Eating Spoilt Foods Can Cause Liver Cancer — Expert

A food microbiologist at the Federal Polytechnic, Idah Kogi State, Dr. Michael Ukwuru, has warned Nigerians against consuming spoilt tomatoes, black-stained onions and poorly preserved grains.

According to Ukwuru, the practice could expose people to cancer-causing toxins.

His warning follows reports of increased demands for spoilt tomatoes by Nigerians due to economic hardship and surge in the cost of tomatoes in markets. His warning also aligned with that of the Lagos State Consumer Protection Agency (LSCPA), and a health influencer, Chinonso Egemba, popularly known as Aproko Doctor, who recently urged members of the public to desist from consuming spoilt tomatoes.

A few months ago, concerns were raised over tomato infestations in Kano State, one of Nigeria’s major tomato-producing hubs, where pest attacks destroyed several farms and triggered fears of nationwide shortages and rising prices.

Findings by THE WHISTLER at Orange Market in Mararaba, Nasarawa State, revealed that tomato prices surged by over 400 per cent within one week, worsening pressure on traders and consumers already battling economic hardship

Traders attributed the increase to seasonal scarcity, rising transportation costs, fuel prices, and recent pest attacks affecting tomato-producing states.

The food microbiologist who spoke to THE WHISTLER, urged the public to prioritise their health despite the reasons behind the high demand for spoilt tomatoes.

He explained that fungi growing on spoilt foods produce aflatoxins and other harmful mycotoxins capable of causing liver cancer and other serious health complications.

“Talking about mold infestation of tomato and onion, it is very true that consuming them could lead to liver cancer. The black stains often seen on onions and the whitish molds found on spoilt tomatoes are signs of fungal contamination caused largely by poor storage conditions.

“These molds produce aflatoxins, and apart from aflatoxins, there are other toxins produced by molds, but these aflatoxins can be very dangerous to health when consumed along with food. Most of them can survive the temperature of the cooking, get consumed and go into the blood stream,” he stated.

He further warned that washing or cooking affected onions or tomatoes does not remove the danger because the fungi penetrate deep into the food.

“When molds stay on the surface, they produce hyphae. These hyphae are collectively called mycelium, they penetrate into the onion releasing the toxins inside the onion,” he explained.

Ukwuru added that cutting away visibly affected portions does not address the problem, as some mycotoxins are heat-stable and can survive normal cooking temperatures.

“The heat required to cook your food cannot destroy the toxins. After cooking, the toxins remain potent,” he warned.

Speaking further, he said moist and poorly ventilated storage environments encourage mold growth on onions, tomatoes and several staple foods including maize, rice, millet, beans and groundnuts.

“If they are stored and the storage condition is not proper, definitely it will attract mold growth. And when it attracts mold growth, then it is likely to attract toxin production,” he said.

The microbiologist also warned against feeding mold-infested grains to animals, stressing that toxins could be transferred to humans through meat and dairy consumption.

“Animals infested with these toxins could be killed for consumption, and human beings that consume the meat of these animals can also have these toxins transferred onto them because they are heat stable and could not be destroyed by heat,” he added.

Ukwuru urged consumers to store food crops in dry and properly ventilated places, while avoiding plastic bags that trap moisture. He also called on food regulatory and consumer protection agencies to intensify monitoring of open markets and sanction traders selling contaminated food items.

He said awareness on proper food preservation remains critical in reducing health risks associated with mold-infested foods.