Solvent-free automated thermal desorption-gas chromatography/mass spectrometry for direct screening of hazardous compounds in consumer textiles.

The global production of textiles utilizes numerous large-volume chemicals that may remain to some extent in the finished garments. Arylamines, quinolines, and halogenated nitrobenzene compounds are possible mutagens, carcinogens and/or skin sensitizers. For prevention, control of clothing and other textiles must be improved, especially those imported from countries without regulations of textile chemicals. An automated analytical methodology with on-line extraction, separation, and detection would largely simplify screening surveys of hazardous chemicals in textiles. Automated thermal desorption-gas chromatography/mass spectrometry (ATD-GC/MS) was developed and evaluated as a solvent-free, direct chemical analysis for screening of textiles. It requires a minimum of sample handling with a total run time of 38 min including sample desorption, chromatographic separation, and mass spectrometric detection. For most of the studied compounds, method quantification limit (MQL) was below 5 µg/g for 5 mg of textile sample, which is sufficiently low for screening and control of quinoline and arylamines regulated by EU. Several chemicals were detected and quantified when the ATD-GC/MS method was applied in a limited pilot screening of synthetic fiber garments. A number of arylamines were detected, where some of the halogenated dinitroanilines were found in concentrations up to 300 µg/g. This is ten times higher than the concentration limit for similar arylamines listed by the EU REACH regulation. Other chemicals detected in the investigated textiles were several quinolines, benzothiazole, naphthalene, and 3,5-dinitrobromobenzene. Based on the present results, we suggest ATD-GC/MS as a screening method for the control of harmful chemicals in clothing garments and other textiles.

Diversity and population structure of Nordic potato cultivars and breeding clones.

BACKGROUND: The genetic diversity and population structure of breeding germplasm is central knowledge for crop improvement. To gain insight into the genetic potential of the germplasm used for potato breeding in a Nordic breeding program as well as all available accessions from the Nordic genebank (NordGen), 133 potato genotypes were genotyped using the Infinium Illumina 20 K SNP array. After SNP filtering, 11 610 polymorphic SNPs were included in the analysis. In addition, data from three important breeding traits - percent dry matter and uniformity of tuber shape and eye - were scored to measure the variation potato cultivars and breeding clones. RESULTS: The genetic diversity among the genotypes was estimated using principal coordinate analysis based on the genetic distance between individuals, as well as by using the software STRUCTURE. Both methods suggest that the collected breeding material and the germplasm from the gene-bank are closely related, with a low degree of population structure between the groups. The phenotypic distribution among the genotypes revealed significant differences, especially between farmer's cultivars and released cultivars and breeding clones. The percent heterozygosity was similar between the groups, with a mean average of 58-60%. Overall, the breeding germplasm and the accessions from the Nordic genebank seems to be closely related with similar genetic background. CONCLUSION: The genetic potential of available Nordic potato breeding germplasm is low, and for genetic hybridization purposes, genotypes from outside the Nordic region should be employed.

Suspect and non-target screening of chemicals in clothing textiles by reversed-phase liquid chromatography/hybrid quadrupole-Orbitrap mass spectrometry.

The global manufacturing of clothing is usually composed of multistep processes, which include a large number of chemicals. However, there is generally no information regarding the chemical content remaining in the finished clothes. Clothes in close and prolonged skin contact may thus be a significant source of daily human exposure to hazardous compounds depending on their ability to migrate from the textiles and be absorbed by the skin. In the present study, twenty-four imported garments on the Swedish market were investigated with respect to their content of organic compounds, using a screening workflow. Reversed-phase liquid chromatography coupled to electrospray ionization/high-resolution mass spectrometry was used for both suspect and non-target screening. The most frequently detected compound was benzothiazole followed by quinoline. Nitroanilines with suspected mutagenic and possible skin sensitization properties, and quinoline, a carcinogenic compound, were among the compounds occurring at the highest concentrations. In some garments, the level of quinoline was estimated to be close to or higher than 50,000 ng/g, the limit set by the REACH regulation. Other detected compounds were acridine, benzotriazoles, benzothiazoles, phthalates, nitrophenols, and organophosphates. Several of the identified compounds have logP and molecular weight values enabling skin uptake. This pilot study indicates which chemicals and compound classes should be prioritized for future quantitative surveys and control of the chemical content in clothing as well as research on skin transfer, skin absorption, and systemic exposure. The results also show that the current control and prevention from chemicals in imported garments on the Swedish market is insufficient.

