Manufacturers of sunless tanning products claim DHA is a simple carbohydrate sugar solution, but some toxicologists disagree. Several years ago, Dr. Thomas Pierce, a toxicologist who investigated the harmful effects of some tanning beds, issued a warning that DHA is not as simple or harmless as it may seem.
In an interview, Dr. Pierce once said: "It is not an ingestible sugar, and no one should be eating it."
Part of the problem is that the U.S. government's regulations for DHA allow contaminants such as lead, arsenic and mercury. Lead in particular is known to affect brain development, and no one knows how large the effect may be on your baby, should you be pregnant while spray tanning.
If you are pregnant or nursing, I would urge you to stay away from spray tanning for this reason alone. A report by the National Toxicology Program suggests the risks of DHA remain unclear, pointing to some evidence that DHA may be a mutagen that could induce breaks in DNA strands. Another issue is absorption through your skin. You shouldn't put anything on your skin you wouldn't feel safe eating. You can however ingest 100% Herbal Instant Tan, this is how you know it's TRULY chemical Free and safe for you and your skin!! It's the best self tanner for people concerned about their health.
Absorbing chemicals transdermally is actually MORE dangerous than ingesting them orally, because they can be absorbed directly into your bloodstream without any digestive degradation. Digestive acid works, at least in part, to neutralize some chemicals—but this does not occur when you absorb them transdermally, or inhale them, for that matter. For example, by taking a seven-minute shower you are exposed to more chlorine, DPBs, and VOCs than by drinking a gallon of the same tap water.
A study performed by the Skin Absorption and Metabolism Section of the FDA, published in the 2004 issue of Toxicology and Applied Pharmacology, found as much as 22 percent of the DHA could be absorbed through your skin, as opposed to merely laying on its surface.
This is additional evidence that what you put ON you, goes IN you.
But when you have DHA-containing products sprayed on you in a booth, little droplets become suspended in the air all around you, increasing your risk for exposure through your eyes, nose and mouth. Wearing protective gear over your eyes, nose and mouth is extremely important—but it does not remove all the risk.