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1.
Perylene, a 5-ring polycyclic aromatic hydrocarbon is common in estuarine sediments and its toxicity in the benthic and planktonic compartments is not yet clarified. The objectives of this work were: (1) to follow the toxicity of high concentrations of perylene (110 mg l−1) on benthic bacteria and macrofauna (amphipod Corophium multisetosum); (2) to determine the effects of a low load of perylene (2 μg l−1) on the metabolism of suspended bacteriobenthos after 9-day exposure, mimicking the effects of tidal erosion; (3) to contrast the effects of this low perylene load on the particle-free bacterioplankton and on the suspended and particle-adhered bacteriobenthos. No impact was detected in bacterial abundance exposed to 110 mg perylene l−1 for 9 days. This concentration of perylene evoked no acute effects in C. multisetosum but, chronic toxicity assays revealed statistically significant negative effects on survival, growth and number of pregnant females. The bacterioplankton and the suspended bacteriobenthos, exposed to 2 μg perylene l−1 during 2 weeks, responded with altered profiles of activity when compared to the control suspension. These values ranged, respectively, for bacterial biomass production from 134 to 210 and from 24 to 184 μg C l−1 h−1, for aminopeptidase from 1824 to 11,127 and from 1464 to 15,488 nmol l−1 h−1, and for β-glucosidase from 87 to 400 and from 57 to 1278 nmol l−1 h−1. The rate of oxygen consumption in the perylene-exposed suspension (0.04–2.85 mmol O2 kg−1 dw sed h−1) exhibited a clearly distinct profile in relation to the control (0.57–1.60 mmol O2 kg−1 dw sed h−1). The overall reactivity of the bacteriobenthos to perylene was interpreted as the result of toxic pressure followed by evolution of a diverse bacterial community.  相似文献   

2.
Serum lead, cadmium and zinc levels from 31 newborns with neural tube defects (NTD), and 54 healthy controls living in a polluted area in Mexico were estimated using atomic absorption spectrophotometry (AAS). NTD family history was found to be of greater importance in the case group (OR 6.95, 95% CI 1.51-36.3, p=0.002). In 25% of the children, serum lead concentrations were above the admissible maximum level (AML) of 10 microg/dL within 24 h of extra-uterine life. Cadmium concentrations were below the AML. Zinc deficiency was found in nine (29%) of the cases and four (9.3%) of the controls (p=0.04). The logistic regression multivariate analysis showed no correlation between NTD and high levels of any of these metals; however, a positive correlation was found to zinc deficiency (OR 5.0, 95% CI 1.07-23.00, p=0.04). These results focus attention to the surrounding nutritional and maternal health factors of major importance in disease etiology.  相似文献   

3.
Humans can be exposed to multiple chemicals, but current risk assessment is usually carried out on one chemical at a time. Mycotoxins are commonly found in a variety of foods including those intended to consumption by children namely breakfast cereals. The present study aims to perform, the risk assessment of single and multiple mycotoxins present in breakfast cereals consumed by children (1–3 years old) from Lisbon region, Portugal. Daily exposure of children to ochratoxin A, fumonisins and trichothecenes showed no health risks to the children population considering individual mycotoxins, while exposure to aflatoxin B1 (AFB1) suggested a potential health concern for the high percentiles of intake (P90, P95 and P99). The combined exposure to fumonisins and trichothecenes are not expected to be of health concern. The combined margin of exposure (MoET) for the aflatoxins group could constitute a potential health concern and AFB1 was the main contributor for MoET. Legal limits and control strategies regarding the presence of multiple mycotoxins in foodstuffs is an urgent need. To the best of our knowledge, this is the first time a cumulative risk assessment was performed on multiple mycotoxins present in breakfast cereals consumed by children.  相似文献   

4.
This special issue examines bioaccumulation and risks of methylmercury in food webs, fish and wildlife in the Laurentian Great Lakes region of North America, and explores mercury policy in the region and elsewhere in the United States and Canada. A total of 35 papers emanated from a bi-national synthesis of multi-media data from monitoring programs and research investigations on mercury in aquatic and terrestrial biota, a 3-year effort involving more than 170 scientists and decision-makers from 55 different universities, non-governmental organizations, and governmental agencies. Over 290,000 fish mercury data points were compiled from monitoring programs and research investigations. The findings from this scientific synthesis indicate that (1) mercury remains a pollutant of major concern in the Great Lakes region, (2) that the scope and intensity of the problem is greater than previously recognized and (3) that after decades of declining mercury levels in fish and wildlife concentrations are now increasing in some species and areas. While the reasons behind these shifting trends require further study, they also underscore the need to identify information gaps and expand monitoring efforts to better track progress. This will be particularly important as new pollution prevention measures are implemented, as global sources increase, and as the region faces changing environmental conditions.  相似文献   

