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1.
Northern Cardinal eggs from six neighborhoods near Washington DC were analyzed for organochlorine pesticides and PCBs. All compounds were detected more frequently and at higher concentrations in more heavily urbanized neighborhoods. DDT (mostly as p,p?-DDE) was detected in all neighborhoods. p,p?-DDT was typically 0.5?16 ng/g (ww) in most suburban neighborhoods but was not detected (<?0.1 ng/g) in more rural areas; however, p,p?-DDT was 127?1130 ng/g in eggs from two suburban Maryland nests and comprised 65.7% of total p,p?-DDT isomers in the most contaminated sample, indicating recent exposure to un-weathered DDT. Total chlordane (sum of 5 compounds) was 2?70 ng/g; concentrations were greatest in older suburban neighborhoods. Total PCB (sum of detected congeners) was <?5?21 ng/g. Congener patterns were similar in all neighborhoods and resembled those typical of weathered mixtures. Results indicate that wildlife remains exposed to low concentrations of legacy contaminants in suburban neighborhoods and that cardinal eggs can be used to monitor localized contamination.  相似文献   

2.
In this study, muscle samples gathered from Largehead hairtail (Trichiurus lepturus Linneaus, 1758) and Savali hairtail [Lepturacanthus savala (Cuvier, 1829)] from the Karachi Fish Harbour, Pakistan were analyzed to determine heavy metal concentrations (iron [Fe], zinc [Zn], copper [Cu], manganese [Mn], lead [Pb] and cadmium [Cd]) between January and December 2016. All samples were analyzed using the AAnalyst 700 Flame Atomic Absorption Spectrophotometer. It was observed that the average measured level of Fe, Zn, Cu, Mn, Pb and Cd in muscle were 77.72?±?47.84 µg/g, 20.34?±?8.49 µg/g, 2.23?±?1.16 µg/g, 0.57?±?0.36 µg/g, 0.20?±?0.16 µg/g and 0.42?±?0.19 µg/g for T. lepturus, respectively. Besides, the average level of the same metal concentrations in muscle for L. savala were 85.11?±?57.64 µg/g, 16.63?±?9.25 µg/g, 2.53?±?1.90 µg/g, 0.47?±?0.27 µg/g, 0.23?±?0.18 µg/g and 0.47?±?0.20 µg/g, respectively. The correlation between size groups and metal accumulation in muscle tissues were investigated for both fish. In terms of public risk assessment, the provisional tolerable weekly intake’s of various heavy metals were compared with the consumption of both fish. As a result of the analysis, Fe, Zn, Cu, Mn, Pb and Cd accumulations in muscle tissues of T. lepturus and L. savala collected from Karachi Fish Harbour Pakistan did not exceed limit values.  相似文献   

3.

Backgrounds

To study the effects of supplementation of a marine omega-3 poly-unsaturated fatty acids (n3-PUFA) formulation (Omega3Q10) in older adults with hypertension and/or hypercholesterolemia.

Methods

A total of 97 people were enrolled to receive 12-week supplementation of either Omega3Q10 (n?=?48) or soybean oil (n?=?49). Total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and hypertension-related symptoms were determined before and after the supplementation.

Results

There were no baseline differences between the two groups. Omega3Q10 supplementation significantly reduced diastolic blood pressure (DBP) (from 81.6?±?5.3 mmHg to 79.3?±?5.2 mmHg, P?<?0.05). Blood concentrations of TC and LDL-C decreased significantly and blood HDL-C level increased significantly after 12 weeks of Omega3Q10 (5.5?±?0.7 vs. 5.3?±?0.5, P?<?0.05; 3.7?±?0.8 vs. 3.3?±?0.6, P?<?0.05; 1.2?±?0.6 vs. 1.3?±?0.5, P?<?0.05, respectively) and soybean oil supplementation (5.7?±?0.8 vs. 5.6?±?0.7, P?<?0.05; 3.6?±?0.7 vs. 3.4?±?0.8, P?<?0.05; 1.0?±?0.8 vs. 1.2?±?0.7, P?<?0.05, respectively) but no group differences were found. A significantly greater proportion of the people in the Omega3Q10 group became free from headache and palpitations & chest tightness symptoms after the 12-week supplementation compared to that of the soybean oil group (95.5% vs. 71.4%, P?<?0.01; 95.8 vs. 75.5%, P?<?0.01, respectively).

