Sodium Benzoate Side Effect

Sodium benzoate Side effect

While Sodium benzoate is generally recognized as safe in small doses, Sodium benzoate may cause harmful health effects under certain conditions.

It is probably safe, right? After all, the US Food and Drug Administration (FDA) and the Canadian Health Protection Branch have pronounced this chemical preservative to be acceptable when consumed in low amounts.


The most concerned side effects are carcinogenic. A more common problem, however, is the combination of sodium benzoate and citric acid and/or ascorbic acid (vitamin C). When these ingredients get together, they form benzene, a cancer-causing chemical associated with leukemia and other blood cancers.

For example, a small percentage of people are hypersensitive to sodium benzoate and can experience asthmatic attacks, hives, or other allergic reactions when they consume the preservative.

Is sodium benzoate bad?

Sodium Benzoate was found to be present in 34% of 204 tested products (92 shampoos, 61 conditioners, 34 liquid soaps, and 17 wet tissues) (Yazar et al. 2010).  Though the FDA limits the use of sodium benzoate to 0.1% by weight in food, it is limited to 2.5% in rinse off products and 0.5% in leave on products by the European Union Cosmetic Directive (Yazar et al. 2010).  Though Sodium Benzoate is generally considered safe, it can become a serious hazard if it is combined with Vitamin C (ascorbic acid) or Vitamin E (tocopherols) as they react to form benzene (C6H6), a cancer causing hydrocarbon.  The amount of benzene produced from these reactions was determined to be below dangerous levels (5 parts per billion) for consumption by the World Health Organization, based on presence of benzene in soft drinks.  Benzene is classified as an A1 carcinogen (confirmed for humans) by the American Conference of Governmental Industrial Hygienists (ACGIH) and Group 1 carcinogen by the International Agency for Research on Cancer (IARC).  Benzene is also a possible mutagen and developmental toxin in humans that is specifically toxic to blood, bone marrow, and the central nervous system, and may target the liver and urinary system.  Limited studies show that after dermal (skin) exposure, benzene was metabolized by the liver and excreted.  There is no available research on the formation and concentration of benzene in cosmetic products at this time, so it is best to avoid products containing sodium benzoate in conjunction with ascorbic acid (Vitamin A) or tocopherol (Vitamin E).

Is Sodium benzoate safe to pregnancy?

Animal studies revealed prenatal exposure of offspring to sodium benzoate produced lesions in layer 5 cortical pyramidal cells. However, specific animal reproduction and fertility impairment studies have not been conducted. US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the sodium benzoate in pregnant women despite potential risks.

sodium benzoate should be used by pregnant women only if clearly needed. US FDA pregnancy category: C Comments: It is unknown whether this drug can cause fetal harm or can affect reproduction capacity.

Is Sodium benzoate safe to children?

Another consideration is a possible link between sodium benzoate and ADHD (attention deficit/hyperactivity disorder). The Mayo Clinic notes that the preservative (as well as several food dyes) may enhance or trigger hyperactivity in children.

Is Sodium benzoate safe in skin care?

Sodium Benzoate is a salt of Benzoic Acid and used as a preservative in cosmetics and personal care product formulas as a fragrance ingredient, masking ingredient, anti-corrosive agent, and most frequently, as a preservative.

It is FDA approved and has received the GRAS (Generally Recognized as Safe) rating, and the CIR found that doses used in cosmetics and personal care products were not high enough to cause potential reproductive and developmental effects.

The Cosmetics Database still found concerns regarding cancer, developmental and reproductive toxicity, organ system toxicity, irritation and biochemical cellular changes with Sodium Benzoate as an ingredient in cosmetics and personal care products. One or more animal studies showed brain and nervous system effects at moderate doses, broad systemic effects at low doses, and in vitro tests on mammalian cells showed positive mutation results. One or more animal studies showed biochemical changes at high doses where the human health implications are not yet well understood, and animal studies showed skin irritation at high doses as well.

Commonly reported side effects of Sodium benzoate

Include: infection, respiratory tract disease, central nervous system disease, disorder of lymphatic system, hematologic disease, nutrition disorder, and vomiting. Other side effects include: cerebral edema, convulsions, metabolic acidosis, vascular disease, altered mental status, anemia, cardiac disorder, disorder of integument, fever, hyperammonemia, hyperglycemia, hypokalemia, hypotension, mental disorders, and renal disease. See below for a comprehensive list of adverse effects.

How to avoid Sodium Benzoate?

Sodium benzoate is also used to health and beauty products such as mouthwash, shampoo, body lotions, and deodorant to prevent bacteria from contaminating these items. Over-the-counter and prescription drugs such as pills, cough syrups, and topical medications also can contain sodium benzoate.

What you should do?

If you want to avoid sodium benzoate, read labels carefully. Look for the words “benzoic acid,” “benzene,” “sodium benzoate,” or “benzoate,” especially if you also see “citric acid,” “ascorbic acid,” or “vitamin C.” Sodium benzoate is also known as E211.