5.
This study presents concentrations of mercury in tissues (feather, kidney, liver, and muscle) of three kingfisher species from Shadegan Marshes located in the Khuzestan province in the lowlands of southwestern Iran at the head of the Persian Gulf. The order of mercury concentrations in tissues of all the kingfishers such as pied kingfisher (Ceryle rudis), common kingfisher (Alcedo atthis) and white-breasted kingfisher (Halcyon smyrnensis) was as follows: feather > kidney > liver > muscle. No significant difference was detected in mercury tissue levels between species of birds. Liver mercury concentration was positively correlated with kidney mercury levels in all of the three species of kingfishers. Although, the average levels of mercury we observed in these birds were below levels known to be associated with adverse behavioral or reproductive effects, mercury levels in some individual birds exceeded adverse effect level.  相似文献   

6.
The present study aimed to characterize five commercial honeys available in the Portuguese market in respect to their floral origins, physicochemical parameters and microbial safety and commercial quality assessment. Pollen profile, colour, moisture content, ash, acidity, electrical conductivity, pH, reducing sugars, apparent sucrose and HMF were the parameters analysed in each honey sample. Aerobic mesophiles, moulds and yeasts, fecal coliforms and sulphite-reducing clostridia were the microbial contaminants of interest studied. The antimicrobial effect against four fermentative yeasts was determined.  相似文献   

7.
In this study, the serum levels, including thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone(TSH)among the subjects from the exposed group (n = 48) and the control group (n = 45) were detected by immuno radiometric assay (IRMA). The expression levels of TRα1, TRβ1, TSHR mRNA in placentas and umbilical cords were detected by fluorescent quantitative real-time PCR (FQ-PCR). The correlations between the thyroid hormone levels in maternal serum and umbilical serum, and between the expression levels of its receptors mRNA in placentas and umbilical cords were determined. We found that the FT4 levels of both maternal serum and umbilical cord serum in the exposed group were lower than those in the control (P < 0.05). However, the increased TSH levels in the exposed group had statistically significance compared to those in the control group (P < 0.05). The TRα1 and TRβ1 mRNA levels both in placentas and umbilical cords in the exposed group were lower than those in the control group (P < 0.05 and 0.01). However, the TSHR mRNA levels in the exposed group were significantly different compared to those in the control group (P < 0.01). The serum FT4 and TSH levels of parturient women were positively correlated with those of the newborns in both groups (P < 0.05 and 0.01). The mRNA levels of TRα1, TRβ1 and TSHR in the placentas were positively correlated with those in umbilical cords in both groups (P < 0.01). The findings suggest that some environmental pollutants existing in the electronic waste (e-waste) dismantling region may affect the health of local parturient women and newborns, representing changes both in serum levels of thyroid hormones and in mRNA expression of its receptors.  相似文献   

8.
Three commonly consumed and commercially valuable fish species (sardine, chub and horse mackerel) were collected from the Northeast and Eastern Central Atlantic Ocean in Portuguese waters during one year. Mercury, cadmium, lead and arsenic amounts were determined in muscles using graphite furnace and cold vapour atomic absorption spectrometry. Maximum mean levels of mercury (0.1715 ± 0.0857 mg/kg, ww) and arsenic (1.139 ± 0.350 mg/kg, ww) were detected in horse mackerel. The higher mean amounts of cadmium (0.0084 ± 0.0036 mg/kg, ww) and lead (0.0379 ± 0.0303 mg/kg, ww) were determined in chub mackerel and in sardine, respectively. Intra- and inter-specific variability of metals bioaccumulation was statistically assessed and species and length revealed to be the major influencing biometric factors, in particular for mercury and arsenic. Muscles present metal concentrations below the tolerable limits considered by European Commission Regulation and Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). However, estimation of non-carcinogenic and carcinogenic health risks by the target hazard quotient and target carcinogenic risk, established by the US Environmental Protection Agency, suggests that these species must be eaten in moderation due to possible hazard and carcinogenic risks derived from arsenic (in all analyzed species) and mercury ingestion (in horse and chub mackerel species).  相似文献   

