| 1. |
- Bugge, M. D., et al.
(författare)
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Reactive hyperemia and baseline pulse amplitude among smelter workers exposed to fine and ultrafine particles
- 2020
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 93, s. 399-407
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Ambient exposure to fine particles is associated with increased cardiovascular morbidity and mortality. Associations between occupational particulate matter (PM) exposure and cardiovascular disease have been studied less. The objective of this study was to examine associations between PM exposure and endothelial function among workers in Norwegian smelters. Methods: We examined endothelial function with Endo-PAT equipment after a working day (WD) and on a day off (DO) in 59 furnace workers recruited from three metal smelters in Norway. The difference in baseline pulse amplitude (BPA) and reactive hyperemia index (RHI) between the 2days was analysed in relation to individual exposure to PM < 250nm (PM250) or the respirable aerosol fraction of particles, and adjusted for relevant covariates. Results: The exposure to PM250 ranged from 0.004 to 5.7mg/m3. The mean BPA was significantly higher on WD relative to DO (772 vs. 535, p = 0.001). This difference was associated with PM concentrations among participants ≥ 34years, but not among the younger workers. Reactive hyperemia was significantly lower on workdays relative to days off (1.70 vs. 1.84, p = 0.05). This difference was observed only among participants above the age 34. No associations with PM exposure were observed. Conclusions: PM exposure was associated with higher BPA among participants older than 34years. BPA reflects microvessel pulsatility. Our results may indicate an age-dependent cardiovascular susceptibility to PM exposure. Endothelial function measured by RHI was reduced on WD among participants 34years and older, but we found no associations between PM exposure and RHI. © 2019, The Author(s).
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| 2. |
- Ellingsen, D. G., et al.
(författare)
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A study of atherothrombotic biomarkers in welders
- 2019
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 92:7, s. 1023-1031
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Studies have shown that welders have increased cardiovascular mortality. This may be due to airborne particulate matter (PM) exposure. Elevated levels of PM in polluted urban air have been associated with increased cardiovascular mortality and morbidity. This study seeks to explore potential mechanisms for the increased cardiovascular mortality in welders. Methods: Seventy welders were compared to 74 referents. Exposure to PM was assessed by personal full-shift sampling of work room air the last 2days before collection of blood samples. Selected biomarkers of pro-coagulant activity, endothelial/platelet activation and systemic inflammation were determined in the samples. Results: The welders had been occupationally exposed to PM for 15years on average. The geometric mean current exposure to PM was 8.1mg/m3. They had statistically significantly higher concentrations of TNF-α, P-selectin, CD40L, prothrombin fragment 1 + 2 and d-dimer than the referents. Increasing concentrations of d-dimer and CD40L were observed by increasing current exposure to PM. Discussion: The study shows that welders highly exposed to welding PM were in a pro-thrombotic state with increased thrombin generation and consequently higher d-dimer concentrations. The welders had also increased endothelial/platelet activation as compared to the referents. These alterations are compatible with increased cardiovascular mortality as previously reported among welders. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
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| 3. |
- Ellingsen, D. G., et al.
(författare)
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The variability of arsenic in blood and urine of humans
- 2023
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Ingår i: Journal of Trace Elements in Medicine and Biology. - 0946-672X. ; 78
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Tidskriftsartikel (refereegranskat)abstract
- Background: Humans are exposed to inorganic and organic arsenic. The total arsenic (As) concentration in urine is a commonly used biomarker of exposure. However, little is known about variability of As in biological fluids and the diurnal variation of As excretion.Objectives: Main objectives were to assess the variability of As in urine, plasma (P-As), whole blood (B-As), and the blood cell fraction (C-As), and to assess diurnal variation of As excretion. Methods: Six urine samples were collected at fixed times during 24 h on two different days around one week apart among 29 men and 31 women. Blood samples were collected when the morning urine samples were delivered. The intra-class correlation coefficient (ICC) was calculated as the ratio of the between-individuals variance to the total observed variance.Results: Geometric mean (GM) 24 h urinary excretions of As (U-As24 h) were 41 and 39 mu g/24 h on the two days of sampling. Concentrations of B-As, P-As and C-As were highly correlated with U-As24 h and As in first void morning urine. No statistically significant differences were observed for the urinary As excretion rate between the different sampling times. A high ICC was observed for As in the cellular blood fraction (0.803), while ICC for first morning urine corrected for creatine was low (0.316).Conclusions: The study suggests that C-As is the most reliable biomarker for use in exposure assessment of individual exposure. Morning urine samples have low reliability for such use. No apparent diurnal variation was observed in the urinary As excretion rate.
