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131.
Time-weighted average concentrations of selected volatile compounds were measured in chosen residences in a Tri-City area of Poland by means of passive sampling. The results were compared to those obtained by dynamic technique – sorption tubes filled with Tenax TA sorbent. Results obtained by employing the two techniques were similar. Total volatile organic compound (TVOC) parameters were also determined. An attempt was also made to evaluate the influence of outdoor air pollutants on indoor air quality.  相似文献   
132.
In this study, selective methods were developed for isolation, purification, separation and determination of 4-nonylphenol (4NP) in biological samples. Several methods such as high-performance liquid chromatography (HPLC) with fluorescence and diode array detection and gas chromatography coupled to mass spectromotry (GC-MS) are described for the simultaneous determination of 4NP. The nonylphenols in the plasma of fish were extracted through solid phase process by using octadecyl, polymeric and octadecyl endcapping sorbents. The average recoveries in plasma samples spiked with 4NP of levels 1?µg?mL?1 were between 80–95% using added surrogate standards. The aim of this study was to determine whether trace amounts of 4NP in fish plasma samples could be detected by solid phase extraction and chromatographic methods (HPLC, GC-MS). This technique of monitoring the levels of endocrine-disruptors in plasma samples is consistent, reliable as well as inexpensive.  相似文献   
133.
There is a dearth of data on the consumer product concentrations of iron, lead, and nickel for accurate comparison to be made. The levels of these elements were determined in 85 samples of six different classes of personal care products commonly used in Nigeria using atomic absorption spectrophotometry. The results of the analysis showed that the range of the mean concentrations of Fe was 0.485–1.108 ppm, Pb ND–0.163 ppm, and Ni ND-0.160 ppm. The analytical data have demonstrated that the selected consumer products are possible sources of iron, lead, and nickel exposure. Users can be exposed to these metals directly through dermal contact or inhalation. The regulations relating to cosmetic products give no limit values for heavy metals in cosmetic products, hence, it was difficult to establish if the values obtained in this study are safe or not. Prolonged use of soaps, creams, and detergent containing these elements may pose threat to human health and the environment. This could be responsible for various skin diseases such as allergic skin, follicular and pigmentary disorders, which are common among the users (exposed groups) of these products in Nigeria. A body of evidence has presented a rare example of systemic allergic dermatitis caused by topical application of a mercury-containing cosmetic to the upper lip of a 32-year-old Turkish patient.  相似文献   
134.
Excessive intake of nickel (Ni) is known to produce adverse health effects in humans, including carcinogenicity and allergenicity. The main route of exposure for humans is diet, including fish. There is, however, little information concerning Ni content in freshwater fish in Poland. The aim of the study was to determine the concentrations of Ni in meat tissues of three fish species from north eastern Poland and assess toxic potential to healthy and susceptible sub-groups of individuals. The settings for the study lakes span a range of anthropogenic influence from protected areas to a basin with a town and several villages and another one influenced by a pesticide tomb leakage. Fish were netted and kept frozen until analysis. After defrosting, the fish were filleted and minced. The ashed samples were dissolved in nitric acid and analyzed for Ni by flame atomic absorption spectrometry. Roach meat contained 6.6–23 µg kg?1 Ni, bream 9.5–178 µg kg?1, and carp 16.5–139 µg kg?1. These concentrations are low, indicating that the fish were not excessively contaminated with the metal. Consuming a 250 g portion of fish would result in an average nickel intake of 4 µg for roach, <10 µg for bream, and <20 µg for carp. These values represent only 0.4–2% of the maximum level that is likely to pose a risk of adverse effects as established in the USA. Consumption of fish from the study region need not necessarily pose a health threat.  相似文献   
135.
Catecholamines and their metabolites affect children's nervous system. Dopamine is an important neurotransmitter in the brain. In the routine analysis for diagnostics of diseases, the dopamine metabolite homovanillic acid (HVA) is determined. Mercury is a neurotoxic agent and can cause different undesirable effects on the brain. In the present work a putative correlation between HVA, the main metabolite of dopamine, and mercury in urine of healthy and autistic children was studied. The level of HVA was higher in the urine of autistic children (14.5 ± 8.3 mg L?1) compared to generally healthy children (4.4 ± 0.5 mg L?1). The level of mercury in the urine of autistic children was lower (0.36 ± 0.24 µg L?1) than in the urine of healthy children (2.1 ± 1.0 µg L?1) showing that there is no correlation between HVA and mercury.  相似文献   
136.
