| 3. |
- Szidat, S., et al.
(författare)
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Intercomparison of 14C Analysis of Carbonaceous Aerosols : Exercise 2009
- 2013
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Ingår i: Radiocarbon. - : Cambridge University Press (CUP). - 0033-8222 .- 1945-5755. ; 55:2-3, s. 1496-1509
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Tidskriftsartikel (refereegranskat)abstract
- Radiocarbon analysis of the carbonaceous aerosol allows an apportionment of fossil and non-fossil sources of airborne particulate matter (PM). A chemical separation of total carbon (TC) into its subfractions organic carbon (OC) and elemental carbon (EC) refines this powerful technique, as OC and EC originate from different sources and undergo different processes in the atmosphere. Although C-14 analysis of TC, EC, and OC has recently gained increasing attention, interlaboratory quality assurance measures have largely been missing, especially for the isolation of EC and OC. In this work, we present results from an intercomparison of 9 laboratories for C-14 analysis of carbonaceous aerosol samples on quartz fiber filters. Two ambient PM samples and 1 reference material (RM 8785) were provided with representative filter blanks. All laboratories performed C-14 determinations of TC and a subset of isolated EC and OC for isotopic measurement. In general, C-14 measurements of TC and OC agreed acceptably well between the laboratories, i.e. for TC within 0.015-0.025 (FC)-C-14 for the ambient filters and within 0.041 (FC)-C-14 for RM 8785. Due to inhomogeneous filter loading, RM 8785 demonstrated only limited applicability as a reference material for C-14 analysis of carbonaceous aerosols. C-14 analysis of EC revealed a large deviation between the laboratories of 28-79% as a consequence of different separation techniques. This result indicates a need for further discussion on optimal methods of EC isolation for C-14 analysis and a second stage of this intercomparison.
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| 4. |
- Settimi, Laura, et al.
(författare)
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Cancer risk among female agricultural workers : a multi-center case-control study
- 1999
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Ingår i: American Journal of Industrial Medicine. - 0271-3586 .- 1097-0274. ; 36:1, s. 135-141
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundCancer risk among women engaged in farming has been poorly investigated. This group of female workers is of particular interest, however, since they may experience exposure to several potential agricultural hazards.MethodsA hospital-based case-control study was conducted in five Italian rural areas to examine the association between cancer and farming among women. The areas selected were located in three different regions (i.e., Piedmont, Tuscany, and Emilia-Romagna). The following cancer sites were selected for the study: stomach, colon, rectum, lung, skin melanoma, skin non-melanoma, breast, cervix and corpus uteri, ovary, bladder, kidney. Cases of non-Hodgkin's lymphoma were also included. Altogether, 1,044 newly diagnosed cases aged 20–75 years were ascertained from hospital records from March 1990 to September 1992, and for 945 of them detailed information was collected by a standard questionnaire. The analyses of data were performed comparing each case series to a reference group drawn from among the other sites. Unconditional logistic regression models were used in the statistical analyses.ResultsStatistically significant increased risks in association with farming were estimated for skin melanoma (OR 2.7, 95% CI 1.2–5.8) and bladder cancer (OR 2.7, 95% CI 1.2–6.1). Lung cancer was also found increased but not at a statistically significant level (OR 1.7, 95% CI 0.7–4.4). An OR lower than unity was observed for postmenopausal breast cancer (OR 0.4, 95% CI 0.3–0.7).ConclusionsThe present study suggests that women in farming might experience increased risk of cancers, not usually found in excess among male farmers, as well as a protective effect for postmenopausal breast cancer. The role of different patterns of exposure or gender specific responses should be considered in further studies.
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