Epilithic biofilms, POCIS, and water samples as complementary sources of information for a more comprehensive view of aquatic contamination by pesticides and pharmaceuticals in southern Brazil.

Spatial-temporal monitoring of the presence of pesticides and pharmaceuticals in water requires rigor in the choice of matrix to be analyzed. The use of matrices, isolated or combined, may better represent the real state of contamination. In this sense, the present work contrasted the effectiveness of using epilithic biofilms with active water sampling and with a passive sampler-POCIS.

Presence of pharmaceuticals and bacterial resistance genes in river epilithic biofilms exposed to intense agricultural and urban pressure.

The continuous discharge of pharmaceutical compounds into the aquatic environment has raised concerns over the contamination of water resources. Urban activities and intensive animal breeding are important sources of contamination. The accumulation of antibiotics may lead to the transfer or alternatively maintain the presence of resistance genes in natural microbial communities existing in epilithic biofilms.