Abstract

Introduction: Flame retardants (FRs) are synthetic chemicals used as additives in polymer consumer products for safety purposes to reduce their flammability. In addition, some of these chemicals, and mainly the non-chlorinated alkyl phosphates, are used as plasticizers1,2. Brominated FRs have been extensively used, but due increasing evidence of their persistence in the environment and toxicity, their use and production have been banned almost worldwide. This has led to the use of alternative FRs, among which organophosphate esters (OPEs) are major category. However, knowledge about OPEs levels in the environment and health effects is still limited, especially in developing countries.Material and methods: Because these substances are not chemically bonded to polymers, they can be easily released into the atmosphere through volatilization or abrasion of consumer products3. In this study, we analyzed the occurrence of seven target OPEs (tris(chloropropyl) phosphate (TCIPP), tris(2-chloroethyl) phosphate (TCEP), triphenyl phosphate (TPHP), 2-ethylhexyl diphenyl phosphate (EHDPHP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), tris(2-butoxyethyl) phosphate (TBOEP), tricresyl phosphate (TCP)) in atmospheric samples of particulate matter smaller than 2.5 μm in diameter (PM2.5) from Mendoza, Argentina. Samples (n=10) were collected along 24 hours in different points of the studied area using a high-volume active air sampler with Whatman quartz fiber filters (QM-A, 20.3 cm × 25.4 cm) from May to October 2016. Samples were extracted by using a Soxhlet extractor and cleaned using Florisil cartridges before analysis. The quantification of targeted compounds was carried out by gas chromatography in combination with electron capture negative ionization mass spectrometry (GC-ECNI/MS).Results and discussion: The levels of Σ7OPEs were in the range of 304 - 1345 pg/m3, with mean concentrations of 750 pg/m3 ± 314 pg/m3. In all samples, TCIPP was the dominant compound, ranging from 39 to 54% of ΣOPEs, followed by TCEP (16-39%). The concentrations profile found in seven samples was as follows: TCIPP> TCEP> TPHP> EHDPHP> TDCIPP> TBOEP> TCP. Two samples presented small variations in the order of contribution (in one sample EHDPHP>TPHP, and in the other TPHP> TCEP). In the remaining sample, TCP was in the fourth position. The variation in the profile can be explained by the fact that the corresponding measurement site was in the vicinity of the local airport, and this compound is used as an additive in lubricants and hydraulic fluids of aircraft4. Regarding the spatial distribution of OPEs, no clear trends were found.To the best knowledge of the authors, this is the first report on OPEs in atmospheric particulate matter of Argentina, which provides preliminary information about the presence of these substances in the atmosphere of the area and constitutes the basis for future monitoring programs.