TITLE:
Use of Caffeine for the Evaluation of the Anthropic Influence over the Upper and Middle Iguaçu River Basins
AUTHORS:
Bruna Scipioni, Márcia Cristiane Kravetz Andrade, Luis Otávio Miranda Peixoto, Alinne Mizukawa, Tais Cristina Filippe, Júlio César Rodrigues De Azevedo
KEYWORDS:
Water Resources, Water Quality, Caffeine, Urban Areas
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.14 No.3,
March
23,
2022
ABSTRACT: Many parameters are usually used as gauges to describe water quality worldwide, such as the concentrations of phosphorus, forms of nitrogen, dissolved oxygen (DO), among others. Though legislative limits for the concentrations of these substances are in place, such is not the case for caffeine. Caffeine is a pharmacologically active alkaloid, from the xanthine group, which can be used as a chemical tracer for anthropic influence over water resources. The objective of this study was to analyze the pollution indicators over the Igua?u River, one of the main rivers in Southern Brazil, through the examination of nutrients, DO and their correlations to caffeine. The water samples were collected from 10 sampling sites along the river course, unevenly spaced to better represent the different environmental scenarios present in its basin, extracted from 2014 to 2017. Caffeine was detected and quantified through high-efficiency liquid state chromatography. Results show that both nutrient and caffeine concentrations increased in intensely urbanized areas, specially from IG2 to IG5 sampling sites. Downstream from IG6 the contaminant concentrations decreased mainly due to higher river flows and lower population density. Caffeine was detected in 82% of the samples, indicating that most of the sampling sites were under anthropic influence.