Dust from Zambian smelters: mineralogy and contaminant bioaccessibility

Metal smelting is often responsible for local contamination of environmental compartments. Dust materials escaping from the smelting facilities not only settle in the soil, but can also have direct effects on populations living close to these operations (by ingestion or inhalation). In this particular study, we investigate dusts from Cu–Co metal smelters in the Zambian Copperbelt, using a combination of mineralogical techniques (XRD, SEM/EDS, and TEM/EDS), in order to understand the solid speciation of the contaminants, as well as their bioaccessibility using in vitro tests in simulated gastric and lung fluids to assess the exposure risk for humans. The leaching of metals was mainly dependent on the contaminant mineralogy. Based on our results, a potential risk can be recognized, particularly from ingestion of the dust, with bioaccessible fractions ranging from 21 to 89 % of the total contaminant concentrations. In contrast, relatively low bioaccessible fractions were observed for simulated lung fluid extracts, with values ranging from 0.01 % (Pb) up to 16.5 % (Co) of total contaminant concentrations. Daily intakes via oral exposure, calculated for an adult (70 kg, ingestion rate 50 mg dust per day), slightly exceeded the tolerable daily intake limits for Co (1.66× for fly ash and 1.19× for slag dust) and occasionally also for Pb (1.49×, fly ash) and As (1.64×, electrostatic precipitator dust). Cobalt has been suggested as the most important pollutant, and the direct pathways of the population’s exposures to dust particles in the industrial parts of the Zambian Copperbelt should be further studied in interdisciplinary investigations.     

Analysis of Conditions and Organization of Work of Notebook Computer Users

Abstract

Aim. The aim of this study was to evaluate working conditions with a notebook computer (notebook) as a potential cause of musculoskeletal disorders. Material and methods. The study had 2 stages. The first one was a questionnaire survey among 300 notebook users. The next stage was an expert analysis of 53 randomly selected workstations. The questionnaire survey included questions about the participants, their working conditions, work organization and also duration of work with a notebook. Results and conclusions. The results of the research showed that most examined operators used a notebook as a basic working tool. The most important irregularities included an unadjustable working surface, unadjustable height of the seat pan and backrest, unadjustable height and distance between the armrests and no additional ergonomic devices (external keyboard, docking station, notebook stand or footstool).     

阿瓜斯阿根廷斯承包区净化处理的新模式： 有助于解决布宜诺斯艾利斯环境问题的工具

布宜诺斯艾利斯市的增长伴随着环境的逐渐恶化,其中包括水流的质量 .随着情况的全面恶化, 1993年政府将饮用水厂进行了为期 30年的私有化,并在布宜诺斯艾利斯市及其 17个郊区社区进行净化处理 .阿瓜斯阿根廷斯 (Aguas Agentinas)的用水操作者是里昂水业集团,为了响应当局的要求,提出并着手进行净化处理的新指导模式,这有助于解决该承包区目前的环境问题 .     

Relationships between volatile organic compounds with an emphasis on terpene compounds and genetic matrix in inoculated and non-inoculated winter wheat cultivars

In the present study, we focus on the analysis of the volatile organic compound (VOC) contents in the grain of a representative set of winter wheat cultivars grown in Central Europe. The cultivars were grown in control conditions or were inoculated with the fungus Fusarium culmorum. In the analysed samples, hydrocarbons, alcohols, aldehydes and ketones, aromatics, terpenes and others were found. Among them, results for terpenes seem particularly important. The discriminant analysis allowed complete separation of the quality groups of wheat based on VOCs. Simultaneously, a genetic matrix was created based on the genetic distance between the wheat cultivars and the Mantel test was used to compare it with the VOC matrix. The analysis revealed relationships between the genetic matrix and the overall VOCs, as well as terpenes. The obtained results indicate a significant relationship between microorganisms that exist in the environment, genetic features of plants and VOCs formed in the grain.     

Monitoring of agriculture soils in the Czech Republic

In the Czech Republic a complex monitoring of agriculture soils has commenced. This paper describes the approach to establishing monitoring plots. Comparing the results of Systematic Soil Survey and those from the first period of agriculture monitoring demonstrates that a representative set of plots was achieved. Soil properties (physical, chemical, biological and agronomical), atmospheric deposition (some parameters being monthly and some only for the summer and winter season) and selected other influences (application of pesticides, irrigation, etc.) are all monitored. Results for atmospheric deposition in the Czech Republic from the first period and Bavaria [Bayerische Landesanstalt für Bodenkultur und Pflanzenbau, 1992) are also compared. Data are evaluated by a statistical package (Statgrafics) and prepared for future transfer into a suitable GIS.     

