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1.
Polychlorinated biphenyl (PCB) and organochlorine pesticide (OCP) levels in fat tissue of red and fallow deer (Cervus elaphus L. and Dama dama L.) from two inland and an Adriatic area were established. Of 17 analysed PCBs, PCB-28, PCB-138, PCB-153, PCB-180 and PCB-118 were found in all samples, whilst PCB-101 and PCB-170 were found in more than 50% of samples. They ranged between 0.03 and 5.98 ng g(-1) fat weight. Of seven analysed OCPs, HCB, γ-HCH and 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (DDE) were found in all samples, whilst β-HCH was found in more than 50% of samples. They ranged between 0.17 and 22.14 ng g(-1) fat weight. The dominating compounds were DDE, PCB-138, PCB153, PCB-118 and PCB-180. According to the Duncan multistage test, the levels of PCB-138, PCB-153, PCB 170 and PCB-180 were significantly higher in perirenal fat samples of specimens taken from the Adriatic area. DDE was significantly higher in the inland deer samples. Some species differences were determined and were mostly related to higher PCB and β-HCH levels in fallow deer samples and higher DDE levels in red deer samples. No sex difference was established. As for age, significantly higher levels of PCB-118 and PCB-52 were found in fawns.  相似文献   

2.
Accumulation of Cu and Cd by Vallisneria spiralis was studied under laboratory conditions. Plants showed ability to reduce 5 µg ml–1 Cu background concentration to below 0.05 µg ml–1 (m.p.l., WHO 1985) within 48 h. The Cd concentration of 1.0 µg ml–1 was reduced to below m.p.l. (0.005 µg ml–1) in 168 h. Cysteine synthesis was more under Cd stress condition. Both the metals were toxic to the plants at higher concentrations; more in the case of Cd.NBRI Rsearch Publication No. 417 (N.S.).  相似文献   

3.
This study performed on randomly selected seven sample plots in leguminous black locust (Robinia pceudoacacia L.) plantations and five sample plots in umbrella pine (Pinus pinea L.) plantations on coal mine soil/spoils. Soil samples were taken from eight different soil depths (0–1, 1–3, 3–5, 5–10, 10–20, 20–30, 30–40, and 40–50 cm) into the soil profile. On soil samples, bulk density, fine soil fraction (Ø < 2 mm), sand, silt and clay rates, soil acidity (pH), organic carbon (Corg), and total nitrogen (Nt) contents were investigated. Also, some forest floor properties (unit mass, organic matter, and total nitrogen) were determined, and results were compared statistically between umbrella pine and black locust. As a result, 17 years after plantations, total forest floor accumulation determined as 6,107 kg ha???1 under black locust compared to 13,700 kg ha???1 under umbrella pine. The more rapid transformation of leguminous black locust forest floor creates organic carbon that migrates further into the mineral profile, and rapid accumulation of C and N in the soil profile was registered. Slower transformation processes of forest floor under umbrella pine result in lower soil N ratio and greater quantity of forest floor. Higher soil pH under leguminous black locust was determined significantly than umbrella pine. In conclusion, the composition of symbiotic nitrogen fixation of black locust appears to be a possible factor favoring carbon and nitrogen accumulation and, consequently, soil development. Clearly, both tree species have favorable impacts on initial soil formation. The umbrella pine generates the more forest floor layer; in contrast, black locust forest floor incorporates into the soil more rapidly and significantly increases soil nitrogen in upper soil layers.  相似文献   

4.
Residues dynamics of Endosulfan (525.00 g a.i. ha(-1)), Imidacloprid seed treatment (21 g a.i. kg(-1)), Lambdacyhalothrin (75.00 g a.i. ha(-1)) and Spiromesifen (225.00 g a.i. ha(-1)) in nectar and pollen of mustard, Brassica juncea (L.) Czern. grown in Himachal Pradesh (India) were determined through bioassay (using Drosophila melanogaster Meig. as test organism) and GC (Gas chromatographic) and HPLC (High performance liquid chromatographic) methods. In general chromatographic methods were more sensitive for the determination of above given pesticides compared to bioassay method. Average recoveries in nectar samples varied between 82.85 and 88.90% by bioassay and 91.20 and 93.55% by chromatographic techniques. In pollen samples, recoveries varied between 81.44 and 86.44% by bioassay and 88.50 and 91.30% by chromatographic methods. Imidacloprid residues were neither found in nectar nor in pollen samples at the time of sampling i.e. 50% of flowering. The order of average half life of residues was: Lambdacyhalothrin (12.45 h) < Spiromesifen (19.99 h) < Endosulfan (27.49 h) for nectar and Spiromesifen (9.69 h) < Lambdacyhalothrin (12.44 h) < Endosulfan (17.84 h) for pollen samples. It was found that Imidcloprid seed treatment was practically harmless to honey bees, whereas a waiting period of 5 days must be observed on crops sprayed with these chemicals during blooms to avoid any accidental hazards to honey bees.  相似文献   

