Determination and evaluation of the ecological risk of mercury in different granulometric fractions of sediments from a public supply river in Brazil.

This work reports the quantification of total mercury in sediments collected in periods with and without rain from the Joanes River, Bahia, Brazil. Determinations were made using Direct Mercury Analysis (DMA), the accuracy of which was confirmed with two certified reference materials. The highest total mercury concentrations were found at the sampling point close to commercial areas and large residential condominiums.

A risk assessment by metal contamination in a river used for public water supply.

Aquatic ecosystems provide habitats for many organisms. Historically, riverbanks have always been inhabited and exploited for subsistence and navigation. The present study evaluates the contamination and ecological risks caused by potentially toxic elements in surface sediments of the Paraguaçu River, Bahia, Brazil.

Assessment of toxicity of metals in river sediments for human supply: Distribution, evaluation of pollution and sources identification.

Ten surface sediments collected from Joanes River, Bahia, Brazil in rainy and drought periods in 2019 were evaluated according to the enrichment factor (EF), potential ecological risk index (RI), potential contamination index (PCI), pollution load index (PLI), and index of geoaccumulation (I). Initially the dry sediment was subjected to granulometric analysis and determination of the concentration of organic matter. Then, the samples were digested in HNO and analyzed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) to determine the metals cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb) and zinc (Zn).

In vitro photodynamic therapy against Foncecaea pedrosoi and Cladophialophora carrionii.

Photodynamic therapy (PDT) has been originally developed for cancer treatment, but recently, it has been successfully employed against microorganisms, including fungi. Chromoblastomycosis is a subcutaneous fungal infection that is recalcitrant to conventional antifungal drug therapy. The most frequent species involved are Foncecaea pedrosoi and Cladophialophora carrionii.