10/09/2026
Thank you, Iskolar ng Bayan, for featuring one of our important studies on pesticide residues in vegetables. We appreciate the opportunity to share research that contributes to food safety and consumer awareness.
Here’s a brief summary of what the study found:
The study tested 443 vegetable samples from markets and stalls in Southern Luzon for pesticide residues. About 16% tested positive, including 12.2% of organic-labeled vegetables and 18.3% of conventional vegetables. The detection of pesticide residues in organic-labeled vegetables is particularly concerning, as it may indicate mislabeling or non-compliance with organic farming practices.
Bitter gourd, pechay, and tomatoes had the highest positivity rates. Further testing of selected samples found that one organic-labeled vegetable exceeded the allowed pesticide residue limit.
Overall, the study highlights the importance of regular monitoring of pesticide residues, proper pesticide use, and better education for farmers on pesticide safety and proper pre-harvest intervals.
CHECK BEFORE TRUSTING 🥬⚠️
Some vegetables sold with an “organic” label tested positive during a Philippine study screening produce for pesticide residues.
Researchers John Julius P. Manuben, Jasper A. Sarmiento, and Cristina M. Bajet of the UP Los Baños National Crop Protection Center examined 443 vegetable samples collected from selected markets and stalls in Southern Luzon between January 2016 and March 2018.
The samples included 262 conventionally grown vegetables and 181 vegetables labeled organic.
Using the Rapid Bioassay for Pesticide Residues, the team screened the vegetables for organophosphate and carbamate insecticides. The test identifies samples showing enzyme inhibition associated with these pesticide groups.
Results showed that 70 of the 443 samples, or 15.8%, screened positive for pesticide residues.
Among conventional vegetables, 18.3% tested positive. Among those labeled organic, 12.2% also produced positive screening results. Bitter gourd, pechay, and tomato recorded the highest positivity rates among the vegetables examined.
The researchers selected six samples for additional testing through gas chromatography–mass spectrometry, a more specific laboratory method. One organic-labeled vegetable was confirmed to contain pesticide residue above the existing maximum residue limit.
However, the findings do not mean that all organic vegetables contain pesticides. The study involved produce from selected locations, and only six screening-positive samples underwent confirmatory analysis.
The term “organic-labeled” also refers to how the vegetables were marketed and does not necessarily establish that every product had undergone formal organic certification.
The results raised concerns about possible mislabeling or failure to follow organic-farming standards. The researchers called for regular residue monitoring, stronger enforcement, and better education on safe pesticide practices.
Published in the June 2022 issue of the Philippine Journal of Science, the study shows why food labels must be supported by proper farming practices, certification, and testing.
