Furore over ‘toxic’ preservatives’ use in soft drinks

A recent Lagos High Court judgment has raised fresh concerns over the health dangers of preservatives used in food products in Nigeria.

The Court ordered the National Agency for Food and Drug Administration and Control (NAFDAC) to ensure that the Nigeria Bottling Company (NBC) puts warning on its products-Fanta and Sprite- that mixing them with vitamin C can be toxic to human health because they contain the preservative, sodium benzoate (the salt of benzoic acid).

Sodium benzoate is most widely used in acidic foods such as salad dressings (vinegar), carbonated drinks such as soda, jams and fruit juices, pickles (vinegar), condiments, such a mustard, ketchup, chocolate bars, dips, salsa, shredded cheese and even the cosmetic products such as mouthwash, toothpaste, cough syrup, creams and lotions, and in medicines.

The preservatives increase shelf life and maintain freshness of food, beverages and cosmetics.

Shelf life is the length of time that a commodity may be stored without becoming unfit for use, consumption, or sale. In other words, it might refer to whether a commodity should no longer be on a pantry shelf (unfit for use), or just no longer on a supermarket shelf (unfit for sale, but not yet unfit for use).

NAFDAC, the British Food Standards Agency (FSA) and the United States Food and Drug Administration (FDA) have considered sodium benzoate safe if taken in stipulated concentration but many researches suggest different results.

Several studies including the International Agency for Research on Cancer (IARC) of the World Health Organisation (WHO) have confirmed that soft drinks containing a mixture of the salt of benzoic acid, sodium benzoate and vitamin C can cause cancer and other chronic conditions. However, FDA claims that sodium benzoate is safe because it is used in very low amount to preserve foods and as long as it is not combined with Vitamin C or E. It forms benzene in the presence of vitamin C and E, or in an acidic environment. Benzene is a strong known carcinogen.

According to Wikipedia, benzene in soft drinks is of potential concern due to the carcinogenic nature of the benzene molecule. This contamination is a public health concern and has caused significant outcry among environmental and health advocates. Benzene levels are regulated in drinking water nationally and internationally, and in bottled water in the United States, but only informally in soft drinks. The benzene forms from decarboxylation of the preservative benzoic acid in the presence of ascorbic acid (vitamin C) and metal ions (iron and copper) that act as catalysts, especially under heat and light.

The President of Nutrition Society of Nigeria (PSN), Dr. Bartholomew Brai, confirmed the Wikipedia assertion, to journalists. The nutritionist, however, said that the possibilities of the reaction-taking place to form benzene are rare. However, sodium benzoate is not banned in any country, in fact Codex approves it for use in soft drinks at levels not more than 600mg/kg.

The Codex Alimentarius or “Food Code” was established by the Food and Agricultural Organisation (FAO) and WHO in 1963 to develop harmonised international food standards, which protect consumer health and promote fair practices in food trade.

In Nigeria, a Review Committee set up by the Federal Ministry of Health adopted 300mg/kg as the maximum recommended level of benzoic acid for soft drinks compared to 150mg/kg in the United Kingdom (U.K.).

Consultant Nutritionist and Dietician, Scientific and Regulatory Director, Central, East &West Africa, Coca Cola, and Chairman, Technical Committee of the Association of Food Beverage and Tobacco Employers, AFBTE, Fred Chiazor, told journalists in Lagos, on Tuesday, that a review committee conducted a nationwide survey on benzene in soft drinks and found insignificant quantities. The review committee concluded that soft drinks sold in Nigeria are safe for human consumption.

Meanwhile, according to Codex, signs of benzene toxicity are nausea, vomiting and abdominal pain. Lethality (for both inhaled and ingested benzene) has been attributed to respiratory arrest, central nervous system depression, or suspected cardiac collapse.

IARC noted that human exposure to benzene has been associated with a range of acute and long-term adverse health effects and diseases, including cancer and aplastic anaemia. “Benzene causes acute myeloid leukaemia (acute non-lymphocytic leukaemia), and there is limited evidence that benzene may also cause acute and chronic lymphocytic leukaemia, non-Hodgkin’s lymphoma and multiple myeloma.”

Other controversial food preservatives include: Tartrazine: A synthetic dye mixed with blue dyes to create green that is found in sweets, soft drinks, ice cream, and fish fingers. It is linked to allergic reactions, anxiety, migraine, and blurred vision. Said to cause hyperactivity in children when mixed with benzoic acid. It is banned in Norway and Austria.

Quinoline Yellow: It is a synthetic dye derived from coal tar. Also used in cosmetics and as pigment for tattoos. It is found in sweets, and soft drinks; and can lead to children’s tantrums and hyperactivity. It is banned in Norway, United States, Japan and Australia.

