Acidification increases mercury uptake by a freshwater alga, Chlamydomonas reinhardtii

Environmental contextMercury is classified as a priority pollutant owing to the biomagnification of its methylated species along food chains and the consequent effects on top consumers. The pH of natural waters affects many of the biogeochemical processes that control mercury accumulation in aquatic organisms. Here, evidence is presented that pH affects mercury uptake by unicellular algae, primary producers in aquatic food chains, thereby providing a new example of the pervasive influence of pH on the mercury biogeochemical cycle. AbstractWe have examined the influence of pH on HgII uptake (mainly in the form of the lipophilic complex HgCl2) by a green, unicellular alga, Chlamydomonas reinhardtii. Uptake of the dichloro complex increased by a factor of 1.6 to 2 when the pH was lowered from 6.5 to 5.5, an unexpected result given that the intracellular hydrolysis rate of fluorescein diacetate (FDA), used as a probe for the passive diffusion of lipophilic solutes through algal membranes, decreased in the studied alga under similar conditions. Several mechanisms were explored to explain the enhanced uptake at pH 5.5, including pH-induced changes in cell surface binding of Hg or in Hg loss rates from cells, but none of them gave completely satisfactory explanations. The present findings imply that inorganic HgII in aqueous solution behaves, in terms of uptake, neither as a lipophilic complex (the uptake of which would be expected to decrease with acidification because of algal membrane packing), nor as a cationic metal (the transport of which by facilitated transport would be expected to diminish with increasing proton concentration because of metal–proton competition at the transporter binding sites). Mercury uptake by algae seems rather to be stimulated by proton addition.

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Cadmium Adsorption by Chlamydomonas reinhardtii and its Interaction with the Cell Wall Proteins

Environmental Chemistry ◽

10.1071/en04061 ◽

2004 ◽

Vol 1 (3) ◽

pp. 172 ◽

Cited By ~ 24

Author(s):

Heliana Kola ◽

Luis M. Laglera ◽

Nalini Parthasarathy ◽

Kevin J. Wilkinson

Keyword(s):

Cell Wall ◽

Chlamydomonas Reinhardtii ◽

Natural Waters ◽

Anodic Stripping Voltammetry ◽

Aquatic Organisms ◽

Stripping Voltammetry ◽

Regulatory Processes ◽

Realistic Assessment ◽

Cadmium Adsorption ◽

Cd Adsorption

Environmental Context. In natural waters, trace metals levels are largely controlled by microbiology; organisms take up, metabolize, store, and detoxify the metals. However, aquatic organisms may regulate their own uptake via dynamic processes that result in a system that is far from equilibrium. By examining the model title alga with a battery of techniques, a more realistic assessment of metal uptake and metal regulatory processes could be gained. Abstract. Cadmium adsorption by a wild type strain of Chlamydomonas reinhardtii and a cell wall-less mutant was quantified as a function of Cd speciation in a well-defined aqueous medium. For both strains, Cd adsorption to the cell surface was not predicted by a single-site (Langmuirian) model. Indeed, no saturation of the cell wall was observed, even for Cd concentrations in excess of 5 × 10−3 M. A continual production of Cd binding sites appeared to be responsible for the observed increase of Cd adsorption with time. SDS-page separations and measurements of the protein content of algal supernatants demonstrated that organic matter was released by the algae, both in the presence and absence of Cd. Both the nature (e.g. polysaccharides, proteins) and the quantity of exudate production was influenced by the physicochemistry of the external medium. Measurements using the permeation liquid membrane (PLM) and anodic stripping voltammetry (ASV) demonstrated that dissolved cadmium was rapidly complexed by the organic exudates produced by the algae.

