Determinação de cafeína, hormônios esteroidais e esteróis em corpos hídricos da cidade de Manaus

Abstract

The Amazon region is coveted worldwide, as it has great water potential, being a region studied mainly in the environmental area. In the center of this geographic region, the city of Manaus (capital of Amazonas) is located. The igarapés (watercourses) that cross the city are highly subject to the disposal of domestic sewage, industrial effluents and garbage, in which a series of chemical compounds are found, many of which are considered chemical markers. Caffeine, anthropogenic sterols and hormones are included in this class. Caffeine and hormones are considered urban chemical markers. Sterols, on the other hand, can be of natural or anthropogenic origin and are considered as biomarkers. In this context, this project aimed at the quantitative determination through the LC-MS/MS technique of caffeine, hormones (estrone, estradiol, estriol, 17α-ethinyl estradiol and progesterone) and sterols (cholesterol, epicoprostanol, coprostanol, cholestanol, brassicasterol, ergosterol, campesterol, β-sitosterol, stigmasterol and stigmastanol) in 36 water samples from streams of the main watersheds of Manaus and Rio Negro, in order to evaluate the agreement between different chemical indicators of anthropogenic pollution in Amazonian water bodies. This study presents samples collected from streams of the Adolpho Ducke Forest Reserve (preserved area), samples from the Tarumã-Açu stream (peri-urban area), samples from the Quarenta and Mindu streams (urban areas), and the Rio Negro (peri-urban area). Caffeine and hormones were determined in dissolved organic matter (MOD) and sterols in particulate organic matter (MOP). The results of this work show that the creeks of the Adolpho Ducke Reserve and Tarumã-Açu presented similarities regarding the aspect of greater contribution of organic matter of natural origin (terrestrial and aquatic plants) and in the concentrations of anthropogenic markers, however they differ in their aspect of the collection area and volume of water. An accentuated contamination by untreated domestic sewage was also observed in the Mindu and Quarenta streams, with greater contributions of organic matter of anthropic origin, and a light to moderate contamination in areas of confluence with the Rio Negro.