Conclusion

12-week supplementation of Fish oil-based PUFA appear to be more effective in improving DBP and hypertension-related symptoms than soybean oil in old adults with hypertension and hypercholesterolemia although both supplementation improved TC, LDL-C and HDL-C concentrations.
  相似文献   

4.
The residues of persistent organochlorinated pollutants (POPs), namely polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) (HCHs, CHLs, HCCPs, DDTs, and dicofol congeners) were investigated in the hair and muscle of road-killed Erinaceus roumanicus and E. concolor in Turkey. Mean residue levels were as follows: in hair, PCBs?=?7.43?±?4.88 ng/g and OCPs?=?9.21?±?1.27 ng/g; in muscle, PCBs?=?30.73?±?2.51 ng/g and OCPs?=?145.04?±?16.59 ng/g. There was no significant difference between species and sex, while there was significant difference between habitats and regions in terms of either total PCB and OCP levels, or POP levels (p?<?0.05). Age was a determinative factor for the bio-accumulation of POPs. The contaminant levels were high in the species, sample areas, and habitats. The data also showed that tissues of hedgehogs are suitable for monitoring and evaluating the bioaccumulation of POP levels in Turkey.  相似文献   

5.
Effects of cadmium (Cd) exposure on metal accumulation and energy metabolism of silver carp (Hypophthalmichthys molitrix) were studied during 14 days. The results showed that Cd accumulated in tissues of silver carp significantly with time and Cd concentration, as the order: liver?>?kidney?>?gill?>?muscle. The levels of muscle glycogen, triglyceride, and plasma triglyceride decreased significantly (p?<?0.05). The levels of muscle protein, plasma glucose and lactate significantly increased during the first 8 days, and then all significantly decreased (p?<?0.05). No significant alternations were observed in muscle cortisol, ATP and plasma protein (p?>?0.05). The results indicate that the tissues’ Cd concentrations and energy metabolism were altered by the presence of waterborne Cd, and silver carp mobilizes the muscle energy stores to cope with the increased energy demands for detoxication and repair mechanism induced by the exposure to waterborne Cd.  相似文献   

6.

Backgrounds

Recent experiments suggest that Citrus bergamia extracts could benefit people with dyslipidemia and obesity but this needs to be further validated.

Methods

A total of 98 people age-matched older adults (65 years) with elevated blood lipids were enrolled to receive 12-week supplementation of a Citrus bergamia extracts-based formulation (CitriCholess)(n?=?48) and placebo (n?=?50).

Results

No group differences were found in baseline bodyweight, body mass index (BMI), blood cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and glucose levels. CitriCholess supplementation resulted in lower levels than placebo in TG (1.83?±?0.92 vs. 1.95?±?1.34 mmol/L, P?=?0.612), TC (5.14?±?0.98 vs. 5.44?±?0.77 mmol/L, P?=?0.097), and LDL-C (3.13?±?0.74 vs. 3.43?±?0.62 mmol/L, P?=?0.032). Compared to placebo, CitriCholess also resulted in greater reductions in body weight (?0.604?±?0.939 vs. 0.06?±?0.74 kg, P?<?0.01), waist circumferences (?0.60?±?1.349 cm vs. -0.16?±?1.503 cm, P?<?0.01) and BMI (?0.207?±?0.357 vs. 0.025?±?0.274, P?<?0.01). Additionally, females had a significantly higher level of HDL-C than males. TC was significantly correlated with LDL-C, and to a less degree, with TG. TG was inversely correlated with HDL-C. Body weight and waist circumference were negatively correlated with HDL-C and positively correlated with glucose.

