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nÃo hà / A partir de dados mensais dos Ãndices de confianÃa de produtos alimentares e metalurgia da FGV, jà ajustados sazonalmente pela prÃpria instituiÃÃo, o presente trabalho avalia como a instabilidade econÃmica do perÃodo de 2002 a 2012 impactou nesses Ãndices. Foi selecionada uma amostra de 133 observaÃÃes, no referido perÃodo e Ãs duas variÃveis supracitadas foi aplicado um modelo autoregressivo com valor limite endÃgeno objetivando captar mudanÃas de regime na dinÃmica descrita pelos Ãndices de confianÃa jà citados, bem como de descrever o processo estocÃstico descrito pelas variÃveis selecionadas. Os indicadores qualitativos para essas variÃveis foram entÃo calculados e a metodologia permitiu investigar a linearidade e estacionaridade de suas trajetÃrias, produzindo resultados que revelaram as seguintes situaÃÃes para os Ãndices: i) o Ãndice de metalurgia apresentou uma dinÃmica nÃo linear e raiz unitÃria parcial com valor limite endÃgeno estimado de -5,94 pontos percentuais; ii) o Ãndice de produtos alimentares apresentou dinÃmica linear e estacionaridade da sÃrie. Em conjunto, tais constataÃÃes sugerem que a confianÃa do empresariado do seguimento de produtos alimentares, pertencente ao setor de consumo nÃo cÃclico, foi abalada em menor magnitude no perÃodo de instabilidade econÃmica que a confianÃa do empresariado do seguimento de produtos de metalurgia, pertencente ao setor de consumo cÃclico. Intuitivamente conclui-se que atravÃs da estimaÃÃo dos Ãndices que os referidos seguimentos tambÃm sofreram impactos de intensidades diferentes no contexto macroeconÃmico investigado. / From monthly data confidence indexes of food and metallurgy FGV, already seasonally adjusted by the institution itself, this study assesses how the economic instability of the period of 2002 to 2012 impacted these indexes. A sample of 133 observations was selected during that period to these two variables and an autoregressive model was applied with endogenous threshold value aiming to capture regime changes in the dynamics described by the confidence indices mentioned above, as well as describe the stochastic process described by the variables selected. The qualitative indicators for these variables were then calculated and the methodology allowed to investigate the linearity and stationarity of their trajectory, producing results that revealed the following situations for index: i) the index of metallurgy presented a nonlinear dynamic and partial unit root limit endogenous estimated -5.94 percentage points, ii) the index of food presented linear dynamics and stationarity of the series. Together, these findings suggest that the businessman confidence of following food products belonging to the consumer non-cyclic sector was shaken at a lower intensity in the period of economic instability that businessman confidence following the metallurgy products belonging to the sector consumer cyclic. Intuitively it is concluded that by estimating the indices that these segments also suffered impacts of different intensities in the macroeconomic context investigated.

Per- och polyfluorerade alkylsubstanser är framväxande syntetiska föroreningar som är spritt över alla ekosystem. Per- och polyfluorerade alkylsubstanser har fått ökad regulatoriska och allmän uppmärksamhet på grund av deras egenskaper av att vara persistenta, bioackumulerande i trofinnivåer och toxiska. Under år 2020 tog EU tillsammans med EFSA fram ett förslag för ett gränsvärde på ett tolerabelt veckointag på 4.4 ng/kg kroppsvikt för PFOA, PFOS, PFHxS och PFNA. Under de senaste decennierna har konsumenter efterfrågat alger i livsmedelsmarknaden på grund av algernas egenskaper av att vara hållbart, hälsosamt och naturligt. Alger har blivit en bild av en potentiell ersättare för animaliska livsmedelsprodukter. I denna studie analyserades PFAS i vildväxande bruna Saccharina Latissimi, i havsodlade och labbodlade gröna Ulva Fenestrate och i labbodlade röda Palmaria Palmata för att bedöma PFAS-halterna. Syftet var även att se över en potential risk för människor att överskrida EFSA:s gränsvärde. PFAS extraherades och analyserades via tekniken vätskekromatografi- tandem masspektrometri. Resultaten visade att PFAS förekommer i alger. Signifikanta skillnader av PFOA (0,082 ± 0,01 ng/g tv) och PFOS (0,284 ± 0,061 ng/g tv) uppmättes i Palmaria Palmata i jämförelse med Saccharina Latissimi och Ulva Fenestrate. Resultaten visade även att det möjligtvis kan finnas en risk att EFSA:s gränsvärde överskrids vid förtäring av Palmaria Palmata beroende på portionsstorlekar. Resultaten bidrar med grundförutsättningar för framtida forskningsbehov. För att kunna specificera vilka alger som är lämpliga för framtidens livsmedel och human konsumtion behöver det undersökas vidare i algernas egenskaper, odlingsmetoder och PFAS-halter i odlingsvatten.Nyckelord: PFAS, / Per- and polyfluorinated alkyl substances