Aflatoxins materials

Where specific Regulations are in force then the methods associated with the Regulations shall be accredited if the control laboratory wishes to offer enforcement of the Regulations to customers. Examples of these are methods of analysis for aflatoxins and methods of analysis for specific and overall migration for food contact materials. 

The determination of trace components (halogens, heavy metals, pesticides, aflatoxins, and restsolvents) in flavor and fragrance materials used in foods and cosmetics is becoming increasingly important. 

Enzyme-linked immunosorbent assay (ELISA) is a very useful technique for the specific and sensitive assay of certain compounds, in which suitable antibodies, monoclonal or polyclonal, to the compounds are available. The technique has found particular application m the monitoring of environmental contaminants and toxins, either studying the primarily contaminated materials, e.g., foodstuffs, or body fluids of potentially exposed humans. The technique has been increasingly applied to monitoring the carcinogenic mycotoxins, the aflatoxins. 

There has been limited use of high temperature exposure for destruction of the aflatoxins in various nuts and coffee beans but this has been offset by the deteriorative changes in the raw material. 

For aflatoxins, an ML of 15 /xg/kg for total aflatoxins in peanuts intended for further processing was agreed by the 23rd CAC in 1999, as well as a draft sampling plan, on an interim basis, to be further developed by the CCFAC and the CCMAS. A proposal for an ML for aflatoxin Mi in milk is also in the pipeline, whereas a Codex Code of Practice for the reduction of aflatoxins in raw materials and supplementary feedstuffs for milk-producing animals was adopted by the CAC in 1997. 

The majority of toxicants in foods are contaminants, (e.g., microbial toxins, pesticide residues, leachable chemicals from packaging materials, food coatings, traces of heavy metals). However, the major issue in food safety is the contamination of food by mycotoxins in items such as milk and milk products, meat and meat products, and peanuts (groundnuts). Aflatoxin is highly toxic and lethal, and its carcinogenic potential is well established, even at doses as low as 0.05. ig. Mycotoxins also infect food products like rice, pulses, tapioca, and betelnuts. (Table 10-2). 

Aflatoxins, for example, Bj (36) and their biological markers have been determined using ESI (90,91). Aflatoxins B1 B2, G1 G2 were analyzed in food samples by LC/ESI/MS using a 150 x 2-mm C18 column eluted isocratically with acetonitrile-MeOH-10 mM NH4OAc (2 16 15) (90). The positive ESI spectra were dominated by the protonated molecules, which were used for SIM. The method enabled concentrations down to lppb to be detected in various food materials. LC/ESI/MS/MS has been used for the detection of aflatoxin DNA adducts as urinary biomarkers of exposure (91). 

A specific mutation in the genetic material has been detected in people exposed to aflatoxin. An important factor in determining susceptibility may be individual variation in the metabolism of aflatoxin. A significant risk factor in liver cancer is infection by the virus that causes hepatitis B, and it appears that a combination of aflatoxin exposure and the viral infection makes individuals especially susceptible. 

For a food contact material with no relevant genotoxicity or carcinogenicity data with an estimated daily intake (EDI) of < 1.5 pg/p/d, FDA would not normally recommend testing. If the food contact material contained SAs, such as the bisfuran polycyclic substructure of aflatoxin Bj (CASRN 1162-65-8), FDA may recommend additional specific tests due to the potential concern for public safety. 

More recently, certain non-natural, exogenous contaminants in fats and vegetable oils have become an issue (43). Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dioxins, and aflatoxin, to name the more serious offenders, can hnd their way into fats and oils by a variety of pathways. In the case of PAHs, direct drying of seed materials (44, 45) is a major pathway. Dioxins, released to the environment as unintentional byproducts of combustion processes, are mainly found in animal and hsh fats as a result of ingestion of dioxin-contaminated feeds, soils, and sediments (46) by these animals. PCBs were used as dielectric fluids in electrical equipment and as flame-retardants until their production was banned (USA—1977 Europe—1985) they are generally not found in edible oils. 

Contamination with micro-organisms When 62 samples of medicinal plant material and 11 samples of herbal tea were examined in Croatia, fungal contamination was found to be abundant (159). Aspergillus flavus, a known producer of aflatoxins was present in 11 and one sample respectively. Mycotoxins were found in seven of the samples analysed. 

Toxicity is the property or properties of a material that produces a harmful effect upon a biological system. A toxicant is the material that produces this biological effect. The majority of the chemicals discussed in this text are of man-made or anthropogenic origin. This is not to deny that extremely toxic materials are produced by biological systems venom, botulinum endotoxin, and some of the fungal aflatoxins are extremely potent materials. However, compounds that are derived from natural sources are produced in low amounts. Anthropogenically derived compounds can be produced in millions of pounds per year. 

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