The impact of inorganic tin on the planktonic cyanobacterium Synechocystis aquatilis: the effect of pH and humic acid

Acclimation response and ability of growth and photosynthesis of terrestrial cyanobacterium Cylindrospermum sp. strain FS 64 under combined environmental factors

This investigation tested the hypothesis that the native cyanobacteria can acclimatize and grow under the combination of environmental factors and/or how does their process change with the age of culture? Here, we tried to combine multiple factors to simulated what happens in natural ecosystems. We analyzed the physiological response of terrestrial cyanobacterium, Cylindrospermum sp. FS 64 under combination effect of different salinity (17, 80, and 160 mM) and alkaline pHs (9 and 11) at extremely limited carbon dioxide concentration (no aeration) up to 96 h. Our evidence showed that growth, biomass, photosystem II, and phycobilisome activity significantly increased under 80 mM salinity and pH 11. In addition, this combined condition led to a significant increase in maximum light-saturated photosynthesis activity and photosynthetic efficiency. While phycobilisomes and photosystem activity decreased by increasing salinity (160 mM) which caused decreased growth rates after 96 h. The single-cell study (CLMS microscopy) which illustrated the physiological state of the individual and active-cell confirmed the efficiency and effectiveness of both photosystems and phycobilisome under the combined effect of 80 mM salinity and pH 11.

Effects of organic matter components and incubation on the cement-based stabilization/solidification characteristics of lead-contaminated soil

Stabilization/solidification (S/S) has been studied since 1950s and widely used for the treatment of potentially toxic elements (PTEs). The coexistence of organic matter (OM) and PTEs can cause a very complicated mechanism for cement-based S/S applications and bring challenges from both scientific and engineering perspectives. To fill in the knowledge gap, this paper investigates for the first time the effects on S/S characteristics of OM components and incubation, which are the two main factors that result in the inconsistency in the leaching characteristics from the available studies. OM samples with different components (humic acid (HA) and fulvic acid (FA)) and contents were mixed into lead-contaminated soil and incubated for different durations of up to 90 days. The experimental results show that the strength of stabilized soils increases with increasing incubation duration and the lead leaching concentration of stabilized soils is decreased by 60.7%-83.6% from zero to 90 days. The lead leaching concentration of the HA group, which is 144.0% higher with no incubation than the non-OM group, becomes 58.3% lower with 90 days of incubation. The leaching concentration of the FA group remains much higher than those of the other groups. Finally, a competing mechanism of HA-weakening cement hydration reactions and stabilizing lead with a critical incubation duration of 14 days-is proposed, together with a cooperating mechanism of FA-weakening cement hydration reactions and releasing lead.

μ-Thin-layer chromatography coupled with laser ablation-inductively coupled plasma-mass spectrometry using tin(II)-imprinted polymer nanoparticles as a stationary phase for speciation of tin

A unique and novel μ-thin-layer chromatography method based on Sn(II) ion-imprinted polymer (Sn-IIP) for speciation of tin ion species in water and plasma samples is introduced for the first time. For this purpose, N-allylthiourea (NATU) and ethylene glycol dimethacrylate (EGDMA) were copolymerized in the presence of Sn(II). The obtained polymer particles were identified using multiple techniques like BET, FT-IR, XRD, and FESEM. The effects of different variables such as pH of the solution, mobile phase composition, and IIP per CaSO₄ mass ratio on the separation efficiency were also evaluated. After completion of the separation process on the plate, its surface was scanned by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Under the established optimal condition, the detection limit, relative standard deviation (RSD) of responses, and linear dynamic range (LDR) of the method were obtained as 0.3 μg L^-1, 3.5%, and 0.8-900 μg L^-1 for Sn(II) and 0.4 μg L^-1, 4%, and 1-740 μg L^-1 for Sn(IV) assay, respectively. The developed method was finally applied to the speciation of tin in various water and plasma samples. Graphical abstract Schematic representation of μ-thin-layer chromatography method based on tin(II) ion-imprinted polymer (Sn-IIP) for speciation of tin ion species in water and plasma samples and scanned separated casts by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).

Tin compounds in food - their distribution and determination

The aim of this work was optimization of the methods of trace- and ultratrace analysis, such as ICP-OES, ETA-AAS for charting the resources of individual forms of tin in foodstuffs. Increase of the sensitivity of the method of ICP-OES was achieved using the techniques of generation of hydrides, which was also optimized. Based on the information available on the occurrence of the different forms of tin, it appears that many of these organometallic compounds are contained in marine animals; attention has mainly focused on organisms such as marine fish, crustaceans, molluscs and algae. Tin compounds of predominantly inorganic origin can be found in foods and beverages which are packed in cans with a protective tin coating, too. The above mentioned methods have been applied to the analysis of selected beverages with low content of tin such as Coca Cola, Sprite, Fanta, Gambrinus 10°, PowerKing, and milk in the cans. Furthermore samples of animal origin as Sardines in oil, and Hunter's salami were examined, too. Prior to the determination of tin, samples need to be appropriately modified or analysed. Decomposition of the samples was done in the microwave system. Low pressure ion exchange chromatography with on-line detection of ICP-OES was used for separation of inorganic tin compounds. Separation of organically bound tin compounds was performed by HPLC on a column of ACE C-18, 3 µm, 15 cm × 1.0 mm with off-line detection by ETA-AAS. All of the above forms of tin compounds can be separated with this column. Due to the improvement in the detection of organically bounded tin, HPLC with identical ACE C-18 column coupled online for example with ICP-MS or spectrofluorimetry could be recommended.

Manganese-mefenamic acid complexes exhibit high lipoxygenase inhibitory activity

The coordination of non-steroidal anti-inflammatory drugs (NSAIDs) to metal ions could improve the pharmaceutical efficacy of NSAIDs due to the unique characteristics of metal complexes.

