Search results for "accumulation"

ASSESSING MERCURY POLLUTION USING BLACK STORK EGGSHELLS

2021

Female birds whose bodies contain environmental contaminants produce eggs with shells that are likewise contaminated, making bird eggshells appropriate indicators for monitoring environmental toxins. Common contaminants include organic mercury compounds, especially methylmercury, which are known to bioaccumulate and biomagnify in the food chain. Black storks (Ciconia nigra) predominantly consume fish and are thus at risk for high mercury intake. In this study, we used eggshells of black storks as a proxy to reconstruct the concentration levels and distribution of mercury, a well-known toxic element, in various parts of Latvia. Preliminary analyses have shown that deposition levels of mercur…

Growth and convergence profiles in the Spanish provinces (1965-1997)

2005

.  Economic performance in Spanish provinces has led to a considerable improvement in standard of living of their populations. Intense capital accumulation since the 1950s played a key roll in this process. Provincial inequalities may increase or decrease as a result of this growth pattern. This study analyzes the evolution of the disparities by means of distribution dynamics techniques. It explicitly considers economic size of each province and whether spatial spillovers exist. Results indicate that the convergence process has been especially intense for labor productivity, total factor productivity, and capital intensity, while for per capita income the patterns of convergence are less ma…

The pathophysiology of acute heart failure: the key role of fluid accumulation

2008

Relationships between sediment physico-chemical characteristics and heavy metal bioaccumulation in Mediterranean soft-bottom macrophytes

2001

Abstract Concentrations of Hg, Cd, Pb and Zn in the two seagrasses ( Posidonia oceanica and Cymodocea nodosa ), green alga Caulerpa prolifera and sediment and some physico-chemical characteristics of the sediment (organic matter, fine fraction (particles Significant correlations between the concentrations of metals in the plants and sediment (alone or normalized with respect to the physico-chemical characteristics) were usually found for Hg and Zn. For Pb only C . prolifera fractions were correlated to the Pb content of the sediment. For Cd no significant correlations were obtained between the metal in the plants and sediment. The concentration factors of the metals in the plants with respe…

Control of end-of-life oxygen-containing groups accumulation in biopolyesters through introduction of crosslinked polysaccharide particles

2021

The formulation of bio-based materials with good performance in service and controlled end-of-life is imperative for an effective circular economy. In this work, an innovative approach to induce and control the end-of-life of biodegradable polyesters through introduction of crosslinked polysaccharide particles is proposed. Chitosan (Ch) has been subjected to ionotropically crosslinking and then added to polylactic acid (PLA) at different amounts (1.0–4.0%w) by melt mixing. All obtained results suggest that the addition of crosslinked Ch (cCh) particles does not modify significantly the investigated biopolyester properties. Specifically, the thermal analysis of the composites reveals that th…

Long-term Effects of Bioaccumulation in Ecosystems

2005

Extensive damage to organisms and declines in wildlife populations have been observed together with long-term bioaccumulation and biomagnification of persistent xenobiotic chemicals. Heavy metals, especially organic or biomethylated mercury, lead, cadmium and organic tin compounds have caused environmental damage through bioaccumulation on a local scale. Effects on wildife caused by bioaccumulation of persistent organochlorine compounds are more widespread. However, the causal relationship between a biomagnified compound and the long-term effects have been established in only a few cases. Metabolic transformations, and occurrence of several toxic contaminants together in many cases, complic…

The effect of ash and compost on the content and bioaccumulation of selected heavy metals

2019

Abstract Therefore the carried out study aimed at determination of the effect of high-calcium brown coal ash and compost being produced from municipal sewage sludge on the content and bioaccumulation of heavy metals in potato tubers, wheat grains and rapeseeds during a three-year period. Rapeseeds contained most Cd whereas wheat rains less. Potato tubers, wheat grains and rapeseeds contained more Mn, Ni and Zn in the fertilization objects with municipal sewage sludge with or without coal ash and compared to those where calcium carbonate or coal ash had been introduced into the soil at a dose corresponding to 1.5 Mg CaO · ha–1 at the beginning of this study. Differences in the Mn, Ni and Zn …

Emerging pollutants in the aquatic environment: Assessment in biota and influence of microplastics

2021

El medio ambiente sufre el vertido continuo de contaminantes antropogénicos, incluyendo compuestos orgánicos, como fármacos y productos de cuidado personal (PPCPs), plaguicidas, sustancias perfluoroalquiladas (PFASs), drogas de abuso y microplásticos. Algunos de estos contaminantes son de hecho considerados contaminantes emergentes. Una de las principales fuentes de contaminantes al medio ambiente son las estaciones depuradoras de aguas residuales Además, existen otras fuentes de carácter más difuso como la infiltración o las aguas de escorrentía, que pueden transportar plaguicidas y otros contaminantes emergentes empleados en los campos de cultivo. Todos estos vertidos suelen tener un dest…

Restoring ecosystem structure and functions : results from Sphagnum peatlands degraded by forestry drainage

2014

Elemental contamination of an open-pit mining area in the Peruvian Andes

2014

New technologies and higher prices of raw materials have promoted the expansion of mining activity throughout the world; if not properly regulated, this activity can lead to contamination of the local and regional environ- ment. The city of Cerro de Pasco is located close to a large open-pit mine and in recent years, several reports have pro- vided evidence of environmental contamination and related health problems. The aim of this paper is to evaluate the contamination in fluvial water, sediments and biological fluids from this area. The collective results show elevated metal and metalloid concentrations in rivers and sediments, especially in the areas downstream of the mine. For instance,…