TNF and major depressive disorder: Additionally, depression is linked to inflammation.[14] Research shows that chronic stress-induced inflammation affects depression by altering neurotransmitters like serotonin and dopamine through cytokines such as interleukin-1 and tumor necrosis factor-α.[15] Recent studies indicate that blood-derived inflammatory markers, like the platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio, can be biomarkers for depression.[16] However, the role of inflammation in phthalate-related depression is underexplored.