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1.
Determination of triazines herbicides (atrazine and simazine) by high performance liquid chromatography (HPLC) in samples of trophic chain were worked out. Determination limits of 0.5 μg g−1 for atrazine, 0.8 μg g−1 for simazine with pesticides recovery of 70–77% in trophic chain samples were obtained. The content of simazine in soils was in range 1.72–57.89 μg g−1, in grass 5–88 μg g−1, in milk 2.32–15.29 μg g−1, in cereals 10.98–387 μg g−1, in eggs 30.14–59.48 μg g−1, for fruits: 2.45–6.19 μg g−1. The content of atrazine in soils was in range 0.69–19.59 μg g−1, in grass 7.85–23.85 μg g−1, in cereals 1.88–43.08 μg g−1. Cadmium, lead and zinc were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) in the same samples as atrazine and simazine. Determination limits for cadmium 5 × 10−3 μg g−1, for lead 1 × 10−2 μg g−1, and for zinc 0.2 × 10−3 μg g−1, were obtained. The content of cadmium in soil was in range 0.13–5.89 μg g−1, in grass 114–627.72 × 10−3 μg g−1, in milk 8.88–61.88 × 10−3 μg g−1, in cereals 0.20–0.31 μg g−1, in eggs 0.11–0.15 μg g−1, in fruits 0.23–0.59 μg g−1. The content of lead in soils was in range 0.57–151.50 μg g−1, in grass 0.16–136.57 μg g−1, in milk 1.16–3.74 μg g−1, in cereals 1.05–5.47 μg g−1, in eggs 5.79–55.87 μg g−1, in fruits 21.00–87.36 μg g−1. Zinc content in soil was in range 9.15–424.5 μg g−1, in grass 35.20–55.87 μg g−1, in milk 20.00–34.38 μg g−1, in cereals 14.94–28.78 μg g−1, in eggs 15.67–32.01 μg g−1, in fruits 14.94–18.88 μg g−1.

Described below extraction and mineralization methods for particular trophic chains allowed to determine of atrazine, simazine, cadmium, lead and zinc with good repeatability and precision. Emphasis was focused on liquid–liquid extraction and solid-phase extraction of atrazine and simazine from analysed materials, as well as, on monitoring the content of herbicides and metals in soil and along trophic chain. Higher concentration of pesticides in samples from west region of Poland in comparison to that of east region is likely related to common applying them in Western Europe in relation to East Europe. The content of metals strongly depends on samples origin (industry area, vicinity of motorways).  相似文献   

2.
植物配置对表层流湿地净化效果的影响研究   总被引:2,自引:0,他引:2  
以郑州市贾鲁河河水为处理对象,研究了不同植物配置表层流湿地的水质净化效果及影响因素。研究表明,单纯挺水植物湿地对TN、TP、NH4+-N和COD的平均去除率分别为28%、58%、49%和26%;采用沉水植物+浮叶植物+挺水植物组合的湿地对TN、TP、NH4+-N和COD的平均去除率分别为37%、64%、63%和32%,在对NH4+-N和TN的处理效果上表现出明显的优势,DO含量变化是导致处理效果差异的主要原因。研究结果表明,在湿地植物配置上,可从氮循环的角度,通过合理搭配湿地植物,强化硝化反硝化作用,以提高对氮素的去除效果。  相似文献   
3.
In the present study, endpoints including in vitro pollen performance (i.e., germination and tube growth) and lethality were used as assessments of nanotoxicity. Pollen was treated with 5-10 nm-sized Pd particles, similar to those released into the environment by catalytic car exhaust converters. Results showed Pd-nanoparticles altered kiwifruit pollen morphology and entered the grains more rapidly and to a greater extent than soluble Pd(II). At particulate Pd concentrations well below those of soluble Pd(II), pollen grains experienced rapid losses in endogenous calcium and pollen plasma membrane damage was induced. This resulted in severe inhibition and subsequent cessation of pollen tube emergence and elongation at particulate Pd concentrations as low as 0.4 mg L−1. Particulate Pd emissions related to automobile traffic have been increasing and are accumulating in the environment. This could seriously jeopardize in vivo pollen function, with impacts at an ecosystem level.  相似文献   
4.
This study was a joint physiological and psychological experiment undertaken to determine changes in physiological and psychological human functions under the combined influence of heat, noise, and physical activity. Seven experimental situations were simulated in a climatic chamber with different configurations of three independent variables: heat (40 °C), noise (98 dB), and physical effort (30% of maximum volume of oxygen uptake—V02 max). Five psychological variables (critical flicker fusion—CFF, hand tremor, reaction time, subjective climate evaluation, and subjective evaluation of the given condition load) and two physiological variables (heart rate and rectal temperature) were monitored. Results indicate that CFF changed (increased) significantly when more than one experimental variable was applied. These changes coincided with significant changes in both subjective climate evaluation and subjective evaluation of a given condition load. There were no significant changes in psychomotor functions (hand tremor and reaction time). None of the observed physiological parameters were above the critical value. The results suggest that CFF can be treated as a psychophysical load indicator.  相似文献   
5.
he analysis in this paper was based on data obtained from 80 male participants, aged 29-65. Critical Flicker Fusion Frequency (CFFF) was measured using the Flicker Test. The Formal Characteristics of Behaviour-Temperament Inventory (FCB-TI) by Strelau and Zawadzki (1993) was used for temperamental characteristics. The results of statistical analysis did not confirm a hypothesis about the correlation between CFFF level and 3 temperamental characteristics. There were no immediate relationships among those variables. Correlation was observed when the CFFF coefficient of variance, instead of average CFFF values, was taken into account, especially in the case of a division into 2 groups of participants, “reckless” and “unsure.” It could be interesting to check in the future a hypothesis about the stability of selected types of reactions.  相似文献   
6.
This study was to determine the main health-related reasons, age and occupation of those who took ear retirement due to total work inability. This was done through an analysis of the data from Poland’s Soci Insurance Institution (ZUS) from 2000 and 2001. An analysis of these data showed an increase in the numb of certificates confirming total inability to work in people over 40 years old. Over 50% of certificates wo, were issued to workers in 2 age-groups: 45–49 and 50–54.

