A nationwide survey of 31 organophosphate esters in sewage sludge from the United States

Abstract

Organophosphate esters (OPEs) are used as flame retardants and plasticizers in a wide range of consumer products. Nevertheless, studies on the occurrence and inventory of OPEs in sewage sludge are limited. In this study, 20 OP triesters and 11 diesters were measured in 75 archived sewage sludge samples collected from 67 wastewater treatment plants (WWTPs) across the United States (US). The median concentrations of ∑ 20 OP-triesters and ∑ 11 OP-diesters in sludge were 1,290 and 78.4 ng/g dry weight (dw), respectively. Sludge samples originating from the Western and Northeastern US contained higher concentrations of OP triesters than did those from the Midwestern and Southern US. Sludge samples from WWTPs with larger treatment capacity (>38 million liters per day) contained higher concentrations of OP diesters (p <0.05). OP diesters in sludge originated from two sources, triester degradation and direct inputs. Land application of sludge to US soils was estimated to result in annual mass inputs of 12,400-14,900 kg/year of OP triesters and 663-796 kg/year of OP diesters. A hazard assessment was performed for 14 OPEs found in sludge, which suggested a low level of risk from OPs at the current land application practices of sludge.

In Vivo Characterization of the Toxicological Properties of DPhP, One of the Main Degradation Products of Aryl Phosphate Esters

“…2017 ; Li et al. 2019b ; Wang and Kannan 2018 ; Wang et al. 2019 ), either owing to its spontaneous/microorganism production from known APEs ( Fu et al.…”

Residuals, sludge, and biosolids: Advancements in the field

“…Organophosphate (OP) esters (flame retardants, plasticizers) were measured across the U.S. in sludge samples with resulting estimates of mass inputs via land application of 12,400–14,900 kg/year of OP triesters and 663–796 kg/year of OP diesters (Wang, Kannan, Kannan, Halden, & Kannan, 2019). It is also of note hazard assessments conducted for 14 of the OP esters suggested a low level of risk based on current land application practices (Wang et al, 2019).…”

Use of Gasoline, LPG and LPG-HHO Blend in SI Engine: A Comparative Performance for Emission Control and Sustainable Environment

“…This has been extensively reiterated [21,32,33]. To handle the issues related with the gaseous form of hydrogen and the security concerns related with a hydrogen storage tank, it appears to be sensible to produce and utilize hydrogen as hydroxy gas (HHO) through the HHO generation unit [34][35][36]. Several studies concluded that poor burning and lower thermal efficiencies obtained through conventional fuels could be improved when a blend of hydrogen and LPG were utilized as an auxiliary fuel [37,38].…”