5.
An isolated root uptake test (IRUT) was used to characterize the bioaccumulation of 14C-naphthol in excised root segments obtained from 6-month-old hydroponically grown plants: two varieties of fescue (Festuca arundinaceae Schreb.) and one variety of clover (Trifolium pratense L.). Naphthol uptake rates were directly related to naphthol concentration in the range 0.01 to 0.2 uM. The incubation time required for equilibrium to be reached between naphthol in root tissue and in solution was between 9 and 12 h. Tests using metabolic inhibitors, KCN, NaN3, and DNP, indicated that naphthol uptake may be the result of both passive and active mechanisms. Q10 values for naphthol uptake ranged from 1.05 to 1.16.  相似文献   

6.
Residues of fubendiamide and its metabolite desiodo flubendiamide were estimated in cabbage and soil using high-performance liquid chromatography with UV–vis detector. The initial deposits of flubendiamide residues on cabbage were found to be 0.16 and 0.31 μg g?1 following two applications of flubendiamide 20 WG at 12.5 (standard dose) and 25 (double dose) g a.i. ha?1 respectively at 10-days interval. The half-life values (t 1/2) of flubendiamide on cabbage ranged from 3.4 to 3.6 days. When flubendiamide applied at both the standard and double dose, no detectable residues were found in cabbage and soil at harvest. Thus, a waiting period of 1.63 days was suggested for the safe consumption of flubendiamide-treated cabbage. These data could provide guidance for the proper and safe use of this pesticide on cabbage crops in India.  相似文献   

7.
Residues of flubendiamide and desiodo flubendiamide were studied following three applications of flubendiamide 480 SC at 7 days interval at 90 and 180 g a.i. ha(-1) in/on brinjal fruits. An average initial deposit of 0.33 and 0.61 mg kg(-1) of flubendiamide was observed respectively after application at single and double dosages. The residues of flubendiamide dissipated quickly at both the dosages, and after 3 days, the extent of dissipation was found to be about 76% and 79% at the single and double dosages, respectively. Brinjal fruit samples analysed at different time intervals did not show the presence of desiodo flubendiamide. The half-life of flubendiamide was observed to be 0.62 and 0.54 days at single and double dosages, respectively. The limit of determination of flubendiamide and desiodo flubendiamide was observed to be 0.05 mg kg(-1). Soil samples analysed after 15 days of the last application did not reveal the presence of flubendiamide and desiodo flubendiamide at their determination limit of 0.05 mg kg(-1). An assessment of the total intake of flubendiamide resulting through the consumption of brinjal fruits and its comparison with acceptable daily intake seems to be quite safe from consumer point of view.  相似文献   

8.
Honeybees (Apis mellifera L.) have great potential for detecting and monitoring environmental pollution, given their wide-ranging foraging behaviour. Previous studies have demonstrated that concentrations of metals in adult honeybees were significantly higher at polluted than at control locations. These studies focused at a limited range of heavy metals and highly contrasting locations, and sampling was rarely repeated over a prolonged period. In our study, the potential of honeybees to detect and monitor metal pollution was further explored by measuring the concentration in adult honeybees of a wide range of trace metals, nine of which were not studied before, at three locations in the Netherlands over a 3-month period. The specific objective of the study was to assess the spatial and temporal variation in concentration in adult honeybees of Al, As, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, Ti, V and Zn. In the period of July-September 2006, replicated samples were taken at 2-week intervals from commercial-type bee hives. The metal concentration in micrograms per gram honeybee was determined by inductive coupled plasma-atomic emission spectrometry. Significant differences in concentration between sampling dates per location were found for Al, Cd, Co, Cr, Cu, Mn Sr, Ti and V, and significant differences in average concentration between locations were found for Co, Sr and V. The results indicate that honeybees can serve to detect temporal and spatial patterns in environmental metal concentrations, even at relatively low levels of pollution.  相似文献   

