NAIROBI, Kenya, July 17 — Nearly eight out of every 10 vegetables sampled from Kenyan markets contain detectable pesticide residues, with one in every three exceeding internationally accepted safety limits, according to a new study unveiled Friday during a national dialogue on food safety in Nairobi.
The findings, presented at the Food Safety in Kenya: From Evidence to Action forum held at the Kenya School of Monetary Studies, have reignited debate over pesticide regulation, food safety oversight and consumer protection, even as researchers assured Kenyans that simple household food preparation methods can significantly reduce exposure.
The forum, convened by the Kenya Organic Agriculture Network (KOAN) in partnership with the Route to Food Initiative and the Heinrich Boll Foundation Nairobi Office, brought together government officials, researchers, farmers, civil society organisations, development partners and consumer advocates to discuss practical and policy interventions aimed at strengthening Kenya's food safety systems.
Researchers from the University of Nairobi's Department of Public Health, Pharmacology and Toxicology, working alongside SGS Kenya Limited, analysed 45 samples of tomatoes, kale, spinach and onions sourced from major markets.
Their findings showed that 78 per cent of the vegetables contained detectable pesticide residues, while 15 samples—equivalent to one-third of those tested—contained at least one pesticide residue above the European Union Maximum Residue Limits (MRLs).
Tomatoes recorded the highest number of samples exceeding the safety limits, followed by spinach and kale, while onions emerged as the least contaminated vegetable among those analysed.
The researchers also identified eight pesticide active ingredients exceeding regulatory limits, seven of which are classified by the World Health Organization as moderately hazardous.
Opening the forum, Joachim Paul, Regional Director of the Heinrich Boll Foundation Nairobi Office, said the report should be viewed as an opportunity to strengthen Kenya's food safety systems rather than alarm consumers.
"Today's launch is not simply about releasing another report. It is about placing credible scientific evidence into the hands of policymakers, regulators, farmers, consumers, public health practitioners and civil society organisations so that it can inform decisions and stimulate action," Paul said.
He noted that although pesticides remain essential in controlling crop pests and improving yields, their misuse—including excessive application, failure to observe recommended pre-harvest intervals and use on crops for which they are not registered. continues to expose consumers, farm workers and the environment to unnecessary risks.
Paul emphasized that responsibility for food safety should not rest solely with consumers.
"Household food preparation is a complementary protective measure; it is not a substitute for responsible pesticide use and effective regulation. Consumers should not be expected to correct, in their kitchens, failures that originate at the point of pesticide registration, sale or application."
Despite the alarming findings, the report also offered practical solutions that households can adopt immediately.
Researchers evaluated several food preparation techniques commonly used in Kenyan homes, including washing vegetables under running water, blanching, soaking them in salt, baking soda and vinegar solutions before cooking.
The study found that soaking vegetables in a two per cent salt solution for 15 minutes, washing them thoroughly under running water and then cooking them reduced pesticide residues by an average of 72.4 per cent, making it the most effective method tested.
Washing followed by blanching reduced residues by an average of 70 per cent, while baking soda soaking followed by washing and cooking achieved an average reduction of 69.8 per cent. Onions responded best to treatment, with residue levels dropping by nearly 99 per cent after washing and blanching.
Participants at the forum also witnessed live kitchen demonstrations illustrating how the evidence-based preparation methods can be incorporated into everyday cooking.
Speaking during the event, KOAN Executive Director Eustace Kiare said the report provides evidence that can guide action across the food value chain.
"Food safety is everyone's responsibility. This dialogue brings together evidence, experience and diverse voices to identify practical actions that can strengthen Kenya's food system, from the farm to the consumer's table."
Route to Food Initiative Programme Coordinator Dr. Harun Warui said while consumers can reduce pesticide exposure through proper food preparation, the long-term solution lies in addressing the problem at its source.
"The right to food is not only about having enough to eat. It is also about ensuring that the food people consume is safe. This research provides evidence that can inform policy, support farmers and equip consumers with practical knowledge."
Warui called for stronger regulation of pesticides, routine residue monitoring, enhanced farmer training on responsible pesticide use and increased investment in agroecological farming systems that reduce reliance on hazardous chemicals.
The report recommends strengthening enforcement of pesticide regulations, expanding farmer education on Good Agricultural Practices and Integrated Pest Management, improving food traceability from farms to markets, institutionalising routine pesticide residue surveillance and providing consumers with practical, science-based food safety information.
Researchers, however, cautioned that the findings should not be interpreted as a nationwide assessment of all vegetables sold in Kenya.
Instead, they described the study as an important scientific snapshot that mirrors concerns raised by previous research and highlights the need for continued monitoring and stronger oversight of the country's food systems.
As discussions concluded, stakeholders agreed that ensuring food safety requires shared responsibility among regulators, farmers, researchers, traders and consumers.
For many Kenyans who buy vegetables daily from local markets and roadside vendors, the message from the forum was clear: while simple kitchen practices can substantially reduce pesticide residues before meals are prepared, lasting food safety will ultimately depend on stronger regulation and safer farming practices long before produce reaches the market shelves.