Conclusion

12-week supplementation of CitriCholess could benefit lipid metabolism and weight management in old adults with dyslipidemia.
  相似文献   

7.
The accumulation, elimination and effect of heavy metals on plasma cortisol levels in Oreochromis sp. were studied in the exposure and recovery phases. In the exposure phase, the mean rate of accumulation in the tissues was in the order gill?>?liver?>?muscle for Pb exposure and muscle?>?liver?>?gill for As exposure. In the recovery phase, the order of elimination in the tissues was gill?>?liver?>?muscle for Pb and liver?>?gill?>?muscle for As. The amount of cortisol secreted by the Oreochromis sp. after Pb or As treatment was lower compared to Oreochromis sp. in the control group during the exposure phase. In the recovery phase, plasma cortisol levels in Oreochromis sp. increased in all Pb treatment groups while it continuously decreased in all As treatment groups. A fish affected by As has obvious difficulty recovering from the stress response. It was concluded that exposure to the tested concentrations of Pb and As over 20 days could be a potent endocrine disruptor, which may lead to adverse impacts on the health of the Oreochromis sp.  相似文献   

8.
Residues of hexachlorohexanes isomers (HCHs) and dichlorodiphenyltrichloroethane and metabolites (DDTs) in the soils and sediments of Dayanghan Wetland in Wuhu, China were investigated. The concentrations of ΣHCH in soils and sediments averaged 1.35 and 3.77 μg/kg with the predominance of β-HCH and δ-HCH, respectively. The concentrations of ΣDDT in soils and sediments averaged of 7.80 and 2.80 μg/kg, respectively, with the dominance of o, p′-DDT. The concentrations of HCHs in the soils and sediments and DDTs in the sediments were categorized as no pollution, but the level of DDTs in the soils was classified as low pollution.  相似文献   

9.
The concentrations of four metals (copper, cadmium, zinc and lead) were quantified in blue crabs (Callinectes sapidus) tissues collected in January, April, June and September at two stations in Mersin Bay, northeastern Mediterranean Sea, using ICP-MS. The metal concentrations in crabs from the two stations differed significantly. The hepatopancreas was the major organ accumulating metals, followed by gill and muscle tissues. Except for lead, the highest concentrations of metals were measured in the hepatopancreas. The hepatopancreas had higher concentrations of all heavy metals (Cu 321.1?±?4.30; Zn 182.2?±?3.40; Cd 48.2?±?2.00) compared to gill (Cu 90.2?±?1.35; Zn 104.3?±?2.30; Cd 22.3?±?3.40) and muscle (Cu 19.1?±?1.10; Zn 55.1?±?3.25; Cd 2.5?±?0.20). Among the metals analyzed, Cu, Zn and Pb were the most abundant in the different tissues while Cd was the least abundant in C. sapidus. Seasonality in the levels of the four metals was determined.The highest concentrations of all metals were observed in the June (Zn 55.1?±?3.25; Cu 19.1?±?1.10; Cd 2.5?±?0.20; Pb 5.1?±?0.18) compared to all other months (Zn 34.1?±?3.23; Cu 11.1?±?1.15; Cd 0.9?±?0.20; Pb 3.1?±?0.21).  相似文献   

10.
The toxicity of chlortetracycline (CTC), oxytetracycline (OTC) and enrofloxacin (ENF) was tested on two green algal species: the international standard Pseudokirchneriella subcapitata and the native Argentine species Ankistrodesmus fusiformis. All three antibiotics inhibited the algal growth. The most sensitive species was P. subcapitata, for which the EC50 for CTC, OTC and ENF were 1.19?±?0.53, 0.92?±?0.30 and 5.18?±?3.80 mg L?1, respectively. The EC50 for A. fusiformis, were 3.23?±?0.53, 7.15?±?2.69 and 10.6?±?1.28 mg L?1, respectively. The genotoxicity of these veterinary antibiotics was also assessed using chromosome aberration (CA) and micronuclei (MN) induction in Allium cepa roots. Three concentrations were tested (0.1, 1 and 10 mg L?1). Only ENF at 1 and 10 mg L?1 showed any significant MN induction. These data revealed that CTC, OTC and ENF could cause toxicity on green algae, whereas ENF could cause genotoxicity on A. cepa plants.  相似文献   

