Heavy metal pollution of river freshwater environments currently raises significant concerns due to the toxic effects and the fact that heavy metal behavior is not fully understood. This study assessed the contamination level of eight heavy metals and trace elements (Cr, Ni, Cu, Zn, As, Pb, Cd, and Hg) in the surface sediments of 19 sites in 2018 during four periods (March, May, June, and October) in Olt River sediments. Multivariate statistical techniques were used, namely, one-way ANOVA, person product-moment correlation analysis, principal component analysis, hierarchical cluster analysis, and sediment quality indicators such as the contamination factor and pollution load index. The results demonstrated higher contents of Ni, Cu, Zn, As, Pb, Cd, and Hg, with values that were over 2.46, 4.40, 1.15, 8.28, 1.10, 1.53, and 3.71 times more, respectively, compared with the national quality standards for sediments. We observed a positive significant statistical correlation (p < 0.001) in March between elevation and Pb, Ni, Cu, Cr, and Zn and a negative correlation between Pb and elevation (p = 0.08). Intermetal associations were observed only in March, indicating a relationship with river discharge from spring. The PCA sustained mainly anthropogenic sources of heavy metals, which were also identified through correlation and cluster analyses. We noted significant differences between the Cr and Pb population means and variances (p < 0.001) for the data measured in March, May, June, and October. The contamination factor indicated that the pollution level of heavy metals was high and significant for As at 15 of the 19 sites. The pollution load index showed that over 89% of the sites were polluted by metals to various degrees during the four periods investigated. Our results improve the knowledge of anthropogenic versus natural origins of heavy metals in river surface sediments, which is extremely important in assessing environmental and human health risks and beneficial for decision-maker outcomes for national freshwater management plans.

Grapes are rich in phenolic compounds, being important for human health with anti-inflammatory, antiatherosclerotic, antimutagenic, anticarcinogenic, antibacterial, antiviral, and antimicrobial activity. The winemaking of the grapes generates significant amounts of waste. These wastes contain bioactive compounds in their biomass that can be used as a source of food improvement or as a source of nutrition supplementation. This study looks at the content of bioactive compounds, the polyphenolic profile, and the antioxidant activity in different white and red grape pomaces. The investigation of bioactive characteristics (total polyphenols, total flavonoids, catechins, tannins, and antioxidant activity) was carried out by UV-Vis spectrophotometric methods, while the individual polyphenolic composition was investigated by target and screening UHPLC-HRMS/MS analysis. Principal components (PCA) and the heat maps analysis allows the discrimination between the grape pomace resulted from white grape cultivars (Muscat Ottonel and Tamaioasa Romaneasca) and red grape pomaces (Cabernet Sauvignon, Merlot, Feteasca Neagra, Burgund Mare, Pinot Nore), with the identification of the specific phenolic compounds for each grape pomace type.