Navegando por Assunto "Heavy metals"

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Acesso aberto (Open Access)
Avaliação da presença de metais pesados na água potável fornecida à população urbana de Altamira e o seu possível impacto epidemiológico sobre doenças crônicas renais
(Universidade Federal do Pará, 2024-04-30) STORCH, Wesley; FAIAL, Kleber R. Freitas; http://lattes.cnpq.br/0166366420811929; HTTPS://ORCID.ORG/0000-0002-8575-1262; PEREIRA, Adenilson Leão; http://lattes.cnpq.br/3184636120604556
The Xingu River is crucial for potable water supply in Altamira, but it faces risks of heavy metal pollution, especially mercury, due to illegal mining and UHBM activities. Mercury can bioaccumulate in humans and be associated with an increased risk of hypertension and kidney diseases. This study evaluated the presence of heavy metals in Altamira's drinking water and outlined the epidemiological profile of chronic kidney disease (CKD) in Altamira and the Xingu region. Concentrations of Al, As, Cr, Cd, Pb, Fe, and Hg were measured in 24 water samples collected in July 2022, using ICP/MS by the Evandro Chagas Institute, compared to Brazilian legislation and WHO limits. Mortality data from CKD, diabetes mellitus (DM), and systemic arterial hypertension (SAH) from 2000 to 2020 were analyzed using public data from DATASUS. Additionally, medical records of CKD patients treated at HRPT from 2007 to 2023 were analyzed. The concentrations of metals in the analyzed water samples were within established limits, except for aluminum (Al), which was elevated in two water samples. Mortality data obtained from DATASUS between 2000 and 2020 showed a significant increase in mortality due to SAH in Altamira (R²=0.80), while mortality from CKD (R²=0.30) and DM (R²=0.31) had a smaller impact on the mortality rate during the studied period. Considering the medical records of CKD patients treated at HRPT, it was identified that between 2007 and 2023, 174 CKD patients treated at HRPT were from Altamira, with 64.4% men and 35.6% women. Regarding age, 48.85% were over 60 years old, and 36.78% were between 41 and 60 years old. The main comorbidity associated with CKD was SAH (56.90%), followed by the association of SAH and DM (36.94%). Altamira presented an average prevalence of 8.99 cases per 100,000 inhabitants and an average incidence of 10.24 new cases per year of CKD during the analyzed period. In the Xingu region, 403 CKD cases were identified, predominantly in men (61.5%) with an average age of 60 years. The main comorbidity associated with CKD was SAH (49.88%), followed by the association of SAH and DM (37.47%). The average prevalence of CKD in the region was 6.97 cases per 100,000 inhabitants, with an average incidence of 23.70 new cases per year of CKD during the analyzed period. The levels of metals in the analyzed water samples are within the limits recommended by Brazilian legislation and WHO. The high prevalence of CKD in Altamira and the Xingu region raises concerns about public health impacts. Historical mercury contamination may be related to the high mortality from SAH and the prevalence of CKD associated with SAH. These results emphasize the need for continuous monitoring of water quality and public policies to mitigate the impacts of CKD in the region.
Acesso aberto (Open Access)
Avaliação de risco ambiental por contaminação metálica e material orgânico em sedimentos da bacia do Rio Aurá, Região Metropolitana de Belém - PA
(Instituto Nacional de Pesquisas da Amazônia, 2013-03) SIQUEIRA, Gilmar Wanzeller; APRILE, Fábio Marques
The Aurá River basin is situated in the Belém Metropolitan region, between the municipalities of Belém and Ananindeua, where the rate of population growth has increased without any social and environmental control. The region is intensely exploited and the more frequent environmental problems are deforestation, erosion, flooding, water pollution and contamination, especially by heavy metals and organic compounds (OC). Geochemistry behavior (Al, Fe, Mn, Cr, Ni and Cu) and OC levels were determined in the 30 sampling sites between 2008 and 2010 in the bottom sediments of the river. There is an uncontrolled sanitary landfill situated at the north of the Aurá River responsible, in part, by the metallic contamination of the sediments. The environmental stress is classic in the region, and it has resulted from anthropic activities, which has transported unconsolidated material associated to metals to the Aurá. The variables studied were classified on the transport mechanisms and sources (allochthonous and/or autochthonous). The results showed that the main contribution of ions Al and Fe was the sanitary landfill; Mn and Ni was the adjacent soils; Cr was modified (III/VI) by the allobiochemistry, and Cu by bio-induced processes.
Acesso aberto (Open Access)
Remoção de Ni2+ de soluções aquosas utilizando o talo do cacho do açaí (Euterpe oleracea) como Biossorvente
(Universidade Federal do Pará, 2021-06-30) GESTER, Nayara Matos Lima; SIQUEIRA, Joana Luíza Pires; http://lattes.cnpq.br/4650162959340860
This work used as biosorbent the stem of the açaí bunch (Euterpe oleracea) – TCA – in natura for phytoremediation of the heavy metal Ni2+ from synthetic solutions. The material was characterized using Fourier Transform (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) techniques. The result of the infrared analysis revealed the presence of hydroxylic and carboxylic functional main groups fundamental in the biosorption process. The SEM analysis showed a material with a rough and porous structure with a visible variety of pore sizes and the EDS semi-quantitatively detected the presence of elements such as C, O and Ca, characteristic of lignocellulosic materials, in addition to the presence of Ni2+ after the process of adsorption. The adsorption behavior of Ni2+ ion in aqueous solution by the açaí bunch stem (ACT) was carried out in batch and investigated influences such as concentration, dosage, granulometry, contact time and pH. At a concentration of 25 mg.L-1 and pH between 6 and 7 TCA showed removal efficiency above 80%. Langmuir, Freundlich and Dubinin-Radushkevich models were applied to describe the equilibrium isotherms using linear regression analysis. The adsorption kinetic mechanism was better represented by the pseudo-second order kinetics. Monolayer adsorption according to the Langmuir model better described the biosorption process in TCA with a correlation coefficient (R2) close to 1 and a maximum adsorption capacity of 8.62 mg.g-1. The process kinetics showed a better fit to the pseudo-second order model, indicating chemisorption, with R2 close to 1, adsorption capacity (qe) = 6.60 mg.g-1 and adsorption rate constant (K2) = 0.082 g.mg-1.min-1. The TCA in natura presented satisfactory results for the treatment of wastewater, a fact that reinforces its environmental proposal.