11.
This study analyzed the levels of cadmium (Cd), copper (Cu), and zinc (Zn) by the flame atomic absorption spectrophotometer (FAAS), in the muscle tissues, exoskeletons, and gills from freshwater prawn (Macrobrachium rosenbergii) (n?=?20) harvested from natural habitat in Kerang River, Malaysia on 25th November 2015. Significant increase of the metals level in muscle tissue and gill (r?>?0.70, p?<?0.05) were observed with increase in length except for Cu in gills. No relationship was found between metals level in exoskeleton and length. The concentrations of Cd, Cu and Zn were significantly higher (p?<?0.05) in males (muscle tissues and exoskeleton) except for Cd in exoskeleton. In gills, only Cu was significantly higher (p?<?0.05) in female than male. All samples contained metals below the permissible limit for human consumption (i.e., Cd?<?2.00 mg/kg; Cu?<?30.00 mg/kg; Zn?<?150 mg/kg). Annual metals monitoring in prawn and environmental samples is recommended to evaluate changes of metals bioaccumulation and cycling in the system, which is useful for resources management.  相似文献   

12.

Background

Article 10 of the World Health Organization Framework Convention on Tobacco Control states the need for industry disclosure of tobacco contents and emissions. Currently, the profiles of key tobacco compounds in legal and illegal cigarettes are largely unknown. We aimed to analyze and compare concentrations of nicotine, nitrosamines, and humectants in legal and illegal cigarettes collected from a representative sample of smokers.

Methods

Participants of the International Tobacco Control cohort provided a cigarette pack of the brand they smoked during the 2014 wave. Brands were classified as legal or illegal according to the Mexican legislation. Nicotine, nitrosamines, glycerol, propylene glycol, and pH were quantified in seven randomly selected packs of each brand. All analyses were done blinded to legality status. Average concentrations per brand and global averages for legal and illegal brands were calculated. Comparisons between legal and illegal brands were conducted using t tests.

Results

Participants provided 76 different brands, from which 6.8% were illegal. Legal brands had higher nicotine (15.05?±?1.89 mg/g vs 12.09?±?2.69 mg/g; p?<?0001), glycerol (12.98?±?8.03 vs 2.93?±?1.96 mg/g; p?<?0.001), and N-nitrosanatabine (NAT) (1087.5?±?127.0 vs 738.5?±?338 ng/g; p?=?0.006) concentrations compared to illegal brands. For all other compounds, legal and illegal brands had similar concentrations.

Conclusion

Compared to illegal cigarettes, legal brands seem to have higher concentrations of nicotine, NAT, and glycerol. Efforts must be made to implement and enforce Article 10 of the Framework Convention on Tobacco Control to provide transparent information to consumers, regulators, and policy-makers; and to limit cigarette engineering from the tobacco industry.
  相似文献   

13.
Toxicity values for nickel on marine diatoms and copepods were derived based on bioassay tests. The 96 h IC50 of nickel on diatoms, Odontella mobiliensis and Coscinodiscus centralis were 0.31?±?0.01 and 0.62?±?0.02 mg/L and LC50 values on copepods, Oithona similis and Acartia danae were 2.78?±?0.14 and 2.34?±?0.32 mg/L, respectively. The species mean chronic values of nickel were 0.016, 0.17, 0.57 and 0.42 mg/L for O. mobiliensis, C. centralis, O. similis and A. danae, respectively. A hazardous concentration was derived and evaluated using the species sensitivity distribution (SSD) method. SSD indicated that 13 µg Ni/L is the maximum allowable concentration for protection of 95% plankton species in coastal and marine ecosystem of India. Diatoms are more sensitive to nickel than copepods by almost an order of magnitude. The toxicity values derived in the present study may be useful to calculate ambient water quality criteria/standard for nickel.  相似文献   

