60 research outputs found

    Hydrobiogeochemistry of two catchments in Brazil under forest recovery in an Environmental Services Payment program.

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    Abstract: We investigated the fluvial geochemistry of two catchments at different stages in the forest recovery process which have been a focus of an Environmental Services Payment (ESP) program in Brazil. The Posses (PS) and Salto de Cima (SC) catchments (1200 ha and 1500 ha, respectively) are situated in the municipality of Extrema, Minas Gerais state. Their streams flow into the Jaguari River that supplies part of the water demand of the São Paulo metropolitan area. Samples were collected for chemical analysis and physical-chemical field measures every 2 weeks from January to December 2017. An important pollution point source was discovered in the PS stream related to bovine urine and feces, as well another unidentified source that can be related to a small food processing industry and/or a small fish farm. At the SC stream, on the other hand, there was clear evidence of domestic sewage input. This preliminary study confirmed a limited improvement of the stream water quality in response to recovery of the forest vegetation. Therefore, we recommend that in addition to enhanced monitoring to help distinguish biogeochemical sources and the benefits of land conservation practices, the ESP program should consider controlling point source pollution to accomplish its purpose

    Pre-flight qualification tests of the Mini-EUSO telescope engineering model

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    International audienceMini-EUSO is part of the JEM-EUSO program and operates on board the International Space Station (ISS). It is a UV-telescope with single-photon counting capability looking at nighttime downwards to the Earth through a nadir-facing UV-transparent window. As part of the pre-flight tests, the Mini-EUSO engineering model, a telescope with 1/9 of the original focal surface and a lens of 2.5 cm diameter, has been built and tested. Tests of the Mini-EUSO engineering model have been made in laboratory and in open-sky conditions. Laboratory tests have been performed at the TurLab facility, located at the Physics Department of the University of Turin, equipped with a rotating tank containing different types of materials and light sources. In this way, the configuration for the observation of the Earth from space was emulated, including the Mini-EUSO trigger schemes. In addition to the qualification and calibration tests, the Mini-EUSO engineering model has also been used to evaluate the possibility of using a JEM-EUSO-type detector for applications such as observation of space debris. Furthermore, observations in open-sky conditions allowed the studies of natural light sources such as stars, meteors, planets, and artificial light sources such as airplanes, satellites reflecting the sunlight, and city lights. Most of these targets could be detected also with Mini-EUSO. In this paper, the tests in laboratory and in open-sky conditions are reported, as well as the obtained results. In addition, the contribution that such tests provided to foresee and improve the performance of Mini-EUSO on board the ISS is discussed

    Biomonitoring of complex occupational exposures to carcinogens: The case of sewage workers in Paris

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    <p>Abstract</p> <p>Background</p> <p>Sewage workers provide an essential service in the protection of public and environmental health. However, they are exposed to varied mixtures of chemicals; some are known or suspected to be genotoxics or carcinogens. Thus, trying to relate adverse outcomes to single toxicant is inappropriate. We aim to investigate if sewage workers are at increased carcinogenic risk as evaluated by biomarkers of exposure and early biological effects.</p> <p>Methods/design</p> <p>This cross sectional study will compare exposed sewage workers to non-exposed office workers. Both are voluntaries from Paris municipality, males, aged (20–60) years, non-smokers since at least six months, with no history of chronic or recent illness, and have similar socioeconomic status. After at least 3 days of consecutive work, blood sample and a 24-hour urine will be collected. A caffeine test will be performed, by administering coffee and collecting urines three hours after. Subjects will fill in self-administered questionnaires; one covering the professional and lifestyle habits while the a second one is alimentary. The blood sample will be used to assess DNA adducts in peripheral lymphocytes. The 24-hour urine to assess urinary 8-oxo-7, 8-dihydro-2'-deoxy-Guanosine (8-oxo-dG), and the in vitro genotoxicity tests (comet and micronucleus) using HeLa S3 or HepG2 cells. In parallel, occupational air sampling will be conducted for some Polycyclic Aromatic Hydrocarbons and Volatile Organic Compounds. A weekly sampling chronology at the offices of occupational medicine in Paris city during the regular medical visits will be followed. This protocol has been accepted by the French Est III Ethical Comitee with the number 2007-A00685-48.</p> <p>Discussion</p> <p>Biomarkers of exposure and of early biological effects may help overcome the limitations of environmental exposure assessment in very complex occupational or environmental settings.</p