Soil burdens of persistent organic pollutants - Their levels, fate and risk. Part I. Variation of concentration ranges according to different soil uses and locations

Detailed soil screening data from the Czech Republic as a typical Central European country are presented here. Determination of a wide selection of organic and inorganic pollutants as well as an assessment of specific soil parameters allowed us to study the soil contamination in relation to the land use and soil properties. While HCHs and HCB were found at highest levels in arable soils, the higher concentrations of PCDDs/Fs, PCBs, PAHs and DDTs were observed in high altitude forest soils. Concentrations of these compounds strongly correlated with the soil organic carbon content. Several possible reasons have been suggested for the observed higher concentrations in mountain forest soils but the impact of each of these influencing factors remains to be identified. An inventory of the soil contamination is needed as a first step in our effort to estimate an extent to which the secondary sources contribute to the enhanced atmospheric levels of POPs.     

Work ability in ageing workers suffering from chronic diseases.

The aim of this study was to investigate the work ability in ageing workers suffering from osteoarthritis (OA), coronary heart disease (CHD) or hypertension (H). One hundred and sixty-six OA and 355 CHD/H outpatients were evaluated. The Work Ability Index (WAI) served for work ability assessment. Patients' results were compared with the results of a control group of 225 healthy young workers. Statistical analysis was performed with ANOVA tests. WAI in female and male CHD/H patients was higher than in OA patients (p < .01), better work ability was related to better education (p < .01), white-collar work (p < .01) and better recreation (p < .01); subjective work ability was determined mostly by the objective health status. The promotion of work ability among workers suffering from advanced age-related diseases should be closely related to the promotion of health. It is indicative to improve occupational education and skills, already at an early stage of a disease.     

Activity of the principal digestive enzymes in the detritivorous apodous holothuroid Leptosynapta galliennei and two other shallow-water holothuroids

Digestive ability by means of hydrolytic enzyme activities was studied in Leptosynapta galliennei (Herapath, 1865) and two other shallow-water deposit-feeding holothuroids: L. inhaerens (O. F. Müller, 1776) and Holothuria (Panningothuria) forskali (Delle Chiaje, 1828). The holothuroids were collected throughout the year at Roscoff (Britanny, France) from 1980 to 1985, except for L. inhaerens, which was collected in Galway Bay (Ireland) in June/July 1980. Using 25 substrates, the activity of 21 enzymes were recorded to detect hydrolysis of esters (5 substrates), glycosidic bonds (12 substrates) and peptide bonds (8 substrates). The activities of the homogenates of various parts of the gut as well as the digestive juice were measured. Esters and relatively long-chained fatty acids (up to C₁₄) were hydrolysed. Significant hydrolysis of naturally occurring disaccharides and starch (reserve carbohydrate) occurred. The holothuroids were also able to digest hydrolysis products of cellulose and chitin. This may also indicate a capacity to digest the products of complex compounds such as glycolipids or glyco-proteins. Exopeptidases capable of hydrolyzing peptides were present, but endopeptidases able to digest proteolytic chains were not. Most enzymatic activities occurred in all parts of the gut, but some were strictly localized, usually to the anterior intestine. Extracellular digestion of fatty acids, starch and saccharose occurred only in this latter digestive segment. Disaccharidases and peptidases are linked to the plasma membrane of enterocytes. Enzymatic activities associated with lysosomes occur throughout the gut. The diet of shallow-water holothuroids is omnivorous, with a marked preference for food of vegetable origin. Annelids and holothuroids possess a similar capacity to hydrolyse most types of bonds, including peptide bonds. The chemical nature of detritus and its relationship to the nutritional requirements of detritivores must be defined, and gut-retention time ascertained, to discover if different digestive strategies are developed by different detritivores to exploit the same food source in a given environment.     

Carpal tunnel syndrome in occupational medicine practice.

Work-related overload syndromes are chiefly associated with the upper limbs, where carpal tunnel syndrome (CTS) plays a leading role. This article analyses methods of diagnosing CTS, with special emphasis on those that can be used by physicians in early diagnosis of CTS in workers doing monotonous work. It also discusses occupational (e.g., assembly work, typing, playing instruments, packaging and work associated with the use of a hammer or pruning scissors) and extra-occupational factors (e.g., post-traumatic deformation of bone elements of the carpal tunnel, degenerative and inflammatory changes in tendon sheaths, connective tissue hypertrophy or formation of crystal deposits) leading to CTS; diagnostic methods (subjective symptoms, physical examination and manual provocative tests, vibration perception threshold, electrophysiological examination and imaging methods); and therapeutic and preventive management tools accessible in occupational medicine practice.