Photoreactivity of humic substances: relationship between fluorescence and singlet oxygen production

  title={Photoreactivity of humic substances: relationship between fluorescence and singlet oxygen production},
  author={Christian Coelho and Ghislain Guyot and Alexandra ter Halle and Luciano Cavani and Claudio Ciavatta and Claire Richard},
  journal={Environmental Chemistry Letters},
Humic substances are natural compounds abundantly present in the environment. They play a significant role in the natural attenuation of pollution in surface water due to their capacity to generate reactive species upon solar light excitation. Finding physico chemical parameters related to this property would be of a great help in the prediction studies of the organic pollutants fate. In this work, we investigated relationships between the ability of the humic substances to produce singlet… 

Fluorescence analysis allows to predict the oxidative capacity of humic quinones in dissolved organic matter: implication for pollutant degradation

Dissolved organic matter (DOM) controls the degradation and sequestration of aquatic pollutants and, in turn, water quality. In particular, pollutant degradation is performed by oxidant species that

Photosensitised humic-like substances (HULIS) formation processes of atmospheric significance: a review

Formation of higher molecular weight compounds, modification of the wettability properties of organic films and photoproduction of substances with humic-like fluorescence properties have been observed as a consequence of the photosensitised reactions.

Photosensitised HULIS (humic-like substances) formation processes of atmospheric significance: A review

Photosensitised reactions can produce compounds that closely resemble the humic-like substances (HULIS) occurring in atmospheric aerosols. The relevant processes have been observed in the laboratory,

The Investigation of Photocatalysts and Iron Based Materials in the Oxidation and the Adsorption of Toxic Organic and Chromium Materials

The presences of heavy metals, organic contaminants and natural toxins in natural water bodies pose a serious threat to the environment and the health of living organisms. Therefore, there is a

Synergistic photogeneration of reactive oxygen species by dissolved organic matter and C60 in aqueous phase.

This study demonstrates the importance of considering DOM when investigating ROS production by C60, and enhanced O2(•–) generation for HA/C60 mixture was because (3)C60* mediated electron transfer from photoionized HA to O2.

Radical chemistry of dissolved black carbon under sunlight irradiation: quantum yield prediction and effects on sulfadiazine photodegradation

The findings indicate that the simple models of the RI quantum yield as a function of spectral parameters can be used to evaluate the degradation of pollutants with known DBC spectral parameters.

Fluorescence quenching as an indicator of the conformational change of humic acids.

Humic acids as a water soluble fraction of humus play important role in the plant growth. Even though structure of humic acids is not clear, their spectroscopic properties can reveal us useful



Photogeneration of singlet oxygen by humic substances: comparison of humic substances of aquatic and terrestrial origin.

A general trend towards higher PhiDelta in terrestrial HS was observed and the comparison of reverse osmosis isolates from surface waters collected during fall 1999 and spring 2000 from five Scandinavian sites yielded, in all cases, higher Phi delta for the spring samples.

Quantifying interactions between singlet oxygen and aquatic fulvic acids.

Results from this study demonstrated that 1O2 reacts with microbially and terrestrially derived DOM at rate constants comparable to phenols, naphthols, or aromatic amines, on a per carbon basis.

Microheterogeneity of Singlet Oxygen Distributions in Irradiated Humic Acid Solutions

This work assessed the microheterogeneous distribution of 1O2 in irradiated solutions containing chromophoric dissolved organic matter (CDOM) by using molecular probes of varying hydrophobicity using recently developed hydrophobic trap-and-trigger chemiluminescent probe molecules.

Reactive photoinduced species in estuarine waters. Characterization of hydroxyl radical, singlet oxygen and dissolved organic matter triplet state in natural oxidation processes.

  • Fadi al HousariD. VioneS. ChironS. Barbati
  • Chemistry, Environmental Science
    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology
  • 2010
A kinetic model is developed describing the solar photo-transformation of xenobiotic organic compounds induced by the three different photooxidants HO*, (1)O(2) and (3)CDOM*.


Fifty samples of humic acids and fulvic acids isolated from various soils and soil-related materials (including paleosols, peat, leonardite, composted and earth-worm-composted organic materials,

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

Separation of natural aquatic organic compounds by gel permeation chromatography resulted in fractions showing little correlation between /sup 1/O/sub 2/ production efficiency and molecular weight, indicating that large macromolecular structures are not a prerequisite for the sensitization of /sup 2/ formation.

Relationship between photosensitizing and emission properties of peat humic acid fractions obtained by tangential ultrafiltration.

The first order rate constant of FFA photo-oxygenation increased with the intensity of fluorescence at 380, 430, and 500 nm, and a plot of k* versus IF* indicates that the distribution of fluorescent centers among fractions paralleled that of photosensitizing centers.

Inhibition of humic substances mediated photooxygenation of furfuryl alcohol by 2,4,6-trimethylphenol. Evidence for reactivity of the phenol with humic triplet excited states.

By postulating that 2,4,6-trimethylphenol competes with oxygen for reaction with humic triplet excited states and with furfuryl alcohol for Reaction with singlet oxygen, kinetic laws describing the consumption profiles of furf Furyl alcohol and 2, 4, 6- Trimethyl phenol are obtained.