14.
The present study evaluates potential toxic effects of bis(2-ethylhexyl) adipate (DEHA) plasticizer to larval (72 h post fertilization) zebrafish (Danio rerio) by analyzing changes in expression levels of stress-related genes (p53, rad51 and xrcc5) and assessing possible DNA damage of DEHA in larvae. The lethal concentration for 50% mortality (LC50) in larval zebrafish exposed for 96 h to 0–200 mg L?1 DEHA was 89.9?±?8.03 mg L?1. A concentration-dependent increase in DNA strand breaks was detected in cells from larvae exposed for 96 h to DEHA. There were some significant differences in induction of stress-related genes in larvae exposed to DEHA relative to control.  相似文献   

15.

Purpose

To compare tachycardia and cardiac strain between 24-hour shifts (24hS) and 14-hour night shifts (14hS) in emergency physicians (EPs), and to investigate key factors influencing tachycardia and cardiac strain.

Methods

We monitored heart rate (HR) with Holter-ECG in a shift-randomized trial comparing a 24hS, a 14hS, and a control day, within a potential for 19 EPs. We also measured 24-h HR the third day (D3) after both shifts. We measured perceived stress by visual analog scale and the number of life-and-death emergencies.

Results

The 17 EPs completing the whole protocol reached maximal HR (180.9?±?6.9 bpm) during both shifts. Minutes of tachycardia?>100 bpm were higher in 24hS (208.3?±?63.8) than in any other days (14hS: 142.3?±?36.9; D3/14hS: 64.8?±?31.4; D3/24hS: 57.6?±?19.1; control day: 39.2?±?11.6 min, p?<?.05). Shifts induced a cardiac strain twice higher than in days not involving patients contact. Each life-and-death emergency enhanced 26 min of tachycardia?≥100 bpm (p?<?.001), 7 min?≥?110 bpm (p?<?.001), 2 min?≥?120 bpm (p?<?.001) and 19 min of cardiac strain?≥30% (p?=?.014). Stress was associated with greater duration of tachycardia?≥100, 110 and 120 bpm, and of cardiac strain?≥30% (p?<?.001).

Conclusion

We demonstrated several incidences of maximal HR during shifts combined with a high cardiac strain. Duration of tachycardia were the highest in 24hS and lasted several hours. Such values are comparable to those of workers exposed to high physical demanding tasks or heat. Therefore, we suggest that EPs limit their exposure to 24hS. We, furthermore, demonstrated benefits of HR monitoring for identifying stressful events. ClinicalTrials.gov identifier: NCT01874704.
  相似文献   

16.
The goal of this study was to assess the rate of urea nitrogen uptake (ρ) by Oocystis borgei and the relationship between environmental factors and ρ. Light intensity, temperature, pH, salinity, and algal concentration, were used to construct an empirical model. The results showed that light intensity, algal concentration, pH and salinity had significant effects on ρ, and the optimal combination of environmental conditions for ρ was a temperature of 25°C, pH of 7.0, light intensity of 81 µmol m?2 s?1, salinity of 15‰, and algal concentration of 4.5?×?108 cell L?1–5.5?×?108 cell L?1. The model equation was ρ?=?2?×?10?5?×?(A0.363B0.783C0.045D?0.503E)?+?0.0017, with a coefficient of determination (R2) of 0.83. No significant difference in variance was observed between the model-predicted values and the measured values (F?=?0.238, p?>?0.05), which demonstrated the high fitting degree of the simulation equation. This study provided valuable insight into the reduction of urea nitrogen levels in aquaculture water by O. borgei.  相似文献   

