Potassium sorbate, 100 µg/mL in Methanol

Propyl paraben

Propyl paraben, 100 µg/mL in Methanol

Propylene glycol (PG), 100 µg/mL in Methanol

Protocatechuic acid

Protocatechuic acid, 100 µg/mL in Acetonitrile

Pyrocatechol

p-Phenylenediamine (PPD), 100 µg/mL in Methanol

Polyethylene glycol (PEG), appr, Molecular weight 1500

Polyethylene glycol (PEG), appr, Molecular weight 200