Barium suppresses immune system
We may have a first understanding of the purpose of chemtrail spraying, i.e., to directly impact the T-cell systems of the humans beneath the chemtrail targets.
Pecanha and Dos Reis (1989) reported in an article entitled "Functional heterogeneity in the process of T lymphocyte activation; barium blocks several modes of T cell activation: published in Clinical Experimental Immunology 1989 May;76(2):311-6, that "All modes of T cell activation, except PHA-induced mitogenesis, were blocked in a reversible and dose-related manner by Ba2+ (barium)." In other words, barium will turn off the body's T-cells. T-cells are an important part of the body's immune system... In short summary, barium can shut down your immune system.