9.
Thiacloprid, a neonicotinoid insecticide with novel mode of action, is found to be effective against several lepidopteran as well as hemipteran pests. The present studies were carried out to observe the persistence pattern of thiacloprid on brinjal and to suggest suitable waiting period for the safety of consumers. Persistence of thiacloprid in brinjal was studied following three applications of thiacloprid (Alanto 240 SC) at 180 and 360 g a.i. ha?1 at 7 days interval. Residues of thiacloprid in brinjal were estimated by high-performance liquid chromatography and were confirmed by liquid chromatography–mass spectrometry. The average initial deposits of thiacloprid were observed to be 0.48 and 1.05 mg?kg?1 on the brinjal fruit following third application of thiacloprid at recommended and double the recommended dosages, respectively. Half-life periods for thiacloprid were found to be 0.47 and 0.50 days at single and double the application rates, respectively. Residues of thiacloprid declined below its limit of quantification of 0.05 mg?kg?1 after 3 and 5 days, respectively, at recommended and double the recommended application rates. Therefore, the use of thiacloprid does not seem to pose any risk hazard and a waiting period of 1 day is suggested for safe consumption of brinjal fruits.  相似文献   

10.
11.
Field experiments were conducted in open top chamber during rabi seasons of 2009–10 and 2010–11 at the research farm of the Indian Agricultural Research Institute, New Delhi to study the effect of tropospheric ozone (O3) and carbon dioxide (CO2) interaction on yield and nutritional quality of Indian mustard (Brassica juncea (L.) Czern.). Mustard plants were grown from emergence to maturity under different treatments: charcoal-filtered air (CF, 80–85 % less O3 than ambient O3 and ambient CO2), nonfiltered air (NF, 5–10 % less O3 than ambient O3 and ambient CO2 ), nonfiltered air with elevated carbon dioxide (NF?+?CO2, NF air and 550?±?50 ppm CO2), elevated ozone (EO, NF air and 25–35 ppb elevated O3), elevated ozone along with elevated carbon dioxide (EO?+?CO2, NF air, 25–35 ppb O3 and 550?±?50 ppm CO2), and ambient chamber less control (AC, ambient O3 and CO2). Elevated O3 exposure led to reduced photosynthesis and leaf area index resulting in decreased seed yield of mustard. Elevated ozone significantly decreased the oil and micronutrient content in mustard. Thirteen to 17 ppm hour O3 exposure (accumulated over threshold of 40 ppm, AOT 40) reduced the oil content by 18–20 %. Elevated CO2 (500?±?50 ppm) along with EO was able to counter the decline in oil content in the seed, and it increased by 11 to 13 % over EO alone. Elevated CO2, however, decreased protein, calcium, zinc, iron, magnesium, and sulfur content in seed as compared to the nonfiltered control, whereas removal of O3 from air in the charcoal-filtered treatment resulted in a significant increase in the same.  相似文献   

12.
Fronds of Spirodela polyrrhiza were treated with different concentrations of Cd and malathion singly and in combinations. Results showed that Cd toxicity was more than malathion. The chlorophyll content was more severely affected by Cd (EC-50 of >1.0 µg ml–1); however, its toxicity was ameliorated in the presence of malathion (EC-50 of 2.0 µg ml–1). Although biomass and frond numbers were least affected by these toxicants, at initial treatment durations fronds multiplication was more severely affected than biomass with an increase in treatment durations. The importance of these findings have been discussed in relation to metal abatement and biomonitoring.NBRI Publication No. (432) NS.  相似文献   

13.
A comparative study of the physico-chemical properties of soil, leafmetal content and foliar surface traits in Lagerstroemia parviflora(L.) Roxb. plants, growing in an iron-rich mineralized and anon-mineralized area was carried out. Metal accumulation wasmaximum in summer; in the peak growing season, it declined duringthe rainy season but picked up again in winter. In leaves sampled froma mineralized region, epidermal cells were much smaller in size buthigher in number per unit area. Changes in the number and size of glandular papillae were also observed. Characteristic non-glandular,elongate trichomes with acute tip were also recorded in mineralizedpopulations. Scanning electron microscopic examination of the foliarsurface configuration revealed distortions in epicuticular wax structuresand wider cuticular striations with typically parallel arrangement inthese populations.The present study shows that high Fe-accumulation in leaves of L.parviflora during the exponential growth phase as well as changes inthe epicuticular structures may be indicators of metal stress in the populations of the mineralized area.  相似文献   

