4-Hydroxybenzoic acid

EU 1223/2009 Annex V — SCCS opinion: Opinion on Parabens

EU 1223/2009 Annex V — SCCS opinion: underarm cosmetics and breast cancer

EU 1223/2009 Annex V — SCCS opinion: Opinion concerning Restrictions on Materials listed in annex VI of Directive 76/768/EEC on Cosmetic Products

EU 1223/2009 Annex V — SCCS opinion: Extended Opinion on the Safety Evaluation of Parabens

Dermal Penetration 2008 Parabens in cosmetic formulations applied to skin penetrate the stratum corneum in inverse relation to the ester chain length.2 Carboxylesterases present in keratinocytes hydrolyze parabens in the skin. The extent of the breakdown to 4-Hydroxybenzoic Acid is different between rodent and human skin. In vitro studies also indicate a difference in the extent of hydrolysis to 4-Hydroxybenzoic Acid, depending on whether viable whole skin or dermatomed human skin is used, with the  Distributed for Comment Only -- Do Not Cite or Quote former having a larger extent of hydrolysis. Chemicals that disrupt the stratum corneum may increase the skin penetration of Methylparaben and possibly Ethylparaben, but do not affect the penetration of parabens with longer ester chains. In Vitro In vitro dermal penetration studies are presented in Table 9. In Franz-type diffusion cells, 2.3% - 3.3% of the applied concentration (0.1%) of Methylparaben penetrated porcine skin (fresh or after stored frozen) in 4 h.33 In 24 h, 2.0% - 5.8% and 2.9% - 7.6% penetrated previously frozen intact and tape- stripped skin, respectively. In full-thickness porcine skin stored frozen, permeability coefficients ranged from 31.3 ± 1.6 to 214.8 ± 40 cm/h x 10-4, decreasing (Methylparaben > Ethylparaben > Propylparaben > Butylparaben) with increasing lipophilicity.34 Increasing the ethanol concentration or the exposure duration increased the retention of the parabens in the dermis, compared to the epidermis. Binary combinations of the parabens reduced their permeation rates, which was attributed by the authors to high retention in the epidermis and dermis. In a different study, the penetration of parabens in 3 commercial facial cream formulations through rabbit ear skin ranged from 20% - 60%, after 8 h in Franz-type diffusion cells, increasing with the water solubility of the paraben (Propylparaben < … [kırpıldı — bölüm toplam 12420 karakter]

EPA ToxValDB skin/eye data — endpoint: Skin Sensitization, classification: Category 6.5B (Category 1). Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: Eye Irritation, classification: Category 6.4A (Category 2A). Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: skin irritation: in vivo, classification: Studies Indicate No Significant Irritation, species: rabbit, study: skin irritation, guideline: OECD Guideline 404 (Acute Dermal Irritation / Corrosion) dated 24th April, 2002 according to EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion) of Council regulation No. 440/2008 according to, year: 2009. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: eye irritation: in vivo, classification: Corrosive or Irritation Persists for &gt; 21 days, species: rabbit, study: eye irritation, guideline: OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion) according to, year: 2010. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: skin sensitisation: in vivo (LLNA), classification: Not likely to be sensitizing, species: mouse, study: skin sensitization, guideline: according to OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay) adopted 24 April 2002, year: 2009. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxCast ER model: NO estrogen receptor activity found (AUC agonist=0, antagonist=0). Tested in 18 in vitro assays. Caveat: this is an in vitro screening model with no dose or exposure context; it does NOT mean an effect occurs in humans at cosmetic use levels.