Effects of tris(1-chloro-2-propyl)phosphate and tris(2-chloroethyl)phosphate on cell viability and morphological changes in peripheral blood mononuclear cells (in vitro study)

Organophosphorus flame retardants (OPFRs) are a group of chemicals widely used in various everyday use products. Tris(2-chloroethyl)phosphate (TCEP) and tris(1-chloro-2-propyl)phosphate (TCPP) are one of the commonly used chemicals belonging to this group. Due to the need of limitation of the use of polybrominated diphenyl ethers (PBDEs) as retardants, the share of the compounds tested in our experiments in chemicals production systematically increases. There is limited information about the influence of halogenated OPFRs on living cells, especially on the immune system cells. That is why the aim of this study was to assess the impact of TCEP and TCPP on viability and morphological alterations of human peripheral blood mononuclear cells (PBMCs). The cells were incubated with selected flame retardants in the concentrations ranging from 0.001 to 1 mM for 24 h. It was found that TCEP at 1 mM and TCPP at 0.5 mM decreased viability of PBMCs, while only TCPP induced morphological alterations in the incubated cells. The results of our experiments suggest that TCPP is more cytotoxic than TCEP, which can be explained by the presence of methyl groups in the molecule of this compound. Similar to other studies, our data also suggest that OPFRs are suitable replacements for PBDEs.