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For consumer safety reasons, cosmetics that are exposed to light are evaluated with respect to phototoxicity and/or photoallergy (photosensitization). For perfumes/aftershaves, however, these tests are not performed with the cosmetic product but only with single fragrance compounds, which may influence the outcome. In the presence of a sensitizer, photoinduced oxidation of unsaturated fragrances might result in the formation of unwanted products. Therefore, using real samples, we studied the photodegradation of the common fragrance octahydro tetramethyl naphthalenylethanone (OTNE) under in vitro irradiation, during indoor storage, and after application on skin. OTNE and its photoproducts were determined by liquid chromatography (LC) coupled to diode array detection (DAD). Whereas OTNE itself was photostable, irradiation in the presence of a sensitizer and of aftershave/perfume samples resulted in a strong degradation. Photooxygenation was identified as the major degradation reaction for all three trials. OTNE photooxidation products were characterized by LC-high resolution mass spectrometry (LC-HRMS) and by high-performance thin-layer chromatography (HPTLC) after derivatization with titanium ethoxide and nitrobenzyl pyridine. Both HPTLC and HRMS data indicate that OTNE hydroperoxides are formed during irradiation.

This chapter discusses three cultural institutions–freak show, art photography and fashion modelling–and the respective figures they produced by presenting albinotic bodies. How are bodily deviance and norm negotiated in these cases of structured seeing? Spectacularizing the ‘albino freak’ as a categorical in-between phenomenon, the freak show drew a sharp distinction between the extraordinary figure on stage and its audience while bestowing the latter with normality. On the other hand, Rick Guidotti’s photographic activism invoking ‘positive exposure’ personalizes albinotic subjects and thus partly breaks down the differentiation between deviant other and normal spectator. Finally, in the world of fashion modelling, the albinotic body is again rendered as a spectacle. Extraordinary and beautiful at the same time, this figure, like ‘ordinary’ models, possesses a sought-after distinctiveness while remaining unattainable. Conversely, it bestows its viewers with the ordinariness and normality they hope to transcend.

Tuna fish meat is an expensive and highly perishable sea food. Fresh meat has a bright red colour which soon turns into an unsightly brown during storage. To prolong the aspect of freshness, the red colour is stabilised or even enhanced e.g. with carbon monoxide or nitric oxide, the product of a nitrite / ascorbic acid treatment, which bind as a ligand to myoglobin. These procedures are illegal. Here we present a method for identifying tuna meat samples, which have undergone fraudulent wet salting with nitrite. The method uses headspace-gas chromatography/mass spectrometry (GC/MS) for the determination of nitrous oxide, which is formed as the final product of the two-step reduction nitrite (added agent) to nitric oxide (ligand) to nitrous oxide (target compound). Complex bound nitric oxide is set free with sulfuric acid, which also promotes the reduction to nitrous oxide. The method was validated using 15N labelled nitrite as well as treated and untreated reference fish samples. A survey of 13 samples taken from the Swiss market in 2019 showed that 45 % of all samples were illegally treated with nitrite.

One of the tasks of food law enforcement authorities is to supervise the composition of cosmetics. In the case of mouthwashes, they are likely to contain (labeled or unlabeled) antimicrobial compounds. Conventional analyses, such as high-performance liquid chromatography (HPLC) and gas chromatography (GC) only shed light on a compound’s structure, but not on its biological function. In this study, we demonstrate that the task of detecting antimicrobials in mouthwashes can be streamlined using the luminescent bacterium Vibrio fischeri as a biodetector coupled with high-performance thin-layer chromatography (HPTLC) as a pre-separation method. The employment of subsequent conventional techniques could then be restricted to fractions with proven V. fischeri toxicity. Samples were separated in parallel on silica gel and amino layer HPTLC plates, developed with a solvent system containing tertiary butyl methyl ether and n-hexane and dried on a plate heater. After applying V. fischeri onto the HPTLC plate, zones of interest were extracted from a parallel plate and identified by HPLC–UV or GC-mass spectrometry. The reaction of V. fischeri to more than 40 standard substances which might be present in mouthwashes was determined. Based on this information, six commercially available mouthwashes were analyzed. The workflow proved to be viable for an effect-directed screening for antimicrobial compounds. The analysis of mouthwashes revealed that not only declared preservatives are used (sodium benzoate, cetylpyridinium chloride) but also other compounds, especially constituents of essential oils. Because their main purpose is flavoring of the mouthwash, they are summarized as “aroma” (anethole, carvone, menthol, thymol) which is in compliance with legal restrictions.