are emerging synthetic pollutants that are spread over all ecosystems. Per- and polyfluorinated alkyl substances have received increasing regulatory and general attention due to their properties of being persistent, bioaccumulative in trophine levels and toxic. In 2020, the EU, together with EFSA, produced a proposal for a limit value of a tolerable weekly intake of 4.4 ng/kg body weight for PFOA, PFOS, PFHxS and PFNA. In recent decades, the consumer has been in demand in the food market due to the algae's properties of being sustainable, healthy and natural. Algae have become an image of a potential substitute for animal food products. In this study, PFAS was analyzed in wild-growing brown Saccharina Latissimi, in sea-grown and lab-grown green Ulva Fenestrate and in lab-grown red Palmaria Palmata to assess PFAS levels. The purpose was also to review a potential risk for people to exceed the EFSA limit value. PFAS was extracted and analyzed by the liquid chromatography - tandem mass spectrometry technique. The results showed that PFAS occurs in algae. Significant differences in PFOA (0.082 ± 0.01 ng/g tv) and PFOS (0.284 ± 0.061 ng/g tv) were measured in Palmaria Palmata compared to Saccharina Latissimi and Ulva Fenestrate. The results also showed that there may be a risk that EFSA's limit value is exceeded when consuming Palmaria Palmata due to portion sizes. The results contribute with basic preconditions for future research needs. To be able to specify which algae are suitable for the food of the future and consumption for humans, it is necessary to further investigate the properties of the algae, cultivation methods and PFAS levels in cultivated water.

De nombreuses études de biométrologie sont menées à l’INRS, pour évaluer l’exposition professionnelle à des substances chimiques, en France, et pour compléter les connaissances en proposant des valeurs de références destinées à protéger des salariés exposés à ces substances. Ces études consistent à mesurer simultanément l’imprégnation biologique et l’exposition atmosphérique à une substance, chez des salariés exposés à celle-ci. La relation entre ces mesures biologiques et atmosphériques est ensuite estimée à travers un modèle de régression linéaire. Lorsque que cette relation existe et que la voie d’absorption du toxique est essentiellement inhalatoire, il est ensuite possible de dériver une Valeur Limite Biologique (VLB) à partir de la Valeur Limite d’Exposition Professionnelle (VLEP-8h) du toxique. Deux aspects de ces données ont été identifiés, qui ne sont pas ou seulement partiellement prises en compte dans les modélisations statistiques courantes : la censure due aux limites de détection (LD)/quantification (LQ) des mesures biologiques et atmosphériques et la variabilité inter-individuelle. Ignorer ces deux particularités lors de la modélisation mène à une perte de puissance statistique et à de potentielles conclusions biaisées. Les travaux menés dans le cadre de cette thèse ont permis d’adapter le modèle de régression à ces deux caractéristiques, dans un cadre bayésien. L’approche proposée repose sur la modélisation des mesures atmosphériques à l’aide de modèles à effets aléatoires prenant en compte les valeurs inférieures à la LD/LQ, et sur la modélisation simultanée des mesures biologiques, supposée être linéairement dépendantes sur une échelle logarithmique, de l'exposition atmosphérique, tout en tenant compte de la variabilité inter-individuelle. Ce travail a donné lieu à une publication scientifique dans une revue à comité de lecture. L’application de cette méthodologie a été réalisée sur des jeux d’exposition professionnelle au béryllium et au chrome, après avoir été cependant adaptée aux caractéristiques toxicocinétiques de ces deux substances. Il a ainsi été possible de proposer une VLB pour le béryllium (0,06 µg/g créatinine). L’exploitation de mesures de chrome dans deux secteurs d’activités différents (exposition professionnelle aux peintures de chromates, et exposition professionnelle dans le secteur du chromage électrolytique) a permis de mettre en évidence que le chrome urinaire dépend essentiellement de l’exposition au chrome VI, le chrome non VI ayant moins d’impact. Nous n’avons pas pu montrer de relation entre la solubilité du CrVI et le chrome urinaire. Une VLB de 0,41 µg/g créatinine, de l’ordre de la Valeur Biologique de Référence (VBR) proposée par l’ANSES (0,54 µg/g créatinine), a été estimée pour l’exposition professionnelle aux peintures de chromates, et une VLB de 1,85 µg/g créatinine a été estimée pour l’exposition professionnelle dans le secteur du chromage électrolytique, qui est en cohérence avec la VLB proposée par l’ANSES dans ce secteur, à savoir 1,8 µg/g créatinine / Many biomonitoring studies are conducted at INRS, in order to assess occupational exposure to chemicals in France, and to propose reference values to protect workers exposed to these substances. These studies