Disperse azo dyes, arylamines and halogenated dinitrobenzene compounds in synthetic garments on the Swedish market.

BACKGROUND: Azobenzene disperse dyes (azo DDs) are well-known as textile allergens, but the knowledge of their occurrence in garments is low. The numerous azo DDs and dye components found in textiles constitute a potential health risk, but only seven azo DDs are included in the European baseline patch test series (EBS). OBJECTIVES: To investigate non-regulated azo DDs and dye components in synthetic garments on the Swedish market. METHODS: High-performance liquid chromatography/mass spectrometry, gas chromatography/mass spectrometry and computerized data mining. RESULTS: Sixty-two azo DDs were detected, with Disperse Red 167:1 occurring in 67%, and 14 other DDs each found in >20% of the garments. Notably, the EBS dyes were less common, three even not detected, while arylamines were frequently detected and exceeded 1 mg/g in several garments. Also, halogenated dinitrobenzenes were identified in 25% of the textiles. CONCLUSION: Azo DDs and dye components, in complex compositions and with large variations, occurred frequently in the synthetic garments. The arylamines were shown to occur at much higher levels compared to the azo DDs, suggesting the former constitute a potentially higher health risk. The role of arylamines and halogenated dinitrobenzenes in textile allergy has to be further investigated.

Tracing colophonium in consumer products.

BACKGROUND: Colophonium (rosin) can cause allergic contact dermatitis, mainly due to autoxidation of abietic acid (AbA). Products containing ≥0.1% colophonium should be labeled with EUH208 - "Contains rosin; colophony. May produce an allergic reaction." How should this be measured? OBJECTIVE: To compare the results from different strategies for estimating colophonium levels in consumer products: (a) from AbA, and (b) the sum of all major resin acids. To investigate the ratio of 7-oxodehydroabietic acid (7-O-DeA)/AbA as indication of autoxidation. METHODS: Resin acids were extracted from consumer products, derivatized, and then separated by gas chromatography/mass spectrometry (GC/MS). RESULTS: Resin acids were detected in 9 of 15 products. No product contained colophonium ≥0.1%. Estimation based on AbA resulted in underestimation of the colophonium levels in four of nine products. For three products, the obtained levels from this strategy were only one of two compared to when estimating from the sum of all resin acids. The ratio 7-O-DeA/AbA varied from 74% to 1.4%. CONCLUSIONS: We propose to measure colophonium based on the sum of all detectable major resin acids, including 7-O-DeA. The ratio of 7-O-DeA/AbA should be used as a marker of autoxidation, indicating an increased risk of sensitization. The presented analytical method is simple to use and suitable for further screening studies.

Allergic contact dermatitis caused by hydroperoxides of limonene and dose-response relationship-A repeated open application test (ROAT) study.

BACKGROUND: Contact allergy to oxidized limonene, with hydroperoxides of limonene (Lim-OOHs) as the main allergens, is common. However, high proportions of weak positive and doubtful patch test reactions have been reported. OBJECTIVES: To determine the clinical relevance, elicitation threshold and dose-response relationship of Lim-OOHs in individuals with a positive or doubtful patch test reaction to standard Lim-OOHs 0.3% pet. METHODS: A multicentre 3-week double-blind vehicle-controlled repeated open application test (ROAT) study with a simulated fine fragrance containing Lim-OOHs at 1260, 420 and 140 ppm, equal to a dose/area per application of Lim-OOHs of 3.0, 0.99 and 0.33 µg/cm2 , was performed. RESULTS: Among 11 subjects allergic to Lim-OOHs, 11 (100%), 7 (64%), and 3 (27%), respectively, reacted to the applied doses. No reactions were seen in 17 healthy controls exposed to the highest dose. This difference in reactivity was statistically significant (P < 0.0001). Among 13 subjects with doubtful patch test reactions to Lim-OOHs, two (15%) had positive ROAT reactions to the highest Lim-OOH dose applied (P = 0.36 as compared with controls). CONCLUSIONS: Contact allergy to Lim-OOHs is of clinical relevance in patients with positive patch test reactions. A doubtful patch test reaction to Lim-OOHs 0.3% pet. can be of clinical relevance.