17.
Estrogenic activities of river water from four representative cross-sections of the Yellow River (Zhengzhou section) and their effects on reproduction and development of fish were assessed. MVLN assay showed estradiol equivalents of river water from Yiluohe, Xinmanghe, Qinhe and Huayuankou cross-sections were 1.09?±?0.11, 0.72?±?0.01, 1.19?±?0.19 and 0.80?±?0.04 ng/L, respectively. Significant vitellogenin (VTG) inductions were observed in adult male Japanese madaka (Oryzias latipes) after 30 days of exposure to river water from Yiluohe and Qinhe cross-sections (p?<?0.05). Hepatic-somatic index was significantly elevated in fish exposed to water from Qinhe cross-section (p?<?0.05). A significant delay in time to hatching was observed in embryos treated by water from Xinmanghe cross-section (p?<?0.05). Significant lower survivals were observed in fish treated by water from Yiluohe and Xinmanghe cross-sections after a full life cycle exposure (p?<?0.05). Exposure of water from Yiluohe and Qinhe cross-sections induced significantly elevated VTG levels in the first sexually mature male fish (p?<?0.05). Both the in vitro and in vivo bioassay demonstrate endocrine disrupting chemicals exist in the Yellow River (Zhengzhou section) and fish in Yiluohe and Qinhe cross-sections can be at a risk of reproductive and developmental impairment.  相似文献   

18.
The effects of water pH on life history parameters of Bosmina tripurae have been studied to determine the most suitable water pH desired for the maximum growth and development of this newly discovered cladoceran species. The study was carried out under the laboratory condition at 20?±?2°C. Five pH ranges 5.0?±?0.2, 6.0?±?0.2, 7.0?±?0.2, 8.0?±?0.2 and 9.0?±?0.2 with six replicates for each pH consisting of one animal in each Petri dish (80?×?15 mm) were used for the study. 20 mL of respective test medium was maintained with Chlorella sp. (2?×?104?±?0.03 cells mL?1) in each Petri dish throughout the experiment. Thirty (30) animals were observed daily to investigate different life history parameters like total life span, age at maturity, number of eggs, neonates and egg batches etc. at different condition. From the study it was found that acidic water (pH 5?±?0.2) is more suitable for the culture of Bosmina tripurae in laboratory condition.  相似文献   

19.
This study investigated the use of Dracontomelon duperreanum leaf litter extract (DDLLE) in inhibiting the growth and photosynthesis of the algae Microcystis aeruginosa. The goal of the study was to evaluate a potential solution for cyanobacterial bloom prevention. M. aeruginosa was exposed to extract concentrations from 0.4 to 2.0 g L?1. Chlorophyll-a (Chl-a) content and photosynthesis levels were assessed using pulse amplitude modulated fluorimetry phytoplankton analyzer. Results suggested that the extract could efficiently suppress M. aeruginosa growth. The content of Chl-a was only 19.0 µg L?1 and achieved 96.0% inhibition rate when exposed to 2.0 g L?1 on day 15. Growth rate in response to different extract concentrations were consistent with changes in the photosynthesis efficiency (alpha), maximal relative electron transport rate and maximal photochemical efficiency of photosystem II (F v /F m ). Furthermore, several kinds of volatile chemicals and their concentrations in DDLLE had been identified by GC–MS, which of them play major role to suppress the growth of M. aeruginosa should be further studied.  相似文献   

20.
Discovering cost effective strategies to reduce cadmium (Cd) uptake is of great concern for consumer food safety in the aquaculture industry. This study investigated the protective effects of calcium (Ca) on Cd uptake in co-cultured silver carp (Hypophthalmichthys molitrix) and triangle sail mussel (Hyriopsis cumingii). The results show that Ca—depending on its applied concentration—caused a significant decrease in the Cd uptake into muscle (by 48?%–72?%), gills (by 51?%–57?%), liver (by 52?%–81?%) and kidney (by 54?%–81?%) of silver carp (p?<?0.001), as well as foot (by 8?%–32?%) and visceral mass (by 40?%–47?%) of triangle sail mussels (p?<?0.05). The results indicate that Ca treatment is an effective means of reducing Cd accumulation in aquaculture. Since Ca is often used to increase the quality of pearls produced by triangle sail mussel, the quality of co-cultured edible fish might improve as a consequence of the potentially reduced Cd uptake.  相似文献   

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