consist in measuring simultaneously biological and airborne exposure of workers exposed to a toxic substance. The relationship between these biological and airborne measurements is then estimated through a linear regression model. When this relationship exists and the route of absorption of the toxic is essentially inhalatory, it is possible to derive a Biological Limit Value (BLV) from the Occupational Exposure Limit Value (OEL) of the toxic substance. However, two characteristics of these data have been identified, which are not or only partially taken into account in the current statistical modelling: the left-censoring due to limits of detection (LoD)/quantification (LoQ) of biological and airborne measurements, and the between-individual variability. Ignoring both of these features in modelling leads to a loss of statistical power and potentially biased conclusions. The work carried out in this thesis allowed us to adapt the regression model to these two characteristics, in a Bayesian framework. The proposed approach is based on the modelling of airborne measurements using random effects models adapted for values below the LoD / LoQ, and on the simultaneous modelling of biological measurements, assumed to depend linearly on a logarithmic scale, on the airborne exposure, while taking into account between-subject variability. This work resulted in a scientific publication in a peer-reviewed journal. This methodology has been applied on beryllium and chromium occupational exposure datasets, after adaptation to the toxicokinetic characteristics of these two substances. It has thus been possible to propose a BLV for beryllium (0.06 μg / g creatinine). The analysis of chromium measurements in two different sectors of activity (occupational exposure to chromate paints, and occupational exposure in the electroplating sector) made it possible to show that urinary chromium depends mainly on airborne exposure to VI chromium, non-VI chromium having less impact. We were not able to show a relationship between the solubility of airborne VI chromium and urinary chromium. A BLV of 0.41 μg / g creatinine, close to the Biological Guidance Value (BGV) proposed by ANSES (0.54 μg / g creatinine), was estimated for occupational exposure to chromate paints, and a BLV of 1.85 μg/g creatinine was obtained for occupational exposure in the electrolytic chromium plating sector, which is consistent with the ANSES proposed BLV in this sector, i-e 1.8 μg / g creatinine

Biomass energy is currently the largest renewable contributor to global energy supply and there is increasing demand for bioenergy feedstock. Consequently, the production of purpose-grown woody bioenergy crops, such as short rotation coppice (SRC) willow, is expected to proliferate. Although the economic and environmental benefits associated with SRC willow production are well documented, systematic assessments of nutrient cycling within these plantations are rare. The objective of this study was to examine biomass production and biogeochemical cycling of nitrogen (N), phosphorus (P), potassium (K), sulphur (S), calcium (Ca), and magnesium (Mg) during an initial four-year rotation of six willow varieties grown at four plantations along a 500 km north-south pedoclimatic gradient within Saskatchewan, Canada. Nutrient budgets were also calculated after quantifying various nutrient inputs (e.g., atmospheric deposition, soil mineral weathering, and organic matter mineralization), outputs (e.g., above- and below-ground biomass, leaching, and denitrification), and transfers (e.g., canopy exchange, leaf litter decomposition, and fine root turnover) affecting the plant available soil nutrient pool. Total stem, leaf litter, and below-ground (primarily fine roots) biomass production after four years averaged 19.0, 7.1, and 12.5 Mg ha-1, respectively, with corresponding soil nutrient budget deficits of 17, 39, 112, 271, and 74 kg ha-1 of N, P, K, Ca, and Mg, respectively, but a soil S surplus of 60 kg ha-1. Despite willow’s relatively low nutrient-demanding nature, negligible leaching and denitrification losses, and substantial nutrient cycling from leaf litter, the nutrient export in harvested biomass over multiple rotations will require soil nutrient amendments, particularly N and P, to maintain plantation productivity. Given the apparent eventual need for supplemental fertility to support adequate willow growth over the 22-yr plantation life span, the fate of broadcast 15N-labelled fertilizer was also examined. Though the willow accumulated less than ⅓ of the applied fertilizer N after one year, the majority of the residual fertilizer N (51%) remained available for willow uptake in subsequent years. Further research is needed to track the fate of applied fertilizers over multiple rotations to better understand fertilizer dynamics for optimizing SRC willow agronomy; thus helping to promote its viability as a biomass energy feedstock option.

