Pollutants in food

Reilly, C. Pollutants in food - metals and metalloids. In Szefer, P., Nriagu, J.Q. (eds.) Mineral Components in Foods, pp. 363-388. CRC Press/Taylor Francis Group, London/New York (2007)... 

It is however a very difficult task that I am supposed to fulfill in half an hour. We enter indeed into a very wide and controversial subject the toxicity of small concentrations of chemical substances, commonly called the pollutants (in food, air, water, wastes, fertilizers, working places, etc—), a field where the amount of really relevant knowledge is not yet very extensive. 

Fast and Selective Analytical Procedures for Determination of Persistent Organic Pollutants in Food and Feed Using Recent Extraction... 

Information on the presence of pollutants in foods is available through the U.S. Food and Drug Administration s Food Information Storage and Retrieval System and numerous FDA publications that give dietary levels or levels in particular foods of a number of pollutants. 

Some minerals are found naturally in foods in variable amounts and can be modified, or others can be added, during industrial processing of food. Table 1 indicates the amounts of some of the macro- and microelements that can be found in various raw and processed foods. Moreover, almost all these minerals can be found as pollutants in foods due to environmental or industrial factors, and are analyzed for hygienic reasons, and not as natural components of foods. 

Checking for pollutants in foods and feeds Many different pollutants such as agrochemicals, mutagens, heavy metals, antibiotics, and growth-stimulating hormones are detectable by biosensors [186]. 

Pollutants of this type are found to be present in many sampled soils, streams, ground and waste waters. One of the most important preventive measures in this case is to rapidly determine the source of the pollutant and magnitude of the threat using on-site measurements. Analysis of low levels of OPC pollutants in foods is another potential application of the sensor. 

Polycychc aromatic hydrocarbons (PAHs) are carcinogens produced by the thermal breakdown of organic materials. These are widely distributed in both food and the environment, and are some of the principal carcinogens in cigarette tar and air pollution. Of over 20 PAHs isolated, benzopyrene and quinoline compounds are the most commonly encountered in foods, particularly those which are broiled or fried (111). Shellfish living in petroleum contaminated waters may also contain PAHs (112). 

Frank R, Smith EH, Braun HE, et al. 1975. Organochlorine insecticides and industrial pollutants in the milk supply of the southern region of Ontario, Canada. J Milk Food Technol 38 65-72. 

Both PCDDs and PCDEs are refractory lipophilic pollutants formed by the interaction of chlorophenols. They enter the environment as a consequence of their presence as impurities in pesticides, following certain industrial accidents, in effluents from pulp mills, and because of the incomplete combustion of PCB residues in furnaces. Although present at very low levels in the environment, some of them (e.g., 2,3,7,8-TCDD) are highly toxic and undergo biomagnification in food chains. 

Although SPME was applied initially for the analysis of relatively volatile environmental pollutants in waters, rapid developments have enabled SPME to be successfully applied for the analysis of pesticides in water, wine and more complex food samples such as honey, fruit juice and pears, vegetables and strawberries. With food samples, most analysts recognize the need for some sample pretreatment in order to minimize matrix effects. The matrix can affect the SPME efficiency, resulting in a reduced recovery of pesticides. The most common method is simply to dilute the sample or sample extract with water. Simpltcio and Boas comminuted pears in water prior to the determination of pesticides. Volante et al. extracted over 100 pesticides... 

Organic carboxylic acids are commonly found in foods, in the adipate process stream, and as pollutants. Fatty acids are the lipophilic portion of glycerides and a major component of the cell membrane. Phenols are widely used in polymers, as wood preservatives, and as disinfectants. Chloro-phenols such as 4-chlorophenol, two isomeric dichlorophenols, 2,4,6-tri-chlorophenol, three isomeric tetrachlorophenols, and pentachlorophenol were separated on a Dowex (The Dow Chemical Co. Midland, MI) 2-X8 anion exchange resin using an acetic acid-methanol gradient.138... 

Yoshimitsu Hirao and C. C. Patterson. Lead Aerosol Pollution in the High Sierra Overrides Natural Mechanisms Which Exclude Lead from a Food Chain. Science. 184 (May 31, 1974) 989-992. 

Due to the higher amounts of organic pollutants in the food industry wastewater, conventional biological treatment systems can be used. 

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