Molecular Weight

166.17 g/mol

Molecular Formula

C₉H₁₀O₃

XLogP3

2.5

Hydrogen Bond Donor Count

Hydrogen Bond Acceptor Count

Rotatable Bond Count

Exact Mass

166.062994177 g/mol

Monoisotopic Mass

166.062994177 g/mol

Topological Polar Surface Area

46.5 Å²

Heavy Atom Count

Formal Charge

Complexity

148

Isotope Atom Count

Defined Atom Stereocenter Count

Undefined Atom Stereocenter Count

Defined Bond Stereocenter Count

Undefined Bond Stereocenter Count

Covalently Bonded Unit Count

By the oral route, parabens are rapidly absorbed, metabolized, and excreted. The metabolic reactions and conversions in mammals vary with the chain length of the ester, the animal species, route of administration, and quantity tested. The metabolism of parabens in humans appears to be most closely related to that of dogs. The rate of metabolite excretion appears to decrease with increasing molecular weight of the ester. /4-Hydroxybenzoates (Parabens)/

Bingham, E.; Cohrssen, B.; Powell, C.H.; Patty's Toxicology Volumes 1-9 5th ed. John Wiley & Sons. New York, N.Y. (2001)., p. V6 639

... Deposition of parabens in dogs. Urine recoveries ranged from 50-95% except for butyl ester for which recoveries were 40%. /It/... was concluded that esters are well absorbed and that hydrolysis of ester linkage and metabolic conjugation constitute chief route of elimination. Similar metabolic scheme ... in man. /Parabens/

Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972., p. 126

The permeation of methylparaben, ethylparaben, propylparaben, and butylparaben through untreated and lipid-depleted excised guinea pig dorsal skin, and the effects of 3 penetration enhancers, N-dodecyl-2-pyrrolidone (lauryl pyrrolidone), ethyl alcohol (ethanol), and a mixture of menthol (l-menthol) and ethyl alcohol, on the permeation of the parabens were studied; the relationship between the permeability and octyl alcohol (n-octanol)/water partition coefficients of the parabens, and the effect of the penetration enhancers on the fluidity of the lipid bilayer of liposomes containing stratum corneum lipids were also examined. Permeability coefficients of the parabens correlated with their octyl alcohol/water partition coefficients in untreated guinea pig skin. In lipid-depleted guinea pig skin, permeability coefficients of the parabens increased and did not correlate with their octyl alcohol/water partition coefficients. The effect of the penetration enhancers on the permeation of the parabens was variable. The penetration enhancers increased the fluidity of liposome lipid bilayers.

After ethyl paraben is intravenously infused into the dog, unhydrolyzed ethyl paraben is found only in the brain. In liver, kidney, and muscle, it is immediately hydrolyzed to p-hydroxybenzoic acid. Six hours after oral administration of 1.0 g/kg to dogs, the peak plasma concentration of free and total ethyl paraben (427 and 648 ug/cu cm, respectively) is reached. After 48 hr, all ethyl paraben is completely eliminated.

Bingham, E.; Cohrssen, B.; Powell, C.H.; Patty's Toxicology Volumes 1-9 5th ed. John Wiley & Sons. New York, N.Y. (2001)., p. V6 668