Hope as Dar farmers apply biological weapon to thwart deadly fungi this season

TUESDAY January 28, 2020

By Joe Lihundi

Tranquility News Reporter, Arusha

Tanzania will soon begin to produce a biological control weapon against yellowish-green moulds (Aspergillus flavus) that cause aflatoxins — poisonous chemical posing a serious threat to human, livestock and trade.

Plans to build a plant in Arusha for mass scale production of a newly discovered prototype of the weapon against the soft growth that develops on old foodstuff store in warm, wet air are afoot, The East African has learnt.

A to Z Textile Mills Marketing Manager Julius Nyabicha confirmed that the firm is investing in  the plant and that production of AflasafeTZ01 is expected to begin before the end of January 2020 ready for application in maize and groundnut fields during the current cropping season.

Nyabicha said $1.5 million would be invested in the modular plant with the current capacity of producing 2,000 tonnes of AflasafeTZ01 a year.

“Going by our market projection, we’ll start with producing 100 tonnes this year and increase as the demand rises,” he said.

The AflasafeTZ01 will be sold at TSh16, 000 (over $7) per 4 kilograms which a one-acre farm needs a season.

The plant will be creating at least 30 direct jobs each year, let alone many other employment opportunities to be created in the value chain, Nyabicha said.

Long-term exposure to poisonous aflatoxins into the body enhances the potency to liver cancer as well as stunted growth, especially to children. It also compromises immunity and reduces production for livestock.

Aflatoxins are also known to be mutagenic toxins that can affect DNA (mutarogenic) and cause birth defects.

The once unsuspected A. flavus, as known among scientists, invade cereals like maize, oil seeds like groundnuts, tuber crops like cassava and livestock feeds to produce the aflatoxins.

The A. flavus comprise of L and S strains. All S strains are toxigenic, as they produce aflatoxins. On the other hand, there are some L strains that are toxigenic and others are atoxigenic — they do not produce aflatoxins at all.

The hardest part to farmers lies in identifying the crops that are contaminated by aflatoxins, as they are colourless, smell less and tasteless.

It is also difficult to differentiate between crops exposed to toxigenic or atoxigenic A. flavus, as all strains of the fungi bear a yellowish-green colour.

“The moulds explain the reason for death arising from consumption of high dose of aflatoxins (acute aflatoxicosis) to remain a chronic malady especially in rural areas where people are unable to afford variety of  nutritious foodstuffs,” Mr Jacob Njela, one of the researchers behind the bio control weapon, said.

Mr Njela said consumption of small amounts of aflatoxins for a prolonged period also led to liver cancer and stunted growth.

Thanks to the International Institute of Tropical Agriculture (IITA) latest findings that the aflatoxin causing fungus can actually be controlled through the use of AflasafeTZ01 on maize and groundnut farms two weeks before tasseling and flowering, respectively.

The supply of the AflasafeTZ01 will, however country specific owing to the fact that the strains of fungus used are acquired from Tanzania soils making it all natural.

IITA is a research institution and none profit organisation. Its role is to look for challenges facing the community and their solutions.

“For commercialisation of the Aflasafe TZ01, A to Z will produce and distribute to farmers after bidding among the competitors.

“IITA built capacity to A to Z staff to ensure they produce the product according to the needed standards,” Mr Njela explained.

The Research Associate with the project of bio control of aflatoxin at IITA-Tanzania chapter said aflatoxins contamination was a public concern not only in the country, but also all arround tropical countries.

“Hot temperature and high humid environments are to blame,” he said. Report shows that over 250 people died in Kenya due to acute aflatoxicosis in 2016.

The Kenya’s southern neighbour, Tanzania, was not an exception, as 19 out of 64 patients died of the same in Chemba, Kondoa and Kiteto at the centre of the country in the same year.

Many cases of patients and deaths occurred, but some were not reported. Records available at the Ocean Road Cancer Institute in Dar es Salaam show an increasing number of cancer patients.

Aflatoxins exposure may, in one way or another, be one of the causes, as they are grouped in grade number one among the causatives of cancer in the world.

Following aflatoxicosis outbreak in 2017 in Tanzania’s Central Zone, the FAO liaised with the IITA to expand in the aflasafe efficacy trials to affected districts.

The following year, the IITA, in collaboration with other players in the agricultural sector, conducted the efficacy trials in Chemba, Kondoa, Chamwino and Kiteto districts.

A baseline survey to ascertain the status of aflatoxins contamination in the country preceded the IITA research in 2012.

The baseline survey report showed about all the country was exposed to aflatoxins contamination above the recommended aflatoxins maximum limit level of 10 parts per bbillion (ppb) for total aflatoxins and 5 ppb for aflatoxins B1.

The report led the scientists to embark on the three-year efficacy trials research in Dodoma, Morogoro, Manyara and Mtwara which came up with the AflasafeTZ01.

The prototype has been specifically designed to compete with toxigenic fungi that contaminate maize and groundnuts at farm level throughout the country.

The two food crops were given priority because were highly susceptible to the fungi and widely consumed in so many African households.

Consumers of milk and milk products contaminated by aflatoxins also were exposed to effects caused by aflatoxins.

A breastfed baby is also at risk of being exposed if his mother consumed aflatoxins contaminated foods. Contaminated raw materials used for animal feed expose livestock and dairy products to aflatoxins.

Good raw materials can also be used and the contamination can occur during the processing, transportation and storage.

Food crops are contaminated with aflatoxins while in the farm before harvested and increase during transportation and storage if improper handling is practiced.

Pre-harvest pollution is mainly limited to maize and groundnuts while post-harvest poisoning is found in , rice, spices and a variety of other crops if improper handling is practiced, according to WHO.

Njela said the IITA was mulling over conducting another research on aflatoxins contamination in sorghum and sunflower following reports that the crops have also been contaminated. Sunflower is widely used for processing cooking oil in Tanzania.

AgroZ bags

Nyabicha said A to Z intends to reach out to all players in the grain production and supply chain in the aflatoxins bio control drive.

“We’ll also train transporters to handle foodstuffs carefully, including covering trucks during rain seasons to prevent grain from soaking excessive moisture,” he said.

Since warm and humid storage environment triggers levels of aflatoxins pollution more than in the field, A to Z started producing safe hermetic grain storage bags dubbed AgroZ Bags about six years ago.

“I’ve been using the bags for four years now; they effectively contain the storage challenge if one adheres to instructions,” maize trader Stephano Kingazi said.

Kingazi said the grain stored in the bags should be clean and adequately seasoned and that they should be tightly closed to prevent air from getting inside.

“If you mess up with these instructions, don’t blame the bags,” stressed Kingazi, adding that the bags should not be dragged or thrown down, lest they were perforated.

The bags, which are sold at between Sh4,000 ($1.8) and Sh5,000 ($2.2) each in the market, can be recycled for three seasons if one abides by the instructions.

They give a farmer or trader room to store grain as he waits for the price to appreciate in the market.

“I bought 20-litre tins laden with maize at Sh8,000 ($3.5) each and stored it in the bags, I am now selling the same crop at Sh20,000 ($8.8) a tin,” the trader said.

Kingaz said the bags saved the cost of buying cheap yet ineffective ones, applying poisonous pesticides on the grain and of hiring a labourer to clean and season the crop regularly.