PRESENCE OF CAFFEINE IN THE KARST LAKE PUNTA LAGUNA OF THE YUCATÁN PENINSULA AND ITS ENVIRONMENTAL RISK

Abstract

Caffeine is known to be a chemical indicator of anthropogenic contamination in water bodies because it is highly soluble and persistent. As such, caffeine is an excellent water quality marker and tool in environmental impact assessments. Our goal was to quantify the caffeine in water from the Yucatán karstic groundwater and determine its environmental impact on indigenous aquatic biota. High-performance liquid chromatography (HPLC) with diode-array detection was used to quantify the caffeine content in water. Acute toxicity tests were performed in six zooplankton rotifer-and ostracod-strain groups native to the Yucatán peninsula that were cultured in our laboratory. In addition, the risk posed by caffeine in water on aquatic biota was determined, using risk assessment of the environmental concentration of caffeine in water (MEC) and the predictive values of toxicity (PNEC) obtained from our acute toxicity study. High concentrations of caffeine were found in the water. The most sensitive species to caffeine exposure was Diaphanocypris meridiana (ostracod), with an LC50 value of 288.383 mg/L, and the most tolerant organism was Lecane cornuta (rotifer) with an LC50 value of 3694.611 mg/L. Caffeine contamination of groundwater into aquatic ecosystems suggested, could have others active pharmaceuticals, hazardous substances, and personal care products. The presence of caffeine in Punta Laguna ranges between 1.79 and 3.93 mg/L, which represents a low to moderate risk for rotifers and a high risk for ostracods.