By Paul Aondoakaa 

LAGOS — Former Vice-President Yemi Osinbajo has raised fresh concerns about food safety in Nigeria, warning that chemicals used in farming, fruit ripening and food preservation could expose consumers to health risks.

Osinbajo spoke on August 28 at the Open Day for Gardeners’ Seminar in Lagos, themed “Leaving the Earth Better Than We Found It.” The event brought food production and environmental concerns into focus, with Osinbajo urging greater attention to what reaches Nigerian consumers’ tables.

The former vice-president recounted a personal experience involving his wife, Dolapo Osinbajo, who, according to him, developed frequent headaches after making freshly squeezed orange juice a daily habit.

He said she had stopped consuming carbonated drinks years earlier and considered the fresh orange juice a healthier alternative. However, after the headaches persisted, she reviewed what she was consuming and eventually sent a batch of the juice for laboratory testing.

According to Osinbajo, the laboratory result described the freshly squeezed orange juice as “not fit for human consumption.”

He did not disclose the laboratory involved, the specific contaminant identified, the concentration detected or the test report itself in the account provided. As a result, the reported laboratory finding cannot independently establish that the oranges caused Dolapo Osinbajo’s headaches or identify the specific substance responsible.

Osinbajo, however, used the experience to highlight broader concerns about the handling of fruits and vegetables in Nigeria.

He said farmers sometimes use dangerous pesticides on produce, while some fruit sellers use chemicals to accelerate ripening or extend shelf life.

One chemical he specifically mentioned was calcium carbide, which he said is sometimes used to make fruits such as bananas, mangoes, pawpaws and tomatoes appear ripe more quickly.

Research conducted in Ado-Ekiti provides some evidence that the practice exists. A 2024 study published in Discover Public Health surveyed 20 fruit sellers and found that 10 of them — 50 per cent — reported using calcium carbide for fruit ripening. The study also found that 90 per cent of the sellers had poor knowledge of the health effects associated with calcium carbide use.

However, the study's small sample means its findings should not be treated as representative of all fruit sellers in Ekiti State or Nigeria.

A separate study among fruit sellers in Uyo also documented calcium-carbide use, reporting that 25.1 per cent of respondents identified calcium carbide among the methods used for fruit ripening. The research found that natural ripening remained the dominant practice among respondents.

Evidence from Lagos points to a wider food-preservation concern.

A 2023 study involving 50 fruit and vegetable retailers across selected Lagos markets found that 22 respondents, representing 44 per cent, used chemical preservatives, primarily pesticides. The chemicals reported included Gammalin-20, Sniper, aluminium phosphide, DDT, calcium carbide and brodifacum.

The findings do not mean that all fruits sold in Nigerian markets are chemically contaminated, nor do they establish that consuming chemically treated fruit will necessarily cause a particular illness. They do, however, point to the need for stronger surveillance, enforcement and public education around food handling.

That distinction is important for consumers.

The mere appearance of a fruit, its speed of ripening or a person's symptoms cannot reliably establish whether chemicals were used. Laboratory testing is required to identify particular contaminants and determine whether residues exceed applicable safety limits.

Osinbajo called for stronger enforcement, increased public awareness, safer agricultural and preservation practices and greater consumer vigilance.

His warning also raises a wider accountability question: how effectively are food-safety authorities monitoring what is being applied to fruits and vegetables before those products reach consumers?

For Nigerians, particularly those who increasingly rely on fresh fruits and vegetables as part of healthier diets, food safety cannot depend solely on individual vigilance. Farmers, traders, regulators, laboratories and consumers all have roles to play.

For Benue and other major agricultural-producing states, the issue is particularly relevant. Agricultural production is central to livelihoods and the wider economy, while fruits and vegetables move through complex supply chains before reaching markets and households.

The priority, therefore, is not to create fear around fresh produce but to ensure that food marketed to Nigerians is produced, handled and preserved according to established safety standards.

Osinbajo’s personal account has brought renewed attention to that responsibility. But determining the scale of the problem requires more than individual experiences: it requires transparent laboratory testing, routine market surveillance, enforcement of food-safety rules and publication of credible data on contaminants detected in food.

Until such evidence is available, consumers should distinguish between a warning about potential risks and proof that a particular fruit or illness was caused by chemical contamination.