In vitro study of percutaneous absorption of aluminum from antiperspirants through human skin in the Franz™ diffusion cell.

Aluminum salts such as aluminum chlorohydrate (ACH) are known for use as an active antiperspirant agent that blocks the secretion of sweat. A local case report of hyperaluminemia in a woman using an aluminum-containing antiperspirant for 4 years raises the problem of transdermal absorption of aluminum (Al). Only a very limited number of studies have shown that the skin is an effective barrier to transdermal uptake of Al. In accordance with our analytical procedure, the aim of this study with an in vitro Franz™ diffusion cell was to measure aluminum uptake from three cosmetic formulations of antiperspirant: the base for an "aerosol" (38.5% of ACH), a "roll-on" emulsion (14.5% ACH), and a "stick" (21.2%), by samples of intact and stripped human skin (5 donors). The Al assays were performed by Zeeman Electrothermal Atomic Absorption Spectrophotometry (ZEAAS). Following contacts lasting 6, 12 and 24h, the Al assays showed only insignificant transdermal absorption of Al (≤0.07% of the quantity of Al deposited) and particularly low cutaneous quantities that varied according to the formulations (1.8 µg/cm² for "aerosol base" and "stick" - 0.5 µg/cm² for the "roll-on"). On stripped skin, for which only the "stick" formulation was tested, the measured uptake was significantly higher (11.50 µg/cm² versus 1.81 µg/cm² for normal skin). These results offer reassurance as regards to the use of antiperspirants for topical application of ACH-containing cosmetic formulations on healthy skin over a limited time span (24h). On the other hand, high transdermal Al uptake on stripped skin should compel antiperspirant manufacturers to proceed with the utmost caution.

Fragrance allergy: assessing the safety of washed fabrics.

BACKGROUND: Previously, a quantitative risk assessment suggested there was no risk of induction of fragrance allergy from minor residues of fragrance chemicals on washed fabrics. OBJECTIVE: To investigate whether there was any risk of the elicitation of contact allergy from fragrance chemical residues on fabric in individuals who were already sensitized. METHODS: Thirty-six subjects with a positive patch test to isoeugenol (n = 19) or hydroxyisohexyl 3-cyclohexene carboxaldehyde (n = 17) were recruited. Dose-response and fabric patch tests were performed, respectively, with filter paper and a cotton sample loaded with fragrance in ethanol-diethylphthalate (DEP) and applied in a Finn Chamber or a Hill Top Chamber. RESULTS: Only two subjects reacted to an isoeugenol patch test concentration of 0.01% (>20x the estimated likely skin exposure level), none reacted to lower concentrations. Of 36 subjects, 18 reacted to the fabric patch treated with ethanol-DEP vehicle alone and 20 to the fragrance-chemical-treated fabric patch. These were only minor non-specific skin reactions. They were also quite evenly distributed between the two fragrance chemical allergic groups. CONCLUSIONS: On the basis of the examples studied, fragrance chemical residues present on fabric do not appear to present a risk of the elicitation of immediate or delayed allergic skin reactions on individuals already sensitized.

Fragrance allergy: assessing the risk from washed fabrics.

The prevalence of contact allergy to fragrance ingredients increased during the last part of the 20th century with the consequence that a substantial number of individuals are at risk of experiencing allergic contact dermatitis (ACD) if they have a sufficient degree of skin exposure to the chemical to which they have become sensitized. Such exposure does not necessarily have to arise from the type of source that originally induced the sensitization. A number of sources of exposure are clearly associated with risk of elicitation of ACD, but the role of fragrance deposited on fabrics, for example as a result of laundry processes, also can be questioned. In this article, firstly, the risk of the induction of fragrance-related ACD from exposure to fragrance via fabric is considered. Using a quantitative risk-assessment approach, the risk appears to be extremely low. The possibility that fragrance residues on laundered fabrics might elicit reactions in those already sensitized by a different route is also discussed. Clinically, clothing pattern dermatitis associated with fragrance allergy is almost never observed, although this could be investigated clinically by exposing sensitized individuals to the relevant fragrance allergen.

Inflammatory inert poly(ethylene glycol)--protein wound dressing improves healing responses in partial- and full-thickness wounds.

In this study, a novel soft hydrogel system based on the poly(ethylene glycol)-protein conjugates was evaluated as an occlusive wound dressing material. The hydrogel material, referred by the name of BioAquacare, contains up to 96% of the liquid and is formulated with phosphate-buffered saline and safe preservative to control bacterial load in the open wounds. Performance of the BioAquacare as a wound dressing material was assessed in partial- and full-thickness wounds in pigs. Wound analysis comprised macroscopic determination of the wound size, histological examination of the healing tissues and biochemical characterisation of wound exudates. The wounds treated with BioAquacare healed without any signs of inflammation, skin irritation, oedema or erythema. Cellular composition of the reepithelialised wounds was very similar to that of the normal skin, with a well-developed stratum corneum and epithelial layer. It was observed that BioAquacare plays the role of a liquid compartment, which provides pronounced hydration effect and helps maintain a natural moist environment of the healing tissues. BioAquacare showed relatively low protein-absorbing activity, absorbing predominantly low-molecular-weight molecules, including interleukin (IL)-1beta, IL-6, transforming growth factor-beta1 and products of haemoglobin degradation. It is concluded that application of the moist BioAquacare dressing promotes fast reepithelialisation by creating favourable environment for keratinocytes proliferation and it also reduces scarring. The results show that BioAquacare can be considered as a safe, biocompatible and inflammatory inert wound dressing material.

Treatment costs of three nail lacquers used in onychomycosis.

OBJECTIVE: To assess the daily treatment costs and the average cost-effectiveness of three topical onychomycosis therapies - amorolfine 5% and ciclopirox 8% nail lacquers and tioconazole 28% nail solution - when used as indicated in France, the UK, Germany and Italy. METHODS: The quantity of drug required and nail size measurements were investigated and, knowing the cost per bottle of each study drug, used to calculate the average treatment cost per patient. Using the prevalence of infection data, the weighted average total treatment cost per patient and hence the weighted average daily treatment cost and cost per patient cured, were calculated. RESULTS: Amorolfine was consistently more cost-effective in terms of weighted average daily treatment cost and cost per patient cured than ciclopirox and tioconazole, when all therapies were used as indicated to treat onychomycosis. In France, for example, the weighted average daily treatment cost of amorolfine was found to be euro 0.23 and euro 0.40 when used once and twice a week, respectively; the cost per patient cured for amorolfine was euro 84. By comparison, the weighted average daily treatment cost of ciclopirox was found to be euro 0.81; the cost per patient cured was euro 252. CONCLUSIONS: When used as indicated, amorolfine 5% nail lacquer is more cost-effective than ciclopirox 8% and tioconazole 28% for onychomycosis of toenail, fingernail or both in males and females in France, UK, Germany and Italy.

Allergen penetration through the skin.

The skin is directly in contact with environmental molecules which are present in the air or directly in contact with the epidermis. Despite the assumption that it has a barrier role which could prevent the penetration of molecules, the skin is permeable to all substances from the low molecular weight xenobiotics to the high molecular weight proteins. Only the degree of permeability varies depending on the physiological state of the skin and the chemical properties of molecules. Recent insights into the pathophysiology of allergic skin diseases have shown that allergen penetration is not the major factor in explaining why some patients become allergic while others maintain an immunological tolerance to the penetrating molecules. Indeed, the functional properties of some allergenic molecules able to induce activation of innate immunity appear to be far more important in the development of allergy than their ability to penetrate the skin easily.