Kano State’s Consumer Protection Council has shut a number of warehouses at Dawanau Market, one of West Africa’s largest grain trading hubs, after inspectors found traders preserving stored beans with agricultural pesticides instead of chemicals approved for food storage. The action, reported by Daily Trust, follows complaints and testing that identified the practice as widespread enough to warrant an enforcement sweep rather than isolated warnings.
Nigeria’s food and drug regulator, NAFDAC, has separately flagged pesticide-preserved beans as a recurring public health risk in grain markets across the country’s north, where traders have used unapproved chemicals such as phostoxin and other agricultural pesticides to protect stored legumes from weevils and other pests during long storage periods. Officials say the chemicals, intended for field use rather than food preservation, can leave residues above safe limits when applied directly to beans destined for consumption.
Dawanau Market supplies grain not only to Kano but to markets and mills across northern Nigeria and into neighbouring countries, making contamination there a concern that extends well beyond the city. Traders found using the banned preservation method face warehouse closure and, under existing consumer protection rules, the risk of further sanctions if the practice recurs.
A storage problem with a public health cost
Bean and grain traders have long cited post-harvest losses to pests as one of the biggest costs of doing business in markets like Dawanau, where produce can sit in storage for months awaiting buyers. Approved fumigants exist for this purpose, but they are often more expensive and harder to source consistently than agricultural pesticides already circulating for farm use, which officials say creates a persistent temptation to substitute one for the other.
Public health researchers have previously linked pesticide residue in stored grain to acute poisoning incidents and longer-term health concerns when consumption is repeated over time, giving regulators grounds to treat the practice as more than a labelling or quality issue. Kano’s enforcement action is the latest in a series of market inspections across northern Nigeria this year aimed at tightening the gap between farm-level pesticide use and food-safety standards at the point of sale.
Enforcement without an alternative risks recurrence
Market associations in Kano have broadly supported stricter enforcement in principle but argue that warehouse closures alone will not solve the underlying storage problem unless cheaper, accessible approved fumigants are made available to traders at scale. Agricultural economists tracking the market say the episode illustrates a wider tension in Nigeria’s grain trade: post-harvest loss prevention and food safety are often treated as separate problems, when for a trader deciding what to spray on a warehouse of beans they are really the same decision. Kano authorities say further inspections across the city’s grain markets are planned in the coming weeks.
A market too big to police by closure alone
Dawanau’s scale, traders there handle volumes large enough to influence bean prices across several northern states, means that any disruption to its warehouses has knock-on effects for buyers well beyond Kano city. Market leaders have asked the state government to pair enforcement with a subsidy or bulk-procurement scheme for approved fumigants, arguing that price is the main reason traders reach for agricultural pesticides instead, which are often a fraction of the cost of food-grade alternatives and are already stocked locally for farm use. Consumer rights advocates in Kano say they want the council to publish results of its market testing regularly, rather than only after enforcement action, so that buyers further down the supply chain have some independent signal of which warehouses have passed inspection.
