Search results for "Environmental monitoring"
showing 10 items of 609 documents
Application of headspace solid phase dynamic extraction gas chromatography/mass spectrometry (HS-SPDE-GC/MS) for biomonitoring of n-heptane and its m…
2011
Abstract Solid phase dynamic extraction (SPDE) is an innovative sample preparation and enrichment technique in connection with gas chromatography (GC). Using SPDE, we developed a method for simultaneous determination of n-heptane and its mono-oxygenated metabolites heptane-4-one, 3-one, 2-one, 4-ol, 3-ol, 2-ol, and 1-ol in blood. After adjustment of various extraction and desorption parameters, method validation resulted in limits of detection (LOD) between 0.006 (heptane-4-one) and 0.021 mg/L (heptane-1-ol). Intra-assay coefficients of variation ranged between 4.8% and 20.8% while relative recovery ranged between 100% and 117% (spiked concentration 0.128 mg/L, n = 8). The method was appli…
The long-term effects of rally driving on spinal pathology
2000
Abstract Objectives. To investigate the consequences of rally driving on lumbar degenerative changes. Background. Vehicular driving is suspected to accelerate disc degeneration through whole-body vibration, leading to back problems. However, in an earlier well-controlled study of lumbar MRI findings in monozygotic twins, significant effects of lifetime driving on disc degeneration were not demonstrated. Another study of machine operators found only long-term exposure to vibration on unsprung seats led to a reduction in disc height. Design. Case-control study comparing rally drivers with population sample. Methods. Eighteen top rally drivers and co-drivers, mean age 43 yrs (SD, 10), voluntee…
Modelling the non-linear multiple-lag effects of ambient temperature on mortality in Santiago and Palermo: a constrained segmented distributed lag ap…
2008
Objectives: Exposure to ambient temperature can affect mortality levels for days or weeks following exposure, making modelling such effects in regression analysis of daily time-series data complex. Methods: We propose a new approach involving a multi-lag segmented approximation to account for the non-linear effect of temperature and the use of two different penalised spline bases to model the distributed lag of both heat and cold exposure. Compared with standard splines, the novel penalised framework is more flexible at short lags where change in coefficients is greatest, and selection of the maximum lag appears substantially less important in determining the overall pattern of the effect. …
Estimated radiation exposure of German commercial airline cabin crew in the years 1960-2003 modeled using dose registry data for 2004-2015.
2016
Exposure to ionizing radiation of cosmic origin is an occupational risk factor in commercial aircrew. In a historic cohort of 26,774 German aircrew, radiation exposure was previously estimated only for cockpit crew using a job-exposure matrix (JEM). Here, a new method for retrospectively estimating cabin crew dose is developed. The German Federal Radiation Registry (SSR) documents individual monthly effective doses for all aircrew. SSR-provided doses on 12,941 aircrew from 2004 to 2015 were used to model cabin crew dose as a function of age, sex, job category, solar activity, and male pilots' dose; the mean annual effective dose was 2.25 mSv (range 0.01–6.39 mSv). In addition to an inverse …
Serum concentrations of persistent organic pollutants (POPs) in the inhabitants of a Sicilian city.
2012
Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems. OBJECTIVES: To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily. METHODS: A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry. RESULTS: HCB, p…
Exposure to nitroaromatic explosives and health effects during disposal of military waste.
2003
To investigate the exposure to dinitrotoluene (DNT) and trinitrotoluene (TNT) and the resulting effects in workers which occur during the disposal of military waste.Eighty two employees from a mechanical plant in Germany were studied, of whom 51 were regularly exposed to ammunition containing TNT and DNT, 19 occasionally, and 12 not at all.Air analyses yielded maximum concentrations of 20 micro g/m(3) for 2,4-DNT and 3250 micro g/m(3) for 2,4,6-TNT, respectively. The maximum concentrations in the urine of workers regularly exposed amounted to 5.0 micro g/l of 2,4,6-TNT, 1464.0 micro g/l of 2-amino-4,6-dinitrotoluene, 6693.0 of micro g/l 4-amino-2,6-dinitrotoluene, 2.1 micro g/l of 2,4-DNT, …
Urinary levels of enniatin B and its phase I metabolites: First human pilot biomonitoring study
2018
Abstract Enniatins (Enns) are mycotoxins produced by Fusarium spp. and are widely distributed contaminants of cereals and derivate products. Among the different identified enniatins, Enn B is the most relevant analogue in cereals in Europe. Therefore, the aim of this study was to investigate for the first time the occurrence of Enn B and Enn B phase I metabolites in 300 human urine samples throughout an ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) methodology. Three different sample preparation procedures were evaluated and salting-out liquid-liquid extraction showed satisfactory validation results. Enn B was quantified in 83.7% of sa…
External and internal exposure of wine growers spraying methyl parathion.
2005
Organophosphates, used in agriculture, are readily absorbed through the skin. We investigated the relationship between dermal and inhalative methyl parathion exposure and the plasma levels. Twenty-three healthy wine growers sprayed the insecticide for 50 min. Fluorescent brilliant sulfoflavin was added to the spraying fluids and filter papers were fixed on the subjects. The filter papers were used to evaluate the amount of brilliant sulfoflavine on the unprotected skin fluorometrically. Inhalative exposure was measured with personal air sampler. Plasma concentrations of methyl parathion and its metabolite methyl paraoxon were determined with gas chromatography. Cholinesterase activity in se…
Urinary excretion of heptanones, heptanoles and 2,5-heptanedione after controlled acute exposure of volunteers to n-heptane.
2018
A lack of well-established parameters and assessment values currently impairs biomonitoring of n-heptane exposure. Using controlled inhalation experiments, we collected information on urinary n-heptane metabolite concentrations and the time course of metabolite excretion. Relationships between external and internal exposure were analysed to investigate the suitability of selected metabolites to reflect n-heptane uptake. Twenty healthy, non-smoking males (aged 19-38 years, median 25.5) were exposed for 3 h to 167, 333 and 500 ppm n-heptane, each. Spot urine samples of the volunteers, collected before exposure and during the following 24 h, were analysed for heptane-2-one, 3-one, 4-one, 2,5-d…
Interest of genotyping and phenotyping of drug-metabolizing enzymes for the interpretation of biological monitoring of exposure to styrene
2002
In the field of occupational and/or environmental toxicology, the measurement of specific metabolites in urine may serve to assess exposure to the parent compounds (biological monitoring of exposure). Styrene is one of the chemicals for which biological monitoring programs have been validated and implemented in environmental and occupational medicine. However, inter-individual differences in the urinary excretion exist both for the main end-products (mandelic acid and phenylglyoxylic acid) and for its specific mercapturic acids (phenylhydroxyethylmercapturic acids, PHEMA). This limits to a certain extent the use of these metabolites for an accurate assessment of styrene exposure. In a group…