Allura Red: It is coal-tar-derived dye, often mixed with yellow dyes for orange shades that is found in sweets, soft drinks, and condiments. It is linked to adverse reactions in those allergic to aspirin and hyperactivity in children. It is banned in Norway and Austria.

Sunset Yellow: It is coal tar dye found in sweets, yoghurts, and cheap jam. It is blamed for triggering stomach upsets and skin irritations. Has also been linked to hyperactivity in children. It is banned in Norway, Sweden and Finland.

Carmoisine: It is a coal tar dye found in sweets, yoghurts, and ices. People allergic to aspirin are said to suffer rashes and water retention. Believed to cause hyperactivity and Attention-deficit/hyperactivity disorder (ADHD) in children. It is banned in Norway Sweden, United States and Japan
Ponceau 4R: It is derived from coal tar and found in sweets, tinned fruits, jellies, desserts, and cough medicines. Asthmatics and people allergic to aspirin may suffer adverse effects. Believed to cause hyperactivity in children. It is banned in Norway and United States.

Meanwhile, besides the Lagos High Court ruling, researchers have found that the preservative can cause kidney damage. A study on “Effect of Benzoic Acid and Combination of Benzoic with Citric Acid as Food Additives on the Renal Function of Experimental Rats” concluded: “In conclusion both benzoic acid and combination of benzoic with citric acid, increases serum creatinine and urea nitrogen levels, that lead to inflammation and damage to kidneys indicating impaired renal function.”

The study was published in Asian Journal of Clinical Nutrition.

The researchers further stated: “Chemical food additives may affect normal human body metabolism, organ function or may be precipitated in body tissues, leading to different types of adverse reactions. Benzoic acid has no adverse effects in humans at doses of 650-800 mg kg-1 body weight per day. In combination with ascorbic acid, sodium benzoate and potassium benzoate may form benzene, a known carcinogen. Heat, light and storage can affect the rate at which benzene is formed. Benzoic acid and its biphenol derivatives can be absorbed into a lipid bilayer and thus can modify the gel to liquid crystal phase transition to the lipid vesicles. For this, some foods, particularly fruits and vegetables, are believed to have protective effects against cardiovascular disease and cancer due to the presence of antioxidant hydroxyaromatic compounds. Lipoic acid inhibits glycine conjugation of benzoic acid in the liver, resulting in reduced clearance of benzoic acid from blood, which leads to decreased excretion of benzoylglycine in urine.

“In the recent years the kidney failure appeared among wide sectors of the population in Sudan. Benzoate salts as food additives implied in food industries may have responsibility to this problem. This study was conducted to investigate on the effect of benzoic acid and benzoic plus citric acid on the renal function of the white American rats.”

Also, the Asthma and Allergy Foundation of America states that significant numbers of people report allergic reactions to the compound. The American Beverage Association reports another significant problem with the preservative in drinks.

Sodium benzoate, also known as E211, is a major ingredient in diet soft drinks. The Center for Science in the Public Interest reports that benzoic acid has properties similar to E211 and also creates allergy problems, hives and aggravation of asthma conditions.

Diet Coke made by Coca-Cola does not contain sodium benzoate, a change that was made voluntarily by the company in 2008. Coca-Cola’s other drinks, including Fanta and Sprite, continue to use E211 in production. The company states that alternatives to E211 impact preservation and change the taste of the product. Pepsi Max, as well as the diet versions of Mountain Dew, Sunkist Orange, Nestea and Nordic Mist, also continues to use the preservative throughout the world.

Diet Coke, Diet Pepsi and Lipton Diet Iced Tea have shifted to potassium benzoate and citric acid to act as preservatives in both canned and plastic-bottled soft drinks.

Some, but not all, commercial soft drink companies use sodium benzoate as a preservative. Pepsi does not have the ingredient, while Dr. Pepper uses E211 for soft drinks bottled in plastic containers but not in aluminum cans. Mountain Dew in all forms of packaging uses E211 in addition to other preservatives including erythorbic acid and calcium disodium EDTA. Dr. Pepper specialty drinks, including cherry vanilla soda, berries and cream, and cherry soda, and all contain sodium benzoate. 7 UP products shifted from sodium benzoate to use potassium benzoate and vitamin E acetate as preservatives.

Carbonated soda water and tonic water drinks, including drinks produced under the Schweppes brand, also use sodium benzoate as a preservative. Sugar- and fruit-flavored waters such as Nestle’s fruit and water drinks and Saratoga brand Ripple Water drinks also include E211 as ingredients.