer be considered safe.