Singlet oxygen in surface waters. 3. Photochemical formation and steady-state concentrations in various types of waters

1986 ◽  
Vol 20 (4) ◽  
pp. 341-348 ◽  
Author(s):  
Werner R. Haag ◽  
Juerg. Hoigne
Keyword(s):  
Steady State ◽  
Singlet Oxygen ◽  
Surface Waters ◽  
Photochemical Formation

Active oxygen species in the liver of rats submitted to chronic hypobaric hypoxia

1993 ◽  
Vol 264 (6) ◽  
pp. C1395-C1400 ◽  
Author(s):  
L. E. Costa ◽  
S. Llesuy ◽  
A. Boveris
Keyword(s):  
Steady State ◽  
Singlet Oxygen ◽  
Active Oxygen Species ◽  
Liver Mitochondria ◽  
Active Oxygen ◽  
Female Rats ◽  
H2o2 Production ◽  
Oxygen Species ◽  
State Concentration

The spontaneous in situ liver chemiluminescence of female rats submitted to 4,400 m (simulated altitude) for 2 mo and of their corresponding controls at sea level was determined as an approach to the measurement of the intracellular steady-state concentrations of singlet oxygen and oxygen free radicals. Spontaneous liver chemiluminescence was decreased by approximately 40% in hypoxic rats, whereas CCl4-induced chemiluminescence was unchanged. Liver mitochondria isolated from hypoxic rats showed a 53% decreased rate of H2O2 production and an increased content of cytochrome b (36%), with normal content of cytochromes c1, c, and a-a3. Superoxide dismutase showed a 26% decrease in activity, whereas catalase and glutathione peroxidase activities were not significantly decreased by this extent of hypoxia. Cytochrome P-450 and glutathione contents were unchanged. There were no significant differences in the hydroperoxide-initiated chemiluminescence (an estimation of tissue chain-breaker antioxidants) of homogenates, mitochondria, and microsomes. Results suggest that in chronic hypoxia there is a lower rate of generation of active oxygen species in liver, leading to a decreased steady-state concentration of singlet oxygen.

Singlet oxygen in surface waters — Part I: Furfuryl alcohol as a trapping agent

Chemosphere ◽  
1984 ◽  
Vol 13 (5-6) ◽  
pp. 631-640 ◽  
Author(s):  
Werner R. Haag ◽  
Ju¨rg Hoigne´ ◽  
Ernst Gassman ◽  
Andre´M. Braun
Keyword(s):  
Singlet Oxygen ◽  
Surface Waters ◽  
Furfuryl Alcohol ◽  
Trapping Agent

Singlet Oxygen Analysis in Irradiated Surface Waters

1986 ◽  
Vol 27 (1-2) ◽  
pp. 137-149 ◽  
Author(s):  
André. M. Braun ◽  
Fritz H. Frimmel ◽  
Jürg Hoigné
Keyword(s):  
Singlet Oxygen ◽  
Surface Waters

Assessing the Source of the Photochemical Formation of Hydroxylating Species from Dissolved Organic Matter Using Model Sensitizers

2021 ◽  
Author(s):  
Kylie Couch ◽  
Frank Leresche ◽  
Claire Farmer ◽  
Garrett McKay ◽  
Fernando Rosario
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Singlet Oxygen ◽  
Natural Waters ◽  
Photochemical Formation ◽  
Photochemical Production

Dissolved organic matter (DOM) is ubiquitous in natural waters and can facilitate the chemi-cal transformation of many contaminants through the photochemical production of reactive inter-mediates, such as singlet oxygen (1O2),...

