Simultaneous determination of cosmetics ingredients in nail products by fast gas chromatography with tandem mass spectrometry - reviews and online consultation

Simultaneous determination of cosmetics ingredients in nail products by fast gas chromatography with tandem mass spectrometry

Opinion: Simultaneous determination of cosmetics ingredients in nail products by fast gas chromatography with tandem mass spectrometry

The incidence of allergic contact dermatitis (ACD) to cosmetics in the general population is rising with the increasing use of cosmetic products and their proliferation and diversification. The aims of this study were to determine the prevalence of ACD to cosmetics in our setting, analyze changes over time, describe the clinical and epidemiological features of this allergic reaction, and identify the allergens and cosmetics involved. We performed a prospective study at the skin allergy unit in Hospital General Universitario de Valencia in Spain between 2005 and 2013 and compared our findings with data collected retrospectively for the period 1996 to 2004. The 5419 patients who underwent patch testing during these 2 periods were included in the study. The mean prevalence of ACD to cosmetics increased from 9.8% in the first period (1996-2004) to 13.9% in the second period (2005-2013). A significant correlation was found between ACD to cosmetics and female sex but not atopy. Kathon CG (blend of methylchloroisothiazolinone and methylisothiazolinone), fragrances, and paraphenylenediamine were the most common causes of ACD to cosmetics during both study periods, and acrylates and sunscreens were identified as emerging allergens during the second period. - based on

A rapid and sensitive gas chromatography with tandem mass spectrometry (GC–MS/MS) method has been developed and validated to quantitatively determine cosmetic ingredients, such as toluene, N-methylpyrrolidone, 2,4-dihydroxybenzophenone (benzophenone-1, BP-1), and diethylene glycol dimethacrylate, in nail products. In this procedure, test portions were extracted with acetone, followed by vortexing, sonication, centrifugation, and filtration. During the extraction procedure, BP-1 was derivatized making it amenable to GC–MS analysis, using N,O-​bis(trimethylsilyl)​trifluoroacetamide. The four ingredients were quantified by GC–MS/MS in an electron ionization mode. Four corresponding stable isotopically labeled analogues were selected as internal standards, which were added at the beginning of the sample preparation to correct for recoveries and matrix effects. The validated method was used to screen 34 commercial nail products for these four cosmetic ingredients. The most common ingredients detected in the nail products were toluene and BP-1. Toluene was detected in 26 products and ranged from 1.36 to 173,000 μg/g. BP-1 ranged from 18.3 to 2,370 μg/g in 10 products.

Rambutan is commercialized for fresh consumption and industrially processed leaving seed as a major residue. Rambutan seed from the industry is worthy of attention for certain industrial applications and feasibility. Extractive yields and fatty acid compositions of rambutan seed fat obtained under different extraction conditions were studied to assess possible applications on an industrial scale. Maceration in n-hexane for 1 h was shown to be feasible for rambutan seed fat extraction (30.12 ± 0.04%). Re-use of the solvent gave non-significantly different extractive yields (p > 0.05). Oleic and arachidic acids were exhibited as the major fatty acids (31.08 ± 0.75% and 28.65 ± 0.72%) followed by gondoic, palmitic, stearic, isooleic, behenic, linoleic and palmitoleic acids. The physicochemical properties of the fat feasible for an industrial practice were determined, including acid (4.35 ± 0.00 mg KOH/g), iodine (44.17 ± 0.30 g I2/100 g), peroxide (1.00 ± 0.00 g/g), saponification (246.73 ± 0.10 mg KOH/g) and unsaponified (0.10 ± 0.00%) values. This bio-fat with a moisture content of 1.77 ± 0.12% was melted at 46.05 ± 0.05 °C. Stable bar and liquid soaps containing rambutan seed fat were developed. Such application demonstrates the potential of rambutan seed fat as a raw material for the cosmetic and personal care industries. The extraction method was modified to meet requirements for industrial feasibility. This unconventional bio-fat with a specification in terms of fatty acid profiles and physicochemical properties is proposed. Furthermore, the fat is comparable with other vegetable oils and cosmetic ingredients, and is compatible with other cosmetic ingredients.