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PL
Obecność persystentnych związków chloroorganicznych w środowisku naturalnym jest efektem działalności człowieka - zamierzonej (np. produkcja pestycydów, rozpuszczalników, dielektryków, płynów hydraulicznych itp.) jak i niezamierzonej (np.przy produkcji pulpy celulozowej, dezynfekcji chlorem wody do picia, spalaniu odpadów, itp.). Są one szczególnie niebezpieczne ze względu na zjawisko biokumulacji w poszczególnych ogniwach łańcucha pokarmowego oraz działanie toksyczne. W artykule przedstawiono współczesne poglądy dotyczące przemian tych związków w środowisku pod wpływem czynników abiotycznych (fotoliza, hydroliza) oraz biotycznych (biotransformacja przez mikroorganizmy i przemiany w organizmach wyższych).
EN
The presence of persistent organochlorine compounds in the environment is defined as being of anthropogenic origin. They are the result of intentional production (pesticides, solvents, dielectric and hydraulic fluids, flame retardants etc.) as well as they are produced as unintentional by-products from many processes (incineration, pulp and paper production, use and production of chlorinated aromatic chemicals and PVC). Nowadays, they are recognized as one of the major classes of the contaminants in the environment because of their wide distribution and a high capacity to bioaccumulate in organisms - especially in higher levels of the trophic food chain. They have been also claimed to cause adverse effects on organisms and human. In the paper, the main classes of chlorinated hydrocarbons are presented, including pesticides, polychlorinated biphenyls and dioxins. The proposed degradative pathways-abiotic (photolysis, hydrolysis) as well as biotic (biotransformation by microorganisms and higher organisms, including human) are reviewed on the basis of current literature.
PL
Na podstawie przeglądu piśmiennictwa przedstawiono zagadnienie obecności w środowisku trwałych (persystentnych) zanieczyszczeń mogących wywoływać niekorzystny wpływ na układ hormonalny człowieka. Omówiono działanie związków chloroorganicznych wykazujących zdolność do wywoływania odpowiedzi biologicznej zbliżonej do działania żeńskich hormonów płciowych (17β-estradiolu), tzw. ksenoestrogenów oraz mechanizmy prowadzące do nadmiernej proliferacji komórek m.in. gruczołu piersiowego i w konsekwencji zwiększonego prawdopodobieństwa powstania nowotworu złośliwego sutka u kobiet. Opisano badania zależności miedzy stężeniem związków chloroorganicznych w osoczu i tkance tłuszczowej kobiet, a występowaniem nowotworu sutka.
EN
The presence of many chemical pollutants in the environment and their potential impact to human health creates rather justified anxiety. Many of these pollutants feature such unwelcome characteristics as: persistence in different environmental media, ability to bioaccumulate and biomagnify in individual food chains, as well as ability to undergo long-range atmospheric transport. Compounds meeting these criteria include above all a large group of persistent organochlorine compounds. Recently, debate has increased concerning endocrine disrupting activity of these compounds and especially their ability to produce biologic responses comparable to those of endogenous estrogens (e.g. 17β-estradiol). It has been hypothesized that these compounds, among others, may be associated with increased incidence of breast cancer and other estrogen-related cancers in women due to increased proliferation of breast epithelial cells. The organochlorine xenoestrogens may produce this effect following binding to a hormone receptor (with or without metabolic activation) or by affecting the 17ß-estradiol pathways leading to increased formation of more potent estrogenic metabolites. Numerous studies performed since early 1990s have examined the relationship between organochlorines levels in serum or adipose tissue and breast cancer, but the results are not consistent. This may be caused by various criteria of selecting the case and control groups, different compounds analyzed or different statistical approaches. None of these studies included endocrine disruptors' exposure in early and critical stages of development - from conception up to puberty age - the results of which would manifest in far future. Nevertheless the results of measurements, especially in adipose tissue are more reliable for this purpose because they reflect the whole life exposure and may be recognized as one of many environmental risk factors of cancer development.
PL
Przedstawiono wyniki monitoringu pestycydów chloroorganicznych w herbacie i herbatkach owocowych pobranych z obrotu handlowego w Polsce.
EN
Organochlorine pesticides still exist as environmental pollutants in many countries. In this paper, the results of monitoring of organochlorine pesticides in teas taken from the Polish market in 1998 year are presented. The monitoring included analysis of organochlorine insecticides and their metabolites (EDDT, ZHCH, HCB, Heptachlor, Epoxide heptachlor, and Aldrin) in samples of black and green tea, and fruit tea. The mean concentration of the organochlorine compounds in the black tea ranged from 0,0002 to 0,003 mg/kg of product, and in the green and fruit teas from 0,0001 to 0,003 mg/kg of product depending on the pesticide. In no case the violation of the Maximum Residues Limits was observed. The results obtained in this monitoring did not differ from the results reported by the other authors.
PL
Przedstawiono wyniki 5-letnich badań monitorowych pozostałości insektycydów chloroorganicznych w żywności, pochodzącej z 10 województw.
EN
During 1986-1990 4625 samples of food commodities were examined for residues of organo- chlorine (OC) insecticides in 10 voievodships in Poland. This monitoring included analysis of total DDT (DDT+DDE+DDD), α, β and y-HCH, HCB and Metoxychlor (DMDT) in milk and milk products, fruits, vegetables, vegetable oils and baby foods. The median values for DDT in milk and milk products varied from undetectable to 0.23 mg/kg on fat basis, and the draft national tolerance (1,0 mg/kg) was exceeded in 2-5% of samples in 1986 only. In fruits and vegetables the median concentrations of the total DDT usually were below the limit of determination. Generally, during the five years period the downward tendency in DDT complex concentration was observed, but not in case of the total HCH. The residues of OC insecticides in baby foods were generally very low due to establishing of special „low-pesticide" areas for growing raw materials for these products.
