Environmental & food processing contaminants

Environmental contaminants are chemicals present in the environment that have a known or potential impact on human health. They may be present in food and water supplies. Processing contaminants are generated during the processing cycle of a product. They are formed when a chemical reaction takes place between the food and processing (e.g., disinfection, fermentation, heating, canning, or grilling). Examples of these contaminants include Acrylamide, PAH and Melamine.

Dioxins are a group of chemically-related compounds that are persistent environmental pollutants (POPs). The chemical name for dioxin is: 2,3,7,8- tetrachlorodibenzo para dioxin (TCDD). Dioxins are of concern because of their highly toxic potential. Experiments have shown they affect a number of organs and systems. Many countries monitor their food supply for dioxins. This has led to early detection of contamination and has often prevented impact on a larger scale. In many instances dioxin contamination is introduced via contaminated animal feed, e.g. incidences of increased dioxin levels in milk or animal feed were traced back to clay, fat or citrus pulp pellets used in the production of the animal feed.

The quantitative chemical analysis of dioxins requires sophisticated methods that are available only in a limited number of laboratories around the world. Increasingly, antibody-based screening methods are being developed, and the use of such methods for food and feed samples is increasingly being validated. Such screening methods allow more analyses at a lower cost, and in case of a positive screening test, confirmation of results must be carried out by more complex chemical analysis.

Acrylamide is a chemical that naturally forms in starchy foods during high-temperature cooking, including frying, baking, roasting and also industrial processing, at +120°C and low moisture. Acrylamide has been detected in a range of foods including fried or roasted potato products, cereal-based products (including sweet biscuits and toasted bread) and coffee.

Acrylamide (AA, 2-propenamide, C3H5NO (71.09 g/mol , CAS No. 79-06-1)) is a colorless and odorless crystalline. It dissolves in water, alcohol, and other polar solvents, but tends to be hydrolyzed into acrylic acid in an acidic and alkali environment. Increasing research on AA in foods has been investigated in the past thirty years, involving toxicity, formation, mitigation, and detection.

Melamine is a synthetic chemical used in the manufacture of resins, pigments, and superplasticisers. A human can be exposed to melamine through various sources such as migration from related products into foods, pesticide contamination, and illegal addition to foods. Toxicity studies suggest that prolonged consumption of melamine could lead to the formation of kidney stones or even death. Therefore, reliable and accurate detection methods are essential to prevent human exposure to melamine. Some methods for the detection of melamine include instrumental analysis, immunoassays, and sensor methods.