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Chlorinated C 1 and C 2 hydrocarbons in the marine environment

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1975.0059 ◽

1975 ◽

Vol 189 (1096) ◽

pp. 305-332 ◽

Cited By ~ 81

Keyword(s):

Carbon Tetrachloride ◽

Acute Toxicity ◽

Microbial Degradation ◽

Chemical Industry ◽

Aquatic Organisms ◽

Trophic Levels ◽

Food Chains ◽

Laboratory Bioassay ◽

Marine Food ◽

Chemical Manufacture

A range of chlorinated hydrocarbons derived from C 1 and C 2 hydrocarbons is manufactured industrially. They are used as intermediates for further chemical manufacture and also outside the chemical industry as solvents or carriers. In the latter category losses in use are eventually dispersed to the environment. The distribution of some of these compounds, including chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene and trichloroethane, in the environment (air, water and marine sediments) has been investigated and the results are presented. The concentrations found have been compared with acute toxicity levels to fish and other aquatic organisms, ascertained by laboratory bioassay. The occurrence of the compounds has been determined in a number of marine organisms, especially those at higher trophic levels, and the accumulation of some of them has been investigated in the laboratory. Chemical and microbial degradation processes have been studied in the laboratory to help determine the course of their removal from the aqueous and aerial environment, and the half lives of some of the compounds have been estimated. It is concluded that these compounds are not persistent in the environment, and that there is no significant bioaccumulation in marine food chains.

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Accumulation and fluxes of mercury in terrestrial and aquatic food chains with special reference to Finland

EUROPEAN JOURNAL OF ENVIRONMENTAL SCIENCES ◽

10.14712/23361964.2015.27 ◽

2013 ◽

Vol 2 (2) ◽

pp. 77-83

Author(s):

Martin Lodenius

Keyword(s):

Special Reference ◽

Food Chains ◽

Aquatic Food

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The Reactions nd resistance of Fishes to Carbon Dioxide and Carbon Monoxide

Illinois Natural History Survey Bulletin ◽

10.21900/j.inhs.v11.365 ◽

1918 ◽

Vol 11 (1-10) ◽

pp. 557-571

Author(s):

Morris Wells

Keyword(s):

Carbon Dioxide ◽

Carbon Monoxide ◽

Fresh Water ◽

Natural Waters ◽

Aquatic Organisms ◽

Toxic Action ◽

Organic Substances ◽

The Many

Carbon monoxide and carbon dioxide are both present in the waste that is diverted into natural waters by many works where illuminating gas is manufactured and, since the waste as a whole is known to be exceedingly poisonous to aquatic organisms, the role played in its toxic action by the two gases in question was investigated at the time that the many other organic substances of which the waste is composed were studied by Shelford. The investigation has shown that both of the gases are poisonous to fresh-water fishes even when present in the water in relatively small proportions, but the monoxide has been found to be by far the more deadly of the two.

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Bioaccumulation and trophodynamics of the antidepressants sertraline and fluoxetine in laboratory-constructed, 3-level aquatic food chains

Environmental Toxicology and Chemistry ◽

10.1002/etc.3637 ◽

2016 ◽

Vol 36 (4) ◽

pp. 1029-1037 ◽

Cited By ~ 13

Author(s):

Marja L. Boström ◽

Gustaf Ugge ◽

Jan Åke Jönsson ◽

Olof Berglund

Keyword(s):

Food Chains ◽

Aquatic Food

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The Fundamentals of Water and Natural Waters

Waste Management ◽

10.4018/978-1-7998-1210-4.ch004 ◽

2020 ◽

pp. 73-101

Author(s):

Benjamin Cuker ◽

George Bugyi

Keyword(s):

Natural Waters ◽

Water Cycle ◽

Intimate Relationship ◽

Aquatic Systems ◽

Structure Of Water ◽

Global Water Cycle ◽

Aquatic Food Chain ◽

Basic Concepts ◽

Aquatic Food ◽

Global Water

This chapter provides information on the fundamental concepts needed to understand water and water pollution, enabling better comprehension of the subsequent material. Examining the molecular structure of water provides context for understanding its most important properties. The reader explores the various types of natural waters and learns how they are tied together in the global water cycle. An examination of the contents of natural waters reveals the presence of dissolved solids, liquids and gases and the intimate relationship between these substances and the community of life that dwells in aquatic systems. The chapter introduces basic concepts of the chemistry of water and discusses the action and distribution of pollutants. Readers also learn about the basic interaction between various pollutants and the aquatic food chain.

