Uganda running out of safe food options

The biggest threat is posed by locally grown items such as maize, groundnuts and cassava, from which maize flour, cassava flour and groundnuts’ paste are processed. Most of these are believed to be contaminated with cancer-causing particles and mould brought on by poor post-harvest management.

While presenting a paper titled Building a food safety system in Uganda at the second global forum of food safety regulators organised by the Food and Agriculture Organisation (FAO) and the World Food Programme (WFP), in Thailand in October 2004, the then Director General of Health Services at the Ministry of Health, Prof Francis Omaswa, talked up the need for strengthening laws around food processing and hygiene.

“Much of the burden of illness results from basic sanitation failures that occur in food production, processing, storage, transportation, retailing, and handling in the home. Achieving basic food hygiene is made difficult by the lack of necessary sanitation infrastructure in many areas of the country and in food processing industries,” he told the conference.

Not much has since changed.

Grains

The threat posed by the consumption of maize flour, beans, cassava flour, millet flour, and groundnuts principally traces its roots to contamination from aflatoxins. The World Health Organisation (WHO) warned in the food and safety digest of February 2018 that aflatoxins contamination “poses a serious health threat to humans and livestock.”

Mr Joseph Ssemujju, an oncology nutritionist attached to the Uganda Cancer Institute in Mulago, said consumption of aflatoxin-contaminated food is associated with cancer of the liver and cancers of the gastrointestinal tract.

The good news is that some of the processes of turning, say, maize into flour can eliminate the dangers posed by aflatoxins. Prof Archileo Kaaya from Makerere University’s Department of Food Technology and Human Nutrition, however, says that this is dependent upon the mode of processing.

“If you remove part of the germ and the bran, some of the aflatoxins will stay. If you remove all the bran and all the germ, chances are that there will be very little or no aflatoxins, but if you remove the whole grain, then they will all be there in that flour,” says Prof Kaaya.

The bad news is that aflatoxins will not be eliminated by cooking or roasting.

“They do not have a life. You cannot kill a chemical. When the moulds enter into the maize, they produce chemicals just like you produce urine and faeces, they also do the same. When you cook or roast, you kill the moulds, but not the chemicals that they will have produced. You do not affect them when you cook,” Prof Kaaya says.

Whereas chances are high that the dangers like aflatoxins posed in crops can be snuffed out through the process of conversion of the grain into crop, there are no chances of doing so during the processing of cassava flour, millet flour or groundnut paste.

Double threat

Unlike maize where the removal of parts of the seed coat, the endosperm and embryo reduce the chances that the flour will have aflatoxins, there is no escape when it comes to the processing of crops like cassava and millet into flour.

It gets even more complicated when it comes to conversion of sim-sim and groundnuts into paste. The kind of machines locally used to process the two introduce a threat of a different nature.

“The machines that are used are not food grade. They are not stainless steel. They are mild steel, which wears and tears so the particles end up into the flour and the paste. So we take a magnet and pass it in the flour or the paste. You will see a lot of machines particles attaching themselves to the magnet,” Prof Kaaya says.

Mr Ssemujju says the scenario leaves consumers exposed to the double risk of cancer from aflatoxins and possible destruction of the intestinal wall on account of consumption of metallic objects.

“When this food is consumed, some of these metals stick along the alimentary canal. Sometimes these metals may not move away. The metals settle in that layer for some time and eventually damage it. Since the cells are damaged, it probably gives the chance of cancer of the intestines,” Mr Ssemujju says.

Ms Sylvia Kirabo, the spokesperson of Uganda National Bureau of Standards (UNBS) , concedes that not all the food products on the market are safe, but hastens to add that it is not UNBS to blame for food processing plants that are not made of food grade material.

“The only food that UNBS can attest to is the one that has been certified. If it is well labelled and has a quality mark, then we can say it is safe and has no contaminants. As for the jua kalis, it is the public health monitoring and public health inspectors who are directly recruited by the Ministry of Health and deployed in all local governments. Those are the ones meant to regulate the jua kalis,” Ms Kirabo says.

Aflatoxins in beef, milk

According to Business Queensland, an electronic publication of the State of Queensland, Australia, up to five percent of aflatoxins consumed by lactating animals end up in their milk. Similarly, feeding beef cattle on aflatoxin contaminated feeds means that the aflatoxins will end up in beef and other beef products like sausages.

