OBJECTIVES: The effects of occupational and leisure-time exposures on the risk of acute myeloid leukemia (AML) were investigated with emphasis on clonal chromosome aberrations (CCA) and morphological subtypes. METHODS: Consecutively diagnosed cases of AML (N=333) and 1 population referent per case were retrospectively included in the study. Information on worktasks, companies, and leisure-time activities was obtained with telephone interviews. Exposure probability and intensity were assessed by occupational hygienists. Associations were evaluated with logistic regression. RESULTS: Exposure to organic solvents was associated with an increased risk of AML [low exposure: OR 1.5 (95% confidence interval (95% CI) 1.0-2.3, moderate-high exposure: OR 2.3 (95% CI 1.0-5.0)]. For exposure to solvents, but not to benzene, the OR was 1.2 (95% CI 0.69-2.0) for "low" and 2.7 (95% CI 1.0-7.3) for "moderate-high" exposure. The observed effects increased with intensity and duration of exposure. The estimated effects were higher for patients >60 years of age at the time of diagnosis. The effect of exposure to organic solvents was not differential with regard to morphology [except possibly erythroleukemia: OR 4.2, 95% CI 1.0-17 or the presence of CCA in general]. No increased risk for AML with complex CCA or with total or partial losses of chromosomes 5 or 7 were observed, but a higher risk was found for AML with trisomy 8 (OR 11, 95% CI 2.7-42) as the sole aberration. CONCLUSIONS: Exposure to organic solvents was associated with an increased risk of AML. This association was not due to benzene exposure alone and may be modified by age. Furthermore, specific associations with trisomy 8, and possibly also erythroleukemia, were suggested.
The Swedish Navy has operated submarines equipped with air independent propulsion for two decades. This type of submarine can stay submerged for periods far longer than other non-nuclear submarines are capable of. The air quality during longer periods of submersion has so far not been thoroughly investigated. This study presents results for a number of air quality parameters obtained during more than one week of continuous submerged operation. The measured parameters are pressure, temperature, relative humidity, oxygen, carbon dioxide, hydrogen, formaldehyde and other volatile organic compounds, ozone, nitrogen dioxide, particulate matter and microbiological contaminants. The measurements of airborne particles demonstrate that air pollutants typically occur at a low baseline level due to high air exchange rates and efficient air-cleaning devices. However, short-lived peaks with comparatively high concentrations occur, several of the sources for these have been identified. The concentrations of the pollutants measured in this study do not indicate a build-up of hazardous compounds during eight days of submersion. It is reasonable to assume that a substantial build-up of the investigated contaminants is not likely if the submersion period is prolonged several times, which is the case for modern submarines equipped with air independent propulsion.
Justification of the methodological approach to evaluating effectiveness of the countermeasure strategies in agricultural production on contaminated territories is provided. The results from a comparative analysis of strategies for protective measures in agriculture after the Chernobyl NPP accident are presented. The time between radioactive fallout and application of countermeasures is shown to be one of the main factors responsible for effectiveness of countermeasures applied.
A model representing the bioaccumulation of persistent organic pollutants (POPs) in arctic terrestrial mammalian food-chains is developed, parametrized, tested, and analyzed. The model predicts concentrations of POPs in lichen, caribou (Rangifer tarandus), and wolf (Canis lupus) food-chains of Canada's central and western arctic region from measured concentrations in air and snowpack meltwater. The model accounts for temporal and seasonal variation in diet composition, life-stage, body weight, and fat content over the life-span of the animal. Model predicted concentrations of 25 organic chemicals forecasted for caribou and wolves from Cambridge Bay (69 degrees 07' N 105 degrees 03' W), Inuvik (68 degrees 18' N 133 degrees 29' W) and Bathurst Inlet (64 degrees 15' N 113 degrees 07' W) are shown to be in good agreement with the observed data. The model illustrates a strong relationship between biomagnification factors and chemical K(OA) and illustrates the effect of age, sex, and temperature on POPs bioaccumulation. Model results show that POPs with K(OA)s 5 and also exhibit a log K(OW) > 2, show significant bioaccumulation in arctic terrestrial food-chains. The model shows that persistent low K(OW) (K(OW)s
Distinguishing between effects of natural and anthropogenic environmental factors on ecosystems is a fundamental problem in environmental science. In river systems the longitudinal gradient of environmental factors is one of the most relevant sources of dissimilarity between communities that could be confounded with anthropogenic disturbances. To test the hypothesis that in macroinvertebrate communities the distribution of species' sensitivity to organic toxicants is independent of natural longitudinal factors, but depends on contamination with organic toxicants, we analysed the relationship between community sensitivity SPEAR(organic) (average community sensitivity to organic toxicants) and natural and anthropogenic environmental factors in a large-scale river system, from alpine streams to a lowland river. The results show that SPEAR(organic) is largely independent of natural longitudinal factors, but strongly dependent on contamination with organic toxicants (petrochemicals and synthetic surfactants). Usage of SPEAR(organic) as a stressor-specific longitude-independent measure will facilitate detection of community disturbance by organic toxicants.