Sterol oxidation products (SOPs) are linked to several toxicological effects. Therefore, investigation of potential dietary uptake sources particularly food of animal origin has been a key issue for these compounds. For the simultaneous determination of oxysterols from cholesterol, phytosterols, dihydrolanosterol and lanosterol in complex cosmetic matrices, planar solid phase extraction (pSPE) was applied as clean-up tool. SOPs were first separated from more non-polar and polar matrix constituents by normal phase thin-layer chromatography and then focussed into one target zone. Zone extraction was performed with the TLC-MS interface, followed by gas chromatography-mass spectrometry analysis. pSPE showed to be effective for cleaning up cosmetic samples as sample extracts were free of interferences, and gas chromatographic columns did not show any signs of overloading. Recoveries were between 86 and 113% with relative standard deviations of below 10% (n=6). Results of our market survey in 2016 showed that some cosmetics with ingredients of plant origin contained phytosterol oxidation products (POPs) in the low ppm range and therefore in line with levels reported for food. In lanolin containing products, total SOPs levels (cholesterol oxidation products (COPs), lanosterol oxidation products (LOPs), dihydrolanosterol oxidation products (DOPs)) being in the low percent range exceeded reported levels for food by several orders of magnitudes.

Three cases of fraud with commodities containing illegal stealth compounds are presented, which were uncovered by the State Laboratory Basel-City, Switzerland. All three commodities, grapefruit seed extracts, a phytocosmetical skin cream, and tattoo inks, were produced abroad, had forged declarations of ingredients and, in the case of the extracts and the cream, were marketed with far-reaching health claims. While inspections will identify suspicious products and would be able to eliminate health claims to some extent, only chemical analysis can uncover the illegal agents used and give law enforcement bodies the necessary evidence to immediately clamp down on those brands, where the stealth agent presents a serious health hazard to consumers.

Phthalates are used as plasticizers in many commodities and materials. Therefore, they are found everywhere as contaminants in food and in environmental samples. Due to their potential for developmental and reproductive toxicity, some congeners pose a health risk for consumers and their use is legally restricted with bans and limits. This, however, applies only partly to their usage in cosmetics, toys and packaging materials. Phthalates used as plasticizers in cosmetic packaging could be a previously unknown source of exposure for consumers. In market surveys of the state laboratory of Basel-City, conspicuously high levels of di(2-ethylhexyl) phthalate (DEHP) and di-iso-nonyl phthalate (DINP) were found in shower and bath gels packed in soft PVC shaped as animals or fruits. The concentrations found ranged from 0.02 to 1.3%. It could be shown that concentrations increased significantly during storage. It can therefore be assumed that the phthalates found migrated from the packaging into the gels. The estimated exposure of adults and children to DEHP and DINP of 3.5 and 4.6 μg/kg bw/day, respectively, which may result when using the tested gels does not pose a health risk for the consumer (exposure value below TDI). Regarding the high background contamination levels with phthalates in other sources, exposure from cosmetics should be kept as low as possible. The establishment of limits for phthalates in cosmetics is discussed.

Sunscreen products are meant to protect people from damaging UVA and UVB radiation. However, in some formulations the UV filters they contain can react and form many photodegradation products. Their potential toxicity has not yet been investigated. In this study effect-specific analysis has been used to evaluate the bioactivity of photodegradation products in sunscreens. HPTLC-bioluminescence coupling with the luminescent bacterium Vibrio fischeri was used. Problems in method development were because of the sensitivity of the bacteria and the wettability of HPTLC plates. A separation system using HPTLC LiChrospher plates and automated multiple development (AMD) with tert -butyl methyl ether- n -hexane was chosen. Detection was by UV in addition to Vibrio fischeri . First, biodetection was performed on pure standard solutions of the UV filters. UV filters with molecular weight >400 had no bioactivity; these included all newer UV filters (not in use before 1998). Five commercially available sunscreens with ...

Tattoos fade with time. Part of this fading can be attributed to the photodegradation of pigments. When people get tired of their tattoos, removal by laser irradiation is the method of choice. In vivo laser irradiation of tattoos on mice has shown that the degradation of pigments can result in toxic compounds. Various in vitro studies on photodegradation by sunlight or laser have shown similar degradation products for both irradiations. Even visible light was shown to be able to decompose some pigments to toxic degradation products in vitro. Whereas the investigated phthalocyanins (C.I. 74160, 74260), quinacridones (C.I. 73915) or dioxazines (C.I. 51319) were fairly photostable in vitro, all azo pigments exposed to sunlight or laser were degraded into a variety of products, some of which were toxic or even carcinogenic, such as 2-amino-4-nitrotoluene, 3,3'-dichlorobenzidine and o-toluidine. Up to now, the absence of specific toxicological data is the reason why legal restrictions for tattoo inks are derived from those for cosmetics, toys and textiles. Photodegradation has not been considered. In light of the present analytical findings, even with their possible shortcomings, the evidence weighs heavily enough to consider banning azo pigments containing carcinogenic aromatic amines or allergens in their structure from use in tattoo inks.