Effect of a spacer on total systemic and lung bioavailability in healthy volunteers and in vitro performance of the Symbicort® (budesonide/formoterol) pressurized metered dose inhaler.

INTRODUCTION: Many patients with chronic obstructive pulmonary disease or asthma experience difficulties in coordinating inhalation with pressurized metered-dose inhaler (pMDI) actuation. The use of a spacer device can improve drug delivery in these patients. The aim of this study was to establish the relative bioavailability of single doses of Symbicort® (budesonide/formoterol) pMDI 160/4.5 µg/actuation (2 actuations) used with and without a spacer device. In addition, an in vitro study was conducted to characterize performance of the inhaler when used in conjunction with a spacer device. METHODS: A Phase I, randomized, open-label, single-dose, single-center, crossover study in 50 healthy volunteers (NCT02934607) assessed the relative bioavailability of single-dose Symbicort® pMDI 160/4.5 µg/actuation (2 actuations) with and without a spacer (AeroChamber Plus® Flow-Vu®). Inhaled doses were administered without or with activated charcoal (taken orally) to estimate total systemic exposure and exposure through the lung, respectively. The in vitro study characterized the effect of the spacer with respect to delivered dose, fine particle dose, and dose during simulated breathing of budesonide and formoterol. RESULTS: In terms of total systemic exposure, use of the spacer increased the relative bioavailability determined by AUC(0-last) and Cmax by 68% (spacer:no spacer treatment ratio, 167.9%; 90% CI, 144.1 to 195.6) and 99% (ratio, 198.7%; 90% CI, 164.4 to 240.2) for budesonide, and 77% (ratio, 176.6%; 90% CI, 145.1 to 215.0) and 124% (ratio, 223.6%; 90% CI, 189.9 to 263.3) for formoterol, respectively, compared with pMDI alone. Similarly, the lung exposure of budesonide and formoterol increased (AUC(0-last) and Cmax by 146% [ratio, 246.0%; 90% CI, 200.7 to 301.6] and 127% [ratio, 226.5%; 90% CI, 186.4 to 275.4] for budesonide, and 173% [ratio, 272.8%; 90% CI, 202.5 to 367.4] and 136% [ratio, 236.2%; 90% CI, 192.6 to 289.6] for formoterol, respectively) when the pMDI was administered through the spacer. When assessed by AUC(0-last) quartile without spacer, subjects in the lowest exposure quartile (indicating poor inhalation technique) with Symbicort® pMDI 160/4.5 µg/actuation (2 actuations) had markedly increased total systemic and lung exposure when the same dose was administered with the spacer. In contrast, for subjects in the highest exposure quartile with pMDI alone, total systemic and lung exposure of formoterol and budesonide was similar with and without the spacer. In the in vitro study, the fine particle dose (<5 µm) of both budesonide and formoterol from the spacer at delay time (i.e. pause period after actuation) = 0 s (instantaneous) after actuation was similar to the fine particle dose when not using the spacer. The delivered doses of budesonide and formoterol from the spacer were both lower compared with the doses administered without the spacer. There was also a decrease in delivered dose with increasing delay time. CONCLUSIONS: The clinical study demonstrated that in subjects with poor inhalation technique the use of the AeroChamber Plus® Flow-Vu® spacer increased the bioavailability of Symbicort® pMDI to a level observed in subjects with good inhalation technique without a spacer. The findings from the in vitro study support the fine particle dose characteristics of Symbicort® pMDI with the AeroChamber Plus® Flow-Vu® spacer.

Investigation of ultrahigh-performance liquid chromatography/travelling-wave ion mobility/time-of-flight mass spectrometry for fast profiling of fatty acids in the high Arctic sea surface microlayer.

