Iron Absorption during Iron Supplementation in Blood Donors

The total amount of iron absorbed from a total supplementation of 2000 mg of iron was studied after a blood donation. 10 regular blood donors and 10 subjects without previous blood loss were included in the study. No subject had received any iron treatment before the investigation. Both groups were given one sustained release tablet containing 100 mg of iron as Fe SO₄ once daily for 20 days. The iron in these tablets was labelled with ⁵⁹Fe. The total amount of iron absorbed from the tablets was measured by a whole body counting technique. Laboratory tests including haematological data, desferrioxamine tests and sternal marrow punctures were made before and after the iron treatment. The non-donors lost a mean amount of 215 mg iron by phlebotomy and the total iron absorption from the tablets was only 94 mg (4.7%). In the regular blood donors the corresponding iron loss was 276 mg and the absorption was 280 mg (14%). The iron supplementation given in this study covered the iron losses in the regular blood donors but not in the non-donors. This iron prophylaxis will prevent a depletion but not a reduction of the iron stores in blood donors with high donation frequency.     

One hundred eighteen Bristow-Latarjet repairs for recurrent anterior dislocation of the shoulder prospectively followed for fifteen years: study II-the evolution of dislocation arthropathy

Dislocation arthropathy after surgical treatment of recurrent anterior dislocation of the shoulder has been a subject of discussion over the years. The objective of this prospective study was to evaluate the Bristow-Latarjet repair at 2 and 15 years after surgery with respect to arthropathy and to evaluate factors responsible for this development. At 2 and 15 years after a Bristow-Latarjet repair for recurrent anterior dislocation, we prospectively analyzed the radiographs of 115 of 118 shoulders. The majority of the patients also had radiography of the nonindex shoulder (111/118). Dislocation arthropathy was found on ordinary anteroposterior views in 46 of 115 shoulders (mild in 39, moderate in 5, and severe in 2). The anteroposterior view angulated 45 degrees from above gave the best visualization of the humeral osteophyte and, together with the axial view, doubled the incidence of moderate and severe arthropathy at follow-up (mild in 40, moderate in 11, and severe in 5). Of 38 shoulders with a postoperative position of the transferred coracoid process 2 to 4 mm medial to the glenoid rim and the screw and transplant parallel to the glenoid, 3 had moderate arthropathy (8%) compared with 8 shoulders with moderate arthropathy and 5 with severe arthropathy out of 77 shoulders with a nonoptimal position of the coracoid (17%) (P = not significant). The degree of restriction of outward rotation at 2 years did not influence the degree of arthropathy after 15 years. Global assessment of the operative result was not related to arthropathy at follow-up. When the first dislocation occurred before age 23 years, the incidence of arthropathy was significantly lower than when it occurred in age 23 years or older (P = .006). When all views were included, moderate or severe dislocation arthropathy was found in 14% of the shoulders, and a further 35% had mild arthropathy. When follow-up studies of operated series of shoulder dislocations with the Bristow-Latarjet method are done, it is important to have the same radiologic views to compare the incidence of dislocation arthropathy correctly.     

Measuring dust on skin with a small vacuuming sampler--a comparison with other sampling techniques

Airborne skin exposure to allergens and irritants may cause dermatitis. There are few methods for assessing skin exposure to airborne particles. We have modified and tested a vacuuming sampler for removing particles from the skin. The sampler was compared with two other skin and surface exposure sampling techniques. These were based on surrogate skin (a patch sampler-adhesive tape on an optical cover glass) and a tape stripping removal procedure. All three samplers measure the mass of dust on skin. Dust containing starch was deposited onto the skin in a whole-body exposure chamber. Samples were taken from forearms and shoulders and analysed using optical microscopy. With the different sampling techniques small differences in the results were obtained. Agreement between the vacuuming sampler and the tape stripping technique was good. The comparison between patch and tape stripping procedure indicated a slight overestimation for the patch. The three techniques are applicable for assessing skin exposure to particles and for dose-effect studies. The vacuuming method will be further developed and applied in workplace studies. The technique allows for dust sampling from large areas of skin.     

Large organic aerosols in a dynamic and continuous whole-body exposure chamber tested on humans and on a heated mannequin

Exposure to large airborne organic aerosols may cause respiratory and skin symptoms. The use of human exposure chambers permits safe mechanistic studies of the effect of inhalation or dermal deposition of such particles. The performance of a dynamic and continuous whole-body human exposure chamber using turbulent air mixing during exposure to these organic aerosols of humans and of a new heated mannequin was evaluated. Variability of temporal and spatial distribution of the airborne particle concentration, and aerodynamic aerosol size distribution of the inhalable fraction, were evaluated. The temporal and spatial distribution of these aerosols close to the breathing zone during an exposure session was typically < or = 10%, which is low for airborne particles of this size. In a larger section around a human, only slightly higher spatial variation was found. Variability between exposure sessions was also low (< 10%). Only limited effect of relative humidity for the organic aerosols was observed. The aerodynamic particle size distribution curves differed slightly, but some were comparable to those in occupational environments. The outcome of the performance tests as measured with the heated mannequin was almost the same as with humans, indicating that the mannequin could be used in preparatory tests in this type of chamber.     

