Does Usage Of Hydrogen Peroxide Restrain From Getting Positive Results For Drug Test?

The new uk law for drug driving is that police will now have a drugalyser (drug breathalyser), i am a frequent cannabis user and i do drive alot but i limit myself to not driving until 4 hours have been up since i have smoked... If i use mouthwas or hydrogen peroxide right before being pulled over and tested will i fail or pass the test?