14.
Quizalofop ethyl, a phenoxy propionate herbicide, is used for postemergence control of annual and perennial grass weeds in broad-leaved crops in India. The experiments were designed to study the dissipation kinetics of quizalofop ethyl on onion for two seasons. A simple, rapid, and sensitive method for estimation of quizalofop ethyl residues in onion and soil was developed and validated. The recoveries of quizalofop ethyl residues from onion and soil at different spiking level range from 84.81 to 92.68 %. The limit of quantification of this method was found to be 0.01 μg g?1. The risk assessment through consumption of the onion in comparison to its acceptable daily intake which is an important parameter for the safety of the consumer was also evaluated. Standardized methodology supported by recovery studies was adopted to estimate residues of quizalofop ethyl on onion and soil. The average initial deposits of quizalofop ethyl on onion were observed to be 0.25 and 0.33 mg kg?1, following single application of the herbicide at 50 g active ingredient (a.i.) ha?1 during 2009 and 2010, respectively. The half-life values (T 1/2) of quizalofop ethyl on onion crop were worked out to be 0.85 and 0.79 days, respectively, during 2009 and 2010. At harvest time, the residues of quizalofop ethyl on onion and soil were found to be below the determination limit of 0.01 mg kg?1 following single application of the herbicide at 50 and 100 g a.i. ha?1 for both the periods.  相似文献   

15.
When quantifying imposex in Nucella lapillus, two indices are used: the Vas Deferens Sequence Index (VDSI) and the Relative Penis Size Index (RPSI). Freezing and thawing increase the length of the penis in both male and female Nucella lapillus. In the population studied, this had no significant effect on the RPSI, but was potentially an important source of additional variance in the estimation of the mean penis length.  相似文献   

16.
The measurement of the Relative Penis Size Index (RPSI) in the dogwhelk Nucella lapillus (L.) depends upon reliable observations of the length of the penis (PL). Following removal of soft tissue from the shell, PL increases with time leading to a progressively greater over-estimation of the RPSI. The error is proportionally greater at low RPSI values. To retain comparability with previous data, it is suggested that dogwhelks should be examined as soon as possible after shell crushing.  相似文献   

17.
This paper reports an investigation of the sublethal toxicity of cypermethrin (20 µg/l) on the levels of respiration and selected ions in tissues of carp (Cyprinus carpio L.). A significant decrease in O 2 consumption and ions was observed in gill, brain, liver and muscle tissues of cypermethrinexposed fish. The decreased rate of O 2 consumption may be due to inhibition of oxidative enzymes during cypermethrin stress.  相似文献   

18.
19.
A supervised open field trial was conducted to evaluate the dissipation pattern and risk assessment of flubendiamide in gherkin fruits following foliar application of Fame 480 SC at 60 and 120 g a.i.?ha?1. Samples of gherkin fruits were drawn at different time intervals and quantified by HPLC-DAD. The maximum initial deposits of flubendiamide on gherkin were found to be 0.79 and 1.52 mg kg?1, respectively, at recommended and double the recommended doses. The dissipation pattern of flubendiamide followed a first-order kinetics with half-lives of 1.87 to 2.16 days at 60 and 120 g a.i.?ha?1, respectively. The limit of quantification of flubendiamide and desiodo flubendiamide was observed to be 0.01 mg kg?1 for gherkin fruit and soil substrates. Theoretical maximum residue contribution (TMRC) for flubendiamide was calculated and found to be well below the maximum permissible intake (MPI) on gherkin fruits. Thus, the application of flubendiamide at the recommended dose on gherkin fruits presents no human health risks and safe to consumers.  相似文献   

20.
In this work, experiments were undertaken in an open field having 10,000 m2 area purified from any noise on 121 survey stations using the central frequencies of seven different octave bands with a single and double artificially formed sources of noise. Meteorological parameters such as temperature, humidity, atmospheric pressure, velocity and direction of wind were also taken into consideration. Additionally, the effect of reflecting waves from any surface was also experimentally examined. To evaluate the data obtained, the statistical program of SPSS 9.05 was utilized. From this research, an equation utilising all the parameters was developed.  相似文献   

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