Another GM 'solution' to a problem produced by intensive farming (16/10/2004)
- Details
1.Mycotoxins data
2.Icrisat tackles mycotoxins
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1.Mycotoxins
http://www.foodmarketexchange.com/datacenter/product/organic/details/dc_pi_organic_03.htm
Mycotoxins are toxic by-products of Aspergillus molds that can grow on a wide variety of foods and animal feed. When eaten by dairy cattle, some of these toxins can be metabolized and their metabolites transferred into milk. Aflatoxins are the most toxic of these compounds and can induce liver cancer in humans at very low concentrations if ingested over a long time.
Although fungicides are not allowed in organic farming, many studies have shown that organic farming does not increase the risk of mycotoxin contamination.[28] In fact, three studies have found that aflatoxin M1 levels in organic milk are lower than in conventional milk.[29], [30] A study by the FSA showed that whereas 3 percent of conventionally-produced milk samples contained aflatoxin M1, no samples of organic milk were contaminated.[30]
As organically raised livestock are fed greater proportions of hay, grass and silage, rather than corn, there is reduced opportunity for mycotoxin-contaminated feed to lead to contaminated milk. Good practices in animal feeding also mean that ingredients are checked to ensure quality standards are maintained and that feed is stored in such a way as to avoid contamination.
References
[28] Woese, K. et al. (1997). A comparison of organically and conventionally grown foods - results of a review of the relevant literature. J Sci Food Agric. 74; 281-293.
[29] Woese, K., Lange, D. Boess, C. and Bogl, K.W. (1997). A comparison of organically and conventionally grown foods - results of a review of the relevant literature. J. Sci. Food Agric. 74; 281-293.
[30] UK Food Standards Agency (2001). Survey of Milk for Mycotoxins (Number 17/01).
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2.Icrisat to set up global aflatoxin test centres
BV MAHALAKSHMI & ASHOK B SHARMA
Financial Express, October 14, 2004
http://www.financialexpress.com/fe_full_story.php?content_id=71355
HYDERABAD: Following its development of a cost-effective commercial kit for estimation of mycotoxins, the International Crops Research Institute for the Semi-Arid Tropics (Icrisat) is planning to set up testing centres across the globe that can act as one-stop-shops for testing practices to check for aflatoxins. Currently, the testing centres are available in East and West Africa besides Hyderabad and the institute is planning to increase the number of such centres across the globe.
The institute is also working on two anti-fungal genes, Chitinease, a gene isolated from rice and Gluconase from maize, which can control production of toxins. However, the tests are still in the control lab conditions. Further, it has also advised agronomic control to reduce aflatoxins at farm level by use of calcium, cereal crop residues and bio-control agents like Trichoderma and bacteria in the compost. These agronomic controls reduce the levels of aflatoxins to a considerable extent.
Mycotoxins are chemical substances produced by fungi that contaminate crops either during the cropping season or in storage, says principal scientist, Icrisat, Dr Farid Waliyar. In order to develop cost-effective and simple technologies, the UK’s department of international development (DFID) is funding the research institute for developing Enzyme-linked Immunosorbant Assay (ELISA) methods to determine the aflatoxin levels. The aflatoxins, which thrive on many agricultural commodities, is carcinogenic and lowers the body’s normal immune response to invasion by chemical substances, he said.
“This is part of our integrated approach to develop inexpensive methods to determine the levels of aflatoxins and help the poor farmers and also improve their health,” he said.
As part of its research progress, the institute has identified two genes which are responsible for causing the toxins. These genes have been isolated from species of Aspergillus, a fungus, which causes significant loss to human beings and livestock as well. The ELISA tests will quantify the presence of an antigen in a sample using an enzyme-labelled toxin and antibodies specific to aflatoxins. The tests can be done for as low as Rs 35 for testing, compared to the price at the National Institute of Nutrition (NIN)’s rate of Rs 1,000 per sample. About 80 samples can be tested and reported in a week’s time unlike 20 days elsewhere.
On the importance of these, testing practices, Dr Waliyar informed that worldwide, substantial grains have been affected each year. When the cattle consume aflatoxin-contaminated food, they produce contaminated milk. The legal limit in milk is 0.05 ppb (parts per billion) for aflatoxin. “The effects of aflatoxins on crops can occur at all levels of crop production as there are no high levels of resistance and no 100% control measures,” he opined. It is also learnt that many containers of chillies being exported to the European Union (EU) countries were rejected during the previous seasons because of higher levels of aflatoxin content in them. With the European Commission proposing maximum limits for aflatoxins with standards ranging from 4 ppb in cereals, edible nuts and dried fruits to 10 ppb for nuts that are subject to further processing, exports with reduced ppb levels becomes one among the other stringent factors due to poor adoption of post-harvest technologies. Perhaps, these test practices can go a long way to help in reaping the right harvest.