Ventilation on demand (VOD) concept has earned significant worldwide attention by several mining companies in recent years. It is a concept where airflow is provided only to areas that require ventilation. The implementation of the concept has resulted in significant savings in annual energy consumption and cost for several companies globally. The research presented in this thesis sought to present the VOD system as an alternative solution and strategy to improve the ventilation system of Konsuln mine. The system is expected to cope with a planned increase in production rate and meet requirements in the new Swedish Occupational Health & Safety (OH&S) regulations, Arbetsmiljöverkets förtfattningssamling (AFS) 2018:1, which is based on the EU directive 2017/164 where Threshold Limit Value (TLV) for gases have been significantly reduced and provide safe work environment for workers in the mine. The thesis work started with planning and execution of a PQ (Pressure – Quantity) survey to calibrate the existing ventilation model of Konsuln mine. This was to ensure that the model is reasonably accurate to give reliable simulation predictions of the performance of Konsuln ventilation system in its current state and for the future. The good correlation between the modelled and underground measured values validated the model for further ventilation planning. The study further investigated and analyzed the current and future ventilation demand of LKAB test mine, Konsuln, to design a VOD system for its operations.The work outlined three main VOD design scenarios I, II, and III based on the proposed production plan, schedule, and the mining process that present the underground working conditions on the three main levels (436, 486 and 536) of Konsuln mine. Diesel, battery-powered, heat, and blast simulations were carried out for all the scenarios in the calibrated ventilation model using VentSim Design simulation software. The model was again used to estimate the annual ventilation power cost for the VOD scenarios to highlight the benefit and cost savings advantage under the VOD design system to deliver enough airflow quantity compared to the conventional system of ventilation. Simulation results showed that about 15.6% – 49.1% and 76.4% - 86.7% of significant cost savings will be achieved for diesel and battery-powered machineries respectively, while still supplying the needed amount of air to working areas to keep contaminants below their Threshold Limit Value -Time Weighted Average (TLV-TWA) and provide a good working environment. For additional benefits and savings of the Ventilation on Demand (VOD) system implementation, some considerations for equipment, personnel positioning and identification, monitoring system, and stations have also been discussed in this work.  These include; (i) Utilization of LKAB’s database system, Giron, in addition to mounting tags with unique IDs on machineries, to track the route of LHDs and trucks to deal with the challenge of airflow supply shortfall associated with auxiliary fans adjustment to affect target locations. (ii) Installation of temperature sensors, flow meters, gases and Diesel Particulate Matter (DPM) monitoring systems at specific, appropriate, and optimal locations in the mine for efficient implementation of the VOD system strategy. The heat simulations for both diesel and battery-powered machineries were carried out for the month of July when the highest temperatures in Kiruna are often recorded for the summer. They predicted the highest temperatures in working areas to be well below the limit used in Australia, 28°C Wet Bulb (WB). Four scenarios A, B, C and D were also considered for blast clearance time simulation using both the ramp and exhaust shaft. The blast simulation results indicated that the time to dilute and clear blast fumes through the exhaust shaft saves some clearance time compared to exhaustion through the ramp, although the shaft exhaustion will require additional financial commitment to purchase and install exhaust fans on each of the three main levels of the mine. Nevertheless, major ventilation work and practices such as removal of regulator in front of primary fans, additional radon measurement, and good auxiliary ventilation practices have been recommended to improve and actualize the benefits outlined in this work.

