Bioaccumulation

About: Bioaccumulation is a research topic. Over the lifetime, 7112 publications have been published within this topic receiving 208953 citations. The topic is also known as: bioakumulace.

Fish macroparasites as indicators of heavy metal pollution in river sites in Austria.

Abstract: This paper describes two approaches to evaluate the use of fish macroparasites as bioindicators of heavy metal pollution at selected river stretches in Austria. Firstly changes in the diversity and richness of endoparasites of the cyprinid barbel, Barbrus barbuls (L.), were tested in relation to heavy metal contents in the aquatic system. Secondly, the bioaccumulation potential of cadmium, lead and zinc was assessed in the acanthocephalan, Pomphorhynchus laevis (Miller, 1776), and compared with that in the muscle, liver and intestine of its barbel host. The present results indicated that in order to validate the role of parasite community patterns related to heavy metal pollution, more investigations on food web dynamics, interelationships between parasites and the presence/absence of intermediate hosts will be essential. Heavy metal concentrations differed significantly between the organs of barbel and P. laevis (P=0.001) with levels up to 2860 fold in the parasite. The high level of heavy metal accumulation in P. laevis compared with that in its barbel host, suggests that despite variability in the parasite infrapopulation, host mobility and feeding behaviour, P. laevis is a most sensitive indicator of heavy metals in aquatic ecosystems.

Relationship between reproduction, sediment type, and feeding activity of Lumbriculus variegatus (Müller): Implications for sediment toxicity testing

Abstract: The impact of reproduction and its interaction with sediment type on feeding activity of Lumbriculus variegatus are important because one major pathway in bioaccumulation of hydrophobic sediment-associated contaminants takes place through ingested sediment In this study, the surface egesting behavior and the reproduction of the oligochaete were studied to understand this relationship and to give recommendations for the use of L variegatus in sediment toxicity testing Single individuals were used as replicates allowing proper control of reproduction behavior and egestion rate Reproduction, growth, and egestion rates were clearly different in the two fine-grained unpolluted lake sediments used in the first 28-d experiment The feeding of oligochaetes stopped during the reproduction process in the second 30-d experiment Individuals divided at their middle; the anterior part took 2 d and the posterior part took 6 to 7 d to regenerate new segments and to initiate egestion Culture conditions determined at what size the animals were able to reproduce during the test In our tests 9 mg wet weight was the approximate minimum organism size needed for reproduction behavior Recommendations for sediment toxicity and bioaccumulation testing using L variegatus include using the largest oligochaetes in culture if reproduction is the endpoint and using recently fragmented individuals with complete segments if animals are employed in bioaccumulation tests

Bioaccumulation of Arsenic by Freshwater Algae and the Application to the Removal of Inorganic Arsenic from an Aqueous Phase. Part II. By Chlorella vulgaris Isolated from Arsenic-Polluted Environment

Abstract: Green algae, Chlorella vulgaris Beijerinck var. vulgaris, isolated from an arsenicpolluted environment, was examined for the effects of arsenic levels, arsenic valence, temperature, illumination intensity, phosphate levels, metabolism inhibitors, heat treatment on the growth, and arsenic bioaccumulation. The following conclusions were reached from the experimental results: (a) The growth of the cell increased with an increase of arsenic(V) levels of the medium up to 2,000 ppm, and the cell survived even at 10,000 ppm; (b) The arsenic bioaccumulation increased with an increase of the arsenic level. The maximum accumulation of arsenic was about 50,000 μg As/g dry cell; (c) The growth decreased with an increase of the arsenic(III) level and the cell was cytolyzed at levels higher than 40 ppm; (d) No arsenic(V) was bioaccumulated by a cell which had been pretreated with dinitrophenol (respiratory inhibitor) or with heat. Little effect of NaN3 (photosynthesis inhibitor) on the bioaccumulation was obse...

Biosorption and Bioaccumulation Abilities of Actinomycetes/Streptomycetes Isolated from Metal Contaminated Sites

Abstract: Heavy metal pollution is of great concern. Due to expansion of industrial activities, a large amount of metal is released into the environment, disturbing its fragile balance. Conventional methods of remediation of heavy metal-polluted soil and water are expensive and inefficient. Therefore, new techniques are needed to provide environmentally friendly and highly selective remediation. Streptomycetes, with their unique growth characteristics, ability to form spores and mycelia, and relatively rapid colonization of substrates, act as suitable agents for bioremediation of metals and organic compounds in polluted soil and water. A variety of mechanisms could be involved in reduction of metals in the environment, e.g., sorption to exopolymers, precipitation, biosorption and bioaccumulation. Studies performed on biosorption and bioaccumulation potential of streptomycetes could be used as a basis for further development in this field. Streptomycetes are of interest because of their ability to survive in environments contaminated by metals through the production of a wide range of metal ion chelators, such as siderophores, which provide protection from the negative effects of heavy metals or specific uptake for specialized metabolic processes. Many strains also have the equally important characteristic of resistance to high concentrations of heavy metals.