Perfluoropolyethers in the Prevention of Irritant Contact Dermatitis

Abstract

Background: Perfluoropolyethers (PFPEs) are non-reactive perfluorinated (no hydrogen atoms) liquid polymers that showed promise as ingredients of protective preparations in occupational dermatology. Objective: The aim of this study was to investigate if oil-in-water (o/w) emulsions containing 0.5, 1.0, 2.0 and 4.0% PFPEs (molecular weight 6,250 D) prevent epidermal barrier disruption induced by a repetitive irritation test (RIT). Methods: PFPE-containing o/w emulsions and the emulsion base alone were evaluated against a set of 4 irritants [10% sodium lauryl sulphate (SLS), 0.5% sodium hydroxide (NaOH), 15% lactic acid (LA), and undiluted toluene (TOL)] in the RIT. Ten subjects were tested on the paravertebral skin of the mid-back. Irritation was assessed by visual scoring, transepidermal water loss (TEWL) and colorimetry. Results: Both the emulsion base and all PFPE-containing preparations significantly suppressed irritation by SLS and NaOH. Against LA and TOL, only the 4% PFPE-containing preparation was significant as assessed by TEWL. Conclusion: A 4% PFPE-containing o/w emulsion significantly inhibits irritation due to a wide spectrum of hydrophilic and lipophilic irritants. o/w emulsions with lower concentrations of PFPE are also effective against SLS and NaOH, but this is also true for the cream base alone. Therefore, further studies are necessary to evaluate if a minimum of 4% PFPE in the base provides additional benefit.

Barrier Creams

“…Fomblin HCs form a thin film that does not occlude the pores, and they protect the skin with a dose-related effect. 43,44 Fomblin HC can be incorporated into almost any cosmetic technical form; in the case of emulsions, they may be dispersed by vigorous stirring either in the oily or in the aqueous phase before emulsification. Being insoluble, Fomblin HCs build up a third phase that helps to stabilize the system.…”

Effectiveness of Barrier Creams against Irritant Contact Dermatitis

“…We identified 39 controlled trials (table 1) investigating the effect of BCs against skin irritants in a total of 929 volunteers (172 men, 279 women and 481 unspecified subjects) with healthy skin (n = 28), hand dermatitis (n = 1), skin sensitized to a specific allergen (n = 4) and 1 study on latex glove allergens [6,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52]. From these 39 papers, studies on excised skin [18,24,40,41,43,46] have been discarded, and only trials on subjects with healthy and non-sensitized skin were retained, reducing the list to 27 papers detailed in table 1.…”

“…The contact time of irritants ranges from 5 s to 24 h but the most frequent contact time is 30 min (n = 11) and 24 h (n = 4). Repetitive irritation tests, including repetitive occlusive irritation tests and tandem repetitive irritation tests, were performed in 11 studies [22,23,26,30,31,32,36,38,42,44,50]. The assessment methods often consist of clinical scoring of irritation after cutaneous patch tests (n = 17) and bioengineering methods which are habitually evaporimetry (n = 17), colorimetry (n = 12), corneometry (n = 7), flow velocimetry by Doppler laser (n = 6), spectrometry (n = 3) or other more infrequently used methods.…”

“…In table 3, which reports the presence or absence of efficiency of the named BCs on the 4 most used irritants, we can see that BCs seem to have protective effects against SLS, NaOH and LA, but not against toluene. Four studies [21,31,35,38] compared BCs with vehicles. The results displayed in table 4 show no difference (n = 3) [21,31,38] and a worse effect for scoring and evaporimetry in the last study [35].…”

Are barrier creams actually effective?

“…Another recent study investigated a promising ingredient, PFPEs [12]. These nonreactive liquid polymer compounds were added in different concentrations to an oilin-water emulsion, which was then tested against four irritants (SLS, NaOH, lactic acid, and toluene) in the RIT.…”