The present paper examines the degree of environmental contamination in areas covered by the Natura 2000 programme, located in north-western Poland, with selected heavy metals based on their concentration in target organs of roe and red deer. Lead, cadmium, copper, iron, and zinc concentrations were determined by inductively coupled plasma–atomic emission spectrometry. Residues of lead and cadmium were found in most of the analysed samples of roe and red deer organs The concentration of cadmium in the organs of the animals studied was much higher than that of lead. The median for Pb in liver and kidneys was 0.055 and 0.092 μg/g dry weight (d.w.) in roe deer, and 0.067 and 0.081 μg/g d.w. in red deer, respectively. The median for liver and kidney cadmium was 0.770 and 6.139 μg/g d.w. in roe deer, and 0.422 and 6.365 μg/g d.w. in red deer, respectively. Our study has demonstrated that this area is laden with lead and cadmium. This is evidenced by the fact that maximum permissible levels of these elements in the organs of red and roe deer, which were used as bioindicators of environmental contamination, were exceeded.  相似文献   
137.
Germanium is considered to be a non-essential element; however, little is still known about its significance for living organisms. It exerts prophylactic and therapeutic effects in the treatment of serious diseases such as cancer, HIV infection, and others. Germanium does not exhibit acute toxicity, but, as it tends to accumulate in various organs and tissues, undesirable and even dangerous side effects have been reported after prolonged and/or high dosage application. In general, inorganic compounds of germanium are more toxic than its organic compounds. Further studies should be performed to elucidate the exact molecular mechanism of germanium action, to determine the safe and effective dose of germanium via curative/mineral waters, and to understand the applications and benefits of using germanium-enriched waters in balneotherapy. The geochemistry of curative (cold CO2-rich, thermal) waters from spas in the Sudetes (Poland) was clarified in terms of components and mineral phases which might govern germanium. Germanium and silicon in thermal (above 20 °C) waters presumably result from the solubility of silicates in crystalline (granites, gneisses) aquifer rocks and might be controlled by neo-formed quartz. The cold CO2-rich waters revealed a significant diversity of aqueous chemistry and relationships of germanium with iron, silicon, or arsenic. Locally, both in sedimentary (sandstones) and metamorphic (gneisses) aquifer rocks, primary (silicates) and/or secondary (oxides) iron-containing minerals likely release germanium into solution. In the CO2-rich waters of the western part of the K?odzko Region, germanium distinctly correlates with arsenic. It is hypothesized that both elements are co-sourced from crystalline basement and/or migration of substances of post-magmatic origin along deep-seated dislocations related to the seismically active Po?í?í-Hronov fault zone. This area was proposed as the most prospective one for finding waters rich in germanium in the Sudetes.  相似文献   
138.
This paper presents the results of research investigating the impact of flooding on the temporal aspect of transport accessibility at national, regional and local levels in the Mazovia Province – an administrative region in Poland. For the purposes of this study the authors measured the theoretical journey times by private transport between settlement units for two variants: journeys made under normal circumstances, that is, without a flood; and journeys made during a flood event, which would necessitate diversions to avoid flooded road sections. This allowed the theoretical journey time differences to be calculated. It was assumed that vehicles move at the highest permissible speed along routes allowing the shortest travel times. The methods of accessibility assessment employed in this paper are based on distance measurements and use isochrones and a cumulative approach. Analysis carried out by the authors has shown that for interregional, intraregional and local journeys, the flooding of a part of the Mazovia region results in changes in travel times, but their absolute and relative magnitudes vary widely. It was found that in the case of national scale journeys the majority of relative journey time increases were no greater than three times the normal duration, while on a local scale they do not exceed 75%. For areas with a high risk of flooding there should be obligatory analyses of changes in transport accessibility; this would facilitate effective flood risk management. Appropriate traffic management in crisis situations would facilitate emergency and rescue services and help inhabitants and any other persons in flooded areas.  相似文献   
139.
Retractable type fall arresters are part of the equipment used for protecting people against falls from a height. They are an intermediate part between full body harness worn by a man and the structural anchor at the worksite. The most important task of retractable type fall arresters is to arrest people’s falls and to reduce their harmful consequences. Information received from users as well as laboratories testing protective equipment indicates that the performance of such equipment is incorrect under specific conditions. The paper is concerned with an analysis of the conditions in which retractable type fall arresters demonstrate intermittent performance and with an explanation of that phenomenon. The results of tests investigating anchor devices and the performance of retractable type fall arresters are presented. External and internal factors contributing to intermittent performance have been determined and guidelines for safer use of these devices have been developed.  相似文献   
140.
The study aimed at verifying a hypothesis that supporting a visual signal of regulation deviation with an auditory one could improve the quality of regulation; the operator would have better information on machine operation. A special simulator was applied to follow-up tracking with a manual lever which controlled vertical movements of a cursor on a monitor screen. Simultaneously with visual information on screen, the operator was provided with an auditory deviation signal of pre-determined characteristics. 33 young males underwent the test. It was found that supporting a visual signal with an auditory one resulted in an improvement in the regulation quality by 5-6%, which proved synergy between those signals. The results may be used in designing tele- and servo-mechanisms, especially for remote control machinery, e.g., inspection robots or micromanipulators controlled by operators in a follow-up system.  相似文献   
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