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| 4. |
- Eriksson, Janna, 1992, et al.
(författare)
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Urinary iodine excretion and optimal time point for sampling when estimating 24-h urinary iodine
- 2023
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Ingår i: British Journal of Nutrition. - : Cambridge University Press (CUP). - 0007-1145 .- 1475-2662. ; 130:8, s. 1289-97
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Tidskriftsartikel (refereegranskat)abstract
- Iodine deficiency may cause thyroid dysfunction. The iodine intake in a population is measured by urinary iodine concentration (UIC) in spot samples or 24-h urinary iodine excretion (24UIE). 24UIE is considered the gold standard and may be estimated using an equation including UIC, urinary creatinine concentration, sex and age (e24UIE). The aims of this study were to evaluate the preferable timing of UIC when using this equation and assess the variability of UIE. Sixty healthy non-smoking women (n 31) and men (n 29) were included in Gothenburg, Sweden. Twelve urine samples were collected at six fixed times on two separate days. Variability was calculated for UIC, 24UIE, e24UIE, iodine excretion per hour (iHr) and UIC adjusted for creatinine and specific gravity. Median 24UIE was 156 mu g/24 h and the median UIC (all spot samples) was 104 mu g/l. UIC (P < 0 center dot 001), 24UIE (P = 0 center dot 001) and e24UIE (P < 0 center dot 001) were significantly higher in men. e24UIE was relatively similar to 24UIE. However, when e24UIE was calculated from UIC in the first void, it was about 15 % lower than 24UIE (P < 0 center dot 001). iHr was lowest in the morning and highest in the afternoon. Median iHr was higher in men (7 center dot 4 v. 5 center dot 3 mu g/h, P < 0 center dot 001). The variability of UIE was higher within individuals than between individuals. This study suggests that most time points for estimation of individual 24UIE are appropriate, but they should preferably not be collected in the first void.
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| 5. |
- Sällsten, Gerd, 1952, et al.
(författare)
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Variability of lead in urine and blood in healthy individuals
- 2022
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351. ; 212
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lead is a non-essential toxic trace element. Lead in blood (BPb) is the most common biomarker of lead exposure but lead in urine (UPb) has also been used. There is, however, limited data on the variability of UPb in the general population and the association with BPb. Objectives: Our aims were to assess variability of lead in repeated blood and urine samples. The diurnal variation of UPb was also examined as well as associations with BPb. Methods: We established an openly available biobank including 60 healthy non-smoking individuals, 29 men and 31 women, 21–64 years of age (median 31 years), with repeated sampling of blood and urine. Timed urine samples were collected at six fixed time points in two 24 h periods, about one week apart, and adjusted for creatinine and specific gravity (SG). BPb and UPb were analyzed by inductively coupled plasma mass spectrometry. The within- and between-individual variabilities and intra-class correlation coefficients (ICCs; ratios of the between-individual to total observed variances) were calculated using mixed-effects models. Results: The ICCs for UPb samples were mostly above 0.5, when adjusted for creatinine or SG, and higher for overnight samples compared with daytime samples. The highest ICCs were obtained for BPb (ICC = 0.97) and for urine samples corrected for dilution by SG or creatinine. The ICC was 0.66 for overnight samples adjusted for creatinine. High correlations with BPb were found for 24 h UPb (rs = 0.77) and overnight samples, e.g. rs = 0.74 when adjusted for SG. There was diurnal variation of UPb with lowest excretion rate in overnight samples. There was also a significant association between the Pb excretion rate and urinary flow rate. Conclusions: In addition to BPb, UPb adjusted for creatinine or SG seems to be a useful biomarker for exposure assessment in epidemiological studies.
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