Table 1. Preservative systems used for challenge testing

Preservative Suggested Weight (% w/w) Tested Weight (% w/w) Propanediol Weight (% w/w)
Phenoxyethanol (and) Methylparaben (and) Propylparaben (and) Ethylparaben (Microcare PM3, Thor)  0.3–0.7 0.15 0.0, 2.0, 4.0, 6.0
Phenoxyethanol (and) Ethylhexylglycerine (euxyl PE 9010, schulke)  0.5–1.0 0.25 0.0, 2.0, 4.0, 6.0
Phenoxyethanol (and)Methylisothiazolinone (Neolone PE, Dow Chemical) 0.6 0.3 0.0, 2.0, 4.0, 6.0
Phenoxyethanol (and) Caprylyl Glycol (Jeecide CAP-4 Optiphen, Jeen) 0.5–1.5  0.25 0.0, 2.0, 4.0, 6.0
Glyceryl Caprylate (and) Glyceryl Undecylenate (Lexgard Natural, Inolex)  1.0–1.5 0.5 0.0, 2.0, 4.0, 6.0
Anisic Acid (and) Fragrance (parfum) Dermosoft 688 ECO, Dr. Straetmans)  0.2 0.1 0.0, 2.0, 4.0, 6.0
Gluconolactone (and) Sodium Benzoate (Geogard Ultra, Lonza)  1.0 0.5 0.0, 2.0, 4.0, 6.0