9.
《中国医药科学》2020,(1):137-140
目的分析茂名市新生儿维生素D水平现状及其影响因素。方法选取2016年3月~2019年3月茂名市地区新生儿1000例作为研究对象。检测所有新生儿血清25-(OH) D水平,同时收集新生儿及产妇一般资料。分析所有新生儿维生素D缺乏状况。以血清25-(OH) D <20ng/mL(50nmol/L)记为维生素D缺乏,Logistic回归分析患儿维生素D缺乏的影响因素。结果 1000例新生儿血清25-(OH) D平均值为(19.36±7.89)ng/mL,其中,86例新生儿维生素D严重缺乏,平均值为(9.29±0.39)ng/mL,543例新生儿维生素D轻度缺乏,平均值为(15.08±2.94)ng/mL,260例新生儿维生素D不足,平均值为(24.97±2.78)ng/mL,111例新生儿维生素D充足,平均值为(34.99±3.79)ng/mL,新生儿维生素D缺乏患病率为62.90%。二元Logistic回归结果显示,居住地(OR=1.582,95%CI=1.211~2.066,P=0.001)、教育程度(OR=0.628,95%CI=0.486~0.811,P=0.000)、日照时长(OR=1.539,95%CI=1.1816~2.006,P=0.001)、补充维生素D和钙剂情况(OR=1.571,95%CI=1.211~2.066,P=0.001)、分娩季节(OR=1.187,95%CI=1.046~1.347,P=0.008)是新生儿维生素D缺乏的影响因素。结论茂名市地区新生儿维生素D缺乏患病率较高,居住农村、学历低、日照时长短、未常规补充维生素D和钙剂以及冬春季节分娩是新生儿维生素D缺乏的影响因素。  相似文献   

10.
Mining activities may affect the health of miners and communities living near mining sites, and these health effects may persist even when the mine is abandoned. During mining processes various toxic wastes are produced and released into the surrounding environment, resulting in contamination of air, drinking water, rivers, plants, and soils. In a geochemical sampling campaign undertaken in the Panasqueira Mine area of central Portugal, an anomalous distribution of several metals and arsenic (As) was identified in various environmental media. Several potentially harmful elements, including As, cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se), were quantified in blood, urine, hair, and nails (toe and finger) from a group of individuals living near the Panasqueira Mine who were environmentally and occupationally exposed. A group with similar demographic characteristics without known exposure to mining activities was also compared. Genotoxicity was evaluated by means of T-cell receptor (TCR) mutation assay, and percentages of different lymphocyte subsets were selected as immunotoxicity biomarkers. Inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis showed elevated levels of As, Cd, Cr, Mn, and Pb in all biological samples taken from populations living close to the mine compared to controls. Genotoxic and immunotoxic differences were also observed. The results provide evidence of an elevated potential risk to the health of populations, with environmental and occupational exposures resulting from mining activities. Further, the results emphasize the need to implement preventive measures, remediation, and rehabilitation plans for the region.  相似文献   

11.
Ecotoxicology - Gold mining is currently one of the main anthropogenic sources of mercury in the environment. In this study, the total mercury content was measured in bottom sediments, benthic...  相似文献   

12.
Pollen analysis, total phenols content and antioxidant activity were studied for the first time in Portuguese propolis samples from Bornes and Fundão regions. Total phenols content was determined by colorimetric assay and their amount was of 329 mg/g of GAE in Bornes sample and 151 mg/g of GAE in Fundão propolis. The antioxidant capacity of propolis extracts was assessed through the scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) and reducing power of iron (III)/ ferricyanide complex assays. A concentration-dependent antioxidative capacity was verified in DPPH and reducing power assays. Low values of EC50 on DPPH scavenging assay were obtained for Bornes and Fundão propolis (of 6.22 μg/mL and 52.00 μg/mL, respectively). For reducing power the values were 9.00 μg/mL, for Bornes propolis, and 55.00 μg/mL, for Fundão propolis. The high activity of propolis from Bornes could be related with their different pollen composition. The results obtained indicate that Portuguese propolis is an important source of total phenols showing antioxidant properties that could be beneficial for human health.  相似文献   

