Effect of oxidant demand on the release and degradation of microcystin-LR from Microcystis aeruginosa during oxidation

Copyright © 2017 Elsevier Ltd. All rights reserved..

In this research, the release and degradation of intracellular microcystin-LR (MC-LR) due to oxidation of Microcystis aeruginosa (M. aeruginosa) was examined kinetically. Brief exposure to free chlorine with no measureable oxidant exposure was demonstrated to be sufficient to induce rapid release of intracellular MC-LR from M. aeruginosa. Thus, in a water treatment plant, there is currently no level of prechlorination that can be assumed to be safe, since very low preoxidation prior to filtration and no measureable free chlorine residual may still observe the release and buildup of extracellular MC-LR. Higher chlorine dosages resulting in a measureable exposure or CT (concentration times contact time) cause more rapid release and oxidation of the intracellular toxins. Further, the rate of release of MC-LR with intermediate oxidant dosages were shown to be initially rapid, but then slowed to a lower release rate due to an as yet undetermined mechanism. While free chlorine was reactive with the extracellular MC-LR, the monochloramine resulting from the consumption of the free chlorine by ammonia was not. Consideration of the ammonia concentration and the chlorine dosage relative to the chlorination breakpoint dosages is important for utilities assessing the impact of prechlorination of water containing cyanobacteria. MC-LR, once released, was rapidly oxidized by permanganate resulting in only negligible buildup of extracellular toxins.

Medienart:

E-Artikel

Erscheinungsjahr:

2017

Erschienen:

2017

Enthalten in:

Zur Gesamtaufnahme - volume:181

Enthalten in:

Chemosphere - 181(2017) vom: 15. Aug., Seite 562-568

Sprache:

Englisch

Beteiligte Personen:

Zhang, Haiting [VerfasserIn]
Dan, Yongbo [VerfasserIn]
Adams, Craig D [VerfasserIn]
Shi, Honglan [VerfasserIn]
Ma, Yinfa [VerfasserIn]
Eichholz, Todd [VerfasserIn]

Links:

Volltext

Themen:

14333-13-2
4R7X1O2820
Cell lysis
Chlorination
Chlorine
Cyanoginosin LR
EQ8332842Y
Journal Article
Manganese Compounds
Marine Toxins
Microcystin-LR
Microcystins
Microcystis aeruginosa
Oxidants
Oxides
Permanganate
Permanganic acid
Toxin release rate

Anmerkungen:

Date Completed 08.08.2017

Date Revised 09.12.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.chemosphere.2017.04.120

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM271494441