Biological treatment of pesticide-containing wastewater from coffee crops: selection and optimization of a biomixture and biobed design.

The biopurification systems (BPS) or biobeds are employed for the treatment of pesticide-containing wastewater of agricultural origin. The use of these devices for pesticide removal requires the proper optimization of the composition of biomixtures (BPS active matrix) according to the target pesticides applied on a specific crop and the available materials used in their elaboration. This work aims to design a biomixture for the simultaneous treatment of several pesticides applied in coffee crops, according to local practices in Costa Rica.

An integrative water quality evaluation in two surface water bodies from a tropical agricultural region in Cartago, Costa Rica.

A monitoring study was carried out in two micro-catchments in the Reventazón basin, in Northern Cartago, Costa Rica; pesticide occurrence and water quality were analyzed. Twelve pesticides were detected, five insecticides (chlorpyrifos, carbofuran, cypermethrin, imidacloprid, and oxamyl), four fungicides (carbendazim, imazalil, metalaxyl, and thiabendazole), and three herbicides (diuron, linuron, and terbutryn); eight of them presented risk quotients RQ >1, which implies a high risk for the environment. The water quality evaluation included fourteen physicochemical and microbiological parameters, out of which thermotolerant coliforms, nitrate, and total phosphorus exceeded a selected threshold value in every sample.

Pesticide occurrence and water quality assessment from an agriculturally influenced Latin-American tropical region.

A monitoring study was carried out in three agriculturally influenced microcatchments in Costa Rica during 2012-2014, for pesticides and water quality parameters. A total of 42 pesticides were analyzed, detecting the following in water samples: two herbicides (oxyfluorfen, diuron), four insecticides (carbofuran, chlorpyrifos, oxamyl, ethion), and two fungicides (thiabendazole, carbendazim); while in sediment samples only the insecticides, chlorpyrifos and cypermethrin were found. Water quality was also assessed by the Canadian Council of Ministers of the Environment Water Quality Index and the National Sanitation Water Quality Index, the first one classified most of the sampling point as marginal and poor quality while the second one classified most of them as good quality, the most affected parameters were nitrate, phosphorous, suspended solids and organic matter content.