Q. First priority of phototherapy? 1. Blue light 2. White light
White light... Because exposure of skin to white light converts bilirubin to lumirubin which has a shorter life than bilirubin and are easily excreted.
There is first priority to blue light my dear and ebo also explain in other comment
Light therapy—or phototherapy, classically referred to as heliotherapy—consists of exposure to daylight or to specific wavelengths of light using polychromatic polarised light, lasers, light-emitting diodes, fluorescent lamps, dichroic lamps or very bright, full-spectrum light. The light is administered for a prescribed amount of time and, in some cases, at a specific time of day.
In Jaundice, The absorption of light by normal bilirubin (4Z,15Z-bilirubin) results in the creation of 2 isomeric forms of bilirubin: structural isomers and configurational isomers. The main structural isomer of bilirubin is Z-lumirubin. The main configurational isomer of bilirubin is 4Z,15 E -bilirubin. Configurational isomerization is reversible, and structural isomerization is irreversible. Both the configurational and structural isomers of bilirubin are less lipophilic than normal bilirubin and can be excreted into bile without undergoing glucuronidation in the liver. Some of the configurational isomers of bilirubin, however, revert back to the native form after excretion into bile and can be reabsorbed via enterohepatic circulation in the gut. Structural bilirubin isomers, like Z-lumirubin, can also be excreted in the urine.