Banca de DEFESA: LARISSA NAYARA LIMA SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : LARISSA NAYARA LIMA SILVA
DATA : 18/10/2024
HORA: 14:00
LOCAL: CELBE e de forma remota
TÍTULO:

Mercury in Fish Farms: Impacts and Behavioral Responses

PALAVRAS-CHAVES:

Aquatic Contamination.

Bioaccumulation.

Ecotoxicology.

Environmental Monitoring.

Food Safety.

PÁGINAS: 90
GRANDE ÁREA: Outra
ÁREA: Ciências Ambientais
RESUMO:

Mercury contamination in fish farms is concerning due to its toxicity and the risks it poses to human health and ecosystems. Mercury accumulates in water, organisms, and sediments, causing metabolic blockages, reproductive alterations, and reduced fish populations. Given the severity of these impacts, it is essential to investigate the distribution of this metal to understand the risks and guide sustainable fish farming practices. The objective of this study was to investigate the presence and effects of mercury in fish farms, both from an international and regional perspective, and to analyze the behavioral responses of fish exposed to different levels of mercury contamination. Initially, a systematic review and meta-analysis of mercury concentrations in farmed fish worldwide were conducted by searching the ScienceDirect, SciElo, LILACS, PubMed, and Scopus databases. Of 398 articles found, 22 were accepted for data extraction. Additionally, mercury concentrations were analyzed in 12 fish farms in the State of Mato Grosso, Brazil. Samples of sediments, soil, and vegetation were collected from the fish farming tanks and adjacent areas (approximately 15 meters from the tanks). Muscle, brain, liver, and fin tissues were also collected from the fish. An in vivo behavioral experiment was conducted to evaluate the responses of fish exposed to different mercury concentrations in controlled environments, using multi-compartment linear and random choice systems, with three control compartments, three compartments with a low concentration of 0.5 mg/kg (the maximum limit accepted by ANVISA's RDC Resolution No. 42/2013), three compartments with a medium concentration of 2.5 mg/kg (5 times higher than ANVISA's established limit), and three compartments with a high concentration of 5 mg/kg (10 times higher than the ANVISA limit). The results showed regional differences in mercury contamination in farmed fish. The African continent stood out with high concentrations, especially associated with illegal fish farming practices. The fish Hoplias lacerdae, Oreochromis niloticus, and Pseudoplatystoma corruscans had the highest mercury concentrations (1300±0 µg/kg, 912.72±1595.17 µg/kg, and 630±0 µg/kg, respectively), suggesting a strong influence of dietary habits and local environmental conditions. Mercury concentrations in fish farms in the State of Mato Grosso were below the limits set by Brazilian legislation, but we emphasize the importance of continuous monitoring due to the persistent toxicity of mercury and its potential long-term impact on human and environmental health.In the behavioral analysis experiment, fish showed a preference for compartments with lower mercury concentrations (control and ANVISA-determined concentration). This avoidance behavior suggests the ability of fish to detect and avoid more contaminated areas, which has important implications for understanding the ecological impacts of mercury contamination and for managing fish farms. Implementing effective monitoring and regulatory measures is important to mitigate the risks associated with mercury contamination and to ensure food safety and environmental preservation.

MEMBROS DA BANCA:
Presidente - 83200001 - AUREA REGINA ALVES IGNACIO
Interna - 181.924.407-53 - SANDRA DE SOUZA HACON - Fiocruz - RJ
Interno - 118181008 - WILKINSON LOPES LAZARO
Externa à Instituição - IVANISE MARIA RIZZATTI - UFRR
Externa à Instituição - MARTA LOPES ALONSO - USC