Quantificação de mercúrio em algas marinhas do estado do ceará por análise direta: Uma comparação sazonal

Abstract

Mercury (Hg) is a toxic heavy metal that can be present in the environment in many ways, including natural processes, industrial activities, mining, among others. In aquatic environments, Hg contamination has been a real nuisance in the modern world, as it affects both ecosystems and human health. Playing a vital role in the marine environment as primary producers, algal populations have been used to monitor the degree of pollution in an aquatic environment, they can accumulate heavy metals in their structures, affecting the health and development of beings at higher trophic levels, including humans. Thus, it is extremely important to analyze Hg, however, its analysis is a challenge because it is generally in low concentration in this type of matrix, requiring a sensitive analytical method for its detection. Keep track of your growth concentrations during different periods, in a given region, can also collaborate with the prevention of excessive contamination. Vapor atomic absorption spectrometry cold (CV AAS) and inductively coupled plasma mass spectrometry (ICP-MS) are the most common methods for Hg analysis, however, these techniques require sample preparation prior to analysis, implying greater sample manipulation, increasing the possibility of analytical errors, loss of analyte, in addition to demanding a longer analysis time. In this way, the direct analysis is a alternative to these techniques, as it dispenses with the sample preparation step, reduces the generation of hazardous waste, restricts the occurrence of analytical errors, presenting a shorter analysis time. The objective of this work was to determine Hg in samples of seaweed using decomposition amalgamation atomic absorption spectrometry (TDA-AAS) by the direct analysis method, making a comparison between the concentrations found and the local seasonality. Six species of algae (Bryothamnion Triquetum, Caulerpa Racemosa, Hypnea Musciformis, Sargassum Vulgare, Solieria Filiformes Ulva Lactuca) collected in different periods of the year (dry season and rainy season) were analyzed. The analysis method applied was U.S. EPA Method 7473, described elsewhere in the literature as a proven alternative to those techniques that require wet sample preparation. The highest concentration of Hg, in µg kg−1, presented in the work was in the seaweed Sargassum Vulgare, from 1479 ± 5, during the rainy season, while the lowest Hg concentration, in µg kg−1, in the study was for the seaweed Brytohamnion Triquetum, 68.6 ± 2.2, during the rainy season.