Search results for "heavy metals."

Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses

2011

The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for (137)Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil a…

Influence of Temperature on Characteristics of Particulate Matter and Ecological Risk Assessment of Heavy Metals during Sewage Sludge Pyrolysis

2021

The formation process of Particulate Matter (PM) during sludge pyrolysis at different temperatures (300–700 °C) and the ecological risks of heavy metals were studied. The results showed that the particulate matter is mainly condensed on the quartz film in a carbon-based organic matter when the pyrolysis temperature was between 200–500 °C in a volatilization process. Inorganic particles was found in the particulate matter when the temperature was raised to 500–700 °C in a decomposition stage. Heavy metals were enriched in particulate matter with increase in pyrolysis temperature. When the temperature reached 700 °C, the concentration of Pb and Cd in the particulate matter significantly incre…

Suspended particulate matter fluxes along with their associated metals, organic matter and carbonates in a coastal Mediterranean area affected by min…

2016

International audience; A study of suspended particulate matter (SPM) fluxes along with their associated metals, organic matter and carbonates, was conducted off the Mejerda River outlet in May 2011 and in March and July 2012 at depths of 10, 20 and 40 m using sediment traps. SPM fluxes are more significant near the Mejerda outlet, especially in winter, but dissipate further offshore. Normalization reveals that the Mejerda is a major source of Pb, Zn, Cd, Cu, Ni, and Co, all of which are the result of human activities. In contrast, Fe, Mn and N are of authigenic origin. The enrichment factor shows that Pb, Zn and especially Cd are the most highly polluting metals off the Mejerda outlet. Thi…

Hydroponic Lettuce Cultivation Using Organic Nutrient Solution from Aerobic Digested Aquacultural Sludge

2021

The aim of this study was to demonstrate how aquacultural sludge can be processed and utilized as an organic nutrient solution (ONS) for hydroponic lettuce production. By using a previous developed method, approximately 80% of the processed sludge was reclaimed as a clear, nutrient-rich solution. The performance of the recovered nutrient solution on lettuce growth was assessed in a nutrient film hydroponic system. The results were compared to the results obtained using a conventional nutrient solution (CNS). Yield, fresh weight, water consumption, and nutrient and heavy metal content in leaf tissue were measured. In spite of a 16% lower average fresh weight obtained in ONS compared to the w…

Lead concentrations in feathers and blood of common blackbirds (Turdus merula) and in earthworms inhabiting unpolluted and moderately polluted urban …

2006

9 pages; International audience; Despite the dramatic decrease of atmospheric lead (Pb) concentrations in urban areas of most industrialised countries, we hypothesised that urban common blackbirds (Turdus merula) may still be contaminated by Pb concentrations of toxicological concern due to transfer from soil through the food chain. We sampled blackbirds and earthworms, one of their main preys, in Besan?, a middle-size city of Eastern France (where atmospheric Pb concentrations decreased from 0.5 microg/m(3) in 1987 to nearly 0 in 2002) and in a rural reference site. Lead concentrations were determined in the tissues of the different functional groups of earthworms (anecic, epigeous and end…

Begleitende Inhaltsstoffe in 22 OTC-Fischöl- und Lebertranpräparaten: Cholesterin, Schwermetalle und Vitamin A

1989

Fischolkapseln werden von selbstmedizierenden Patienten in zunehmendem Mase eingenommen. Hier wurde der Frage nachgegangen, ob 22 kommerziell erhaltliche Fischol- und Lebertranzubereitungen Begleitsubstanzen enthalten, deren Menge unter Umstanden nachteilig fur den Patienten sein konnten. Gemessen wurden: Cholesterin mit der Gaschromatographie, Schwermetalle mittels Atomabsorption und Vitamin A mit der hochauflosenden Flussigkeitschromatographie (HPLC). Sowohl der Cholesterin-als auch der Schwermetallgehalt lagen in unbedenklichen Bereichen. Der Vitamin-A-Gehalt von Lebertrankapseln wurde jedoch in Mengen gefunden, bei denen schwangere Frauen die Dosierungsempfehlungen der Hersteller nicht …

The comparative research of leaching tests and the sequential chemical extraction based on the environmental risk assessment by a selected type of wa…

2020

The problem of the circulation of metal ions in the environment remains a current problem in view of the quality of received agricultural crops. The necessity of increasingly frequent use of alternative sources of biogenesis in the form of waste substances poses a threat of bringing significant amounts of heavy metals harmful to human health and life to soils. The article discusses a significant problem, which is the comparison of the results of the environmental impact assessment of waste obtained based on the implementation of legitimate leaching tests (the three-stage leachability test according to PN-Z-15009) with the results obtained from sequential chemical extraction tests according …

Heavy metals analysis by non invasive techniques for fish food quality control

2014

Mercury in fish products: what’s the best for consumers between bluefin tuna and yellowfin tuna?

2017

A total of 205 bluefin and yellowfin tuna samples were examined for mercury detection in order to verify possible differences and have a detailed risk assessment of the two tuna species. The results showed significant higher mercury concentration in muscle tissue of bluefin tuna respect yellowfin tuna (p < 0.001) with mean concentration of 0.84 mg/kg and maximum value of 1.94 mg/kg. These differences can be due the different biological and ecological aspects of the two tuna species and to different oceanographic aspects between Atlantic Ocean and Mediterranean sea. The results obtained in this study suggest an advisable containment of the sources of pollution and further studies on the c…

The use of mosses in biomonitoring of selected areas In Poland and Spitsbergen in the years From 1975 to 2014

2015

Przeanalizowano historyczne zmiany stężeń metali ciężkich: Mn, Ni, Cu, Zn, Cd i Pb zakumulowanych w próbkach mchów pobieranych do badań w Polsce, na terenach leśnych Beskidów i Karkonoszy oraz w lasach północno-wschodniej części kraju, w odniesieniu do mało zanieczyszczonych obszarów Archipelagu Svalbard, którego największą wyspą jest Spitsbergen. Wyniki badań przedstawianych w literaturze uzupełniono wynikami badań własnych, prowadzonych w 2014 r. Wykazano, że spośród wymienionych obszary Beskidów oraz Karkonoszy były i są najbardziej narażone na depozycję metali ciężkich. Stwierdzono również, że na przestrzeni lat 1975-2014 nastąpiło znaczące zmniejszenie stężeń Cu, Zn, Cd i Pb w mchach p…