    Aflatoxin B1 and clinoptilolite in feed for laying hens: Effects on egg quality, mycotoxin residues in livers, and hepatic mixed-function oxygenase activities

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    Ninety-six laying hens were allocated to four groups administered different diets (group 0-0 received a complete diet, group 0-AF received a diet supplemented with 2.5 ppm of aflatoxin B1 [AFB1], group 2-0 received a diet supplemented with 2% clinoptilolite [CPL], and group 2-AF received a diet supplemented with 2% CPL and 2.5 ppm of AFB1) for 4 weeks to evaluate the effect of AFB1 and/or CPL on egg quality and the ability of CPL to interact with the oral administration of AFB1. The possible effects of AFB1 on cytochrome P450-dependent hepatic mixed-function oxygenase (MFO) activities were also evaluated. Mycotoxin reduced yolk weight, while CPL influenced albumen percentage relative to that of eggs laid by chickens in group 0-AF. Eggs laid by chickens in groups 0-AF and 2-AF had stronger shells and weighed less than the eggs of other groups. The eggs of treated groups were lighter in color than those of the control group (P &lt; 0.01), and the tendency to yellowness in eggs was increased by CPL, probably through the affinity of red pigments for adsorbents and a consequent prevalence of yellow tonality. Color parameters might be connected with AFB1's interference with lipid metabolism and pigment deposition. The livers of hens in groups 0-AF and 2-AF showed very low mycotoxin concentrations that were significantly different (P &lt; 0.01). The highest levels observed were those in the livers of the hens receiving the diet supplemented with the mycotoxin alone. AFB1 did not exert any significant effects on the hepatic MFO activities examined

    Effect of Saccharomyces cerevisiae and esterified glucomannan on residues of ochratoxin A in kidney, muscle and blood of layinh hens

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    The in vivo capability of Saccharomyces cerevisiae and of an esterified glucomannan to reduce the oral bioavailability of ochratoxin A added to a basal diet for laying hens was checked over a 12 week period. The residues of ochrtoxin A in kidney, muscle and blood were studied

    Tobacco smoke exposure indicators and urinary mutagenicity.

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    In this study, the correlation of indicators of external (i.e. mean daily intake of condensate, nicotine, tobacco and tobacco proteins, and daily number of cigarettes smoked) and of internal tobacco-smoke exposure (i.e. urinary 1-pyrenol, nicotine and its metabolites and trans,trans-muconic acid) with urinary mutagenicity, detected on YG1024 Salmonella typhimurium strain with S9, were examined in 118 smokers. An increase in urinary mutagenicity was clearly significantly correlated with each external and internal indicators of exposure to tobacco smoke (correlation coefficient (r) ranging between 0.22 and 0.54, P<0.01), with a greater extent in the case of indicators of internal dose. In multiple regression analysis, among the indicators of external exposure, daily tobacco intake was the only variable significantly associated with urinary mutagenicity (t=2.47, P=0.015, with partial contribution to r(2)=5.15%). Instead, when all indicators of exposure (external and internal) were considered in the analysis, the influence of urinary 1-pyrenol on urinary mutagenicity was predominant, followed by those of urinary trans,trans-muconic acid and nicotine plus metabolites (t=4.63, 2.73 and 2.08, P<0.001, P=0.002 and 0.04, with partial contribution to r(2)=17.0, 6.66 and 3.96%, respectively), with no influence at all of external tobacco-smoke exposure indicators. In conclusion, our results show that indicators of internal dose are better correlated with formation of mutagens in urine of smokers. Among these, the best indicator was urinary 1-pyrenol and this result designates the combustion processes of tobacco as the determining step for the formation of urinary mutagens. However, as these biomarkers cannot be analysed the amount of daily tobacco intake represent the best valuable index of external (presumptive) exposure to tobacco-smoke genotoxins

    Effetti di due diverse disponibilità di spazio di allevamento sull'accrescimento e sulle interazioni sociali del suino pesante

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    Sono stati studiati gli effetti di differenti spazi su 40 suini Large White dai 115 ai 160 kg di peso vivo. I risultati mostrano che la disponibilità di 1,3 m2 a capo (superiore quindi a quella raccomandata dall'attuale legislazione (1,0 m2 a capo) esercita effetti favorevoli sul benessere degli animali
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