The UK-based Institute of Food Science & Technology (IFST), through its Public Affairs and Technical & Legislative Committees, has authorised an Information Statement on 3-MCPD (3-monochloropropane-1,2-diol).
Originally classified as a genotoxic carcinogen with the recommendation that its presence in foodstuffs should be reduced to an undetectable level, the European Commission's Scientific Committee on Food (SCF) is promoting a threshold-based approach for TDI and now recommends a provisional TDI level of 2mcg/kg body weight/day for 3-MCPD (3-monochloropropane-1,2-diol). The TDI was adopted on 8 March 2001 and applies from 5 April 2002.
3-MCPD may be formed as a result of a reaction between a source of chlorine (for example, chlorinated water or salt) in the food or a food contact material and a lipid source. This reaction is encouraged during the heat processing of foods, including the roasting of cereals and malts used for brewing. It is also known to occur in acid-hydrolysed vegetable protein (HVP) when produced using hydrochloric acid.
Scientists have observed similar occurrences in foods and food ingredients at low levels as a result of processing, migration from packaging materials during storage, or in domestic cooking. Once formed, scientists claim that the stability of 3-MCPD might depend on the pH and temperature to which it has been exposed. The higher the pH and the higher the temperature of the heat treatment, the greater the rate of degradation of 3-MCPD.
In the brewing industry, malt extracts are widely used for imparting colour and flavour to beer and levels of 3-MCPD up to 200mcg/kg have been found in roasted products, reports the IFST. Fermented sausages such as salami and some heat processed foods have also been found to contain low levels of the contaminant.
3-MCPD can also occur in foods which have been in contact with materials containing epichlorohydrin-based wet-strength resins - used in the production of some tea bags and sausage casings.
A project, commissioned by the UK Food Standards Agency in 1998, analysed 300 food samples in retail packs. The survey identified baked goods, bread and cooked/cured meat and fish as other food groups most likely to contain 3-MCPD.