EWG Risk Score:
What is it:
Sodium Benzoate is a preservative.
Known to be a neurotoxin to aquatic animals. (Source)
Is toxic/lethal at high doses in humans. (Source)
Animal studies have shown some developmental abnormalities (Source)
Rats and mice given moderate doses of sodium benzoate showed decreased weight and some endocrine disruption (Source) however, at low doeses there were no effects.
Animal studies have shown it to be toxic to the liver at moderate doses (Source)
When combined with vitamin C (ascorbic acid) or citric acid, it forms benzene, a known carcinogen. This is a common problem in soft drinks.
One study found that sodium benzoate created free radicals in the body, destorying mitochondrial DNA, adding to the body's aging process. (Source)
Type of products it's in:
Shampoo, conditioner, body wash, face and body lotions, mouthwash
Some Brands that use this ingredient:
Oblige by Nature
Kiss my Face
I am somewhat wary of this ingredient because, on a molecular level, it contains a benzene ring, which gives it the potential to be a xenoestrogen. However, after sifting through hundreds of studies, I haven't found much evidence that it acts that way. It seems as though the body is able to break it down easily and flush out of the system. Studies have deemed it safe as used in cosmetic applications because it's used in small amounts. However, some people may be sensitive to it, and if you are hormonally sensitive or imbalanced, I would limit your exposure as much as you can. Additionally, make sure that there is no Vitamin C present with it, as it can form the carcinogen benzene in its presence. The bottom line is, avoid it if you can, but if you can't find a safer alternative, it's safe in limited amounts. In foods, definitely avoid it. If you've eaten something with vitamin C, and then eat something with sodium benzoate, it can create benzene in your body.