Toxins aflatoxins

In some cases, species differences in toxicity are due to more than one metabolic difference. For example, research on the fungal toxin aflatoxin B1 indicates that humans are particularly susceptible, more so than rodents, with rats being more susceptible than mice. Interestingly, cynomologous monkeys are also relatively insensitive probably due to the lack of constitutive CYP1A2. 

How the natural toxin aflatoxin, produced by a fungus, damages DNA. The aflatoxin is converted into a reactive produa in the liver that interacts with components of DNA (the bases A, T, C, G). This changes the base code, leading to mutations and cancer. 

Allcroft, R., and Carnaghan, R. B. A. (1962). Groundnut toxicity Aspergillus flavus toxin (aflatoxin) in animal products. Vet. Rec. 74, 863-864. 

Overall, about 400 toxins have been identified, which are certainly but a small proportion of what is actually found in nature. Out of this remarkable inventory, several are reckoned as typical bioterrorism agents. Presented here are few prominent toxins two protein toxins (botulinum and SEE)—hence detectible and treatable by anti-toxins—and three non-protein toxins (T-2 toxin, aflatoxin and aconitine), hence hardly detectable or treatable by antidotes. Etiological diagnosis of toxins is often extremely complicated. 

The fungal toxin aflatoxin, which generates terrible diseases, but only on the long term (was apparently destined to be used against the Kurds in Iraq). 

When aflatoxin was fed to animals, certain related toxins, aflatoxin Mi (30) and Mj (32), were isolated from the milk [267]. These toxins have also been detected among the metabolic products of Aspergillus flavus [268]. 

Purity control limits contamination with pathogenic bacteria Staphylococcus aureus, Escherichia coli. Salmonella-species, Pseudomonas aeruginosa, Clostridium-species and others), yeasts, moulds, microbial toxins (aflatoxins, endotoxins), toxic heavy metals (lead, cadmium, mercury, arsenic e.g. from industrial emission), pesticide and herbicide residues, fumigants (ethylene oxide, methyl bromide, phosphine) and radionuclides. Furthermore, impurities with other plants parts ( foreign organic matter ) are limited. Moist levels must be below a certain maximum to avoid deterioration by microorganisms. Excreta of animals and dead insects must be absent. The ash value and acid-insoluble ash limits the amount of inorganic impurities (soil, sand). 

Veterinary drugs and fattening aids, e. g. penicillin in milk, natural or synthetic estrogens in meat Toxins (aflatoxins, enterotoxins, ochratoxins) in food... 

Iraq succeeded in producing the biological pathogens and toxins aflatoxin (a mycotoxin), anthrax, botulinum toxin (BTX),... 

The number of clear human epidemiologic studies is small. A total of approximately 50 compounds (c.g., benzene, vinyl chloride) and complex e.xposures (e.g., aluminum production, tobacco smoke) have sufficient data available to permit their classification as human carcinogens. The most potent human carcinogens known, the aflatoxins. are of natural origin. Their presence in food products through infestation by toxin-producing fungi constitute a serious problem in several tropical and subtropical countries. 

Sophisticated and veiy sensitive methods have been developed in the food industry for detecting many other microbial toxins. For example, aflatoxin deteetion in seedstuffs and their oils is performed by solvent extraction, adsorption onto columns containing selective antibodies for them, and detected by exposure to ultraviolet light. 

Assessment of whether a chemical has the potential to cause adverse effects in humans arises usually from direct observation of an effect in animals or humans, such as the acute poisoning episodes that have occurred when potatoes contain high levels of glycoalkaloids. Epidemiological studies have also been used to infer a possible relationship between intake of a particular type of food, or constituent of that food, and the potential to cause an adverse effect. Such observations led to the characterisation of the aflatoxins as human carcinogens. However, natural toxic substances that occur in plant foods have often been identified through observations in animals, particularly farm animals. It was observations of adverse effects in farm animals that led to the further characterisation of the phytoestrogens and the mycotoxins. In other instances, the concern arises from the chemical similarity to other known toxins. 

More data are needed on post-harvest storage diseases of organic crops, because chemical controls cannot be used on organic products. This is important in relation to fungal toxins, e.g. aflatoxin. 

Deoxynivalenol Nivalenol Zearalenone T-2 toxin Moniliformin Ochratoxin A Aflatoxins... 

Walker SJ, Llewellyn GC, Lillehoj EB, Dashek WV. Uptake and distribution of aflatoxin Bj in excised, soybean roots and toxin effects on root elongation. JEnviron ExperBot 1984 24 113-122. 

Contamination of the world s crops by aflatoxin is estimated to cost 10 billion annually, due not only to the direct loss of crops and animals, but also to the maintenance of toxin monitoring services and the indirect cost of human and animal health care (Trail et ah, 1995). Strict legislation will protect the public health in developed countries however, many countries do not have such legislation or testing capacity. Even if such legislation and testing could be implemented, they would reduce the health risk but could not eliminate large-scale economic losses similar to those currently faced by the U.S., the European Union, and other developed countries. 

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