In a report issued Monday, the Institute for Environmental Protection and Research said traces of pesticide contamination were found in 55.1 percent of 1,297 samples of surface water and 28.2 percent of 2,324 samples of groundwater in 2010.
Using data provided by regional authorities, the institute identified a total of 166 types of pesticides, up from the 118 found two years earlier, Italian news agency ANSA reported.
Researchers said the highest levels of pesticides were found in the Po River Valley in northeast Italy.
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