A New Structural Classification Scheme for Dissolved Organic Sulfur in Urban Snow from North China

Abstract

The chemical composition of dissolved organic sulfur in snow is important in understanding the sources and scavenging processes of atmospheric organic matter. Snow samples collected simultaneously from four megacities in North China were analyzed using ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The modified oxygen (O*) and redefined aromaticity index (AI*) help interpret the possible structural information and evaluate the aromaticity of sulfur-containing molecules. By extending these parameters, we provide a new structural classification for organic sulfur species in the atmosphere. With the new classification, the oxidized (O/S >3) and less oxidized state (O/S ≤3) sulfur-containing molecules can be easily distinguished. Typical known secondary organosulfates and sulfonates, and

Fractionation and characterization of dissolved organic matter using solid‐phase extraction followed by Fourier transform ion cyclotron resonance mass spectrometry with electrospray, atmospheric pressure photoionization, and laser desorption ionization

“…The results shown in the previous sections demonstrated that MeOH was an effective elution solvent for extracting compounds with sulfonate and sulfate groups. To further investigate the differences within the CHOS class detected by the three ionization modes, the CHO o S compounds can therefore be classified into six subclasses: (i) polycyclic aromatic‐like molecules; (ii) highly aromatic‐like molecules; (iii) highly unsaturated‐like molecules; (iv) unsaturated aliphatic‐like molecules; (v) saturated‐like molecules; (vi) lower oxidation state sulfur‐containing molecules (see the detailed criteria in Table S3 [Supporting Information]) 45 . According to the above classification (Equation [] and []), the i, ii, iii, iv, and v classes are all CHO o S compounds with O > 3, and the vi class is a CHO o S compound with O ≤ 3.…”

“…were subjected to PCA analysis in S3 [Supporting Information]). 45 According to the above classification (Equation [1a] and [1b]), the i, ii, iii, iv, and v classes are all CHO o S compounds with O > 3, and the vi class is a CHO o S compound with O ≤ 3.…”

Molecular Composition of Dissolved Organic Matter in the Changjiang (Yangtze River) – Imprints of Anthropogenic Impact

“…Recent studies indicated that CHOS molecules in urban organic aerosols are highly related to anthropogenic emissions (e.g. cooking and/or biogenic primary emissions) (Su et al, 2022). The population density had a significant positive effect on the contribution of CHOSx formulas, which indicated that human activities act as a potential source of CHOSx and that CHOSx is generally better accumulated and released in high discharge periods.…”

Microbial Transformation of Dissolved Organic Sulfur during the Oxic Process in 47 Full-Scale Municipal Wastewater Treatment Plants

“…Effluents from municipal wastewater treatment plants (WWTPs) are an important source of dissolved organic sulfur (DOS) entering water bodies. Wastewater-derived DOS originates from the sulfidation process of natural organic matter and anthropogenic release of sulfur-containing chemicals (e.g., micropollutants of detergents, surfactants, and drugs) and from microbial metabolism in biological treatment processes in WWTPs (e.g., microbial products of sulfur-containing amino acids and peptides). − DOS in wastewater, which has a potential endocrine disruption effect and exceptionally strong binding affinity with mercury, may reduce water quality in receiving waters. − Additionally, as a major component of dissolved organic matter, DOS presents a special property of forming mercury–DOS complexes, differentiating from other components in dissolved organic matter (e.g., dissolved organic carbon or dissolved organic nitrogen). , The mercury–DOS complexes alter the mobility and bioavailability of mercury and promote the production of neurotoxic methylmercury. , As a consequence of environmental risks posed by DOS, two consecutive publications in the journal Science highlighted that DOS is critical for ecological security in aquatic ecosystems. , The oxic process in municipal WWTPs is the critical contributor for the degradation and removal of various organic matter, which are biologically utilized or decomposed via microbial biochemical reactions in the presence of oxygen. , Microbes in the oxic process are deemed responsible for the changes in dissolved organic matter, including dissolved organic carbon, dissolved organic nitrogen, dissolved organic phosphorus, and DOS. ,, So far, transformation characteristics of carbon, nitrogen, or phosphorus parts in dissolved organic matter have been documented. However, the transformation of DOS and the microbial mechanisms during the oxic process remain poorly understood.…”