Abstract:
Organochlorine pesticides (OCPs) are synthetic pesticides widely used all over the world.
When present in the environment they adversely affect terrestrial and aquatic biodiversity.
Thus, there has been a continual demand to monitor the presence of OCPs within the
environment. The main objective of this study is to assess pesticide residues in coffee
processing effluent receiving stream and biota at Bore, Haro and Agaro, Jimma zone. Farther,
18 each of water, and 12 macro invertebrates samples were collected from the three sites
coffee effluent receiving streams. Extraction methods such as Dispersive Liquid-Liquid Micro
(DLLME) and Soxhlet Extraction were used for the analysis of pesticides from water and
macro invertebrates‟ sample, respectively. The samples were cleaned up with deactivated
silica gel and the final extracts were analyzed using Gas Chromatography with Electron
Capture Detector (GC-ECD). The coefficient of determination 9 pesticides showed linear
correlation (r2
> 0.99). The performances of the analytical procedures were evaluated using
percentage recovery and computed by spiking the blank samples with known concentration of
the target analytes. The finding shows, the percent recovery for each analytes were between
81.7% and 109.1% comply with routine analysis detection requirements. Analyzed pesticides
such as, Aldrin, g-chlordane, Dibuthylchlor, Endrin, Endosulfan sulfate, Dieldrin, p, p'- DDT,
Methoxychlor and chloradate were detected in the water and macro invertebrates (MI)
samples with varying concentration 89%, 58% and 37% of g-chlordane, Dibuthylchlor and
Aldrin, were detected with the highest mean concentration in MI and water sample at the
study area. The lowest detected pesticide was chloradate 0.002% in MI samples. In
conclusion, water and aquatic organisms are polluted by organochlorine pesticides and may
expose human, aquatic animals or general environment. Therefore, strict regulation is needed
in this particular study area as well as in Ethiopia in general.