Case-control study of the association between the use of cellular and cordless telephones and malignant brain tumors diagnosed during 2000-2003

We performed a case-control study on the use of cellular and cordless telephones and the risk for brain tumors diagnosed during 2000-2003. We report the results for malignant brain tumors with data from 317 cases (88%) and 692 controls (84%). The use of analog cellular phones yielded odds ratio (OR) of 2.6 and a 95% confidence interval (CI) of 1.5-4.3, increasing to OR=3.5 and 95% CI=2.0-6.4 with a >10-year latency period. Regarding digital cellular telephones, the corresponding results were OR=1.9, 95% CI=1.3-2.7 and OR=3.6, 95% CI=1.7-7.5, respectively. Cordless telephones yielded OR=2.1, 95% CI=1.4-3.0, and with a >10-year latency period, OR=2.9, 95% CI=1.6-5.2. The OR increased with the cumulative number of hours of use and was highest for high-grade astrocytoma. A somewhat increased risk was also found for low-grade astrocytoma and other types of malignant brain tumors, although not significantly so. In multivariate analysis, all three phone types studied showed an increased risk.     

Sinonasal cancer and occupational exposures: a pooled analysis of 12 case–control studies

Objective: In order to examine the associations between sinonasal cancer and occupational exposures other than wood dust and leather dust, the data from 12 case–control studies conducted in seven countries were pooled and reanalyzed. Methods: The pooled data set included 195 adenocarcinoma cases (169 men and 26 women), 432 squamous cell carcinomas (330 men and 102 women), and 3136 controls (2349 men and 787 women). Occupational exposures to formaldehyde, silica dust, textile dust, coal dust, flour dust, asbestos, and man-made vitreous fibers were assessed with a job-exposure matrix. Odds ratios (ORs) were adjusted for age, study, wood dust, and leather dust, or other occupational exposures when relevant. 95% confidence intervals (CIs) were estimated by unconditional logistic regression. Results: A significantly increased risk of adenocarcinoma was associated with exposure to formaldehyde. The ORs for the highest level of exposure were 3.0 (CI = 1.5–5.7) among men and 6.2 (CI = 2.0–19.7) among women. An elevated risk of squamous cell carcinoma was observed among men (OR = 2.5, CI = 0.6–10.1) and women (OR = 3.5, CI = 1.2–10.5) with a high probability of exposure to formaldehyde. Exposure to textile dust was associated with non-significantly elevated risk of adenocarcinoma, among women only: the OR for the high level of cumulative exposure was 2.5 (CI = 0.7–9.0). High level of asbestos exposure was associated with a significantly increased risk of squamous cell carcinoma among men (OR = 1.6, CI = 1.1–2.3). Conclusions: The results of this pooled analysis support the hypothesis that occupational exposure to formaldehyde increases the risk of sinonasal cancer, particularly of adenocarcinoma. They also indicate an elevated risk of adenocarcinoma among women exposed to textile dust, and suggest that exposure to asbestos may increase the risk of squamous cell carcinoma.     

Exposure to pesticides as risk factor for non-Hodgkin's lymphoma and hairy cell leukemia: pooled analysis of two Swedish case-control studies

Increased risk for non-Hodgkin's lymphoma (NHL) following exposure to certain pesticides has previously been reported. To further elucidate the importance of phenoxyacetic acids and other pesticides in the etiology of NHL a pooled analysis was performed on two case-control studies, one on NHL and another on hairy cell leukemia (HCL), a rare subtype of NHL. The studies were population based with cases identified from cancer registry and controls from population registry. Data assessment was ascertained by questionnaires supplemented over the telephone by specially trained interviewers. The pooled analysis of NHL and HCL was based on 515 cases and 1141 controls. Increased risks in univariate analysis were found for subjects exposed to herbicides (OR 1.75, CI 95% 1.26-2.42), insecticides (OR 1.43, CI 95% 1.08-1.87), fungicides (OR 3.11, CI 95% 1.56-6.27) and impregnating agents (OR 1.48, CI 95% 1.11-1.96). Among herbicides, significant associations were found for glyphosate (OR 3.04, CI 95% 1.08-8.52) and 4-chloro-2-methyl phenoxyacetic acid (MCPA) (OR 2.62, CI 95% 1.40-4.88). For several categories of pesticides the highest risk was found for exposure during the latest decades before diagnosis. However, in multivariate analyses the only significantly increased risk was for a heterogeneous category of other herbicides than above.