Banca de DEFESA: LARA LUIZA FREITAS DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LARA LUIZA FREITAS DE OLIVEIRA
DATE: 22/09/2023
TIME: 13:30
LOCAL: vídeo conferencia
TITLE:

EVALUATION OF POISONING AND ANTIMICROBIAL RESISTANCE INDUCED BY EXPOSURE TO HEAVY METALS ASSOCIATED WITH MINING ACTIVITIES

KEY WORDS:

Heavy metals; Water contamination; Genotoxicity; Antibiotic resistance

PAGES: 148
BIG AREA: Ciências Biológicas
AREA: Microbiologia
SUMMARY:

The mining activity stands out as one of the main sources of water contamination by heavy metals, especially after dam failures, such as the Fundão dam and Córrego do Feijão mine, which released ore tailings containing heavy metals into the basins. of the Doce and Paraopeba rivers, respectively. When metals are present in water as contaminants, they can cause human intoxication, as well as contribute to the development of antimicrobial resistance, since the mechanisms of resistance to metals and antimicrobials can be similar. This study investigated the toxic effects caused by heavy metals released after the rupture of the Fundão and Mina Córrego do Feijão dams, concerning cases of human intoxication and development of antimicrobial resistance. Initially, a documental study was carried out in the database of the Notifiable Diseases Information System in order to trace the epidemiological profile of metal intoxications in Minas Gerais and Brazil, before and after the dam failure. An increase of 5.3% / 23.3% of cases of metal intoxication was observed in Brazil and 34.7% / 34.3% in Minas Gerais after the rupture of the Fundão and Mina Córrego do Feijão dams, respectively. Subsequently, an integrative literature review was carried out to analyze studies that described the relationship between bacteria recovered from sites impacted by mining tailings resulting from the rupture of the aforementioned dams and the development of antimicrobial resistance. The searches were carried out in the PubMed, BVS, Science Direct and Web of Science databases, with six articles selected and, in general, all suggested that environmental contamination by heavy metals, resulting from mining waste released after disasters, favored the emergence of antimicrobial resistance genes. Additionally, metals were quantified in the water of the Itapecerica river, a polluted urban river, and multiresistant gram-negative bacteria (colistin, gentamicin and ciprofloxacin) were recovered from these samples and identified. The presence of iron, cobalt, lead, aluminum and mercury in the water was verified, the latter in concentrations above that allowed by law, and 13 multiresistant morphotypes were identified, all of them Enterobacterial (four Citrobacter amalonaticus; four Pantoea agglomerans; two Morganella morganii and three Escherichia coli). In the case of the E. coli bacteria, constantly present in the aquatic environment, it showed resistance to other antimicrobials, including beta-lactams. Finally, a study was carried out on the induction of resistance to meropenem by heavy metals at concentrations found in the water of the Doce river basin after the Fundão dam rupture, in E. coli. A multipass (21 days) in vitro resistance induction study was conducted using the multisensitive Escherichia coli ATCC 25922 bacteria, which was exposed to a metal mixture composed of iron (0.15 mg L-1), manganese ( 0.06 mg L-1) and cadmium (0.0002 mg L-1). Over the 21 days, an increase in the minimum inhibitory concentration against meropenem was observed, indicating the development and induction of resistance to this antimicrobial. Data from this study warn of toxic effects caused by heavy metals present as environmental contaminants after mining disasters to humans (intoxication) and microorganisms (antimicrobial resistance), which can lead to compromised public health.

BANKING MEMBERS:
Presidente - 2875448 - RALPH GRUPPI THOME
Externa ao Programa - 1080217 - FARAH MARIA DRUMOND CHEQUER BALDONI
Externo à Instituição - MAYRON ALVES DE VASCONCELOS - UECE
TAE - 1754438 - KARINA MARJORIE SILVA HERRERA