so 1 liter of eye drop per 1ppt of km^3
That would be 1 liter of the active ingredient, not 1 liter of the eye drop. Also I don't believe that 1 ppt of this stuff is harmful when people are putting it directly in their eyes without severe harm.
That would be 1 liter of the active ingredient, not 1 liter of the eye drop. Also I don't believe that 1 ppt of this stuff is harmful when people are putting it directly in their eyes without severe harm.