RATIONALE: Fatty acids are enriched in the ocean surface microlayer (SML) and have as a consequence been detected worldwide in sea spray aerosols. In searching for a relationship between the properties of the atmospheric aerosol and its ability to form cloud condensation nuclei and to promote cloud droplet formation over remote marine areas, the role of surface active fatty acids sourced from the SML is of interest to be investigated. Here we present a fast method for profiling of major fatty acids in SML samples collected in the high Arctic (89°N, 1°W) in the summer of 2001. METHODS: Ultrahigh-performance liquid chromatography (UHPLC)/travelling-wave ion mobility spectrometry (TWIMS)/time-of-flight (TOF) mass spectrometry (MS) for profiling was evaluated and compared with UHPLC/TOFMS. Except for evaporation and centrifugation, no sample preparation was necessary prior to the analysis. RESULTS: TOFMS data on accurate mass, isotopic ratios and fragmentation patterns enabled identification of the fatty acids. The TWIMS dimension added to the selectivity by extensive reduction of the noise level and the entire UHPLC/TWIMS/TOFMS method provided a fast profiling of the acids, ranging from C8 to C24 . Hexadecanoic and octadecanoic acids were shown to yield the highest signals among the FAs detected in a high Arctic SML sample, followed by the unsaturated octadecenoic and octadecadienoic acids. The predominance of signal from even-numbered carbon chains indicates a mainly biogenic origin of the detected FAs. CONCLUSIONS: This study presents a fast alternative method for screening and profiling of FAs, which has the advantage of not requiring any complicated sample preparation, thus limiting the loss of analytes. Almost no manual handling, together with the very small sample volumes needed, is certainly beneficial for the determination of trace amounts and should open up the field of applications to also include atmospheric aerosol and fog.

Case Study on Screening Emerging Pollutants in Urine and Nails.

Alternative plasticizers and flame retardants (FRs) have been introduced as replacements for banned or restricted chemicals, but much is still unknown about their metabolism and occurrence in humans. We identified the metabolites formed in vitro for four alternative plasticizers (acetyltributyl citrate (ATBC), bis(2-propylheptyl) phthalate (DPHP), bis(2-ethylhexyl) terephthalate (DEHTP), bis(2-ethylhexyl) adipate (DEHA)), and one FR (2,2-bis (chloromethyl)-propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate (V6)). Further, these compounds and their metabolites were investigated by LC/ESI-Orbitrap-MS in urine and finger nails collected from a Norwegian cohort. Primary and secondary ATBC metabolites had detection frequencies (% DF) in finger nails ranging from 46 to 95%. V6 was identified for the first time in finger nails, suggesting that this matrix may also indicate past exposure to FRs as well as alternative plasticizers. Two isomeric forms of DEHTP primary metabolite were highly detected in urine (97% DF) and identified in finger nails, while no DPHP metabolites were detected in vivo. Primary and secondary DEHA metabolites were identified in both matrices, and the relative proportion of the secondary metabolites was higher in urine than in finger nails; the opposite was observed for the primary metabolites. As many of the metabolites present in in vitro extracts were further identified in vivo in urine and finger nail samples, this suggests that in vitro assays can reliably mimic the in vivo processes. Finger nails may be a useful noninvasive matrix for human biomonitoring of specific organic contaminants, but further validation is needed.

Effector-driven marker development and cloning of resistance genes against Phytophthora infestans in potato breeding clone SW93-1015.

KEY MESSAGE: We show the usefulness of integrating effector screening in a breeding program and in resistance gene cloning, with Phytophthora resistance in the Swedish potato breeding clone SW93-1015 as an example. Phytophthora infestans is one of the most devastating plant pathogens worldwide. We have earlier found that the SW93-1015 potato breeding clone has an efficient resistance against P. infestans under field conditions in Sweden, which has an unusually high local diversity of the pathogen. This potato clone has characteristics that are different from classical R-gene-mediated resistance such as elevated levels of hydrogen peroxide (H2O2) under controlled conditions. Analysis of 76 F1 potato progenies from two individual crosses resulted in nearly 50% resistant clones, from both crosses. This result suggests that the SW93-1015 clone has a simplex genotype for this trait. Screening with over 50 different P. infestans effectors, containing the conserved motif RXLR (for Arg, any amino acid, Leu, Arg), revealed a specific response to Avr2, which suggests that SW93-1015 might contain a functional homolog of the R2 resistance gene. We cloned eight R2 gene homologs from SW93-1015, whereof seven have not been described before and one gene encoded a protein identical to Rpi-ABPT. Expression of this gene in potato cultivar Désirée provided R2-specific resistance, whereas other homologues did not. Using RNAseq analyses we designed a new DNA marker for the R2 resistance in SW93-1015. In summary, we have demonstrated the use of effector screening in practical breeding material and revealed the key resistance mechanism for SW93-1015.

