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Tris(2-chloroisopropyl) phosphate (TCPP), a widely used organophosphate flame retardant, has been recognized as an important atmospheric pollutant. It is notable that TCPP has potential for long-range atmospheric transport. However, its atmospheric fate is unknown, restricting its environmental risk assessment. Herein we performed quantum chemical calculations to investigate the atmospheric transformation mechanisms and kinetics of TCPP initiated by ·OH in the presence of O/NO/NO, and the effects of ubiquitous water on these reactions. Results show the H-abstraction pathways are the most favorable for the titled reaction. The calculated gaseous rate constant and lifetime at 298 K are 1.7 × 10 cmmolecule s and 1.7 h, respectively. However, when considering atmospheric water, the corresponding lifetime is about 0.5-20.2 days. This study reveals for the first time that water has a negative role in the ·OH-initiated degradation of TCPP by modifying the stabilities of prereactive complexes and transition states via forming hydrogen bonds, which unveils one underlying mechanism for the observed persistence of TCPP in the atmosphere. Water also influences secondary reaction pathways of selected TCPP radicals formed from the primary H-abstraction. These results demonstrate the importance of water in the evaluation of the atmospheric fate of newly synthesized chemicals and emerging pollutants.

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Aqueous ·OH reaction rate constants ( k) for organophosphate esters (OPEs) are essential for assessing their environmental fate and removal potential in advanced oxidation processes (AOPs). Herein experimental and in silico approaches were adopted to obtain k values for a variety of OPEs. The determined k for 18 OPEs varies from 4.0 × 10 M s to 1.6 × 10 M s. Based on the experimental k values, a quantitative structure-activity relationship model that involves molecular structural information on the number of heavy atoms, content index, and the most negative charge of C atoms was developed for predicting k of other OPEs. Furthermore, appropriate density functional theory (DFT) and solvation models were selected, which together with transition state theory were employed to predict k of three representative OPEs. The deviation between the DFT calculated and the experimental k values ( k/ k) is within 2. Half-lives of the OPEs were estimated to be 0.5-22791.3 days in natural waters and 0.044-19.7 s in AOPs, indicating the OPEs are potentially persistent in natural waters and can be quickly eliminated by AOPs. The determined k values and the in silico methods offer a scientific base for assessing OPEs fate in aquatic environments.

Current evidence suggests that GIK with insulin does not reduce mortality in patients with AMI. However, studies of glycaemia are inconclusive and it remains possible that glycaemic control is beneficial.