Abstract:Organophosphorus flame retardants (OPFRs) are one category of emerging contaminates, which pose significant risks to human health and ecosystem. In this study, two typical OPFRs [tris (1-chloro-2-propyl) phosphate (TCPP) and tris (2-chloroethyl) phosphate (TCEP)] were selected as target pollutants. The removal efficiencies, concentration variations along the flow path and the accumulations of these two OPFRs in substrate and plant in integrated vertical-flow constructed wetland (IVCW) with intermittent inflow were investigated. The inflow and outflow mass, accumulation and transformation of TCPP and TCEP in IVCW based on mass balance were analyzed, and the possible transformation mechanisms were discussed. The results show that IVCW could effectively remove TCPP and TCEP, and the removal efficiency of TCPP and TCEP in stable stage after planting plants were 74.1±5.3% and 49.3±5.5% respectively. Constructed wetland system was a converter of OPFRs, and the mass of TCPP and TCEP transformed in IVCW was far greater than that accumulated in substrate and plant(2.37% and 1.67%), which accounting for 59.72% and 44.6% of the total mass flow into the IVCW. Microbial degradation in substrate was an important process of OPFRs removal, and variations of TCPP and TCEP concentrations along the flow path were significantly correlated with the DO consumption rate, and the concentration of degradable organic matter. Plant can enhance the removal performance, but due to the limitation of concentration in plant, it is not practical to significantly improve the removal rate by harvesting or increasing planting density.