Tattoos fade with time. Part of this fading can be attributed to the photodegradation of pigments. When people get tired of their tattoos, removal by laser irradiation is the method of choice. In vivo laser irradiation of tattoos on mice has shown that the degradation of pigments can result in toxic compounds. Various in vitro studies on photodegradation by sunlight or laser have shown similar degradation products for both irradiations. Even visible light was shown to be able to decompose some pigments to toxic degradation products in vitro. Whereas the investigated phthalocyanins (C.I. 74160, 74260), quinacridones (C.I. 73915) or dioxazines (C.I. 51319) were fairly photostable in vitro, all azo pigments exposed to sunlight or laser were degraded into a variety of products, some of which were toxic or even carcinogenic, such as 2-amino-4-nitrotoluene, 3,3'-dichlorobenzidine and o-toluidine. Up to now, the absence of specific toxicological data is the reason why legal restrictions for tattoo inks are derived from those for cosmetics, toys and textiles. Photodegradation has not been considered. In light of the present analytical findings, even with their possible shortcomings, the evidence weighs heavily enough to consider banning azo pigments containing carcinogenic aromatic amines or allergens in their structure from use in tattoo inks.

Nowadays, about 12% of the European and 20% of the US population are tattooed. Rising concerns regarding consumer safety, led to legal restrictions on tattoo inks and permanent make-up (PMU) inks. Restrictions also include bans on certain hazardous colourants. Both ink types use organic pigments for colour-giving, plus inorganic pigments for white and black and colour tones. Pigments are only sparingly soluble in common solvents and occur as suspended particles in the ink matrix. Their detection and identification therefore pose a major challenge for laboratories involved in monitoring the legal compliance of tattoo inks and PMUs. We overcame this challenge by developing a matrix-assisted laser desorption ionisation time-of-flight mass spectrometry method, which included an easy sample clean up. The method proved to be capable of detecting and identifying organic pigments in almost all of the tested ink samples. Method validation and routine deployment during market surveys showed the method to be fit for purpose. Pigment screening of 396 tattoo inks and 55 PMUs taken from the Swiss market between 2009 and 2017 lead to the following conclusions: Pigment variety is much greater in tattoo inks (18) than in PMUs (10); four prohibited pigments (Pigment Green 7, Pigment Red 122, Pigment Violet 19 and 23) were found in both ink types; for PMUs, these four pigments made up 12% of the pigment findings, compared to 32% for tattoo inks. Therefore, legal compliance of PMUs was at a higher level. A comparison of pigments found with those declared on tattoo ink labels clearly showed that banned pigments are rarely declared, but rather masked by listing not present legal pigments and label forging; therefore, highlighting the urgency of widespread market controls.

Samples of urban surface soil, composts, leaves from avenue limetrees and grass from park areas of the city of Basel (Switzerland) were analysed for polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Generally, significant lower levels of PAHs (10 times lower) and heavy metals (3-70 times lower) were found in vegetation samples than in composts or soils. The concentrations of PAHs in soil and compost samples were in the same order of magnitude although 10-100-times higher in comparison to data given for rural soils in other studies, whereas heavy metal contents in urban soils and composts were 2-3 times higher than in rural samples. Using multivariate statistical analysis, it was possible to define similarities or special characteristics of single substances or substance groups in a given matrix reflecting their chemical properties and providing information on their specific emission sources.

High-performance thin-layer chromatography (HPTLC) coupled with bioluminescence detection using Vibrio fischeri bacteria can be used for screening for unknown substances. This is accomplished by dipping the HPTLC plate in an aqueous bacteria solution. Especially polar substances, however, can start to dissolve during this process, which leads to blurring and tailing of the zones on the plate. To overcome this disadvantage, we applied the bacteria solution by rolling. This method has been described for chemical derivatizations, but is very rarely used. The rolling device was made of commercially available household articles. Using octhilinone and methylparaben as test compounds, rolling was compared with dipping. Despite of performing the rolling process manually, the results were reproducible. Depending on the substance and its amount on the HPTLC plate, peaks were narrower, up to a factor of 4 higher and with a higher signal-to-noise ratio than after dipping.