By STELLA JOHNSON OGBOVOVEH

From Farm to Market: How Post-Harvest Pressures Are Driving Fruit-Safety Concerns

A colourful display of ripe bananas, plantains and mangoes can be hard to resist.

For millions of Nigerians, these fruits form part of regular meals and provide an accessible source of nutrients. However, experts are drawing attention to what may happen before the produce reaches the consumer.

They warn that inappropriate use of pesticides and other chemicals, particularly during post-harvest handling and ripening, can create food-safety risks.

The warning does not mean that every attractive or chemically treated fruit is dangerous. Instead, experts say the concern centres on what chemical was used, how much was applied, whether it was authorised and how long consumers are exposed to the residue.

A Food-Safety Concern Beyond Ripening

Fruit ripening is a natural biological process. Ethylene, a plant hormone, plays a central role in the ripening of many fruits.

The problem emerges when traders or handlers turn to inappropriate substances to accelerate the process or preserve produce.

Nutrition expert Pharm. Orume Beatrice said fruits exposed to inappropriate chemicals, excessive concentrations or residues remaining because required pre-harvest intervals were not observed could expose consumers to potentially harmful substances.

The possible effects vary widely.

According to her, acute exposure can produce gastrointestinal symptoms such as nausea, vomiting, abdominal cramps and diarrhoea. Some exposures can also produce headache, dizziness, weakness, excessive sweating, blurred vision, skin or eye irritation and breathing difficulties.

Severe poisoning, depending on the chemical, can involve neurological symptoms.

WHO likewise notes that pesticide exposure can cause acute or chronic effects depending on the amount and route of exposure.

Not Every Residue Means Poisoning

The distinction between chemical residue and unsafe chemical exposure is crucial.

Pesticide residues can remain on or in food after legitimate agricultural use. For that reason, regulators and international food-safety bodies establish maximum residue limits.

FAO describes an MRL as the maximum concentration of a pesticide residue legally permitted in or on food or feed. Such limits are based on good agricultural practice and toxicological considerations.

Therefore, finding a residue does not automatically establish that a food is dangerous.

The concern is whether exposure exceeds established safety thresholds or involves a substance that should not be present in the food at all.

FAO and WHO dietary assessments consider both short-term and long-term exposure. They use measures such as the Acute Reference Dose and Acceptable Daily Intake to assess potential consumer risks.

The Cumulative Exposure Question

Even when an individual serving produces no immediate symptoms, experts say repeated exposure deserves attention.

Orume explained that some chemicals can affect particular organs or biological systems after prolonged exposure.

Possible concerns include effects on the nervous system, liver, kidneys and immune system. Certain substances may also interfere with hormonal functions or reproductive and developmental processes.

Cancer risk, she noted, depends on the specific chemical and exposure circumstances.

That qualification matters.

Rather than suggesting that every chemically treated fruit causes cancer, experts emphasise that health effects must be assessed according to the substance, dose and duration of exposure.

WHO’s pesticide-residue assessments similarly recognise both acute and chronic dietary exposure in evaluating consumer safety.

The Economics Behind the Practice

For agricultural stakeholders, however, the problem cannot be separated from the economics of perishability.

Adebowale Onafowora said fruits are frequently harvested before full ripeness because they must travel from farming communities to distant urban markets.

That strategy can reduce damage during transportation.

Yet it also creates a second problem.

Once the produce arrives, traders have only a limited period in which to sell it. In hot conditions and without adequate storage, deterioration can occur quickly.

For traders operating with borrowed money, unsold fruit can mean direct financial losses.

Onafowora said the lack of temperature-controlled aggregation and storage facilities can therefore create incentives for unsafe practices.

Weak Infrastructure Adds Pressure

Prince Oyewumi Oyedele Oyetunde identified inadequate storage, unreliable electricity, transportation difficulties, consumer demand and limited awareness of approved substances among factors that can encourage chemical misuse.

Okewole also pointed to poor roads, inadequate cold-storage infrastructure and the absence of guaranteed markets.

The result is a chain of pressure stretching from the farmer to the trader and, eventually, the consumer.

A farmer wants to minimise post-harvest losses.

A trader wants produce that will remain marketable.

A consumer wants attractive, affordable fruit.

Without proper infrastructure and effective oversight, those competing pressures can create room for unsafe shortcuts.

Safer Technologies Can Reduce Losses

Stakeholders say the solution should combine enforcement with better agricultural infrastructure.

Onafowora recommended controlled application of food-grade ethylene gas where appropriate. He also pointed to natural ripening methods involving ethylene released by ripe fruits under controlled conditions.

Meanwhile, modified-atmosphere packaging and zero-energy cooling chambers can help extend the useful life of some produce.

Oyedele recommended harvesting at appropriate maturity stages and improving refrigeration, ventilation, temperature and humidity control.

Okewole added solar-powered cold rooms, pre-cooling where appropriate and better packaging to the list of possible interventions.

Using crates instead of sacks can also reduce bruising during transportation.

When Fresh Fruit Becomes Processed Food

Another option is to reduce dependence on the fresh-fruit market.

Okewole suggested processing produce into juice, purée, dried products or pulp when market prices make fresh sales unattractive.

Such processing can reduce pressure to sell immediately and may provide farmers and traders with another route for managing surplus produce.

However, processing itself requires appropriate hygiene, storage and regulatory controls.

Regulation Remains Critical

Food-safety experts also emphasise the role of regulation.

NAFDAC’s pesticide-registration framework requires assessment of pesticide products, including information on toxicity, reproductive effects, environmental fate and residue levels.

The agency also maintains guidance covering pesticide registration, restricted agrochemicals and food-safety practices.

According to Orume, enforcement measures for inappropriate chemical use can include seizure or destruction of affected produce, withdrawal from sale, fines, licence suspension or revocation and, depending on the circumstances, prosecution.

Such measures are intended to protect consumers while encouraging compliance throughout the food chain.

Consumers Need Information, Not Fear

The growing concern over chemically treated fruits should therefore not translate into blanket suspicion of bananas, plantains or mangoes.

Fruits remain an important part of a healthy diet.

The more useful question is whether the food system can guarantee that produce is grown, harvested, ripened and stored safely.

That requires stronger surveillance, better residue testing, clearer awareness among farmers and traders, improved storage infrastructure and consistent enforcement.

It also requires investment in practical alternatives so that traders are not forced to choose between rapid deterioration and potentially unsafe chemical shortcuts.

In the end, food safety begins long before a consumer picks a fruit from a market stall.

It starts on the farm, continues through transportation and storage, and ends only when the food reaches the plate.

Protecting consumers therefore means strengthening every link in that chain.