Food is supposed to nourish the body, sustain livelihoods and support a healthy society. Yet, increasingly, concerns about unsafe food preservation and adulteration are raising difficult questions about what Nigerians eat, how food reaches our markets and what happens when the methods used to prolong its shelf life undermine its safety. The tragedy is that practices intended to preserve food and protect traders from financial losses may end up threatening public health, destroying consumer confidence and creating another source of food waste and environmental pollution.
Across Nigeria, concerns have been raised about the alleged use of dangerous chemicals to preserve fish, meat and grains, as well as to accelerate the ripening of fruits. Formalin, calcium carbide, agricultural insecticides and other substances have featured in warnings by regulatory agencies and reports on food safety. In January 2025, the National Orientation Agency raised concerns about the misuse of chemicals such as formalin, household bleach and insecticides in food handling. In November 2025, a Senate investigation reported findings concerning the use of calcium carbide for fruit ripening, insecticides for grain preservation and banned dyes in palm oil and pepper.
These concerns are serious because food safety is not merely a matter of taste, appearance or commercial value. It is fundamentally a public health issue. The food we consume must be safe from production to processing, transportation, storage and sale. When hazardous industrial or agricultural chemicals are introduced into food for purposes for which they were never approved, the consequences may extend far beyond the immediate transaction between a trader and a customer.
The problem is particularly troubling in a country where many households already struggle with the cost of food. For millions of Nigerians, the ability to buy fresh fish, meat, fruit and vegetables is influenced by daily income and changing market prices. Food is too valuable to be handled carelessly, yet it is equally too important to public health to be protected through unsafe chemical shortcuts.
One of the practices attracting attention is the use of calcium carbide to accelerate the ripening of fruits such as bananas, plantains and mangoes. Ripening is a natural biological process, but some traders may be tempted to speed it up to bring produce to market more quickly, achieve a more uniform appearance or reduce the time spent waiting for fruits to mature.
The attraction is understandable from a commercial perspective. Fruits that ripen faster can potentially be sold sooner, releasing working capital and reducing the risk of losses during transportation and storage. However, the use of calcium carbide for fruit ripening is prohibited in Nigeria because the substance may contain hazardous impurities, including arsenic and phosphorus compounds. Its reaction with moisture produces acetylene, which can accelerate ripening but is not equivalent to controlled food-grade ethylene ripening.
NAFDAC has repeatedly warned Nigerians about this practice. A 2024 study published in Discover Public Health, which examined fruit sellers and consumers in Ado-Ekiti, also found that knowledge of the health risks associated with calcium carbide was inadequate among many respondents. Ninety per cent of the 20 fruit sellers surveyed were classified as having poor knowledge of the associated risks. Although the study was limited to a particular location and a relatively small number of sellers, it illustrates why education and enforcement must work together.
The health concerns surrounding dangerous food chemicals depend on the substance, the amount, the route and duration of exposure, and the characteristics of the person exposed. Calcium carbide may contain hazardous contaminants, while unsafe exposure to formaldehyde can irritate the eyes, skin and respiratory system; formaldehyde is also recognised as a human carcinogen. Insecticides such as dichlorvos can cause acute poisoning when exposure is sufficient, affecting the nervous system and potentially threatening life.
These are not interchangeable hazards, and it would be scientifically inaccurate to attribute every illness in Nigeria to chemically treated food. Nor should every case of cancer, kidney disease or infertility be blamed on food preservatives without evidence establishing the connection. Nevertheless, the potential for serious harm is sufficient to justify preventive action, particularly where substances not approved for food use are deliberately applied to products intended for human consumption.
The danger is not limited to the person who eats the food. Traders and other handlers may be exposed while mixing, applying or storing chemicals. Children, pregnant women, older people and individuals with existing health vulnerabilities may face particular risks from certain contaminants. Where contaminated food enters informal distribution networks, identifying its origin and protecting consumers can become difficult.
Yet the human-health implications are only one part of this story. Another consequence deserves greater attention: the food that is ultimately wasted.
Imagine a trader who purchases several baskets of mangoes or plantains from a farmer. Hoping to accelerate ripening and improve sales, the trader uses an unsafe chemical treatment. The fruits arrive at the market with an attractive yellow colour, and customers initially show interest. Then a buyer becomes suspicious. Another hears a warning from a neighbour. A customer notices an unusual appearance or learns that a particular batch may have been treated with a prohibited substance. Confidence begins to disappear.
Some buyers walk away. Others refuse to return. If suspicion spreads through the market, even produce that has not been independently confirmed as contaminated may become difficult to sell.
For the trader, the result can be devastating. Money has already been invested in purchasing, transporting and displaying the produce. The fruits continue to ripen and deteriorate. Without sufficient sales, the trader may be forced to reduce prices, absorb a loss or discard the unsold stock. The farmer who supplied the produce may also suffer if traders become reluctant to purchase subsequent harvests from the same source.
This is how unsafe food handling can turn into an economic and food-waste problem.