Kvartsdamm är ett arbetsmiljöproblem som kan leda till allvarliga konsekvenser för de exponerade yrkesarbetarna. De sjukdomar som ligger till följd för en hög exponering av kvartsdamm är framförallt silikos, KOL och lungcancer. Kvartsdammet uppstår då byggmaterial som innehåller kvartshaltigt material bearbetas, tillexempel betong. De små respirabla partiklarna av kvarts som uppstår vid bearbetningen bildar ärrvävnader i lungorna, vilket leder till att dem tappar sin kapacitet. Tidigare har krav ställts att arbetsplatserna ska utföra egna mätningar av kvarts, men inte längre. Nya författningssamlingen, AFS 2015:2 gör det möjligt för byggarbetsplatserna att använda sig av referensvärden och kringgå faktiska mätningar vid riskbedömningen av kvartsdamm. Examensarbetet redovisar några utav de hjälpmedel som används för en minskad exponering av dammet, där syftet är att hitta de största bristerna hos fallföretaget i byggproduktionen samt se hur den övergripande kunskapen ser ut på byggarbetsplatserna.Informationen till arbetet har samlats in från olika informationskällor, bland annat kvantitativa enkätundersökningar, semistrukturerade intervjuer samt informationssökning via internet där primärkällor prioriterats. Alternativa fakta har sorterats ut för en minskad avgränsning då examensarbetet enbart inriktar sig på den praktiska hanteringen av kvartsdamm.Examensarbetets resultat förväntas göra företagets riskbedömningsmall för kvartsdamm mer hanterbar genom den förenkling som tagits fram under arbetets gång. Diskussionerna har i huvudsak kretsat kring självkritisk bedömning av informationsinsamlingen samt hur utfallet av rapporten hade ändrats om fokus lades på andra delar vid arbetets början.Fallföretaget arbetar konstant med riskbedömning av kvarts för att uppnå en fullgod arbetsmiljö. En rotorsak var svårigheter kring just hanteringen av referensvärdena som gör att företaget inte använder riskbedömningsmallen som ett hjälpmedel. Då kvartsdamm ska bedömas i arbetsberedningarna är tanken att riskbedömningen som utförts i ett tidigare skede ska underlätta arbetet. Även kunskapen om kvartsdamm var varierande, där de anställda hos de större företagen har goda kunskaper medan de mindre underentreprenörerna har bristfälliga kunskaper. / Quartz dust is a health and safety problem that has serious consequences for the exposed workers. The diseases that are due to excessive exposure of silica are silicosis, COPD and lung cancer. The quartz dust occurs when building materials that containing quartz are processed, such as concrete. The small respirable quartz dust particles that occur during processing form scar tissues in the lungs, causing them to lose their capacity. In the past, demands have been made that workplaces should carry out their own measurements of quartz, but no longer. The new regulation, AFS 2015:2, enable construction sites to use benchmarks and circumvent actual measurements in the risk assessment of quartz dust. The study reports some of the tools used to reduce exposure to the dust, where the purpose is to find the biggest shortcomings of the case company in the construction production and see how the overall knowledge looks at the construction sites.The information for the work has been collected from various sources of information, including quantitative surveys, semi structured interviews and information retrieval via the Internet where primary sources have been prioritized. Alternative facts have been sorted out for a reduced demarcation as the degree project focuses solely on the practical handling of quartz dust. The discussion mainly revolved around self-critical assessment of information gathering. The discussion has also investigates how the outcome of the report have been changed if the focus had been other parts at the start of work.The case the company is constantly working with risk assessment of quartz to achieve an acceptable working environment. A isolating was a problem in dealing with the reference values, which means that the company does not use the risk assessment template as an aid. When quartz dust is to be assessed in the working preparations, the idea is that the risk assessment template facilitates the work. The knowledge of quartz dust was also variable, where the employees of the larger companies had good knowledge while the smaller subcontractors had inadequate knowledge.