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101.
Irene Zorrilla Rosa Martinez Mark A. Taggart Ngaio Richards 《Conservation biology》2015,29(2):587-592
Exposure to residues of the nonsteroidal anti‐inflammatory drug (NSAID) diclofenac present in livestock carcasses has caused extensive declines in 3 Gyps vulture species across Asia. The carcass of a wild Eurasian Griffon Vulture (Gyps fulvus) was found in 2012 on an Andalucian (Spain) game hunting reserve and examined forensically. The bird had severe visceral gout, a finding consistent with Gyps vultures from Asia that have been poisoned by diclofenac. Liver and kidney samples from this Eurasian Griffon Vulture contained elevated flunixin (an NSAID) levels (median = 2.70 and 6.50 mg/kg, respectively). This is the first reported case of a wild vulture being exposed to and apparently killed by an NSAID outside Asia. It is also the first reported instance of mortality in the wild resulting from environmental exposure to an NSAID other than diclofenac. Caso de Sospecha de Envenenamiento por Flunixin de un Buitre Leonado en España 相似文献
102.
The objectives of the present study were to characterize the changes in the proximate chemical composition, lipid classes, fatty-acid profiles, glycogen and cholesterol contents of the muscle, ovary and hepatopancreas of Nephrops norvegicus (L.), during the reproduction cycle of this species. The gonadosomatic index increased significantly in May and June and during maturation, suggesting that spawning may start in late spring or summer. The hepatosomatic index also increased throughout the ovarian maturation, suggesting that the hepatopancreatic resources are not depleted. Positive correlations between lipid levels in the ovary and the gonadosomatic index (r=0.51, P<0.05) and the hepatopsomatic index (r=0.27, P<0.05) were found. In fact, ovarian lipid levels increased with maturation, but no concomitant decrease occurred in hepatopancreatic lipids. The muscle showed very low lipid levels (mainly polar lipids), presenting a significant increase during May and June (P<0.05). Higher proportions of neutral lipids, mainly triacylglycerols, were observed in the ovary and the hepatopancreas. Since both ovarian and hepatopancreatic cholesterol increased with maturation, the mobilization of hepatopancreatic cholesterol stores to build up ovarian cholesterol was not clear. On the other hand, protein and glycogen contents in the muscle, ovary and hepatopancreas did not vary as a function of ovary maturity stage. Among the various tissues analysed, the glycogen was mainly stored in the hepatopancreas and to a lesser extent in the muscle. In both ovary and hepatopancreas the major fatty acids were 16:0, 18:1(n-7), 18:1(n-9), 20:5(n-3) and 22:6(n-3), and significant increases (P<0.05) in the levels of monounsaturated and polyunsaturated fatty acids were observed in the ovary during sexual maturation, which indicates these compounds are the major sources of energy during embryonic and early larval development. It was evident that reproduction has profound effects upon the biochemistry of this species, because there are large associated energy costs, owing to the increase in biosynthetic work, which will support the lecithotrophic strategy of the embryos and first larval stages. 相似文献
103.
Goal and Scope
In soil samples taken from several locations throughout Bavaria, the detection of p,p′-DDT by GC/MS was impeded by a superimposed peak. The authenticity of this compound, which has been identified as dichlorocarbazole by mass spectra databases, is confirmed and some characteristics of its occurrence in soils are described.Methods
The authenticity of the unknown compound has been checked by comparing the low resolution mass spectra and chromatographic retention times with those of standard compounds. Some methodical studies concerning extraction and clean-up were also carried out.Results and Conclusion
Mass spectra and retention of the unknown compound are identical with that of the 3,6-dichlorocarbazole standard compound; additionally, a second chlorocarbazole was found with mass spectrum and retention similar to 3-chlorocarbazole. In many topsoils (A-horizons) and subsoils (B-horizons) from 200 locations of different land-uses, the dichlorocarbazole could be detected. In contrast to PAH and other POPs, maximum concentrations occurred in the A- and upper B-horizons of forest soils rather than in the organic layers. Assuming the environmental distribution properties of the chlorocarbazoles to be similar to those of the PAH, this could indicate that the chlorocarbazoles are not deposited from the atmosphere as a result of anthropogenic activities but might be generated by natural processes in situ.Recommendation and Perspective
To our knowledge, the occurrence of chlorocarbazoles in soils of unpolluted sites has not been previously described. Their widespread occurrence in relatively high concentrations and their detection using analytical standard procedures is surprising and requires further examination. 相似文献104.
Radiotracer experiments were performed (February–April, 1982) to study the assimilation and metabolism of the transuranium nuclide americium-241 in the marine teleosts Serranus scriba (Linnaeus, 1758) and Scorpaena notata Rafinesque, 1810, caught off the Monaco coast. Fish fed with 241Am-labelled food showed that assimilation of this radionuclide takes place through the gastrointestinal walls and that the small fraction accumulated is incorporated mainly in the skin, muscle and skeleton. Gut-transfer coefficients were similar in both species and averaged 0.7% (range 0.1 to 1.7%) of the ingested activity. The calculated biological half-lives for loss of the absorbed fraction ranged between 49 and 61 d for Serranus scriba and 12 and 117 d for Scorpaena notata. Results from an intramuscular injection experiment indicated that 241Am was retained mainly in the liver, skin and skeleton; the fraction accumulated by muscle was very low. Liver displayed a relatively short biological half-time for 241Am loss of roughly 24 d. Routes of 241Am excretion from the teleosts appear to be through the kidneys, gills and feces with bile serving as a possible excretion route from the liver. From the limited amount of published information available for comparison, experimental evidence is presented which suggests that 241Am taken up via the food chain is more biologically available to marine fish than is plutonium. 相似文献
105.
