High Levels of Organophosphate Flame Retardants in the Great Lakes Atmosphere

Levels of 12 organophosphate flame retardants (OPs) were measured in particle phase samples collected at five sites in the North American Great Lakes basin from March 2012 to December 2012 (inclusive). The target compounds were three chlorinated OPs [tris­(2-chloroethyl) phosphate (TCEP), tris­(1-chloro-2-propyl) phosphate (TCPP), and tris­(1,3-dichloro-2-propyl) phosphate (TDCPP)], three alkyl phosphates [tri-n-butyl phosphate (TnBP), tris­(butoxyethyl) phosphate (TBEP), and tris­(2-ethylhexyl) phosphate (TEHP)], and six aryl phosphates [triphenyl phosphate (TPP), tri-o-tolyl phosphate (TOTP), tri-p-tolyl phosphate (TPTP), tris­(3,5-dimethylphenyl) phosphate (TDMPP), tris­(2-isopropylphenyl) phosphate (TIPPP), and tris­(4-butylphenyl) phosphate (TBPP)]. Total OP (ΣOP) atmospheric concentrations ranged from 120 ± 18 to 2100 ± 400 pg/m³ at the five sites, with the higher ΣOP levels detected at Cleveland and Chicago. ΣOP concentrations at these urban sites were dominated by the chlorinated OPs (TCEP, TCPP, and TDCPP), with the sum of these three compounds comprising 51 ± 6 and 65 ± 12% of ΣOP concentrations at these two sites, respectively. Nonhalogenated OP compounds were major contributors to ΣOP concentrations at the remote sites, with the sum of all nine nonhalogenated OP concentrations comprising 70 ± 21 and 85 ± 13% of the ΣOP concentrations at Eagle Harbor and Sleeping Bear Dunes, respectively. On average, these ΣOP concentrations are about 2–3 orders of magnitude higher than the concentrations of brominated flame retardants in similar samples.