International Archives of Occupational and Environmental Health

Ikeda, Masayuki; Shimbo, Shinichiro; Watanabe, Takao; Yamagami, Takashi

doi: 10.1007/s00420-005-0069-0pmid: 16408194

Objective: The objective of this study is to examine if overall correlation exists among cadmium levels (Cd) in the general environment, dietary Cd intake, and Cd body burden of local residents. Methods: Eleven prefectures in Japan were selected as the areas where large-scale data on Cd levels in urine of adult women (40–49 and 50–59 years of age, respectively) were available to calculate geometric mean (GM) values for each of the prefecture. Other data were cited from published or previously established databases on Cd in the sediments of river bottoms (as a representative of Cd in the environment), Cd in rice for local consumption, and Cd in daily food duplicate samples collected from local women populations, and calculated for GM values for the prefectures. The GM values were subjected to correlation matrix and regression analysis. Results: Marginally significant (P<0.10) correlation was detected between Cd in sediment and Cd in rice. Furthermore, correlation of Cd in sediment was significant with Cd in total foods (P<0.05) and possibly with Cd in urine (P<0.05–0.10). Importance of data on Cd in rice paddy soil as a missing link is discussed. Conclusions: Correlation was demonstrated in the flow of Cd transport from the environment (expressed as Cd contents in river sediments) to humans (in terms of Cd in urine) among general populations in Japan.

Barbinova, L.; Baur, X.

doi: 10.1007/s00420-005-0051-xpmid: 16421715

The objective of this study was to evaluate the role of eNO changes post inhalative isocyanate challenge tests (ΔeNO) with regard to specific asthmatic reactions and unspecific bronchial hyperresponsiveness (BHR) to predict clinical and subclinical responses of isocyanate workers. Methods: 55 workers with isocyanate-related respiratory complaints (29 with BHR and 25 without BHR) underwent occupational-type challenge tests. We determined eNO before, during and up to 22 h after diagnostic isocyanate challenge. Results: The 12 asthmatic responders (22%) in the isocyanate-challenge test showed the highest eNO changes 22 h after challenge as well as a significant association between these changes and BHR. There was a positive association between an eNO increase of >50% and an asthmatic response when compared to nonresponders with an odds ratio of 6.1; 95% CI 1.4–26.3; P=0.02. More than half of the employees with BHR (52%) but only 20% of those without BHR developed an eNO rise of >50% after 22 h. Furthermore, a significant positive association was found between the combination of BHR plus eNO increase of 50% after 22 h and the maximum sRaw change (% of baseline value) during the period 0–22 h after isocyanate exposure. The combination of BHR and eNO increase of >50% was also associated with clinical symptoms during specific challenge tests (cough, shortness of breath, and/or rhinitis). Discussion and conclusions: An eNO increase 22 h post isocyanate challenge occurred in two-thirds of responders and in approximately half of nonresponders with BHR but only rarely in those without BHR. The combination of BHR and eNO increase in nonresponders may offer a new diagnostic tool to register subjects with an increased risk of developing occupational asthma. However, a large study group to perform follow-up investigations into this topic would be helpful to emphasize the importance of this finding.

Wilkinson, Simon; Maas, Wilfred; Nielsen, Jesper; Greaves, Laura; Sandt, Johannes; Williams, Faith

doi: 10.1007/s00420-005-0056-5pmid: 16435152

Objectives: To determine the effect of skin thickness on the percutaneous penetration and distribution of test compounds with varying physicochemical properties using in vitro systems. Studies were carried out in accordance with OECD guidelines on skin absorption tests. Methods: Percutaneous penetration of caffeine (log P −0.01), testosterone (log P 3.32), propoxur (log P 1.52) (finite dose in ethanol to water vehicle ratio) and butoxyethanol (log P 0.83) (undiluted finite dose or as an infinite dose 50% [v/v] aqueous solution) through skin of varying thicknesses under occluded conditions was measured using flow through cells for 8–24 h. Saline (adjusted to pH 7.4) was used as receptor fluid, with BSA added for studies with testosterone and propoxur. Following exposure, the remaining surface dose was removed by swabbing and the skin digested prior to scintillation counting. Results: The maximum flux of caffeine was increased with decreasing skin thickness, although these differences were found to be non-significant. The presence of caffeine in the skin membrane was not altered by skin thickness. Maximum flux and cumulative dose absorbed of testosterone and butoxyethanol (in both finite and infinite doses) were markedly reduced with full thickness (about 1 mm thick) skin compared with split thickness skin (about 0.5 mm). Maximum flux of propoxur (dissolved in 60% ethanol) was clearly higher through skin of 0.71 mm than through skin of 1.36 mm, but no difference was found between 0.56 and 0.71 mm. The proportion of propoxur present in the membrane after 24 h increased significantly over the complete range of thicknesses tested (0.56–1.36 mm). Conclusions: A complex relationship exists between skin thickness, lipophilicity and percutaneous penetration and distribution. This has implications for risk assessment studies and for the validation of models with data from different sources.

Voelter-Mahlknecht, S.; Krummenauer, F.; Koulele, D.; Mahlknecht, U.; Escobar Pinzón, L.; Dupuis¹, H.; Letzel, S.

doi: 10.1007/s00420-005-0070-7pmid: 16397800

Objectives: In order to establish an international standard of cold provocation test in the assessment of vibration-induced white finger (VWF) disease, an ISO-working group tentatively created the DIN ISO 14835-1. Based on this new standard, previously existing testing conditions had to be modified. Since a comparison of current and previous evaluation procedures is necessary for both the individual assessment and the performance of metaanalyses, the revision and validation of criteria for the examination of the cold provocation tests are appropriate and necessary. Methods: Twenty-one individuals suffering from VWF disease whose disorder was accepted as an occupational disease underwent the cold provocation test on two successive days following a 2- and a 5-min-long exposure to the cold. As a benchmark for classification as ‘normal’ or ‘pathological’, the 15-min mark after a 2-min-long exposure was chosen. A skin temperature of 28°C was selected for discrimination between ‘non-pathological’ (at least 28°C) and ‘pathological’ test results. Results: It could be shown, that exposures to cold water (12°C) over 2 and 5 min lead to similar rewarming profiles, who differ in median systematically by 1°C. A modification of the former classification rule should be considered. After a 5 min exposure, the classification criterion can be based on the temperature assessments measured after 20 min; alternatively the cut point can be reduced from 28 to 27°C while maintaining the previous assessment time of t=15 min. Conclusions: The shown results represent the first attempt of modifying the previous classification criteria of the cold provocation test within the scope of the VWF disease. In view of the described problems of the study design there is no doubt that continuing modifications and their validation on the base of larger collectives groups are necessary.