Abstract:
Many different herbicides have been suggested to control weeds in tea fields. Among
them, glyphosate has become a popular herbicide among farmers because it effectively
controls a wide range of weeds. Glyphosate residues in the environment and on plants
have increased as a result of its widespread use. Thus, the study aimed to determine the
persistence of glyphosate in tea leaves and tea soils in herbicide-applied and herbicidefree
tea plantation plots in Dambetenna Estates, Sri Lanka. Glyphosate residue analysis
was carried out using the Liquid Chromatography/ Tandem Mass Spectrometry (Triple
Quadruple) detection method after sample preparation was carried out using solvent
extraction methods. The results showed that glyphosate was detected in tea leaves of
glyphosate-applied plots. However, glyphosate was not detected in the tea leaves of the
glyphosate-free plots. Glyphosate was detected in soils of both glyphosate-applied and
glyphosate-free plots. The mean glyphosate concentration of soils in the glyphosateapplied
plot was 5.05 ± 1.09 mg/kg while the reading for soils in the glyphosate-free
plot was 2.93±0.14 mg/kg. Further, results revealed that the glyphosate concentration
of soils in the glyphosate-applied plot is significantly higher (p = 0.03) than in the
glyphosate-free plots. Glyphosate was applied in Dambatenna Tea Estate in accordance
with prescribed doses, and levels found in tea leaves were 0.5 mg/kg, which is below the
environmental protection agency’s suggested maximum permitted limits. Overall, these
findings suggest that the use of glyphosate in tea fields can lead to its accumulation in
tea soil and tea leaves.
