Spatial dispersion hot spots of contamination and human health risk assessments of PTEs in surface sediments of streams around porphyry copper mine, Iran.

This comprehensive research has been conducted to consider the distribution of PTEs in the surface sediments of a recently developed Dar-e-Allo copper mine in dependence on the potential ecological and human health risks. Field sampling was carried out discreetly at preselected sampling spots including the natural background, the streams around the mine, waste rock drainages, evaporative deposits, sediments containing Fe oxy-hydroxides and secondary phases. Distribution of target elements (Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, S, Sb, Se, and Zn) showed high levels of crustal elements. As regards, Fe, Al, and S are identified to exist as the most copious elements in the earth's crust, so have the major portion of potentially toxic elements (PTEs) in the sediment concentrations. Evaluating environmental indices reflected that in general, Cu, S, and Mo have a higher quota of contamination in sedimentary systems. the pollution load index (PLI), modified contamination degree (mCd), Contamination factor (Cf), Sediment potential index (SPI), Geo-accumulation index (Igeo) and Contamination degree (Cd) confirm that sedimentary systems of mining area are heavily contaminated by PTEs and were not found within the guideline acceptable values. The potential ecological risk index (PERI) displayed a high or severe risk level for Cu with a peak in green-blue sediments containing secondary minerals. The results of total carcinogenic risk (TCRs) show that As has high toxicity level and carries a risk of carcinogenicity among children and adults. The TCRs for Cd, Cr, Ni, and Pb with carcinogenic potential are found only in children and they are classified as the prime concern elements that have serious dangers to children's public health. The results of contamination source presumed that the sources of PTEs contamination were principally geogenic along with the anthropogenic sources in the study area. Therefore, the present study has highlighted the implication of human health risks of PTEs in sedimentary systems of copper mining, also will grant advice for prime stakeholders, including mine managers, Environmental Protection Agency, the government and public organizations in connection to protecting the environment, aquatic biota and consumer's health.

Ketogenic diets, physical activity and body composition: a review.

Obesity remains a serious relevant public health concern throughout the world despite related countermeasures being well understood (i.e. mainly physical activity and an adjusted diet). Among different nutritional approaches, there is a growing interest in ketogenic diets (KD) to manipulate body mass (BM) and to enhance fat mass loss. KD reduce the daily amount of carbohydrate intake drastically. This results in increased fatty acid utilisation, leading to an increase in blood ketone bodies (acetoacetate, 3-ß-hydroxybutyrate and acetone) and therefore metabolic ketosis. For many years, nutritional intervention studies have focused on reducing dietary fat with little or conflicting positive results over the long term. Moreover, current nutritional guidelines for athletes propose carbohydrate-based diets to augment muscular adaptations. This review discusses the physiological basis of KD and their effects on BM reduction and body composition improvements in sedentary individuals combined with different types of exercise (resistance training or endurance training) in individuals with obesity and athletes. Ultimately, we discuss the strengths and the weaknesses of these nutritional interventions together with precautionary measures that should be observed in both individuals with obesity and athletic populations. A literature search from 1921 to April 2021 using Medline, Google Scholar, PubMed, Web of Science, Scopus and Sportdiscus Databases was used to identify relevant studies. In summary, based on the current evidence, KD are an efficient method to reduce BM and body fat in both individuals with obesity and athletes. However, these positive impacts are mainly because of the appetite suppressive effects of KD, which can decrease daily energy intake. Therefore, KD do not have any superior benefits to non-KD in BM and body fat loss in individuals with obesity and athletic populations in an isoenergetic situation. In sedentary individuals with obesity, it seems that fat-free mass (FFM) changes appear to be as great, if not greater, than decreases following a low-fat diet. In terms of lean mass, it seems that following a KD can cause FFM loss in resistance-trained individuals. In contrast, the FFM-preserving effects of KD are more efficient in endurance-trained compared with resistance-trained individuals.