Abstract:
Copper‐based fungicides are extensively used in the control of coffee pests and
diseases because they are relatively cheap and effective. This practice presents
serious environmental implications owing to the toxic nature of copper. We report
here an assessment on the effects of the use of copper‐based fungicides on River
Kamiti, which flows along coffee growing areas of Kiambu District, Kenya. The levels
of copper in the river were determined using flame atomic absorption
spectrophotometry (FAAS) and were found to range from 0.3 to 2.38 x 10‐2mgL‐1
. It
was observed that high levels of copper coincided with coffee spraying seasons and
a high amount rainfall, indicating that these contributed to increased seepage of
copper in the river. Active pulping factories on both sides of the geographicalregions
were also found to be a source of the same. Statistical analysis on the experimental
data of copper levels from the study sites showed that there was no significant
difference between the regionsimplying that the sampling sites were not the source
of variation. Although there is clear evidence that coffee farming introduces copper
into the river, the levels of copper in Kamiti river were found to be within acceptable
limits and this would be attributed to dilution effects. However, at specific points,
the levels of copper were very high threatening the survival of aquatic animals, thus
the use of copper compounds is of environmental concern.
