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Background: The European Code Against Cancer (ECAC) aims to increase the awareness of modifiable cancer risk factors among the general public. A goal set by the European Commission was that 80% of European citizens should be aware of this code by 2025. This study aims to examine the awareness and attitudes towards the ECAC among the general public in Sweden.

Methods: A randomly selected sample of 1520 Swedes (18–84 years old) were recruited from a survey panel and invited to respond to an online study-specific questionnaire. The questionnaire included general questions regarding cancer prevention, as well as awareness and attitudes specific to the ECAC. Data were analysed univariately and with adjusted logistic regression, using post-stratification weights based on gender, age, education, and expressed political party orientation.

Results: In total, 3.7% of the respondents had heard about the ECAC before taking this survey. Respondents with a college/university education were more likely to have heard about the ECAC (odds ratio [OR] 2.23; 95% confidence interval [CI] 1.23–4.06). Males (OR 0.56; 95% CI 0.32–0.99), and those living alone (OR 0.47; 95% CI 0.23–0.95) were less likely to have heard about the ECAC. In total, 60.6% of the respondents agreed with the ECAC recommendations, while 27.4% reported that their motivation to improve their lifestyle increased after reading the ECAC.

Conclusions: Awareness of the ECAC among the general public in Sweden is very low. Still, a majority seem to agree with its recommendations. The results also indicate that the ECAC motivates some, but far from all, to improve their lifestyle habits to reduce their cancer risk. Consequently, further research is warranted on how the ECAC best could and should be used in order to improve cancer prevention awareness and motivation.

Volatile organic compounds were personally sampled by people classified as cases (people having certain SBS symptoms) and controls, i.e. people not fulfilling the criteria's for cases. The aim of the study was to find out which adsorbent that gave the best separation between SBS cases and controls based on their chemical exposure of VOCs. The statistical method used was partial least squares discriminant analysis (PLS-DA). The adsorbents compared were Carbopack B, Chromosorb 106 and Tenax TA. The study included 30 office workers wearing diffusive samplers during one working week. The samplers were analysed with thermal desorption-GC-MS, and each chromatographic peak was included in the data evaluation. Tenax TA gave the best separation between cases and controls with a Q(2) = 0.434 and R(2)Y = 0.873 for three components. Analyses of samples taken with Carbopack B and Chromosorb 106 showed no ability to discriminate between the two classes.

High-performance liquid chromatography with mass spectrometric detection was used for the structure elucidation of eighteen primary and secondary amines and ammonia derivatised with naphthylisothiocyanate (NIT). A fragmentation scheme was established using reference compounds and the scheme was applied to real air samples from a tyre repair shop and from the air above a bacterial culture. The sampling was performed using a solid sorbent, XAD-2, impregnated with NIT, and the derivatives were extracted with acetonitrile and analysed with LC-MS/MS. A three-step process was developed for screening and identifying of volatile amines. The first step, selected reaction monitoring; SRM was applied in order to screen the samples for NIT derivatives. In the second step, a precursor ion scan gave the [M+H]+ ion, and in the third step a product ion scan gave the fragments needed for identification. The detection limits varied between 0.12 and 0.25 ng μL−1 when screening for unknown derivatised amines. It was possible to separate and identify all the amines with the structural information obtained and the method proved to be general, sensitive and well suited for sampling and analysis of complex environmental samples.

Growth of different microorganisms is often related to dampness in buildings. Both fungi and bacteria produce complicated mixtures of volatile organic compounds that include hydrocarbons, alcohols, ketones, sulfur- and nitrogen-containing compounds etc. Microbially produced substances are one possible explanation of odour problems and negative health effects in buildings affected by microbial growth. A mixture of five fungi, Aspergillus versicolor, Fusarium culmorum, Penicillium chrysogenum, Ulocladium botrytis and Wallemia sebi were grown on three different humid building materials (pinewood, particle board and gypsum board) and on one synthetic medium. Six different sampling methods were used, to be able to collect both non-reactive volatile organic compounds and reactive compounds such as volatile amines, aldehydes and carboxylic acids. Analysis was performed using gas chromatography, high-performance liquid chromatography and ion chromatography, mass spectrometry was used for identification of compounds. The main microbially produced metabolites found on pinewood were ketones (e.g. 2-heptanone) and alcohols (e.g. 2-methyl-1-propanol). Some of these compounds were also found on particle board, gypsum board and the synthetic medium, but there were more differences than similarities between the materials. For example, dimethoxymethane and 1,3,5-trioxepane and some nitrogen containing compounds were found only on particle board. The metabolite production on gypsum board was very low, although some terpenes (e.g. 3-carene) could be identified as fungal metabolites. On all materials, except gypsum board, the emission of aldehydes decreased during microbial growth. No low molecular weight carboxylic acids were identified.

Microorganisms are able to produce a wide variety of volatile organic compounds. This thesis deals with sampling, analysis and identification of such compounds, produced by microorganisms commonly found in buildings.

The volatiles were sampled on adsorbents and analysed by thermal desorption cold trap-injection gas chromatography, with flame ionization and mass-spectrometric detection. The injection was optimized, with respect to the recovery of adsorbed components and the efficiency of the chromatographic separation, using multivariate methods. Eight adsorbents were evaluated with the object of finding the most suitable for sampling microbial volatiles. Among the adsorbents tested, Tenax TA proved to have the best properties for the purpose. Some carbon-containing adsorbents, e.g., Tenax GR and Carbopack B, showed a catalytic effect on thermal decomposition of some compounds, mainly terpene derivatives.

Five fungal species, Aspergillus versicolor, Pénicillium commune, Cladosporium cladosporioides, Paecilomyces variotii and Phialophora fastigiata, and anactinomycete, Streptomyces albidoflavus, were cultivated on various artificial media and/or building materials. Cultivation was performed in culture flasks, provided with air inlet and outlet tubes. Humidified air was constantly led through the flasks, and samples were taken by attaching adsorbent tubes to the outlet tubes of the flasks. The cultivation medium proved to be of vital importance for metabolite production, quantitatively as well as qualitatively. For Streptomyces albidoflavus the effect of medium, cultivation temperature, and oxygen and carbon dioxide levels in the supplied air on the production of volatiles, was studied using multivariate techniques. The medium and the temperature exerted the largest influence, but the oxygen and carbon dioxide levels also affected the amounts of some metabolites produced.

The produced volatile metabolites were identified by mass spectrometry and reference compounds. Alcohols, ketones, sulphur compounds and terpenes were most frequently found, but hydrocarbons, ethers and esters were also produced by some species. Among the most commonly produced metabolites, which are also suggested as potential indicator substances for excessive growth of microorganisms in buildings, were 3-methyl-1-butanol, 2-methyl-1-butanol, 3-methyl-2-butanone, 3-methyl-2-pentanone, dimethyl disulphide, -methylfuran, 2,5-dimethylfuran and geosmin.