Organophosphate triesters (tri-OPEs) are synthetic phosphate derivatives that are primarily used as flame retardants and plasticizers. Tri-OPEs have become significant aquatic contaminants owing to their large production volumes and wide range of applications. Organophosphate diesters (di-OPEs) are closely related to tri-OPEs. Aside from emissions resulting from the production and usage of di-OPEs themselves, tri-OPEs can become transformed into di-OPEs, which also provides a significant source of this environmental contaminant. The physicochemical properties of a di-OPE depend significantly on its structure, which provides challenges for their detection and analysis, including low extraction efficiencies, chromatographic separation difficulties, and a lack of highly sensitive quantitative methods for their analysis. An increasing number of studies have found that di-OPEs are present in industrial/domestic wastewater, surface water, and drinking water, with some concentrations in surface water and tap water close to or even higher than those of the corresponding tri-OPEs. Additionally, certain di-OPEs are somewhat more toxic than the corresponding tri-OPEs; hence, awareness that di-OPEs are present in aquatic environments has raised widespread concern. This review first systematically outlines the physicochemical properties of common di-OPEs and their potential sources based on previous research into di-OPEs in water matrices. In addition, the use of solid phase extraction (SPE) technology to extract, enrich, and purify di-OPEs from water matrices is summarized, while the advantages and limitations of SPE methodologies are critically evaluated. Furthermore, the use and distinctive features of reverse-phase chromatography, ion-pair reverse-phase chromatography, and hydrophilic interaction liquid chromatography (HILIC) for the chromatographic separation of di-OPEs are comprehensively summarized and compared. At the same time, advances in the quantitative analysis of di-OPEs using liquid chromatography-tandem triple quadrupole mass spectrometry (LC-MS/MS) and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) are reviewed. Finally, in terms of efficient collection of water samples and high-throughput pretreatment of di-OPEs in water matrices, the prospect of developing novel sampling and on-site enrichment technologies for new pollutants in water matrices based on the principle of dispersed solid phase extraction is proposed. Additionally, the prospect of using liquid chromatography tandem high-resolution mass spectrometry for high-throughput screening and high-sensitivity detection of di-OPEs and unknown transformation products of tri-OPEs has been proposed.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |