Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV; for adequate protection, experts recommend sunglasses that reflect or filter out 99-100% of UVA and UVB light, with wavelengths up to 400 nm.
In 2008, a KSLA news investigation found that a substance that fell to earth from a high altitude chemtrail contained high levels of Barium (6.8 ppm) and Lead (8.2 ppm) as well as trace amounts of other chemicals including arsenic, chromium, cadmium, selenium and silver.
Contrails are ICE. 'CHEMTRAILS' are laid down in a similar way to normal contrails, but do not evaporate; instead they linger in the air, disperse widely and form a greyish, streaky cloud-like cover which can last all day. They are not made of ice crystals, but of solid, very fine, particulate matter.