Adsorption of Microcystin LR and LW on Suspended Particulate Matter (SPM) at Different pH

Liu, Guangliang; Qian, Yuli; Dai, Shugui; Feng, Nan

doi:10.1007/s11270-008-9635-x

Cited by 37 publications

(25 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, it is known that some cyanotoxins, such as microcystins, can be adsorbed by suspended particles in the water-such as organic detritus- (Morris et al 2000;Liu et al 2008), becoming an additional exposure or immobilization pathway. In the present study, the collected water was filtered, evaluating thereby only the toxicity of water-soluble substances.…”

Section: Discussionmentioning

confidence: 99%

“…The toxicity assessment of purified cyanotoxins might not reflect at all the events occurring in the environment, as it has been demonstrated that their toxicity is susceptible to be modified when they are associated to other molecules (Liu et al 2008). Hence, a better option would be to make assessments with crude extracts, evaluating the toxic effects of the different cellular components after blooms have occurred in natural environments (Sotero-Santos et al 2006).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Microcystis toxigenic strains in urban lakes: a case of study in Mexico City

2010

View full text Add to dashboard Cite

Microcystis is a bloom-forming, common cyanobacterium in urban lakes of Mexico City. To assess the presence of potentially cyanotoxin-producing Microcystis, molecular techniques were applied and acute toxicity bioassays were performed with Daphnia magna neonates exposed to cyanobacterial crude extracts. Toxigenic potential of isolated strains was inferred by amplifying the mcyA-Cd genes and their identity as Microcystis was confirmed through the 16S rDNA and phycocyanin operon amplification. Microcystins synthesized under culture conditions were quantified through ELISA. The acute toxicity bioassays revealed that mortality was independent from the cyanotoxin concentration in some strains; this suggests the presence of other metabolites (different from microcystins) that also exerted an important biological effect. Isolated strains had the mcyA-Cd gene and most of them produced variable amounts of microcystins in the culture conditions used, confirming their toxigenic potential. Results warn about possible toxic effect risks for aquatic biota, neighboring areas, visitors and users of these sites, due to the constant presence of these blooms in the studied water bodies.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Microcystis toxigenic strains in urban lakes: a case of study in Mexico City

2010

View full text Add to dashboard Cite

show abstract

“…In the full-scale trial, there would also have been a significantly higher loading of sediment than in the laboratory trials, where wastewater was collected from the surface of ponds. Adsorption by sediments, and subsequent biodegradation, may have accelerated the reduction of microcystins in the full-scale trial compared to the laboratory trials (Harada and Tsuji, 1998;Liu et al, 2008). Biodegradation, UV radiation and adsorption may all have played a role in the longer term reduction of microcystins from the dissolved phase, and may have accelerated their reduction compared to the smaller scale trials under controlled laboratory conditions.…”

Section: Microcystins Dynamicsmentioning

confidence: 99%

Cyanobacterial and microcystins dynamics following the application of hydrogen peroxide to waste stabilisation ponds

Barrington

Ghadouani

Ivey

2013

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. Cyanobacteria and cyanotoxins are a risk to human and ecological health, and a hindrance to biological wastewater treatment. This study investigated the use of hydrogen peroxide (H 2 O 2 ) for the removal of cyanobacteria and cyanotoxins from within waste stabilization ponds (WSPs). The daily dynamics of cyanobacteria and microcystins (commonly occurring cyanotoxins) were examined following the addition of H 2 O 2 to wastewater within both the laboratory and at the full scale within a maturation WSP, the final pond in a wastewater treatment plant. Hydrogen peroxide treatment at concentrations ≥ 0.1 mg H 2 O 2 µg −1 total phytoplankton chlorophyll a led to the lysis of cyanobacteria, in turn releasing intracellular microcystins to the dissolved state. In the full-scale trial, dissolved microcystins were then degraded to negligible concentrations by H 2 O 2 and environmental processes within five days. A shift in the phytoplankton assemblage towards beneficial Chlorophyta species was also observed within days of H 2 O 2 addition. However, within weeks, the Chlorophyta population was significantly reduced by the re-establishment of toxic cyanobacterial species. This re-establishment was likely due to the inflow of cyanobacteria from ponds earlier in the treatment train, suggesting that whilst H 2 O 2 may be a suitable short-term management technique, it must be coupled with control over inflows if it is to improve WSP performance in the longer term.

show abstract

“…The ionizable groups (two carboxyls and one guanidino) of MCLR can be deprotonated or protonated to make MCLR positive or negative at different pH values, respectively. According to the pKa values of MCLR (pKa 1 , 2.09; pKa 2 , 2.19; pKa 3 , 12.48) (Liu et al 2008), the mass fractions of MCLR species can be calculated as follows:…”

Section: Adsorption Isotherms and Thermodynamicsmentioning

confidence: 99%

Mechanisms and Factors Influencing Adsorption of Microcystin-LR on Biochars

Qiu

Huang

et al. 2014

Water Air Soil Pollut

View full text Add to dashboard Cite

The adsorption of microcystin-LR (MCLR) by biochar has never been well understood. For the first time, the unconventional adsorption of hydrophilic MCLR on wood-based biochars was comprehensively investigated as a function of biochar properties, environmental temperature, solution pH, coexisting dissolved organic matter (DOM), and polar organic competitors. High-temperature-prepared biochar from 700°C (BC-700) and low-temperature-prepared biochar from 300°C (BC-300) were characterized with significantly different surface areas but similar alkaline nature. Despite a very low surface area, BC-300 exhibited very high adsorption capacity, which implies the important contribution of surface groups to biochar. MCLR adsorption on biochars was pH dependent and was strongly reduced by macromolecular DOM. Polycarboxylic aliphatic acids and 2-(2-hydroxyethyl) guanidinium cation, which are similar to specific structural groups in MCLR, exhibited an evident competitive effect. The results indicated that both carboxylic and guanidino groups of MCLR serve significant functions in MCLR adsorption to biochar. The adsorption mechanisms may be primarily related to the columbic attractions and the hydrogen bonding interactions between MCLR and biochar surface. In particular, the irreversible adsorption enhancement of MCLR was observed on BC-700, which suggests that biochar amendment can aid in immobilizing MCLR from water to sediment, thereby prolonging MCLR environmental fate in biocharamended sediment.

show abstract

Adsorption of Microcystin LR and LW on Suspended Particulate Matter (SPM) at Different pH

Cited by 37 publications

References 33 publications

Microcystis toxigenic strains in urban lakes: a case of study in Mexico City

Microcystis toxigenic strains in urban lakes: a case of study in Mexico City

Cyanobacterial and microcystins dynamics following the application of hydrogen peroxide to waste stabilisation ponds

Mechanisms and Factors Influencing Adsorption of Microcystin-LR on Biochars

Contact Info

Product

Resources

About