13.
Over the last several years human sperm quality was found to be significantly reduced and the role environmental contaminants play in this phenomenon remain to be determined. Mercury (Hg) is one of the most widespread contaminants; however the correlation between metal exposure and adverse consequences on human and animals fertility are not completely established. The aim of this study was to determine the effects of direct exposure to inorganic Hg on male gametes using spermatozoa (bovine sperm) which characteristically resemble human sperm. Sperm were divided and incubated for 0.5, 1 or 2 h at low levels of Hg: i) Control: without exposure; ii) Hg8 nM: mercury chloride (HgCl2) at 8 nM and iii) Hg8 μM: HgCl2 at 8 μM. Sperm kinetics, morphology, sperm membrane integrity, and in vitro fertilization were assessed. In addition the levels of reactive oxygen species (ROS), lipid peroxidation and total antioxidant capacity were measured. Hg exposure for 2 h impaired sperm morphology and membrane integrity as well as kinetic parameters including curvilinear velocity and straight-line velocity, which are needed for fertilization as evidenced by the reduced fertilization rate in 8 μM Hg-treated gametes. Hg enhanced oxidative stress in male sperm as reflected by elevated levels of ROS and lipid peroxidation and decreased antioxidant capacity. Data demonstrated that low levels of Hg when incubated with spermatozoa are sufficient to increase oxidative stress, adversely affect sperm quality parameters, subsequently impairing sperm fertility capacity.  相似文献   

14.
Antimicrobial resistance and the mechanisms implicated were studied in 440 enterococci (227 Enterococcus faecium, 177 Enterococcus faecalis, 32 Enterococcus hirae and 4 Enterococcus durans) recovered from 220 faecal samples of healthy humans, poultry and pets in Portugal. Higher levels of resistance were detected for ampicillin, tetracycline, erythromycin and chloramphenicol in poultry isolates (10.5%, 97%, 87.5% and 16%, respectively) compared with human isolates (0%, 26%, 31.5% and 5%, respectively); intermediate levels of resistance for these antibiotics were found in pet isolates. Thirty-three per cent of the E. faecium isolates of poultry origin showed quinupristin/dalfopristin resistance. High-level resistance to gentamicin or streptomycin was detected in 1-7% of isolates in our series of enterococci. The aac(6')-aph(2'), aph(3')-IIIa, erm(B) and tet(M) genes were demonstrated in most of the gentamicin-, kanamycin-, erythromycin- and tetracycline-resistant isolates, respectively. The vat(E) gene was found in 39% of the quinupristin/dalfopristin-resistant E. faecium isolates of poultry origin.  相似文献   

15.
Metallothioneins (MTs) are metal-binding, low molecular weight proteins and are involved in pathophysiological processes like metabolism of essential metals, metal ion homeostasis and detoxification of heavy metals. Metallothionein expression is induced by various heavy metals especially cadmium, mercury and zinc; MTs suppress toxicity of heavy metals by binding themselves to these metals. The aim of this study was to investigate the association between the − 5 A/G metallothionein 2A (MT2A) single nucleotide polymorphism (SNP) and Cd, Zn and Cu levels in the renal cortex from autopsy cases. MT2A core promoter region − 5 A/G SNP was analyzed by PCR-RFLP method using 114 autopsy kidney tissues and the genotype frequencies of this polymorphism were found as 87.7% homozygote typical (AA), 11.4% heterozygote (AG) and 0.9% homozygote atypical (GG). In order to assess the Cd, Zn and Cu levels in the same autopsy kidney tissues, a dual atomic absorption spectrophotometer system was used and the average levels of Cd, Zn and Cu were measured as 95.54 ± 65.58 µg/g, 181.20 ± 87.72 µg/g and 17.14 ± 16.28 µg/g, respectively. As a result, no statistical association was found between the − 5 A/G SNP in the MT2A gene and the Zn and Cu levels in the renal cortex (p > 0.05), but considerably high accumulation of Cd was monitored for individuals having AG (151.24 ± 60.21 µg/g) and GG genotypes (153.09 µg/g) compared with individuals having AA genotype (87.72 ± 62.98 µg/g) (p < 0.05). These results show that the core promoter region polymorphism of metallothionein 2A increases the accumulation of Cd in human renal cortex.  相似文献   