Investigation of diethylthiourea and ethyl isothiocyanate as potent skin allergens in chloroprene rubber.

BACKGROUND: Exposure to chloroprene rubber has resulted in numerous cases of allergic contact dermatitis, attributed to organic thiourea compounds used as vulcanization accelerators. However, thiourea compounds are not considered to be strong haptens. OBJECTIVES: To analyse common commercial chloroprene materials for their contents of diethylthiourea (DETU), dibutylthiourea (DBTU), diphenylthiourea (DPTU), and their degradation products, isothiocyanates; and to investigate the sensitization potencies of possible degradation products of the mentioned thiourea compounds. METHODS: Liquid chromatography/mass spectrometry (MS) was used for quantification of organic thiourea compounds in chloroprene products, such as medical, sports and diving gear; isothiocyanates were measured by solid-phase microextraction/gas chromatography/MS. Sensitization potencies were determined with the murine local lymph node assay (LLNA). RESULTS: DETU was identified at concentrations of 2.7-9.4 µg/cm(2) in all samples, whereas neither DBTU nor DPTU was detected. At 37°C, degradation of DETU in the materials to ethyl isothiocyanate (EITC) was detected. EITC and ethyl isocyanate showed extreme and strong sensitization potencies, respectively, in the LLNA. CONCLUSIONS: DETU can act as a prehapten, being degraded to EITC when subjected to body temperature upon skin contact. EITC could thus be the culprit behind allergic contact dermatitis caused by chloroprene rubber.

LC-MS/MS screening strategy for unknown adducts to N-terminal valine in hemoglobin applied to smokers and nonsmokers.

Electrophilically reactive compounds have the ability to form adducts with nucleophilic sites in DNA and proteins, constituting a risk for toxic effects. Mass spectrometric detection of adducts to N-terminal valine in hemoglobin (Hb) after detachment by modified Edman degradation procedures is one approach for in vivo monitoring of exposure to electrophilic compounds/metabolites. So far, applications have been limited to one or a few selected reactive species, such as acrylamide and its metabolite glycidamide. This article presents a novel screening strategy for unknown Hb adducts to be used as a basis for an adductomic approach. The method is based on a modified Edman procedure, FIRE, specifically developed for LC-MS/MS analysis of N-terminal valine adducts in Hb detached as fluorescein thiohydantoin (FTH) derivatives. The aim is to detect and identify a priori unknown Hb adducts in human blood samples. Screening of valine adducts was performed by stepwise scanning of precursor ions in small mass increments, monitoring four fragments common for the FTH derivative of valine with different N-substitutions in the multiple-reaction mode, covering a mass range of 135 Da (m/z 503-638). Samples from six smokers and six nonsmokers were analyzed. Control experiments were performed to compare these results with known adducts and to check for artifactual formation of adducts. In all samples of smokers and nonsmokers, seven adducts were identified, of which six have previously been studied. Nineteen unknown adducts were observed, and 14 of those exhibited fragmentation patterns similar to earlier studied FTH derivatives of adducts to valine. Identification of the unknown adducts will be the focus of future work. The presented methodology is a promising screening tool using Hb adducts to indicate exposure to potentially toxic electrophilic compounds and metabolites.

Determination of allergenic hydroperoxides in essential oils using gas chromatography with electron ionization mass spectrometry.

