Since the late 1990's, the world has seen military planes streaking our skies as if we were corn fields in the process of being dusted.  Many speculations have been made due to the militaries refusal to comment on its actions. Independent scientists have made claims to soil and water samples, containing such toxins as aluminum, barium and strontium. Conspiracy theorists say it is population control, sterile contaminates inhaled to reduce sperm in males, ect... Here is one claim amongst the many that you should consider valid. http://www.naturalnews.com/041201_chemtrails_nanoparticles_degenerative_disease.html#ixzz2Z96Ep0P0