Abstract

Analysis campaign of underground water was done in 2010 on five boreholes water samples situated in agricultural cotton zone. The obtained results showed the presence of various active matters of at least 76 residues of pesticides, especially insecticides, herbicides and fungicides, with accumulated contents which could average 0.350 or 350 μg/L per borehole. Indeed, all the prospected boreholes were contaminated. Every molecules of pesticides analyzed were present with at least 1 μg/L, some molecules concentration such as: aldrine (7 ± 0.7 μg/L), dieldrin (2 ± 0.7 μg/Ls), phorate (7 ± 2 μg/L) and terbufos (7 ± 1 μg/L), highly exceeded maximum residue limits. The most affected zones of the contamination of the underground water by pesticides were those areas where the cotton faming is practiced.

Key words: Kérou, cotton farming, water of boreholes, pesticides