First portable low-cost device developed for rapid detection of aflatoxins
July 29, 2016
A new technology that detects aflatoxins on location, can save lives and open export markets for African and Asian countries. The rapid test kit device is also affordable at under US$ 2. This exciting advancement combined with a mobile extraction kit that will be ready in two months, will be the first portable cost-effective way for farmers and others to detect aflatoxins instantly. Currently, the test can be applied to detect aflatoxin in groundnuts.
The test kit launched officially on July 26 by Dr Allan Chilimba, Deputy Director, Department of Agricultural Research Services (DARS), Lilongwe at ICRISAT-Malawi, requires limited technical knowledge or training and can be done on location by farmers, agro-dealers and food processors. For example it can be used by traders to check for contamination before concluding a sale. The rapid detection is useful for public health authorities to help identify suspected samples in cases of an outbreak of aflatoxin poisoning.
The new test is simple to perform and can detect contamination at levels of 10 parts per billion (ppb) in less than 15 minutes. While the competitive Enzyme-Linked Immunosorbent Assay (cELISA) test, developed in 2000 by ICRISAT, which has to be done in a laboratory by trained technicians, and other analytical tests can take up to two days.
The compact portable device is based on the lateral flow immunoassay test (popularly known as the strip test like that used to detect glucose in human blood). If aflatoxin is present in the sample, then one pink line appears on the strip, whereas if the sample doesn’t have any aflatoxin, two pink lines will appear.
“The device will contribute to manage and reduce the entry of aflatoxins in the food value chains, improve diagnosis for local and export trade and support the food processing industry to maintain low exposure levels in food products in our local markets as well as for export markets,” said Dr Anitha Seetha, Scientist, ICRISAT, Malawi.
Aflatoxin is carcinogenic. The Food and Agriculture Organization (FAO) estimates that 25% of all crops in the world are affected by aflatoxins. The WHO recently estimated that in 2010 around 20,000 people died globally from aflatoxin poisoning and an equal number fell ill.
Groundnut, maize, sorghum, pearl millet, chilies, pistachios, cassava and other food products are contaminated by aflatoxin each year. They not only affect human and livestock health but can also affect the marketability of food products. Many countries reject imports of agricultural products that exceed certain levels of aflatoxin, costing farmers millions of dollars every year.
“ICRISAT has been working with smallholder farmers in Africa to combat the aflatoxin problem. This kit will enable rapid and cost-effective deployment by the government and private sector to protect public health and also improve the export prospects for African countries,” said Dr David Bergvinson, Director General, ICRISAT.
Around 90 countries have regulations that establish maximum aflatoxin limits in food and feed products. The limits range from 4 ppb in the EU to 15 ppb in the USA.
Aflatoxin contaminated food can pose a serious health risk. Symptoms of aflatoxin poisoning include: liver cancer, fluid retention, increased incidence of Hepatitis B infection, and stunting in children. In poultry and livestock, aflatoxin can cause feed refusal, loss of weight, reduced egg production and contamination of milk. Tropical countries are primarily affected, which includes the majority of Africa, India and other south Asian countries.
The development of the sample extraction kit is currently underway and will be ready in two months so that the whole process can be carried out in the field or anywhere else. The kit has been developed by Dr Anitha Seetha.
Aflatoxin is a toxic substance produced by mold fungi (Aspergillus flavus and A. parasiticus) that can grow on poorly managed agricultural crops, particularly groundnuts.
If eaten in sufficient quantities, aflatoxin can cause serious sicknesses that can lead to liver and several other cancers.
Groundnuts for sale and export should be free from aflatoxin.
Therefore appropriate crop management is essential at pre- and post-harvest times.
Effects of aflatoxin
Aflatoxin is carcinogenic and can cause liver and other cancers in humans.
It is synergistic with hepatitis viruses B and C.
It lowers the body’s normal immune response to invasion by foreign substances.
It impairs growth in children, notably in Africa, and causes childhood cirrhosis in India.
In poultry and livestock, aflatoxin can cause feed refusal, loss of weight, reduced egg production, and contamination of milk.
Species
