Exploring the impact of pesticide use by urban cultivators in South-Western Nigeria on public health and food safety
When Yakub Ahmad, a 27-year-old farmer from Ilora in Oyo State, sprayed his one-acre maize crop in April 2024, he was thinking about weeds, not welfare. A leak in his Gramoxone container allowed the herbicide to trickle down his abdomen to his private parts.
His story represents thousands of invisible victims across Southwestern Nigeria, where urban and peri-urban cultivators feed growing cities while potentially compromising public health. The very chemicals promising food security are creating a silent health crisis that reaches from farms directly to urban dinner tables.
Farmers affected by pesticide exposure in Southwestern Nigeria
Pesticide exposure can lead to both immediate symptoms and chronic health conditions.
Recent scientific studies reveal alarming patterns in pesticide use across Southwestern Nigeria. A 2025 assessment published in Frontiers in Agronomy examined 472 farmers across Ogun, Ondo, and Oyo States, finding that herbicides dominate the pesticide landscape 2 .
| Pesticide Type | Specific Pesticide | Percentage of Farmers Using |
|---|---|---|
| Herbicides | Glyphosate | 81.9% |
| Paraquat | 69.1% | |
| Insecticides | Dichlorvos/DDVP | 56.5% |
| Lambda-cyhalothrin | 49.8% | |
| Fungicides | Mancozeb | 38.6% |
| Pesticide Mixtures | Imidacloprid & Thiram | 44.5% |
Nigeria's National Agency for Food and Drug Administration and Control banned paraquat in January 2024 due to severe risks to human health, animals, and the environment 1 . Yet it remains widely available and popular among urban cultivators.
Economic reality, not recklessness, drives this chemical dependence. A bottle of Gramoxone (containing paraquat) costs ₦5,000 (approximately $3.40), while hiring labor for manual weeding would cost between ₦58,000 and ₦73,000 (equivalent to $40-50) 1 .
The dangers extend beyond choice of chemicals to how they're handled throughout the farming process. Research among tomato producers in Northern Nigeria reveals startling safety gaps that likely mirror practices among Oyo State's urban cultivators 5 :
45% of farmers reuse empty pesticide containers for other purposes
14% discard containers directly on the farm
15% burn containers in open fires
40% harvest tomatoes within 1-5 days after pesticide application, violating the 7-day pre-harvest interval guideline
Perhaps most alarmingly, over 66% of agricultural workers in Rivers State reported wearing the same contaminated clothing in their homes after working in fields, potentially exposing children and family members to harmful residues .
The health consequences manifest in both immediate symptoms and chronic conditions. A 2025 study of Oyo State farmers documented concerning health patterns 6 :
"When a pollutant enters human tissue, it begins to accumulate before expressing its toxic effects — that's why [such chemicals] are called persistent," explains Michael Odey, environmental toxicologist at the University of Calabar in Nigeria. He notes that major accumulation may trigger cancer and cardiovascular diseases, with children and the elderly being particularly vulnerable because their bodies metabolize these substances more slowly 1 .
A groundbreaking 2025 study published in the International Journal of Environmental Research and Public Health investigated the determinants of safe pesticide handling among rural farmers in Oyo State, with crucial implications for urban cultivators 6 .
The research team employed a cross-sectional design using 2-stage cluster sampling techniques to select Ido and Ibarapa Central Local Government Areas. They interviewed 383 farmers via structured questionnaires, assessing:
The researchers statistically analyzed correlations between training, knowledge levels, and safety practices to identify what truly drives behavioral change 6 .
The findings revealed striking patterns. While 73.5% of farmers had good safety and health knowledge, and 72.3% demonstrated safe handling practices, specific risky behaviors persisted 6 :
Use empty pesticide containers for other purposes
Blow nozzle tips with their mouth to unclog them
Consistently wear coveralls, gloves, and masks
Most significantly, the research identified two powerful predictors of safety:
The consequences of unregulated pesticide use extend far beyond individual farms. Nigeria loses approximately $362.5 million annually due to the European Union's ban on Nigerian beans, primarily citing excessive pesticide residues 4 . Up to 76% of Nigerian agricultural exports face rejection on safety grounds, creating a devastating economic impact 4 .
This chemical exposure is contributing to a growing health crisis. Nigeria now records an estimated 127,000 new cancer cases annually, though leading oncologists warn the actual figure is likely double, as many cases go undiagnosed until late stages 4 . Similarly, more than 2 million Nigerians suffer from chronic kidney disease, with most presenting late for treatment due to cost barriers 4 .
New cancer cases annually in Nigeria
Nigerians with chronic kidney disease
Annual dialysis subsidy for just 2% of patients
The economic burden is staggering. The federal government now subsidizes dialysis treatments at approximately ₦158.08 billion annually for just 40,000 patients—a mere 2% of those in need 4 .
The research is clear: education works. "The first line of defense is knowledge," emphasizes Dr. Odey. "Farmers must understand what they are handling, and governments must ensure these products don't reach their hands in the first place" 1 .
Successful training programs, like those implemented by Norina Farms in Rivers State, adopt a community-based, family-oriented approach rather than focusing solely on individual farmers. These initiatives address critical gaps in proper storage, container disposal, and personal protective equipment use .
Integrated Pest Management (IPM) presents a promising alternative by combining biological, cultural, physical, and chemical tools to minimize harm to human health and the environment 2 . Global experience demonstrates that phasing out highly hazardous pesticides doesn't necessarily reduce food production when paired with alternatives and farmer training 4 .
Back in Oyo State, Yakub Ahmad's scars may have faded, but his perspective has permanently changed. "I just wanted my maize to grow," he said quietly. "Now, I know the danger, but if we stop using these chemicals, how do we feed our families?" 1
His dilemma captures Nigeria's precarious balancing act between food security and public health. As urban agriculture expands to feed growing cities, the choices made by farmers, policymakers, and consumers will determine whether our food systems nourish or harm.
The science clearly shows that the price of cheap pesticides is ultimately paid in hospital wards, through export rejections, and in the silent accumulation of toxins in our bodies. But through education, regulation, and sustainable alternatives, Nigeria can cultivate a future where feeding cities doesn't come at the cost of poisoning them.