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Ellagic acid (EA), known as a naturally occurring plant phenol, has shown a significant influence on genotoxicity and mutagenicity induced by benzo(a)pyrene (B(a)P) in experiments with sister chromatid exchange (SCE) and Ames Salmonella typhimurium revertants. The maximum inhibitory effect of EA has been detected at low levels of B(a)P doses administered intraperitoneal to mice. The frequency of SCE per chromosome in bone marrow cells induced by B(a)P has been greatly lowered by EA at lower B(a)P doses than 0.5 mg/kg body weight of animals. The number of Ames typhimurium revertants has been reduced in the highest degree at about 10 μg of B(a)P per plate.
Polycyclic aromatic hydrocarbons (PAHs) are more dangerous xenobiotics, very car­ci­no­genic for animals and humans. They are found in air, water, sediments, and plant and animal tissues. most PAHs in the environment are derived during incomplete combustion of organic substances at temperatures lower than 700o C. total emission of all PAHs is very difficult to estimate but the global emission of benzo[a]pyrene is estimated at about 8600 tons/year. Most PAHs are li­po­philic com­pounds that can be bioaccumulated to high levels. Microbial biodegradation and sun­light de­com­po­sition are the main mechanisms for PAH removal from sediments and water. In the present paper the authors will try to de­ter­mine concentrations of 16 PAHs from the US EPA list in river water and drinking water of the ód area to be compared with bibliographic data ob­tained by other chro­mato­graphic methods.
Heavy metal cadmium (Cd) and polycyclic aromatic hydrocarbons benzo(a)pyrene (B(a)P) and pyrene (P) are ubiquitous and persistent environmental pollutants. Human beings are constantly exposed to mixtures of these substances. Exposure to Cd may cause changes in critical organs kidneys and liver. B(a)P has an adverse effect on haemopoesis, digestive systems and on the liver. According to some data Cd, B(a)P and P may interact in all the metabolism phases of xenobiotics. The objective of our study was to investigate the combined effect of Cd, B(a)P and P on general toxicity of the organism of Wistar rats. Tests were conducted on the basis of the methodical recommendations: 407 and 408 of the OECD Guidelines for the Testing of Chemicals. In the experiment, 176 male Wistar-line rats were employed. Four different dose levels were used: 0.1, 0.5, 1.92, 4.0 mg/kg for Cd; 0.00015, 0.0015, 33.3, 10.0 mg/kg for B(a)P and 0.00075, 0.0075, 90.0, 20.0 mg/kg for P and their 4 combinations. The complex of substances studied induced changes in the biochemical blood, urinalysis, hematological parameters which indicated renal and liver function damage and evoked leukopenia symptoms. Evaluating the complex of the substances by these parameters it was noted that the combined action of substances had three types: antagonistic - 56.9%, additive - 27.4% and unknown origin - 15.7%.
The aim of this study was to investigate the accumulation of cadmium (Cd) in the kidneys and its excretion with urine, and possible effect of benzo(a)pyrene (B(a)P) and pyrene on these processes in rats. The studies were conducted on 60 Wistar male rats by short-term (28 d) and subchronic (90 d) experiments. Cadmium was given at doses 0.1 and 0.5 mg/kg. The samples of urine and kidneys were analysed by atomic absorption spectrophotometry. The obtained data showed that Cd in a dose of 0.5 mg/kg significantly increased its renal and urine content; however, the lower dose (0.1 mg/kg) administered during 28 d did not increase Cd urinary excretion levels. This indicates that Cd has a tendency to accumulate in the organism (in kidneys in particular), and when absorbed, is very slowly eliminated from the organism. In short term experiments both doses of Cd increased its accumulation in the kidneys. B(a)P (dose 0.00015 mg/kg) in 28 d and 90 d studies, and pyrene (dose 0.00075 mg/kg) in 90d studies had no effect on the accumulation of Cd in the kidneys and excretion with urine.
The results of the pilot study of exposure to airborne particles and polycyclic aromatic hydrocarbons (PAHs) close to a busy street in Gliwice in the spring are presented. Traffic density in the investigated street between 9 a.m. and 6 p.m. was 1400 vehicles per hour. It was found that average daily concentration of PM10 (airborne particles with aerodynamic diameter ≤ 10 μm) increases by 40 μg/m3 in the street canyon in relation to locations 100 m from the road, which for inhabitants who live in this street means an increased of risk of respiratory diseases by ten percent. The average concentration of total PAHs near the street was 191.56 ng/m3 (in the spring and without rain) and was over 1.5 times greater than at the point 100 m from the street, which confirms that exhaust gases emission on busy streets elevates the exposure to total PAHs. However, it does not concern benzo(a)pyrene (BaP), whose main emission sources seem to be industrial and municipal emitters. Exposure to BaP concerns not only the persons who live close to the busy streets, but the greater population of the Gliwice inhabitants. The risk of cancer diseases in the studied area associated with inhalation of aerosol particles containing BaP is 10⁻⁴, but persons living in the investigated street have a higher cancer risk of 10⁻³ order.
