Título:	Distribuição de poluentes emergentes em amostras de água superficial e sedimento de fundo na bacia hidrográfica do Rio de Ondas, oeste da Bahia, Brasil
Autor(es):	Rego, Enoc Lima do
Orientador(es):	Souza, Jurandir Rodrigues de
Coorientador(es):	Silva, José Domingos Santos da
Assunto:	Pesticidas Sedimentos Commodities agrícolas Bacias hidrográficas - Ondas, Rio - Bahia (BA)
Data de publicação:	4-Jul-2022
Data de defesa:	31-Mar-2022
Referência:	REGO, Enoc Lima do. Distribuição de poluentes emergentes em amostras de água superficial e sedimento de fundo na bacia hidrográfica do Rio de Ondas, oeste da Bahia, Brasil. 2022. xix, 169 f., il. Tese (Doutorado em Química) — Universidade de Brasília, Brasília, 2022.
Abstract:	The Western Region of Bahia is known for the production of agricultural commodities, with the intensive use of fertilizers and pesticides. The presence of these chemical species and their residues in high concentrations can promote the emergence of deleterious effects on the environment and human health. With this scenario in mind, this work’s objective was to characterize the presence of emerging pollutants (pesticides, metals, and ions) in the water-bottom sediment system of the Rio de Ondas Watershed. Sampling was conducted on eighteen sites (P01-P17 e PB) along the basin in the dry and rainy seasons. In this work, liquid-liquid and liquid-solid extractions were developed for the extraction of pesticides in water and sediment, respectively. The methods’ validation was performed by the determination of figures of merit in univariate calibration, and the results fell within the recommended range by AOAC. The determination of analytes organophosphate pesticides, carbamates, pyrethroids, and strobilurin, in sediment samples, showed average concentrations ranging from 0.020 ng g -1 (Carbofuran) to 249.123 ng g-1 (Dimethoate) and from 0.029 ng g-1 ( Carbofuran and sulfotepe) to 533.522 ng g-1 (Dimethoate) in the dry and rainy seasons, respectively; in the method for the determination of organochlorine pesticides (OCPs), the averages ranged from 3.242 (P02) to 12.052 ng g-1 (P17) and from 0.313 (P14) to 30.861 ng g-1 (P13) in the dry and rainy seasons, respectively. In the water samples, the total concentrations of γ-HCH, Methoxychlor, Dementon-S, Methyl Parathion, Fenitrothion, Chlorpyrifos, and Azoxystrobin residues showed a significant difference, with higher OCPs levels in the rainy season. The assessment of the risk quotient for aquatic life, 59% (dry) and 76% (rainy), indicated a critical scenario for species protection. Regarding human consumption, elevated levels were observed for Heptachlor in the two sampling periods, and in the rainy season for Azoxystrobin, which reached levels that indicate risk in untreated water ingestion, mainly without treatment. In the study of the physicochemical parameters, metals, and ions, there was a statistically significant difference between seasons for Ca2+, PO4 2- , Al, Cu, and Zn, with higher medians in the rainy season; their concentrations, however, are within the potability standard. The study proved to be of categorical scientific relevance for the region, serving as an alert and as a database for future actions. In addition, there must be constant environmental monitoring in this and other basins in the region, with the investigation of a greater number of substances, promoting, from there, mitigating actions to reduce environmental and human risks.
Unidade Acadêmica:	Instituto de Química (IQ)
Informações adicionais:	Tese (doutorado) — Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2022.
Programa de pós-graduação:	Programa de Pós-Graduação em Química
Licença:	A concessão da licença deste item refere-se ao termo de autorização impresso assinado pelo autor com as seguintes condições: Na qualidade de titular dos direitos de autor da publicação, autorizo a Universidade de Brasília e o IBICT a disponibilizar por meio dos sites www.bce.unb.br, www.ibict.br, http://hercules.vtls.com/cgi-bin/ndltd/chameleon?lng=pt&skin=ndltd sem ressarcimento dos direitos autorais, de acordo com a Lei nº 9610/98, o texto integral da obra disponibilizada, conforme permissões assinaladas, para fins de leitura, impressão e/ou download, a título de divulgação da produção científica brasileira, a partir desta data.
Agência financiadora:	Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).
Aparece nas coleções:	Teses, dissertações e produtos pós-doutorado

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