Serum analysis in women and in vitro skin assay for the assessment of exposure to parabens in antiperspirants.

The present study assessed the exposure to methylparaben (MP) and propylparaben (PP) from antiperspirants in serum of 24 women aged 20-30 years old and an in vitro skin assay. An effective liquid chromatography-tandem mass spectrometry method for the determination of MP and PP levels in serum was developed and validated in the range of 10-100 µg/L; the method was fast, simple, sensitive, linear, precise, and accurate. In addition, a simple and rapid liquid chromatography-ultraviolet detection method for the determination of MP and PP levels in antiperspirants was developed and validated in the range of 2-26 mg/L, which presented satisfactory linearity, precision, and accuracy. Using these two methods, 20 commercial antiperspirants were evaluated, and only three showed MP and PP in the formulation. The antiperspirant containing 0.2% and 0.1% w/w MP and PP, respectively, was given to the volunteers, to estimate the internal dose, and submitted to a pig ear skin permeation assay in Franz diffusion cells, presenting a permeation flux of 32% for MP and 71% for PP. In this assay, both MP and PP permeated the skin; however, there was no correlation between antiperspirant use and paraben serum concentration in the volunteers. Graphical abstract.

A paper platform for colorimetric determination of aluminum hydrochloride in antiperspirant samples.

A simple, fast, low-cost, portable, and eco-friendly method using a spot test on a paper platform, together with diffuse reflectance spectroscopy, was developed and validated for the quantification of aluminum hydrochloride, a potential neurotoxic agent, in antiperspirant samples. The determination of aluminum hydrochloride was performed at a wavelength of 615 nm, by measuring consumption of the purple colorimetric reagent Alizarin S, due to reaction with aluminum. The linear range was from 10.0 to 125.0 mg L-1 and could be described by the equation: AR = 0.4479 - 0.002543 CAl (R = 0.999). The limits of detection (LOD) and quantification (LOQ) were 3.06 and 10.2 mg L-1, respectively. The method was specific, accurate, and repeatable, with relative standard deviation (RSD) <5.0%. The recovery was between 92.2 and 103.4%. The method was successfully used for the determination of aluminum hydrochloride in commercial antiperspirant samples, revealing concentrations below the maximum permitted by current legislation.

Effect of deodorant and antiperspirant use and presence or absence of axillary hair on absorption of testosterone 2% solution applied to men's axillae.

INTRODUCTION: Testosterone 2% solution is applied to axillae and is indicated for testosterone replacement therapy in males deficient in endogenous testosterone. AIM: This open-label crossover study evaluated the effect of deodorant/antiperspirant use and presence or absence of axillary hair on absorption of testosterone solution. METHODS: Healthy males (N = 30; ≥50 years of age with baseline testosterone <400 ng/dL) were randomized to one of four treatment sequences involving six treatments. Each treatment consisted of one 1.5-mL dose of testosterone 2% solution (30 mg of testosterone) applied to each axilla. Axillae were unshaved or shaved, and were untreated or pretreated with deodorant/antiperspirant. MAIN OUTCOME MEASURES: Blood samples were taken over 72 hours after each dose for measuring serum testosterone concentrations. RESULTS: Profiles of mean testosterone concentrations were similar across treatments. For all treatments, area under the concentration-time curve through 24 hours (AUC[0-24] ) and 72 hours (AUC[0-72] ), and maximum total testosterone concentration (Cmax ) were similar except for 15% lower Cmax when treatment was applied after deodorant/antiperspirant to shaved vs. unshaved axillae (least squares mean, 531 ng/dL vs. 626 ng/dL, respectively; P = 0.011). This difference is not considered clinically significant. The 95% confidence intervals for AUC(0-24) , AUC(0-72) , and Cmax fell within the traditional bioequivalence limits of 0.8 to 1.25. Incidence of treatment-emergent adverse events (TEAEs) was low (<15%) in each treatment arm, and most TEAEs were mild. CONCLUSIONS: Absorption of testosterone 2% solution was unaffected by use of deodorant/antiperspirant or by the presence or absence of axillary hair. Testosterone solution was generally well tolerated.

Simulated use and wash-off release of decamethylcyclopentasiloxane used in anti-perspirants.

The cyclic volatile methylsiloxane, decamethylcyclopentasiloxane (D5) is used in a large variety of personal care products. Based on the physical-chemical properties of D5, it is likely that losses due to volatilisation may strongly influence the levels entering the aquatic environment. The aim of this study was to quantify the amount of D5 in waste wash water, after typical application and use in a range of deodorant and anti-perspirant (AP) products. Results implied significant losses after a 24h period (>99.9%), and suggest that the use of D5 in leave-on products, such as deodorants/AP is not likely to contribute a significant down-the-drain emission source. An illustrative example is presented, based on data reporting the use of D5 in a range of personal care products (both wash-off and leave-on), which suggests that the contribution of D5 used in wash-off products to the aquatic environment may be considerably more significant. Limitations associated with our understanding of the actual D5 inclusion levels in the products, the market share of the products containing D5, and the variability of consumer habits, are identified as data gaps that need to be addressed in order to better refine down-the-drain emission estimates.

