The Northeast of Yucatan Peninsula; Mexico; due to its natural resources: beaches, jungles, sinkholes, reef is one of the main Mexican touristic poles. Presenting one of the most accelerated growth is recreational activities and in consequence the rise of development on the coast and inland. Moreover, this region underlies a vulnerable karstic coastal aquifer at the Yucatan Peninsula, high permeability fractured limestone, which allows rapid transport of contamination resulting in a significant potential increase of pollution affecting the ecosystems.
Several studies indicate the importance of chemical markers to track pollution by domestic and industrial activities. Potential candidates are endogenous metabolites released by the human body and components of pharmaceutical products, personal care products and food. Regular and constant consumption is a prerequisite for the selection of a good marker, which implies that consumer habits do not change or change gradually in the coming years. Caffeine has been used as a chemical marker of the water quality to improve the accuracy with which are detected polluting sources of domestic origin. Caffeine occurs mainly in beverages such as coffee, tea, some bottled drinks (sodas) and some drugs for human consumption.
This work summarize three evaluations of caffeine along with bacteriological quality and the toxicity to the ecosystem. Caffeine was used as an emerging contaminant as a marker to identify the sources of pollution and its impact on groundwater (wells, sinkholes and lagoon). The detection of caffeine to points of high presence of bacteria E. coli, can confirm that the alteration of the water quality in some of these sites has a direct connection with the tourist type anthropogenic activities. While the presence in the area of extraction wells is due to infiltration of untreated or semitreated wastewater water, moreover presence of caffeine was also detected at the lagoon where only rural and domestic activities characterize the area, the toxicity evaluation by zooplankton indicated an impact in the aquatic biota.
The importance of these results indicated that presence of contaminants might not be related to the increase or the size of the human developments but the lack of wastewater service that represent a potential impact to the aquatic ecosystems.