The toxicity of selected trace metals to Lecane inermis rotifers isolated from activated sludge

The aim of the study was to assess the toxicity of a range of trace metals to the rotifer Lecane inermis, a species tested as a potential biological tool to control activated sludge bulking caused by overgrowth of filamentous bacteria in wastewater treatment plants. LC50 values (concentration lethal to 50 % of individuals, mg dm(-3)) were ranked in the following order: Cu < Al < Fe < Zn < Sn < Mn. L. inermis apparently is more sensitive to metals than other aquatic species widely used as model organisms in ecotoxicological testing, making it potentially useful for quick ecotoxicological tests.

Dissolved inorganic tin sources and its coupling with eco-environments in Bohai Bay

Dissolved inorganic tin (DISn) and its spatial variation were examined in Bohai Bay seawaters to understand the DISn behavior and pollution in this area. DISn concentration gradually increased with the distance from the coast and showed a slight decrease with the increasing depth from surface water, suggesting the scavenged behavior of tin with an atmospheric input to surface water. Besides, the higher DISn values also were found near the Haihe Estuary inferring that the riverine input was a source of DISn. Based on the data in this study, a preliminary estimate of the tin budget via riverine input and atmospheric deposition has been established. According to our estimate, about 2 × 10(6) and 8.47 × 10(5) g/year of tin reach Bohai Bay via rivers and atmosphere. Environmental factors such as suspended particulate material, salinity, total organic matter, pH, nutrients, and phytoplankton had the important influences on DISn distribution. Among them, the negative correlation between DISn and phytoplankton at most stations might indicate the biological uptake of tin.

Effect of (C6H5)3PbCl and (C6H5)3SnCl on delayed luminescence intensity, evolving oxygen and electron transport rate in photosystem II of Chlorella vulgaris

The effect of the organometallic compounds containing lead, (C6H5)3PbCl , and tin, (C6H5)3SnCl, on Chlorella green algae photosystem II was studied. Suspension of the algae treated with (C6H5)3SnCl at concentrations of 1.0 and 4.0 micromol dm(-3) for 22 h revealed a decrease in most physiological parameters studied, particularly in decasecond component of delayed chlorophyll luminescence, photosynthetic electron transport rate and diluted oxygen concentration, which implies an inhibition of photosynthetic electron transport as well as oxygen evolving system. On the other hand, (C6H5)3PbCl caused stronger inhibition than (C6H5)3SnCl, particularly in the higher concentration.

Cyanobacteria Metal Interactions: Requirements, Toxicity, and Ecological Implications

The environmental health-related relevance of cyanobacteria is primarily related to their ability to produce a wide range of toxins, which are known to be hazardous to many organisms, including human beings. The occurrence of cyanobacterial blooms has been related to eutrophic surface water. In the bloom-forming process the levels of phosphorus and nitrogen have been well documented but information regarding concentrations of other chemicals (inorganic, organo-metallic, and organic) is still incipient. Several contaminants, like trace metals, elicit a variety of acute and chronic toxicity effects, but cyanobacteria also have the capability to accumulate, detoxify, or metabolize such substances, to some extent. The role of cyanobacterial exudates has been proved a means of both nutrient acquisition and detoxification. In addition, cyanobacteria are effective biological metal sorbents, representing an important sink for metals in aquatic environment. Understanding the fundamental physicochemical mechanisms of trace metal bio-uptake by cyanobacteria in natural systems is a step towards identifying under what conditions cyanobacterial growth is favored and to ascertain the mechanisms by which blooms (and toxin production) are triggered. In this review the cyanobacterial interactions with metals will be discussed, focusing on freshwater systems.

Case study: bioavailability of tin and tin compounds

This article reviews the literature related to the bioavailability of tin, inorganic tin compounds, and organotin compounds. On the one hand, the toxicity of metallic tin and inorganic tin compounds is low. In aqueous systems, the potential bioavailability of tin seems to depend on the concentration of the truly dissolved ion species. Some studies suggest that tin is an essential trace element for humans. However, organotin compounds have been proven to be of toxicological relevance. Triorganotin compounds are particularly toxic explaining their wide use as biocides (e.g., in antifouling paints or pesticides). Persistence of organotin compounds is governed by moderate to fast aerobic biotic degradation processes, slow anaerobic biotic degradation, slow abiotic degradation by photolysis, and fast, but reversible, adsorption/desorption processes. Organotin compounds are ubiquitously distributed in aquatic organisms. Bioconcentration in organisms and ecotoxicity are dependent on the bioavailable fraction. The bioavailability is highest at neutral and slightly alkaline pH and is reduced in the presence of dissolved organic carbon. The biomagnification of organotin compounds via the food chain is of minor importance compared with the bioconcentration from the water phase.

Correlations between toxic Pb effects and production of Pb-induced thiol peptides in the microalga Stichococcus bacillaris

Comparing Pb toxicity to the green alga Stichococcus bacillaris and production of Pb-induced thiol peptides in 24-h exposed cells made it possible to show the level of these peptides to reflect Pb availability to algal cells. LC-ESI/MS analysis of these peptides confirmed that they are phytochelatins PC2-PC4 and their des-Gly derivatives. Studies were carried out at environmentally relevant pH values (5-8.5) and various concentrations of hardness cations (Ca, Mg) and orthophosphate: (0-0.1 mM), chloride (0-100 mM), citrate (0-1 mM), and humic acids (0-10 mg/l). It has been stated, on the basis of the level of Pb-induced thiol peptides, that Pb availability to algae changed significantly within the range of the pH values studied, and was limited in the presence of calcium and of some complexing ligands like orthophosphate, chloride and citrate; it did not decrease in the presence of magnesium or humic acid.