Desenvolvimento de sistema FI-CVG-ICP-MS para determinação de mercúrio em peixe

Abstract

Mercury (Hg) is a toxic element that can accumulate in the environment and in the food chain due to its biomagnification and bioaccumulation. A high concentration of Hg in the human body can lead to health complications, compromising mainly the nervous system and the functioning of some organs. One of the forms of contamination by Hg is from the ingestion of contaminated food. Several studies report the contamination of the Madeira River, located in Porto Velho - Rondônia, by Hg that is used in gold mining. It should be noted that there is a considerable population of riverine people who use the river for fishing. The consumption of contaminated fish can be a public health issue, justifying the development of analytical methods to monitor Hg concentration levels in fish. In this sense, a sample introduction system with chemical vapor generation coupled to inductively coupled plasma mass spectrometry was developed for Hg determination in fish muscle. The reaction conditions and physical variables of the proposed system were evaluated and eighteen species of fish with different eating habits were analyzed, such as piscivores, scavengers, carnivores, omnivores and herbivores. The results were analyzed in accordance with current legislation in Brazil (ANVISA), which specifies maximum Hg values of 1.0 g g-1 for predatory species and 0.5 g g-1 for non-predatory species. The accuracy of the proposed method was evaluated using certified reference material Dogfish Liver Certified Reference Material for Trace Metals (DOLT-4) where an agreement of 95% (t-test) with certified value was achieved. The precision of the method is better than 5% (relative standard deviation) for ten consecutive measurements of Hg. The method detection and quantification limits were 0.04 ug g-1 and 0.06 ug g-1, respectively, which meets the maximum concentration of Hg in fish established by ANVISA.