Various chilli powder products, believed to be contaminated with this substance, are now being removed from South African shop shelves - for the second time in two years. The last scare was in March 2005.
In addition, local authorities have been requested to sample all other chilli powders and related products, according to Sapa reports.
"Where any Sudan dyes are detected, the relevant products should be removed from the shelves and destroyed," the health department said two years ago. Supermarkets have obviously not adhered to this.
What is Sudan Red?
Sudan dyes belong to a family of industrial dyes normally used for colouring plastics and other synthetic materials, according to a document published by the European Union.
In South Africa, the colorant is prohibited for use in food products by the Regulations Relating to Food Colorants (R.1008) of the Foodstuffs, Cosmetics and Disinfectant Act 54 of 1972. The only permissible colorants that may be used in sauces, seasoning and condiments are: Beetroot Red, Allura Red, Azorubine or Carmoisine, Ponceau 4R or Cochineal Red and Carminic Acid.
During the previous scare in 2005, four Sudan dyes were detected in food products around the world, in particular Sudan I (Sudan Red) and Sudan IV (Scarlet Red).
Sudan Red is used to colour substances like petrol, oil and shoe polish.
Why the dyes are used in food
Authorities suspect that Sudan dyes are being used to enhance and maintain the colour of the food products to which it is added.
The perception is that colour intensity is an indication of quality. The dyes prevent products from losing their colour over time.
What are the health implications?
Sudan I to IV may have potential carcinogenic (or cancer-causing) effects.
Research indicates that Sudan I-IV is split into amines after intake and that some amines, which may be formed during the splitting of the Sudan dyes, are classified as carcinogenic.
According to the International Agency for Research on Cancer, Sudan I may have a genotoxic effect. Genotoxic chemicals are capable of causing damage to DNA. Such damage can potentially lead to the formation of malignant tumours, but DNA damage does not necessarily lead to the creation of cancerous cells.
However, Sudan I has been linked to a dose-related higher incidence of neoplastic liver nodules, which are precursors to cancer, in rats. In mice, an increased incidence of leukaemia and lymphomas was observed.
Studies have shown that this dye may also exert sensitising effects through skin exposure or inhalation.
Given their mechanism of action, health authorities have not been able to identify safety levels for Sudan dyes or been able to quantify the risk.
Research suggests that the risks increase with frequent or ongoing consumption.
Which local products have been implicated?
Tests on five products is currently underway and the results would be released once the process has been finalised.
These products include: Osman's Taj Mahal Extra Special Chilli Powder, Osman's Taj Mahal Extra Special Curry Powder (medium), Ma's Spices Curry Powder, Adamson Spices Hot Curry Powder and Shaikh's Exotics Peri-Peri Sauce.
Should you be concerned?
Consumers who have been using contaminated products may now be worried about its potential ill effects.
But the Department of Health assured consumers two years ago that the situation "did not pose any immediate health risk". The substance will only exert a harmful effect if taken in large quantities over a prolonged period of time.
The best course of action is for consumers to dispose of previously purchased products.
Health24 will be monitoring the current crisis and keep our users informed.
– (Carine van Rooyen, Health24)
The Sudan Red food scare