Skin exposure to deodorants/antiperspirants in aerosol form.

Many cosmetic products are available in spray form. Even though the principal targets of these products are the skin and hair, spraying leads to the partitioning of the product between the target and the surrounding air. In the previous COLIPA study (Hall et al., 2007) the daily use of deodorant/antiperspirant (Deo/AP) in spray form was quantified in terms of the amount of product dispensed from the spray can, without specifically quantifying the product fraction reaching the skin during use. Results of the present study provide this additional information, necessary for a reliable safety assessment of sprayed Deo/AP products. In a novel experimental approach the information obtained from real-life movement analysis (automated motion imaging) of volunteers using their own products was integrated with the aerosol cloud sampling data obtained from the same products, leading to the computation of the product deposited on the skin. The 90th percentile values, expressed as percent deposition relative to the can weight loss after spraying, are 23.5% and 11.4% for ethanol-based and non-ethanol-based products, respectively. Additionally, the study has generated data on the skin area covered by the products, spray duration time, spray angle and spray distance from the skin.

An analytical procedure for the determination of aluminum used in antiperspirants on human skin in Franz™ diffusion cell.

A local case report of hyperaluminemia (aluminum concentration: 3.88 µmol/L) in a woman using an aluminum-containing antiperspirant for 4 years raises the question of possible transdermal uptake of aluminum salt as a future public health problem. Prior to studying the transdermal uptake of three commercialized cosmetic formulas, an analytical assay of aluminum (Al) in chlorohydrate form (ACH) by Zeeman Electrothermal Atomic Absorption Spectrophotometer (ZEAAS) in a clean room was optimized and validated. This analysis was performed with different media on human skin using a Franz(™) diffusion cell. The detection and quantification limits were set at ≤ 3 µg/L. Precision analysis as within-run (n = 12) and between-run (n = 15-68 days) yield CV ≤ 6%. The high analytic sensitivity (2-3 µg/L) and low variability should allow an in vitro study of the transdermal uptake of ACH.

Patterns of aluminum hydroxychloride deposition onto the skin.

BACKGROUND: Aluminum hydroxychloride (AlCl(3) ) is an antiperspirant. AIM: To revisit the AlCl(3) deposition in vivo and in vitro on glass slides and stratum corneum (SC) harvested by cyanoacrylate skin surface strippings (CSSS). METHODS: Transepidermal water loss (TEWL) was assessed following application of 5% AlCl(3) on the forearms. The AlCl(3) -coated skin, glass slides and CSSS were observed using two ultraviolet light-emitting CCD cameras in order to record changes in specular reflectance related to AlCl(3) deposition. In addition, the corneoxenometry bioassay was performed in order to predict AlCl(3) irritation. RESULTS: AlCl(3) deposited on glass slides looked as linear threads and rings of similar sizes. AlCl(3) deposits on skin were almost restricted inside the microrelief lines and as annular deposits at their crossings where acrosyringia are opening. After daily AlCl(3) applications, deposits extended on the CSSS plateaus. At rest in absence of sweating, TEWL was decreased following AlCl(3) applications. During physical exercise, the TEWL increase was limited on the AlCl(3) areas. CSSS appeared unreactive to AlCl(3) at the corneoxenometry bioassay. CONCLUSION: The similar aspect of AlCl(3) deposits on human SC and on glass slides suggested a physical property of AlCl(3) . Repetitive applications of AlCl(3) increased both the deposit area and the barrier function.

Determination of triclosan in antiperspirant gels by first-order derivative spectrophotometry.

A first-order derivative UV spectrophotometric method was developed to determine triclosan, a broad-spectrum antimicrobial agent, in health care products containing fragrances which could interfere the determination as impurities. Different extraction methods were compared. Triclosan was extracted with chloroform and diluted with ethanol followed by the derivative spectrophotometric measurement. The interference of fragrances was completely eliminated. The calibration graph was found to be linear in the range of 7.5-45 microg x mL(-1). The method is simple, rapid, sensitive and proper to determine triclosan in fragrance-containing health care products.

Validated flow-injection method for rapid aluminium determination in anti-perspirants.

A flow-injection (FI) method for the rapid determination of aluminium in anti-perspirants has been developed. The method is based on the spectrophotometric detection at 535nm of the complex formed between Al ions and the chromogenic reagent eriochrome cyanine R. Both the batch and FI methods were validated by checking the parameters included in the ISO-3543-1 regulation. Variables involved in the FI method were optimized by using appropriate statistical tools. The method does not exhibit interference from other substances present in anti-perspirants and it shows a high precision with a R.S.D. value (n=6) of 0.9%. Moreover, the accuracy of the method was evaluated by comparison with a back complexometric titration method, which is currently used for routine analysis in pharmaceutical laboratories. The Student's t-test showed that the results obtained by both methods were not significantly different for a significance level of 95%. A response time of 12s and a sample analysis time, by performing triplicate injections, of 60s were achieved. The analytical figures of merit make the method highly appropriate to substitute the time-consuming complexometric method for this kind of analysis.