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Toxicity Studies on Graphene-Based Nanomaterials in Aquatic Organisms: Current Understanding

Molecules ◽

10.3390/molecules25163618 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3618

Author(s):

Nemi Malhotra ◽

Oliver B. Villaflores ◽

Gilbert Audira ◽

Petrus Siregar ◽

Jiann-Shing Lee ◽

...

Keyword(s):

High Surface ◽

High Surface Area ◽

Aquatic Organisms ◽

Current Understanding ◽

Toxic Effects ◽

Fish Cell ◽

Conductivity Electron ◽

Potential Applications ◽

Aquatic Food ◽

Living Organisms

Graphene and its oxide are nanomaterials considered currently to be very promising because of their great potential applications in various industries. The exceptional physiochemical properties of graphene, particularly thermal conductivity, electron mobility, high surface area, and mechanical strength, promise development of novel or enhanced technologies in industries. The diverse applications of graphene and graphene oxide (GO) include energy storage, sensors, generators, light processing, electronics, and targeted drug delivery. However, the extensive use and exposure to graphene and GO might pose a great threat to living organisms and ultimately to human health. The toxicity data of graphene and GO is still insufficient to point out its side effects to different living organisms. Their accumulation in the aquatic environment might create complex problems in aquatic food chains and aquatic habitats leading to debilitating health effects in humans. The potential toxic effects of graphene and GO are not fully understood. However, they have been reported to cause agglomeration, long-term persistence, and toxic effects penetrating cell membrane and interacting with cellular components. In this review paper, we have primarily focused on the toxic effects of graphene and GO caused on aquatic invertebrates and fish (cell line and organisms). Here, we aim to point out the current understanding and knowledge gaps of graphene and GO toxicity.

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Lake Phytoplankton Assemblage Altered by Irregularly Shaped PLA Body Wash Microplastics but Not by PS Calibration Beads

Water ◽

10.3390/w12092650 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2650

Author(s):

Kiyoko Yokota ◽

Marissa Mehlrose

Keyword(s):

Aquatic Organisms ◽

Environmental Pollutant ◽

Taxonomic Composition ◽

Consumer Products ◽

Source Water ◽

Phytoplankton Assemblage ◽

Phytoplankton Communities ◽

Aquatic Food ◽

And Behavior ◽

Natural Phytoplankton

Microplastics are an emerging environmental pollutant, whose global ubiquity is becoming increasingly evident. Conventional wastewater treatment does not completely remove them, and there are growing concerns about microplastics in source water and post-treatment drinking water. Microplastics have been reported to alter the development, physiology, and behavior of various aquatic organisms; however, limited knowledge exists on their effect on natural phytoplankton communities. Many studies also use uniformly spherical plastic beads, while most scrub particles in consumer products and secondary microplastics in the environment have various shapes and sizes. We tested the effects of two types of microplastics, 50 µm polystyrene (PS) calibration beads and polylactic acid (PLA) plastic body wash scrub particles, and one type of plant-derived body wash scrub particle on a natural phytoplankton assemblage through a 7-day incubation experiment in a temperate, mesotrophic lake. The calibration beads and the plant-derived particles generally did not alter the taxonomic composition of the phytoplankton in the mesocosms, while the PLA body wash microplastics eliminated cryptophytes (p < 0.001) and increased chrysophytes (p = 0.041). Our findings demonstrate differential effects of irregularly shaped PLA body wash microplastics vs. PS calibration beads on lake phytoplankters and empirically support potential bottom-up alteration of the aquatic food web by secondary microplastics.

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