It is important to distinguish between food that has been confirmed to contain a hazardous substance and food that is rejected because of suspicion. Both situations can result in commercial losses, but they require different responses. Confirmed contaminated food must be managed safely and prevented from entering the food chain again. Where suspicion has not been verified, competent authorities should investigate and test the product rather than allowing rumours alone to determine its fate.
The same concern applies to fish, meat and grains. If consumers suspect that fish has been treated with formalin or that beans have been sprayed with an insecticide, they may reject the products entirely. Where contamination is confirmed, that rejection may prevent illness. But where the suspicion affects safe products from the same market or supply chain, the resulting loss can damage the livelihoods of honest farmers and traders.
The lesson is not that consumers should ignore warnings to prevent waste. Public health must come first. Rather, the lesson is that preventing contamination in the first place is better than confronting a market full of potentially unsafe food that nobody trusts.
Food waste carries its own environmental consequences. When discarded fruits, vegetables, meat and other organic materials decompose in dumpsites or poorly managed landfills, they generate methane, a potent greenhouse gas. Leachate from decomposing waste can contaminate surrounding soil and water, particularly where waste management systems are inadequate. Food waste also represents wasted water, energy, fertiliser, fuel, labour and land used during production and transportation.
Where discarded food contains hazardous chemicals, the disposal challenge becomes more complicated. Chemicals may enter drainage channels, soil or water if contaminated products are dumped indiscriminately. Empty chemical containers may also pose risks if they are abandoned in markets or reused for household purposes. The precise environmental consequences depend on the chemical involved, its concentration and the disposal conditions, but the principle is clear: unsafe food handling can transfer a problem from the marketplace into the wider environment.
Nigeria already faces substantial challenges in reducing post-harvest losses, especially where farmers and traders lack reliable cold storage, suitable transport, effective packaging and access to processing facilities. Introducing dangerous chemicals into this system does not solve the underlying problem. It can create an additional one.
There are safer ways to preserve food and manage ripening. Appropriate refrigeration and freezing can help preserve fish and meat. Drying, smoking under controlled conditions, fermentation, canning and hygienic packaging can extend the shelf life of suitable foods. Properly managed grain storage, moisture control and approved pest-control methods can reduce losses. For fruits, natural ripening and appropriately controlled ethylene-based systems offer alternatives to prohibited calcium carbide treatment.
These solutions require investment, but the investment should be viewed against the cost of illness, discarded food, damaged reputations and lost livelihoods. Affordable cold-chain infrastructure, shared storage facilities, improved rural roads and access to safe processing equipment can help small-scale traders preserve their products without resorting to dangerous shortcuts.
Government also has an important responsibility. NAFDAC, relevant agricultural authorities, state environmental agencies and local governments must strengthen surveillance, laboratory testing and public education. Enforcement should target those who deliberately introduce prohibited substances into food, while giving legitimate food businesses practical guidance on compliant preservation methods.
Nigeria’s NAFDAC Food Hygiene Regulations 2025 provide a framework addressing food safety management, temperature control, product analysis, complaints, recalls and food-waste disposal. The challenge is to ensure that applicable requirements are implemented effectively across formal businesses and informal markets. Inspections should be risk-based, testing should be accessible, and offenders should face proportionate consequences where violations are established.
Market associations and transport operators should also be involved. Traders need to understand that preserving food is not the same as concealing spoilage or artificially changing its appearance. Consumers, meanwhile, need reliable channels for reporting suspicious products and obtaining accurate information. Public communication must be evidence-based: frightening people with unverified claims can undermine confidence in safe food just as surely as concealing genuine contamination can endanger lives.
Ultimately, Nigeria must recognise that food safety, food security and environmental protection are interconnected. A country cannot sustainably improve access to food while allowing unsafe handling practices to threaten consumers and undermine trust in the market. Neither can it tackle food waste effectively without addressing the practices that cause produce to become unsaleable, unsafe or unnecessarily discarded.
The objective should be to protect both the food and the people who depend on it. Farmers deserve markets for their harvests. Traders deserve preservation methods that protect their investments without exposing them or their customers to hazardous substances. Consumers deserve food that is safe, affordable and honestly represented. Communities deserve protection from the environmental consequences of poorly managed waste.
The solution is not to abandon food preservation. It is to make preservation safe, accessible and accountable.
Every basket of fruit discarded because of an avoidable food-safety failure represents more than lost commercial value. It may represent a farmer’s labour, a trader’s savings, a household’s missed opportunity to obtain nutritious food and resources wasted along the supply chain. Every contaminated meal prevented represents a potential public-health benefit. Every safe preservation facility established represents an opportunity to protect both livelihoods and the environment.
Nigeria must therefore move beyond reacting to food-safety scares after they emerge. It must invest in prevention, enforce existing rules, strengthen scientific testing and make safer preservation technologies available to those who need them most.
Food preservation should protect food, not poison it. And efforts to prevent food waste should never create a greater threat to human health and the environment.