PL
Przedstawiono wyniki badań monitorowych pozostałości pestycydów należących do różnych grup chemicznych w środkach spożywczych pochodzenia roślinnego i zwierzęcego. Otrzymane wyniki wskazują na wyraźny wzrost stężeń fungicydów z grupy ditiokarbaminianów w krajowych warzywach.
EN
In this paper, the results of monitoring of pesticide residues in food products are reported for the 3 years period 1995-1997. The monitoring included analysis of organochlorine compounds (DDT and its metabolites - DDD and DDE, HCH isomers α, ß and y, HCB and PCBs), pyrethroids and dithiocarbamates in variety of food products such as: milk and milk products, food for infants and children, fish products, potatoes, domestic fruit and vegetables, citrus and exotic fruits, which were taken from the market. The samples were collected from 15 regions of Poland. Mean values of ΣDDT and ΣHCH in food products of animal origin, including children foods, were much lower comparing with those, reported in previous years. Only few samples | analyzed had violative residues exceeding Maximum Residue Limits (MRLs) for these compounds. In none of food samples of plant origin, organochlorine compounds residues exceed Polish tolerances. The residues of synthetic pyrethroids were detected in none of tested samples of potatoes. Mean concentrations of dithiocarbamate pesticides in fruit and vegetables were higher than observed at the beginning of 1990s. In five samples of leaf and stem vegetables, the detected levels of dithiocarbamates exceed or were equal to MRLs.
PL
Przedstawiono wyniki monitoringu insektycydów chloroorganicznych w owocach cytrusowych znajdujących się na rynku w Polsce. Badano poziomy tych związków zarówno w części jadalnej owocu, jak i w skórce.
EN
The monitoring of organochlorine insecticides (HCB, HCH, and DDT) in citrus fruits taken from the market was carried out in 9 regions in Poland in the years 1996-1997. The concentrations of the insecticides were measured in the edible part and in the peel separately. The total number of 331 samples of oranges, lemons, grapefruits and mandarins were subjected residue analysis. The mean concentrations of the organochlorine compounds in the edible parts amounted 0.0002 mg/kg for HCB, and ranged from 0,0081 to 0.0247 mg/kg for IHCH and from 0,0041 to 0.022 for DDT depending on the product. The highest contrentrations together with the highest violation rate (9.5%) of the Polish Maximum Residue Limit was found in case of DDT. The mean concentrations of the insecticides in the citrus peels were not markedly higher than those in the edible parts. The results obtained in this monitoring did not differ from the results reported by the other authors.
PL
Przedstawiono zasady przeprowadzania badań biegłości oraz statystycznej oceny wyników. Omówiono także korzyści dla laboratorium wynikające z udziału w takich badaniach.
EN
In order to promote in Poland the effective response to the international food regulations and to enhance the ability of laboratories in proving their analytical quality assurance, some general guidelines for proficiency testing have been presented according to the internationally recognised protocol (IUPAC/ISO/AOAC The International Harmonized Protocol for Proficiency Testing). The objectives of proficiency testing and its importance for accreditation for analytical laboratories were also reviewed with the special emphasis given to those dealing with food analysis. The organization of interlaboratory trials and methods for statistical treatment of results were also described, as well as reporting of results and their statistical evaluation. The proficiency testing according to the above described rules are routinely performed by the Department of Environmental Toxicology of the National Institute of Hygiene for organochlorine pesticides and PCB s in food.
PL
W opracowaniu przedstawiono przegląd piśmiennictwa dotyczący metabolizmu i toksyczności bromopochodnych aromatycznych stosowanych jako środki uniepalniające (zmniejszające palność).
EN
Flame retardants are added to plastic materials, textiles, wood, hydraulic liquids etc. for reducing their inflammability. These substances reduce the heat and carbon monoxide formation in case of fire. They are added in high amounts, even up to 30% of product mass (e. g. plastic material). The production of brominated flame retardants has been steadily rising in the last 20 years, e. g. in the 1990s the world production of polybromodiphenyl ethers (PBDE) reached 40000 tons annually. Mainly polybrominated flame retardants are produced, e. g. polybromobiphenyls (PBB), PBDE, hexabromobenzene (HBB). Their toxicity is low or nil, the DL 50 values are over 1 g/kg. However, when administered in low doses over longer time periods they can cause changes leading to porphyria. The information on the toxicity of polybrominated flame retardants for humans is derived mainly from the accident in Michigan, where PBB contamination of fodder for farm animals occurred with consequent contamination of food. In consumers of contaminated food cutaneous changes and neurological and muscular symptoms were noted. Polybrominated flame retardants can be metabolized and undergo biodegradation mainly trough denomination. The data on the toxicity of debromination products point to di-and tribromobenzenes, some of which are highly hepatotoxic. In acute poisoning hepatocellular damage manifest itself as necrotic changes in experimental animals receiving 0.1-0.8 of DL 50 of di-or tribromobenzene. After repeated administration of lower doses the hepatocellular damage assumes the features of porphyrogenic injury. In the environment polybrominated flame retardants can be transformed by various factors (high temperature during fire accidents, incomplete incineration of waste) to polybrominated dibenzodioxins of dibenzofurans whose lethal doses can in extreme cases be 0.001 mg for 1 kg body weight.
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