Fragrance monoterpenes are widely used commercially due to their pleasant scent. In previous studies, we have shown that air-exposed monoterpenes form hydroperoxides that are strong skin sensitizers. Methods for detection and quantification of the hydroperoxides in essential oils and scented products are thus desirable. Due to thermolability and low UV absorbance, this is a complicated task. We have recently developed a sensitive LC-ESI-MS method, but with limited structural information and separation efficiency for positional isomers and stereoisomers. In the present study, we investigated derivatization with a trimethyl silyl reagent and subsequent GC with electron ionization MS for the determination of monoterpene hydroperoxides. All investigated monoterpene hydroperoxides could be chromatographed as thermostable trimethyl silyl derivatives and yielded the fragment m/z 89 ([OSi(CH3)3](+)) at a higher extent compared to corresponding alcohols. Limonene-2-hydroperoxide and four other hydroperoxide isomers of limonene were separated and detected in sweet orange oil autoxidized for two months. The concentration of limonene-2-hydroperoxide isomers was found to be 19 µg/mg in total. Also isomers of linalyl acetate hydroperoxide and linalool hydroperoxide were detected in autoxidized petitgrain oil (two months). The presented GC-MS method showed concentrations in the same order as previous LC-MS/MS analysis of the same type of oils.

Characterization of skin sensitizers from autoxidized citronellol - impact of the terpene structure on the autoxidation process.

BACKGROUND: Citronellol is a frequently used fragrance compound in consumer products. It is present in fragrance mix II, which is used for screening of contact allergy to fragrances. Because of its chemical structure, citronellol could be susceptible to autoxidation. OBJECTIVES: To compare the behaviour of citronellol with that of the structurally similar compounds linalool and geraniol, in terms of ability to autoxidize, the products formed, and the sensitization potencies of these. METHODS: Citronellol was exposed to air, and autoxidation was followed by gas chromatography-mass spectrometry (GC-MS) analysis after derivatization of thermolabile compounds. The sensitizing potencies of the oxidation mixture and its major oxidation compounds were examined with the local lymph node assay. RESULTS: The concentration of citronellol decreased while the sensitization potency increased in air-exposed samples over time, with hydroperoxides being identified as the major oxidation products and main skin sensitizers. CONCLUSIONS: The present study shows the impact of the absence of the 2,3-double bond in the citronellol structure on the oxidation pathways for formation of oxidation products. The study also shows the usefulness of our new GC-MS method for quantification of the citronellol oxidation products, especially the hydroperoxides. The investigated citronellol hydroperoxides could be important allergens, owing to the high concentrations detected and frequent exposure to citronellol in the population.

Low-Protein Infant Formula Enriched with Alpha-Lactalbumin during Early Infancy May Reduce Insulin Resistance at 12 Months: A Follow-Up of a Randomized Controlled Trial.

High protein intake during infancy results in accelerated early weight gain and potentially later obesity. The aim of this follow-up study at 12 months was to evaluate if modified low-protein formulas fed during early infancy have long-term effects on growth and metabolism. In a double-blinded RCT, the ALFoNS study, 245 healthy-term infants received low-protein formulas with either alpha-lactalbumin-enriched whey (α-lac-EW; 1.75 g protein/100 kcal), casein glycomacropeptide-reduced whey (CGMP-RW; 1.76 g protein/100 kcal), or standard infant formula (SF; 2.2 g protein/100 kcal) between 2 and 6 months of age. Breastfed (BF) infants served as a reference. At 12 months, anthropometrics and dietary intake were assessed, and serum was analyzed for insulin, C-peptide, and insulin-like growth factor 1 (IGF-1). Weight gain between 6 and 12 months and BMI at 12 months were higher in the SF than in the BF infants (p = 0.019; p < 0.001, respectively), but were not significantly different between the low-protein formula groups and the BF group. S-insulin and C-peptide were higher in the SF than in the BF group (p < 0.001; p = 0.003, respectively), but more alike in the low-protein formula groups and the BF group. Serum IGF-1 at 12 months was similar in all study groups. Conclusion: Feeding modified low-protein formula during early infancy seems to reduce insulin resistance, resulting in more similar growth, serum insulin, and C-peptide concentrations to BF infants at 6-months post intervention. Feeding modified low-protein formula during early infancy results in more similar growth, serum insulin, and C-peptide concentrations to BF infants 6-months post intervention, probably due to reduced insulin resistance in the low-protein groups.

Strategy for quantifying trace levels of BMAA in cyanobacteria by LC/MS/MS.