This phase I study was performed to evaluate the safety, tolerability, and efficacy of the oral matrix metalloproteinase inhibitor BAY 12-9566 in combination with 5-fluorouracil/leucovorin in patients with advanced solid tumours, and to identify the maximum tolerated dose and the dose for use in future studies.
BAY 12-9566 and 5-fluorouracil/leucovorin were administered to 17 patients in 3 cohorts. Each patient served as his/her own control, with 5-fluorouracil being given alone on days 1-5 of cycle 1. In cohort 1, BAY 12-9566 at 800 mg p.o. b.i.d. was given with 350 mg/m2 5-fluorouracil/20 mg/m2 leucovorin x 5 days q28 days. In cohort 2, the BAY 12-9566 dose was reduced to 400 mg p.o. b.i.d., with the 5-fluorouracil/leucovorin doses remaining unchanged. Finally, in cohort 3, BAY 12-9566 400 mg bid was given with 5-fluorouracil 400 mg/m2/day. Patients were continued on therapy until unacceptable toxicity or tumour progression occurred. Pharmacokinetic analyses for both BAY 12-9566 and 5-fluorouracil were performed.
The maximum tolerated dose was 400 mg p.o. b.i.d. BAY 12-9566 plus 5-fluorouracil/leucovorin at 400 mg/m2/day and 20 mg/m2/day, respectively. Thrombocytopenia necessitated a decrease of the dose of BAY 12-9566 by 50% from cohort 1 to cohort 2. Two dose-limiting toxicities occurred in cohort 3 consisting of neutropenic fever, and ileitis, causing severe diarrhea. Of 17 patients treated on study, 7 of 14 patients evaluable for response achieved stable disease. Pharmacokinetic analysis suggested there was no interaction between BAY 12-9566 and 5-fluorouracil.
BAY 12-9566 400 mg bid and 5-fluorouracil 350 mg/m2 plus leucovorin 20 mg/m2 can be co-administered. Although there is some evidence of a clinical interaction, there is no apparent pharmacokinetic interaction. Future studies with these 2 types of agents administered in combination are warranted.
Aquatic taste and odor (T/O) is rarely produced by toxic contaminants or pathogens; nevertheless, it has major negative impacts on the public and the drinking-water industry. Consumers use T/O as a primary measure of drinking water safety, yet this criterion is poorly understood, and its origins and triggers often go untraced. Much surface-water T/O is produced by the increased production of volatile organic compounds (VOCs) by algae. These chemicals can be symptomatic of short-term problems with source, treatment, or distribution systems. At a broader level, they can signify fundamental changes in aquatic ecosystems induced by human activity. T/O varies in chemistry, intensity, and production patterns among different algal taxa, and is often linked with excessive algal growth and/or the invasion of noxious species. Some VOCs may signal the presence of potentially toxic algae and/or other associated water quality issues. Traditionally, T/O has been linked with the widespread eutrophication of many surface waters; however, there has been a recent growth in the number of T/O events reported in oligo-mesotrophic systems, for example, the Glenmore Reservoir (Calgary AB) and the Laurentian Great Lakes. From a management and public perspective, therefore, it is vitally important to monitor T/O, and to continue to work toward a better understanding of the proximal and the ultimate causes-which VOCs and algae species are involved. In the short term, odor events could be anticipated and water treatment optimized. In the long term, this approach would contribute toward more a robust management of this resource through remedial or preventative measures.
University of Applied Sciences Hamburg, Department of Environmental Engineering, Ulmenliet 20, 21033 Hamburg, Germany; Institute of Biomedical and Environmental Health Research, School of Science & Sport, University of the West of Scotland, Paisley Campus, Paisley PA 1 2BE, United Kingdom. Electronic address: email@example.com.
Sediment cores and bottom water samples from across the Baltic Sea region were analyzed for freely dissolved concentrations (Cfree), total sediment concentrations (CT) and the dissolved aqueous fraction in water of seven indicator PCBs. Ex-situ equilibrium sampling of sediment samples was conducted with polydimethylsiloxane (PDMS) coated glass fibers that were analyzed by automated thermal desorption GC-MS, which yielded PCB concentrations in the fiber coating (CPDMS). Measurements of CPDMS and CT were then applied to determine (i) spatially resolved freely dissolved PCB concentrations; (ii) baseline toxicity potential based on chemical activities (a); (iii) site specific mixture compositions; (iv) diffusion gradients at the sediment water interface and within the sediment cores; and (vi) site specific distribution ratios (KD). The contamination levels were low in the Gulf of Finland and moderate to elevated in the Baltic Proper, with the highest levels observed in the western Baltic Sea. The SPME method has been demonstrated to be an appropriate and sensitive tool for area surveys presenting new opportunities to study the in-situ distribution and thermodynamics of hydrophobic organic chemicals at trace levels in marine environments.