Occurrence and risk assessment of pharmaceuticals in irrigation water and lettuce crops in Colombia

Abstract

This study presents the first detailed investigation into the occurrence and risk of pharmaceutically active compounds in irrigation water and lettuce crops within the critical agricultural region of Sabana de Bogotá, Cundinamarca, Colombia. Systematically were analyzed eight pharmaceutically active compounds (PhACs)—including an antiepileptic drug, five antibiotics, one antihypertensive, and one anti-inflammatory—across six farms along the Bogotá River using liquid chromatography-tandem mass spectrometry.

The findings reveal a widespread presence of PhACs in irrigation water, with Farm C-Principal exhibiting the highest detection frequency (97 %) and M-La Victoria showing the highest total concentration (613 ng/L). Clarithromycin and ciprofloxacin were the most concentrated among consistently detected PhACs.

Principal Component Analysis was used to reduce the dataset's dimensionality and identify correlations among the variables. The study also estimated PhACs loading rates into lettuce crops using average water concentrations and CropWat software, with estimated inputs ranging from 5.2 to 26.3 g/ha per crop cycle. Crucially, several PhACs were detected in lettuce, with diclofenac (up to 70.9 ng/g) and trimethoprim (up to 61.6 ng/g) being the most frequently observed. While ecological risk assessment indicated a high risk from pharmaceuticals in irrigation water, particularly clarithromycin, trimethoprim, and diclofenac, the human health risk from consuming the irrigated lettuce appeared negligible. This research provides critical baseline data on PhACs contamination in the Sabana de Bogotá region, which is essential for informing future research and developing effective mitigation strategies.