If it is true that...

Melatonin can act as a pro-oxidant at physiologically relevant concentrations

and

Almost any kind of stress increases the formation of melatonin

Then it must be true that...

Melatonin reduces behavioral sensitivity but increases the eyes' sensitivity to light, causing them to be injured by light that would otherwise be harmless

If it is true that...

Almost any kind of stress increases the formation of melatonin

Then it must be true that...

Melatonin reduces behavioral sensitivity but increases the eyes' sensitivity to light, causing them to be injured by light that would otherwise be harmless