The present study evaluates the impact of lofts on the development of the navigational system of pigeons. A series of results
obtained between 2000 and 2004 were analyzed. The H-loft was placed 10 m above the ground, with a ring format and seven windows
all around it as well as three external aviaries that allowed birds to have a wide view of the outdoors and of the sky and
knowledge of the wind dynamics. The L-loft was placed at ground level, with a single window transformed into an external aviary.
The L-loft was protected from the wind by surrounding trees, reducing the ability of the pigeons to access the wind dynamics
and also restricting their access to information regarding the outside area and the sky. In a preliminary analysis, we found
the parameter of “vanishing time” to differ significantly between lofts in two of the five age classes. A thorough analysis
of this parameter throughout the ontogenetic development of the birds demonstrated a pronounced improvement in the information-processing
system with age, with adults vanishing quicker than younger birds, although an impairment of development occurred during the
third month of age, perhaps due to a reorganization of the system. This result was obtained when the effect of lofts was considered
in the different age classes. Results suggest that loft features are an important factor in the ability of the young pigeons
to exploit navigational cues. 相似文献
106.
PCB and DDT contamination in cultivated and wild sea bass from Ria de Aveiro, Portugal 总被引:1,自引:0,他引:1
Polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) and metabolites were quantified in muscle and liver of sea bass (Dicentrarchus labrax) collected in Ria de Aveiro and in two fish farms. Sea bass from natural environment showed lower levels than fish from farming, which may be partly attributed to the higher lipid content of cultivated fish. PCB congener distribution in tissues of sea bass from the two farms resembled that of diet pellets suggesting that commercial diet is a major source of PCBs. However, fish in the two sites were fed with diet of similar PCB and DDT contamination but showed distinct levels in its tissues not explained by lipid content. 相似文献
107.
The Agency for Toxic Substances and Disease Registry (ATSDR) has a program for chemical mixtures that encompasses research on chemical mixtures toxicity, health risk assessment, and development of innovative computational methods. ATSDR prepared a guidance document that instructs users on how to conduct health risk assessment on chemical mixtures (Guidance Manual for the Assessment of Joint Toxic Action of Chemical Mixtures). ATSDR also developed six interaction profiles for chemical mixtures. Two profiles were developed for persistent environmental chemicals that are often found in contaminated fish and also can be detected in human breast milk. The mixture included chlorinated dibenzo-p-dioxins, hexachlorobenzene, dichlorodiphenyl dichloroethane, methyl mercury, and polychlorinated biphenyls. Two profiles each were developed for mixtures of metals and mixtures of volatile organic chemicals (VOCs) that are frequently found at hazardous waste sites. The two metal profiles dealt with (a) lead, manganese, zinc, and copper; and (b) arsenic, cadmium, chromium, and lead; the two VOCs mixtures dealt with (a) 1,1,1-trichloroethane, 1,1-dichloroethane, trichloroethylene, and tetrachloroethylene; and (b) benzene, ethylbenzene, toluene, and xylenes (BTEX). Weight-of-evidence methodology was used to assess the joint toxic action for most of the mixtures. Physiologically based pharmacokinetic modeling was used for BTEX. In most cases, a target-organ toxicity dose modification of the hazard index approach is recommended for conducting exposure-based assessments of noncancer health hazards. 相似文献
108.
Bioaccumulation and elimination of 14C-lindane in Enchytraeus albidus was studied in artificial OECD soil and a silty loam from an agricultural field in Central West Portugal. Results showed that enchytraeids were able to bioaccumulate the chemical with a kinetic pattern similar to that of earthworms: fast uptake within a few days and a biphasic elimination pattern. A 10 day period to study uptake was sufficient, but a few more days were probably necessary for elimination. Bioaccumulation was influenced by soil type. The authors suggest that higher organic matter (OM) content and also the higher content on sand particles in the OECD soil may have led to a faster elimination: hydrophobic chemicals tend to adsorb to OM being in this way less bioavailable and therefore less bioaccumulated having bioaccumulation factor value around 6 while in natural soil is 10; the sand could act as abrasive particles (helpers) in the elimination process leading to an elimination of 90% of the chemical in two days while in natural soil 67% was eliminated in the same period of time. 相似文献
109.
Pereira FA de Assunção JV Saldiva PH Pereira LA Mirra AP Braga AL 《Journal of the Air & Waste Management Association (1995)》2005,55(1):83-87
To evaluate the possible influence of air pollutants on the incidence of respiratory tract neoplasm we studied 12 S?o Paulo City districts where air pollution is observed. We collected data on pollutants from 1981-1990 and correlated it with the incidence of larynx and lung neoplasms in 1997. Ozone was the pollutant that best correlated with the incidence of neoplasm. The correlation coefficients were 0.7234 (p=0.277) and 0.9929 (p=0.007) for lung and larynx cancer, respectively. There may be a relationship between air pollution and the incidence of respiratory tract neoplasm. This study, however, does not allow us to conclude that there is a causal relationship. 相似文献
110.
G. La Rosa Y. T. R. Proroga D. De Medici F. Capuano M. Iaconelli S. Della Libera E. Suffredini 《Food and environmental virology》2018,10(1):127-131
Shellfish samples (n = 384) from production areas, water samples from the same areas (n = 39) and from nearby sewage discharge points (n = 29) were analyzed for hepatitis E virus (HEV) by real-time and nested RT-PCR. Ten shellfish samples (2.6%) and five seawater samples (12.8%) tested positive for HEV; all characterized strains were G3 and showed high degree of sequence identity. An integrated surveillance in seafood and waters is relevant to reduce the risk of shellfish-associated illnesses. 相似文献