Comparative study of the effect of chloro-, dichloro-, bromo-, and dibromoacetic acid on necrotic, apoptotic and morphological changes in human peripheral blood mononuclear cells (in vitro study)

- Effect of haloacetic acids (HHAs) on human blood mononuclear cells (PBMCs) was examined.
- HAAs caused necrotic changes in PBMCs and strongly altered cell size and granulation.
- HAAs, and mainly dichlorinated and dibrominated caused apoptosis of PBMCs.
- Changes in ROS level, mitochondrial potential and caspase 8, 9 and 3 levels were noted.
- Among the compounds studied, dibromoacetic acid caused the strongest changes in PBMCs.

In this study, the effect of monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), monobromoacetic acid (MBAA) and dibromoacetic acid (DBAA) on human peripheral blood mononuclear cells (PBMCs) was assessed. HAAs studied induced at millimolar concentrations necrotic alterations in PBMCs with the strongest effect noted for MBAA and DBAA. Chloro- and bromoacetic acids also provoked changes in PBMCs morphology because they caused a strong decrease in cell size (particularly DCAA and DBAA) and increase in cell granulation (mainly MBAA and DBAA). All HAAs studied, and DCAA and DBAA in particular (at lower concentrations than those, which caused necrosis) induced apoptotic changes, which was confirmed by analysis of alterations in cell membrane permeability and caspase 8, 9 and 3 activation. Moreover, HAAs examined (mainly dihalogenated acids) strongly increased transmembrane mitochondrial potential and enhanced ROS (mainly hydroxyl radical) formation, which was possibly associated with apoptotic changes provoked by those substances. The results showed that DBAA exhibited the strongest effects on PBMCs.