Chem trails are often visible in the sky these days...they differ from con trails in that they don't disappear but hang around for ages and actually spread wider.
They have been analysed and been found to contain nasties such as Aluminium and Cadmium.
Many believe they are designed to lower our immune systems and leave us open to further illness...this is called a "soft kill" tactic in that death is not instant but gradually over a period of time.
Just google chemtrails and you will find much info about them.

These two photos were taken outside my flat in Slough in September 2009.

If you think the British Government would not do this to YOU just watch this clip...they have been doing it for decades.

VIDEO CLIP about Chemtrails.