16.
目的 探讨产妇血清促甲状腺激素 (TSH)水平及其新生儿脐血 TSH水平之间的关系。方法 应用放射免疫分析 (RIA)测定了太原市 10 0例顺产产妇血清 TSH含量 ,同时用免疫放射分析 (IRMA)测定了其健康新生儿脐血 TSH含量。结果 产妇血清 TSH均值为 (4.9± 1.4) m U/ L,新生儿脐血 TSH均值为 (8.0±4.9) m U / L ,产妇与其新生儿 TSH水平之间呈显著正相关关系。结论 通过对产妇的 TSH水平的监测 ,可评估新生儿碘营养水平 ,预防和减少甲减弱智儿的出生  相似文献   

17.
18.
This study examines mercury exposure in bats across the northeast U.S. from 2005 to 2009. We collected 1,481 fur and 681 blood samples from 8 states and analyzed them for total Hg. A subset (n = 20) are also analyzed for methylmercury (MeHg). Ten species of bats from the northeast U.S. are represented in this study of which two are protected by the Endangered Species Act (ESA 1973) and two other species are pending review. There are four objectives in this paper: (1) to examine correlates to differences in fur–Hg levels among all of the sampling sites, including age, sex, species, and presence of a Hg point source; (2) define the relationship between blood and fur–Hg levels and the factors that influence that relationship including age, sex, species, reproductive status, and energetic condition; (3) determine the relationships between total Hg and MeHg in five common eastern bat species; and (4) assess the distribution of Hg across bat populations in the northeast. We found total blood and fur mercury was eight times higher in bats captured near point sources compared to nonpoint sources. Blood–Hg and fur–Hg were well correlated with females on average accumulating two times more Hg in fur than males. On average fur MeHg accounted for 86 % (range 71–95 %) of the total Hg in bat fur. Considering that females had high Hg concentrations, beyond that of established levels of concern, suggests there could be negative implications for bat populations from high Hg exposure since Hg is readily transferred to pups via breast milk. Bats provide an integral part of the ecosystem and their protection is considered to be of high priority. More research is needed to determine if Hg is a stressor that is negatively impacting bat populations.  相似文献   

19.
All neonates in the Neonatal Intensive Care Unit (NICU) or during the first days of life undergo painful and stressful procedures. Epidemiologic studies have shown that pain induced by these procedures is not effectively prevented or is inadequately treated. Pain experienced during the neonatal period may lead to negative outcomes, especially in preterm neonates. Prevention is the first step of pain management, and practical guidelines should be used in the NICU. Assessment must be done with adequate tools that take into account the infant's pathology and gestational age. Distinguishing between acute and prolonged pain is important for both assessment and treatment. The most common drugs that have been studied for the treatment of pain and stress are opioids, hypnosedatives, and NMDA receptor antagonists. Morphine and fentanyl are most frequently used for acute or prolonged pain in the NICU. They have potent analgesic effects and few immediate or long-term adverse effects. Midazolam is a commonly used hypnosedative, but its adverse effects limit its use. Drugs such as propofol and ketamine have been used for acute painful procedures; however, further research is needed to assess their long-term effects. Use of non-pharmacologic pain management techniques has increased in recent years. These methods are easy, inexpensive, and effective in helping newborns recover from painful procedures. Sweet solutions and non-nutritive sucking, breastfeeding, skin-to-skin mother care, swaddling, and facilitated tucking are the most commonly employed and evaluated non-pharmacologic methods. Hospitals should promote and improve parent involvement in pain management. In-service education and well organized hospital teams are crucial for successful implementation of pain protocols in newborns.  相似文献   

20.
Propolis is a natural honeybee product known to be beneficial for human health, with a complex chemical composition, highly dependent on the collection site. The objective of the present research was to evaluate phenols and antioxidant activity of propolis samples collected in three main areas of Algarve, South of Portugal. Water revealed to be less effective for extracting phenolic compounds from propolis than the methanol and water/ethanol. The last two were good extraction solvents of phenols. Nevertheless water/ethanol was the solvent chosen because it was able to extract phenols in considerable amounts being less toxic than methanol.  相似文献   

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