Aflatoxins in eggs, chicken

It also follows that feedng poultry on aflatoxin contaminated feeds means that aflatoxin poisoning will occur in eggs and the chicken or turkey that ends up on our plates.

Pork

Aflatoxin poisoning is also known to occur in pigs, which means pork and pork products like bacon and sausages might also not be as safe as most people may want to believe.

Arsenic rice

A report of a study carried out by Makerere University’s Department of Medical Physiology, to show the modifying effect of boiling, soaking and washing rice prior to its preparation, revealed that the arsenic levels in eight varieties on the market are much higher than those recommended by the WHO.

WHO puts the acceptable limits for arsenic in food at 0.01ppm and in waters 10ppb. Ppm or ppb are used when measuring very small amounts. Arsenic is a naturally occurring, semi metallic element in both organic and inorganic compounds that is widely distributed in the earth’s system. Inorganic arsenic compounds are, however, believed to be more toxic than the organic ones.

According to information on the website of the National Institute of Environmental Health Sciences (NIEHS), exposure to arsenic over a prolonged period of time might affect the cardiovascular, endocrine, immune and respiratory systems.

It is also known to affect the prostate gland, the nervous system, the kidneys, liver and bladder.

Local rice

According to the report of the study which was published in the Journal of Food Safety and Hygiene earlier this year, locally grown varieties of rice contain even more arsenic than the imported ones.

“From the results, we detected that the local rice brands such as C (grown in the Lwera wetland near Masaka City) and F (grown in the Bugiri District) had slightly higher levels of arsenic than all the other brands in the market,” the report reads in part.

C brand rice had 0.0132ppm of arsenic, while F had 0.0702ppm of arsenic.

Though the other six varieties of rice, both local and imported, were found to have been less contaminated, they contained more arsenic than what WHO recommends.

Water

The same report indicates that tap water, both boiled and unboiled, used in the different tests was also highly contaminated. Levels of arsenic in the said water ranged between 0.001ppm and 0.003ppm. The majority of water samples had contamination levels of up to 0.0002ppm.

Vegetables

Only last March, researchers from Makerere University’s Department of Food Technology, and the Department of Geology and Petroleum Studies laboratories, released findings from a research conducted between March and December 2021. The results revealed that milk, vegetables, and fruits from farms in the greater Kampala Metropolitan area were heavily contaminated with cancer-causing agents.

“The concentrations of [metals such as] iron, cadmium, chromium, lead and nickel in all sites were higher compared to [WHO] limits for heavy metals in vegetables and fruits,” the report reads in part. Some of the crops that were analysed included yams, pumpkins, pawpaws, amaranthus (dodo), bitter berries (Katunkuma), and pasture grasses for animals.

The study concluded that the different crop varieties absorb toxic metals that are eventually ingested by humans resulting in different ailments. Is there a way around the problem?

Mr Moses Echwodu, whose UCCF encourages the cultivation and consumption of vegetables and fruits in schools for purposes of boosting immunity, does not think so.

“We have a lot of soil contamination that is going on across the country and you expect it to get worse because of industrialisation,” he says.

Preservatives

Prof Archileo Kaaya from Makerere University’s Department of Food Technology and Human Nutrition, says the matter of use of nonfood grade processors has been raised with UNBS for more than two decades now.

Mr Moses Echwodu, the chairman of the Uganda Child Cancer Foundation (UCCF), an organisation that provides support to child cancer patients and conducts cancer awareness campaigns in mostly schools, says a discussion around preservatives—much like that on aflatoxins—is due.

“I fully understand when you talk about aflatoxins, but we cannot go without mentioning the preservatives that are being used. What are the standardised measures for the preservatives that are in use? UNBS should be telling us,” Mr Echwodu said.

Ms Sylvia Kirabo, the spokesperson of UNBS, insists that the standards around preservatives are clear.

“General standards for food additives and preservatives are spelt out in Code US 45:2019. They were governed by the Codex Alimentarius Commission, which is under both the World Health Organisation (WHO) and the Food and Agriculture Organisation (FAO) of the United Nations (UN). They have been researched globally by food safety experts, manufacturers and health practitioners. They are periodically reviewed, the last time having been in 2019. It is, therefore, not true that we are not clear on that,” Ms Kirabo says.