Diseases of the circulatory system, musculoskeletal system and connective tissue as well as mental and behavioural disorders are the main causes of early inability to work. Approximately 70% of people who obtained certificates confirming total inability to work had blue- and blue-and-white-collar jobs.  相似文献   
7.
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).  相似文献   
8.
The skin is the part of the human body most vulnerable to ultraviolet (UV) radiation. The spectrum of the negative effects of UV radiation on the skin ranges from acute erythema to carcinogenesis. Between these extreme conditions, there are other common skin lesions, e.g.,photoageing. The aim of this study was to assess the skin for signs of photoageing in a group of 52 men occupationally exposed to natural UV radiation. There were 2 types of examinations: an examination of skin condition (moisture, elasticity, sebum, porosity, smoothness, discolourations and wrinkles) with a device for diagnosing the skin, and a dermatological examination. The results of both examinations revealed a higher percentage of skin characteristics typical for photoageing in outdoor workers compared to the general population.  相似文献   
9.
The contamination of food and feed by mycotoxins as toxic metabolites of fungi is a risk not only for consumers resulting in various embarrassment regarding health status and well-being, but also for producers, companies and export market on the ground of economic losses and ruined stability of economic trade. As it is given in historical evidence, the contamination of food by mycotoxins is a topic as old as a history of mankind, finding some evidence even in the ancient books and records. Nowadays, the mycotoxins are used in modern biotechnological laboratories and are considered an agent for targeting the specific cells (e.g., defected cells to eliminate them). However, this promising procedure is only the beginning. More concern is focused on mycotoxins as abiotic hazard agents. The dealing with them, systematic monitoring, and development of techniques for their elimination from agricultural commodities are worldwide issues concerning all countries. They can be found alone or in co-occurrence with other mycotoxins. Thus, this review aims to provide widened information regarding mycotoxins contamination in environment with the consequences on health of animals and humans. The inevitability for more data that correctly determine the risk points linked to mycotoxins occurrence and their specific reactions in the environment is demonstrated. This review includes various symptoms in animals and humans that result from mycotoxin exposure. For better understanding of mycotoxin's impact on animals, the sensitivities of various animal species to various mycotoxins are listed. Strategies for elimination and preventing the risks of mycotoxins contamination as well as economical approach are discussed. To complete the topic, some data from past as historical evidences are presented.  相似文献   
10.
This paper focuses on comparative review and analysis of the systems of environmental protection, national environmental strategies and fundamentals of environmental legislation in Australia and the Russian Federation. These countries have many socioeconomic similarities, such as low population densities and richness in natural resources which are largely exported. The main disparity between Australia and Russia is in the types of economy. This paper ‘continues’ the sequence of recent scholarly publications on comparison of various features of environmental policies in the countries from all over the world. Comparative analysis in this research has been based on examination of scholarly publications, legislation, government documents, mass media sources and NGO responses. The analysis has revealed a number of differences including top-down implementation of policies in Russia whereas in Australia, each State (Territory) implements policies with significant independence from the Commonwealth Government. At the same time, similarities between the countries have been identified: for example, in deficits in the budget of local environmental authorities and in the presence of contradictions in legislation at national and regional levels of government. Suggestions resulting from this analysis include further integration of sustainable development strategies at all levels of Australian government to encourage further protection of the environment and, for Russia, creating a separate Ministry of Environmental Protection. These approaches should assist facilitation of sustainable development for both nations. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
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