Tuesday, January 27, 2009


Sodium Benzoate (E-211) is a well recognized class II preservative used extensively in many low pH foods and beverages to protect against bacteria and fungus. Generally their level in most of the products in which it is permitted, is restricted to 0.1% or less. Credit must go to this wonder chemical for saving billions of rupees worth foods during the last several decades through its preservative action. Now new information emerging from food scientists across the world is showing E-211 as a potential threat to consumers in presence of ascorbic acid when the carcinogenic Benzene is generated under ambient conditions.

As of now there is global limit of 10 parts per billion (PPB) of Benzene under WHO, which is allowed to be in potable water though in EU countries it is as low as 1 ppb. No definite standards have been set so far regarding Benzene limits in food materials. It was in December 1990 that first reports about occurrence of Benzene was reported in two brands of soft drinks and investigations revealed that it was generated in situ from Benzoic Acid in presence of ascorbic acid and the mechanism of action involves the hydroxy radical of ascorbic acid attacking the Benzoic acid, removing CO2 and leaving Benzene in the wake. More disturbing is the fact that exposing the products to heat and light for short periods dramatically increases the benzene concentration. Temperature beyond 30C and exposure to U V lights for several hours can also raise the Benzene levels in such products.

Industry has not covered itself with glory by its attempts to defend presence of Benzene in soft drinks and during early nineties there was voluntary commitment that it would overcome the problem through internal voluntary corrective measures. The defensive stand of soft drink giants like Coca Cola by claiming that even people walking on the side walk can imbibe more Benzene from automobile exhaust fumes does not speak well of their commitment to consumer safety. Further arguing that Benzene limits in potable water is not relevant to foods is also some what far fetched. In UK 230 brands of drinks exceeded the safe limit for Benzene and 4 brands were recalled because they contained benzene several times more than the safe limit (11-28 ppb). Situation is more alarming considering that there are more than 1500 brands of soft drinks containing benzoic acid and ascorbic acid combinations.

Human beings can smell Benzene in the air if the concentration is in the range of 1.5 to 4.7 ppm and in water if it is 0.5-4.5 ppm. Tobacco smoke, automobile emissions, automobile service stations, gas stations and industrial emissions contain Benzene to varying extent. Gasoline contains Benzene 0.7 to 2.06% and evaporated gasoline carries with it Benzene also. A chain smoker is presumed to be imbibing about 1.8 mg of Benzene a day, a high level for causing cancer. In the air, the concentration can be between 0.02 and 34 ppb. The absorbed Benzene reaches bone marrow and body fat and can cause acute myeloid leukamia(AML) in the long term.

Is the Indian consumer also vulnerable to the 'Benzene" risk? Unfortunately reliable data regarding Benzene levels in the air, water or the foods do not seem to be existing to come to any meaningful conclusion. Considering the primitive way the soft drinks are handled, distributed, stored, show cased at the retail level, Indian consumer is much more vulnerable than his western counter part, though all manufacturers may not be using ascorbic acid in their formulations. A comforting thought is that average consumption of soft drinks in India is a fraction of what is consumed in other countries. Benzene can be avoided or reduced considerably by adjusting the level of benzoic acid and ascorbic acid and including EDTA in the recipe. Let us hope that soft drink industry will take timely and adequate steps now itself before being caught unaware and branded as a villain again after the unfortunate pesticide controversy of nineties.


1 comment:

Anonymous said...

After losing someone to leukemia, probably developed from his long hours of exposure to Crude oil vapor in storage tanks, I can only fully agree with this. This is a matter to be taken up seriously by food, oil and chemical industries as well as the environment department.