Combined Exposure to Hydrogen Peroxide and LightSelective Effects on Cyanobacteria, Green Algae, and Diatoms

Abstract

The selective toxicity of H2O2 was investigated to develop a potential tool for limiting cyanobacterial blooms and to better understand the occurrence of cyanobacteria and other phytoplankton species in relation to reactive oxygen species in surface waters. The cyanobacterium Microcystis aeruginosa, the green alga Pseudokirchneriella subcapitata, and the diatom Navicula seminulum were tested under pulse exposure to H202 in the dark and at various irradiances. H2O2 was decomposed at rates depending on algal species and was proportional to irradiance. The cyanobacterium was affected by H202 at 10 times lower concentrations than green alga and diatom, and a strong light-dependent toxicity enhanced the difference. The inhibition was measured as photosynthetic yield (Fv/Fm) in pulse amplitude modulated fluorometry, and was confirmed by changes in minimal fluorescence (F0) and photosynthetic oxygen evolution. Single doses of 0.27 mg L(-1) of H202 caused 50% inhibition to M. aeruginosa at high irradiance. Such concentration overlaps with the highest levels of 0.34 mg L(-1) observed in natural waters, suggesting that H202 may act as a limiting factor for cyanobacterial growth.

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO 2 ) and their by-products hydrogen peroxide (H 2 O 2 ) and chlorite (ClO 2 − )

“…This contrasts with the EC 50 (<1 mg PAA/L) reported by, ECETOC, (2001). For hydrogen peroxide Drábková et al, (2007) have reported EC 50 value 21.26 mg/L which is eight times higher than we have obtained. Similarly, van Wijk et al, (1998) has reported EC 50 value of chlorite 0.67 mg/L which is closer to the EC 50 value we obtained.…”

An integrated method for removal of harmful cyanobacterial blooms in eutrophic lakes

“…In this case, the photosynthetic activities of all kinds of algae expressed with Fv/Fm decreased to 0 in few hours. Since some researches suggested that H 2 O 2 could more possibly inactivate cyanobacteria in comparison with other algae (Drábková et al, 2007), H 2 O 2 was specifically used to remove cyanobacteria, but maybe it has some effects on other phytoplankton groups. Also, this method inevitably affects other living organisms in the ecosystem, but the zooplankton might escape to a relative safe area.…”

“…Hydrogen peroxide (H 2 O 2 ), a non-polluting and strong oxidant, was proposed as a potent algaecide in previous research (Drábková et al, 2007), but it cannot effectively remove floating algae by depositing them on the lake bottom. Modified clay was reported to be a common and effective flocculant for removing cyanobacterial blooms (Liu et al, 2010).…”

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

“…Hydrogen peroxide (H 2 O 2 ) has shown promise in reducing cyanobacteria and cyanotoxin concentrations, with increased success when coupled with other chemicals or radiation (Cornish et al, 2000;Drábková et al, 2007;Matthijs et al, 2012). Hydrogen peroxide does not accumulate in the environment, as it is decomposed rapidly to water and oxygen gas via biological, chemical and photochemical mechanisms (Cooper et al, 1994;Drábková et al, 2007).…”

“…Hydrogen peroxide does not accumulate in the environment, as it is decomposed rapidly to water and oxygen gas via biological, chemical and photochemical mechanisms (Cooper et al, 1994;Drábková et al, 2007). The chemical inhibits photosynthetic activity in cyanobacteria by impairing electron transfer and oxygen evolution, which can lead to the inactivation of photosystem II, and eventually cellular death (Samuilov et al, 2004).…”