The cyanobacterial neurotoxin ß-N-methylamino-L-alanine (BMAA) is an amino acid that is putatively associated with the pathology of amyotrophic lateral sclerosis/Parkinsonism-dementia complex (ALS-PDC) disease. It raises serious health risk concerns since cyanobacteria are ubiquitous thus making human exposure almost inevitable. The identification and quantification of BMAA in cyanobacteria is challenging because it is present only in trace amounts and occurs alongside structurally similar compounds such as BMAA isomers. This work describes an enhanced liquid chromatography/tandem mass spectrometry platform that can distinguish BMAA from its isomers ß-amino-N-methyl-alanine, N-(2-aminoethyl) glycine (AEG), and 2,4-diaminobutyric acid, thus ensuring confident identification of BMAA. The method's sensitivity was improved fourfold by a post-column addition of acetonitrile. The instrument and method limits of detection were shown to be 4.2 fmol/injection (or 0.5 pg/one column) and 0.1 µg/g dry weight of cyanobacteria, respectively. The quantification method uses synthesized deuterated BMAA as an internal standard and exhibits good linearity, accuracy, and precision. Matrix effects were also investigated, revealing an ion enhancement of around 18 %. A lab-cultured cyanobacterial sample (Leptolyngbya PCC73110) was analyzed and shown to contain about 0.73 µg/g dry weight BMAA. The isomer AEG, whose chromatographic properties closely resemble those of BMAA, was also detected. These results highlight the importance of distinguishing BMAA from its isomers for reliable identification as well as providing a sensitive and accurate quantification method for measuring trace levels of BMAA in cyanobacterial samples.

A sensitive method for determination of allergenic fragrance terpene hydroperoxides using liquid chromatography coupled with tandem mass spectrometry.

Different compositions of monoterpenes are utilized for their pleasant scent in cosmetics and perfumes. However, the most commonly used fragrance terpenes easily oxidize upon contact with air, forming strongly skin-sensitizing hydroperoxides. Due to their thermolability and low UV absorbance, detection methods for hydroperoxides are scarce. For the first time, a simple and sensitive method using LC/ESI-MS/MS was developed to quantitatively determine hydroperoxides from the common fragrance compounds linalool, linalyl acetate, and limonene. The method was applied to autoxidized petitgrain oil and sweet orange oil. A separation was accomplished using a C3 column. The method LOD for the investigated hydroperoxides in the essential oils was below 0.3 µg/mL, corresponding to 0.3 ppm. For prevention purposes and according to EU regulations, concentrations in cosmetics exceeding 100 ppm in "rinse-off" and 10 ppm in "stay-on" products of linalool and limonene must be labeled. However, the products may still contain allergens, such as hydroperoxides, formed by oxidative degradation of their parent terpenes. The sensitivity and selectivity of the presented LC/MS/MS method enables detection of hydroperoxides from the fragrance terpenes linalool, linalyl acetate, and limonene. However, for routine measurements, the method requires further validation.

Patients' Perceptions of Exercise-Based Cardiac Telerehabilitation after a Myocardial Infarction-A Qualitative Study.

To be able to design telerehabilitation programs targeting the needs and preferences of end-users, patients' in-depth perspectives are needed. To date, such studies are lacking and, therefore, the aim of the present study was to describe patients' perceptions of performing exercise-based cardiac telerehabilitation after a myocardial infarction (MI). Individual semi-structured interviews were performed with 15 patients (3 women, median age 69 years) after an MI who had participated in exercise-based cardiac telerehabilitation for three months. The interviews were transcribed verbatim and analyzed with inductive content analysis. An overall theme was defined as "Cardiac telerehabilitation-a new alternative for exercising that is easily accessible and up to date". Four categories, including "The important role of a physical therapist with expert knowledge", "Prerequisites playing an important role in the willingness to participate", "Making exercise accessible and adjustable" and "Inspiring future exercise", and 15 subcategories were identified. Understanding the patient's perspective is an important key to further improving and successfully implementing exercise-based cardiac telerehabilitation, as an alternative or adjunct to traditional, centre-based programs. The findings can serve to improve patient-physiotherapist interactions and to inform important aspects related to exercise, technology and a sense of security from an exercise-based cardiac telerehabilitation program.