We developed a real-time PCR assay for measuring relative quantities (RQ) of p53 tumor suppressor mRNA in the whitefish (Coregonus lavaretus, Salmonidae, Teleostei). Real-time PCR primers for the p53 gene were designed from a region that was found to be conserved among salmonid p53 genes. To test for the usefulness of the assay we performed a treatment study, using benzo[a]pyrene (B[a]P) a putative p53-inducer. Two groups of hatchery raised whitefish, with an average body mass of 15 g and total length of 12 cm were either given an intraperitoneal injection (10 mg • kg-1) of B[a]P in corn oil (2 mg B[a]P ml-1 corn oil) or corn oil alone (Control). After treatment (48 h, 7°C), two random fish from each group were anesthetized and the liver, head kidney and brain were collected for mRNA isolation and analysis. In the control fish, relative quantification analysis based on the p53 mRNA levels in liver (RQ=1.00) showed higher basal levels of p53 mRNA in the head kidney (RQ=1.69), and lower in the brain (RQ=0.41). In all three tissues sampled, p53 mRNA was affected by treatment with B[a]P. Liver tissue showed the greatest induction (RQ=1.53) from base levels (RQ=1.00), followed by brain (RQ=1.36), and head kidney (RQ=1.23). These results confirm that p53 mRNA is generally present at lower levels in differentiated tissues (liver and brain) than in those tissues with cell lines (head kidney), and demonstrate that p53 is moderately inducible by B[a]P in the whitefish. The approach presented here has the advantage of providing rapid and accurate measures of p53 induction in various tissues of fish responding to PAH contaminant exposure.
The binding of [14Clbenzo[a]pyrene (B[aJP) to DNA and proteins in total nuclei and subnuclear fractions of cultured rat hepatocytes was compared. The main targets of BlaJP were non-histone high molecular weight proteins of the nuclear matrix and DNA sequences attached to this structure. Following 24 h exposure to B[alP the amounts of adducts in the nuclear matrix DNA and proteins were twice as high as in total nuclei. After withdrawal of the carcinogen containing medium the level of B[a]P-induced adducts gradually decreased but always remained the highest in the nuclear matrix proteins. Removal of adducts from the nuclear matrix DNA was more efficient than from the other DNA fractions, and 72 h after exposure to the carcinogen the level of DNA adducts in this fraction was similar to that in total nuclei.
Przeprowadzono analizą 16 podstawowych wielopierścieniowych węglowo- dorów aromatycznych (WWA) w herbatach owocowych i ziołowych. WWA w badanym materiale występowały na poziomie 48,23 do 1703 µg/kg Najwięcej ВaP stwierdzono w herbacie lipowej (74,19 µg/kg).
Przeprowadzono analizę zawartości 23 wielopierścieniowych węglowodorów aromatycznych w wybranych artykułach przeznaczonych do żywienia niemowląt i małych dzieci. Stwierdzone poziomy WWA, a zwłaszcza benzo(a)pirenu są niewielkie i nie przekraczają maksymalnych dopuszczalnych zawartości BaP obowiązujących w Unii Europejskiej. Mleko w proszku zawiera jednak najwyższy wśród przebadanych produktów udział procentowy WWA kancerogennych.
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Zanieczyszczenie olejow roslinnych benzo[a]pirenem

58%
Oznaczono poziom benzo(a)pirenu w 40 próbkach olejów roślinnych pobranych z rynku. Zbadano wpływ ogrzewania oleju w wysokiej temperaturze na jego zawartość. Na podstawie piśmiennictwa porównano występowanie benzo(a)pirenu w tłuszczach roślinnych w innych krajach w odniesieniu do obowiązujących wymagań w Unii Europejskiej.
Przeprowadzono analizą zawartości 16 wielopierścieniowych węglowodorów aromatycznych (WWA) w mięsnych i drobiowych artykułach spożywczych. W części próbek stwierdzono poziom BaP powyżej 1 µg/kg, tj. maksymalnej zawartości przyjętej przez EU dla żywności wędzonej.
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