How quality and quantity of brown carbon influence singlet oxygen production in aqueous organic aerosols

2021 ◽  
Author(s):  
Sophie Bogler ◽  
Nadine Borduas-Dedekind ◽  
Imad el Haddad ◽  
David Bell ◽  
Kaspar Dällenbach
Keyword(s):  
Reactive Oxygen Species ◽  
Steady State ◽  
Quantum Yield ◽  
Singlet Oxygen ◽  
Molecular Oxygen ◽  
Biomass Burning ◽  
Secondary Organic Aerosols ◽  
Organic Aerosols ◽  
Oxygen Species ◽  
Brown Carbon

<p>Singlet oxygen (<sup>1</sup>O<sub>2</sub>) is a reactive oxygen species that has recently gained attention as a competitive oxidant in the atmosphere. This excited state of molecular oxygen is formed by indirect photochemistry in the presence of chromophoric dissolved organic matter (DOM) as sensitizers, molecular oxygen and sunlight. The produced highly reactive intermediate <sup>1</sup>O<sub>2 </sub>is then capable of oxidizing and degrading many organic atmospheric components, thereby affecting their lifetime in the atmosphere. Despite this influence on atmospheric fate, the spatiotemporal distribution of <sup>1</sup>O<sub>2</sub> in particular matter (PM) is currently unknown. We hypothesized that brown carbon in biomass burning organic aerosols emitted during winter in Switzerland would lead to higher <sup>1</sup>O<sub>2</sub> steady-state concentrations in PM compared to summer. Therefore, to advance atmospheric <sup>1</sup>O<sub>2 </sub>research, we investigated the <sup>1</sup>O<sub>2</sub> sensitizing ability of organic aerosols sampled on 24-hour PM10 filters. Specifically, these filters were collected throughout 2013 in Frauenfeld and San Vittore in Switzerland, characterized as urban background and rural traffic measurement stations, respectively. We extracted the water-soluble organic components and quantified <sup>1</sup>O<sub>2 </sub>steady state concentrations as well as <sup>1</sup>O<sub>2</sub> quantum yield. The quantum yield enhances the data intercomparison as this value shows the normalization of <sup>1</sup>O<sub>2 </sub>production as a function of the rate of absorbance of the organic aerosols. In our ongoing efforts of expanding the spatiotemporal scale of our measurements, our results from Frauenfeld so far show a range between 0.38 – 6.05 · 10<sup>-13 </sup>M for <sup>1</sup>O<sub>2 </sub>steady state concentrations and quantum yields up to 2.1± 0.5<sup></sup>%. In preliminary experiments, samples from the rural site San Vittore show similar values, with potentially higher values during periods of significant biomass burning contributions. The values underline <sup>1</sup>O<sub>2</sub>’s<sub></sub>potential importance for atmospheric processing, e.g. comparing to Manfrin et al. (ES&T, 2019)<sup>1</sup> who reported <sup>1</sup>O<sub>2 </sub>steady state concentrations of 3 ± 1 · 10<sup>-14 </sup>M from secondary organic aerosols extracts. More importantly, the filter extracts analyzed thus far show a strong seasonal trend, with increased <sup>1</sup>O<sub>2 </sub>values and higher variability in winter as compared to summer. This result corroborates the hypothesis that there is more chromophoric DOM present in winter, due to a higher fraction of brown carbon emitted e.g. in biomass burning for residential heating. To extend this analysis, we are currently correlating the results for <sup>1</sup>O<sub>2 </sub>with molecular markers based on mass spectrometry data available from previous filter analysis provided by Daellenbach et al., (ACP, 2017)<sup>2</sup>. Finding these correlations will enable the prediction of <sup>1</sup>O<sub>2 </sub>sensitizing abilities of organic material present in the aerosols both qualitatively and quantitatively. In all, our work will help constrain the seasonal relevance of <sup>1</sup>O<sub>2 </sub>photochemistry in the atmosphere.</p><p><strong>References</strong></p><p>1. Manfrin, A. et al. Reactive Oxygen Species Production from Secondary Organic Aerosols: The Importance of Singlet Oxygen. Environmental Science & Technology 53, 8553–8562 (2019).<br>2. Daellenbach, K. R. et al. Long-term chemical analysis and organic aerosol source apportionment at nine sites in central Europe: source identification and uncertainty assessment. Atmospheric Chemistry and Physics 17, 13265–13282 (2017).</p>

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