Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya

BACKGROUND In Kenya, the extensive use of agrochemicals in fruits and vegetable farming raises concerns about pesticide residues in agricultural products including tomato fruits. There are still a number of highly hazardous pesticides including mancozeb, glyphosate acid, chlorpyrifos, acephate and c...

Full description

Bibliographic Details
Main Authors: Obar, J.A., Kwoba, E., Omosa, Esther, Ekaya, Wellington, Fèvre, Eric M., Onono, J.
Format: Journal Article
Language:Inglés
Published: Wiley 2026
Subjects:
Online Access:https://hdl.handle.net/10568/176887
_version_ 1855536165388550144
author Obar, J.A.
Kwoba, E.
Omosa, Esther
Ekaya, Wellington
Fèvre, Eric M.
Onono, J.
author_browse Ekaya, Wellington
Fèvre, Eric M.
Kwoba, E.
Obar, J.A.
Omosa, Esther
Onono, J.
author_facet Obar, J.A.
Kwoba, E.
Omosa, Esther
Ekaya, Wellington
Fèvre, Eric M.
Onono, J.
author_sort Obar, J.A.
collection Repository of Agricultural Research Outputs (CGSpace)
description BACKGROUND In Kenya, the extensive use of agrochemicals in fruits and vegetable farming raises concerns about pesticide residues in agricultural products including tomato fruits. There are still a number of highly hazardous pesticides including mancozeb, glyphosate acid, chlorpyrifos, acephate and cypermethrin amongst many others that are still used in Kenya despite being banned in Europe due to harmful effects on humans and other animals. This study aimed to evaluate the residual levels of cypermethrin pesticide in locally produced tomato in Laikipia County, Kenya. Also, the study identified some practices that lead to pesticide residual levels in tomatoes. A total of 82 tomato samples were analyzed for pesticide residues following extraction using QuEChERS method and analyzed for the presence of synthetic pyrethroids (<i>cis</i>- and <i>trans</i>-alpha-cypermethrins) pesticides using gas chromatography–mass spectrometry (GC–MS). RESULTS The results indicated that 58.54% of tomato samples showed the presence of residues of both pesticides, with none exceeding maximum residue levels (MRLs). The mean residues concentration for <i>trans</i>-alpha-cypermethrin was 23.82, 11.84 and 11.12 ppm in north, east and west Laikipia sub-counties respectively. While that for <i>cis</i>-alpha-cypermethrin was 13.58, 5.63 and 4.62 ppm in north, west and east Laikipia respectively. CONCLUSIONS Despite tested pesticide levels in tomatoes being within legal limits, their frequent detection is concerning due to tomatoes being eaten raw. This indicates a potential health risk and highlights the need for farmer training on the banned pesticide cypermethrin and expanded future research.
format Journal Article
id CGSpace176887
institution CGIAR Consortium
language Inglés
publishDate 2026
publishDateRange 2026
publishDateSort 2026
publisher Wiley
publisherStr Wiley
record_format dspace
spelling CGSpace1768872025-12-22T09:05:35Z Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya Obar, J.A. Kwoba, E. Omosa, Esther Ekaya, Wellington Fèvre, Eric M. Onono, J. food safety health pesticide residues tomatoes vegetables BACKGROUND In Kenya, the extensive use of agrochemicals in fruits and vegetable farming raises concerns about pesticide residues in agricultural products including tomato fruits. There are still a number of highly hazardous pesticides including mancozeb, glyphosate acid, chlorpyrifos, acephate and cypermethrin amongst many others that are still used in Kenya despite being banned in Europe due to harmful effects on humans and other animals. This study aimed to evaluate the residual levels of cypermethrin pesticide in locally produced tomato in Laikipia County, Kenya. Also, the study identified some practices that lead to pesticide residual levels in tomatoes. A total of 82 tomato samples were analyzed for pesticide residues following extraction using QuEChERS method and analyzed for the presence of synthetic pyrethroids (<i>cis</i>- and <i>trans</i>-alpha-cypermethrins) pesticides using gas chromatography–mass spectrometry (GC–MS). RESULTS The results indicated that 58.54% of tomato samples showed the presence of residues of both pesticides, with none exceeding maximum residue levels (MRLs). The mean residues concentration for <i>trans</i>-alpha-cypermethrin was 23.82, 11.84 and 11.12 ppm in north, east and west Laikipia sub-counties respectively. While that for <i>cis</i>-alpha-cypermethrin was 13.58, 5.63 and 4.62 ppm in north, west and east Laikipia respectively. CONCLUSIONS Despite tested pesticide levels in tomatoes being within legal limits, their frequent detection is concerning due to tomatoes being eaten raw. This indicates a potential health risk and highlights the need for farmer training on the banned pesticide cypermethrin and expanded future research. 2026-01 2025-10-08T12:08:44Z 2025-10-08T12:08:44Z Journal Article https://hdl.handle.net/10568/176887 en Limited Access Wiley Obar, J.A., Kwoba, E., Omosa, E., Ekaya, W., Fèvre, E. and Onono, J. 2026. Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya. Pest Management Science.
spellingShingle food safety
health
pesticide residues
tomatoes
vegetables
Obar, J.A.
Kwoba, E.
Omosa, Esther
Ekaya, Wellington
Fèvre, Eric M.
Onono, J.
Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title_full Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title_fullStr Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title_full_unstemmed Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title_short Analysis of alpha-cypermethrin pesticide residues along the value chain of tomato from Laikipia County, Kenya
title_sort analysis of alpha cypermethrin pesticide residues along the value chain of tomato from laikipia county kenya
topic food safety
health
pesticide residues
tomatoes
vegetables
url https://hdl.handle.net/10568/176887
work_keys_str_mv AT obarja analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya
AT kwobae analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya
AT omosaesther analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya
AT ekayawellington analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya
AT fevreericm analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya
AT ononoj analysisofalphacypermethrinpesticideresiduesalongthevaluechainoftomatofromlaikipiacountykenya