Discoloration of the water is often observed at sea, but that is always due.
Owing to impurities contained in the materials from which glasses are made, accidental coloration or discoloration is often produced.
Ferrous oxide is the usual cause of discoloration.
A brown surface deposit is visible causing some discoloration.
If a child's clothing has been wet for a long period of time or the child has been exposed to freezing temperatures, shows skin discoloration, and complains of feeling numb, the child should be seen by a doctor.