This has no relation to the degradation of nicotine or flavoring.
Darker e-juice will taste the same and smoke the same.
This can be prevented by storing e-juice in a closed dark place or in dark containers.
Nicotine found in e-juice can be absorbed through mucus membranes and even bare skin.
Nicotine when consumed (vaporized), is absorbed through the mucus membranes of the mouth, through and lungs.
Juice can separate if it is not regularly agitated.
Some particles in e-juice are heavier than others and will slowly sink to the bottom of the container.
This process takes a long time and is more commonly noticed in non-steeped juice.
E-juice can evaporate if left in an open container.
Not all e-juice ingredients evaporate at the same rate.
Nicotine is the first element to evaporate resulting in a lower overall nicotine level.
This can be prevented by storing e-juice in a closed dark container.
E-juice can expire.
Despite the incredibly long shelf life, nicotine is the first element to break down. Usually beyond one year.
PG, VG and flavoring degrade far slower than nicotine.
There is no 100% VG juice.
This would be 100% vegetable glycerin. Companies that claim 100% VG are saying their juice contains no additional PG and is considered “max VG” not “100% VG”.