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1.
Mol Phylogenet Evol ; 167: 107343, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34748874

RESUMO

Few studies have delimited evolutionary entities within the Sombre Tit, Poecile lugubris. Here, we explored its morphological and genetic variability using 24 morphometric variables, two mitochondrial (COX1 and ND2), two nuclear (ODC and MB), and 10 microsatellite loci. Genetic and morphometric characters supported the species status of the Caspian Tit, Poecile hyrcanus with a separation from P. lugubris more than 4.5 MYA. The phylogenetic analyses uncovered three distinct clades within P. lugubris. The subspecies P. l. lugubris, with strong genetic differences from the other subspecies (4.5%), diverged at ∼1.1 MYA. Samples from Iran formed the remaining two clades. Individuals from western and northwestern Iran were placed in a single clade (anatoliae), while those from southern and southwestern Iran were in another independent clade (dubius-kirmanensis). Morphometric analyses also confirmed this pattern. The microsatellite results discriminated Iranian subspecies as discrete clusters with signs of nuclear admixture between dubius and anatoliae in the Zagros Mountains. Signs of population expansion for anatoliae and dubius-kirmanensis coincided with the late LGM. Our results shed new light on the phylogenetic relationships, evolutionary history, and past demographic processes of P. lugubris.


Assuntos
DNA Mitocondrial , Passeriformes , Animais , DNA Mitocondrial/genética , Humanos , Irã (Geográfico) , Passeriformes/genética , Filogenia , Análise de Sequência de DNA
2.
Environ Sci Pollut Res Int ; 26(25): 25712-25724, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267384

RESUMO

The Caspian Sea is the largest land-locked lake in the world that includes numerous endemic species. Because of its enclosed nature, the pollutants entering this water body become entrapped. The present paper examines the influence of human activity and beach morphology on the abundance and distribution of stranded plastic debris along the Caspian Sea coastlines. It would be possible by relating some characteristics of these beaches (population, urbanization, substrate type, and slope of beaches) with the abundance of plastic debris through a PCo analysis. The results showed that in our study area, the most effective factors on plastic debris distribution were urbanization and population followed by the slope and substrate of beaches. Three size classes of plastic debris were defined as "large microplastic" (1 to < 5 mm), "mesoplastic" (5 to < 25 mm), and "macroplastic" (> 25 mm). The density of the large microplastic, mesoplastic, and macroplastic materials on the Caspian Sea coastline was 8.43 ± 0.54, 8.74 ± 0.42, and 7.53 ± 0.30 particles/m2, respectively. Foam was the most abundant microplastic debris along the study area (47.58%), followed by resin pellets (33.93%) and fragments (16.30%), respectively. We also selected the Boujagh National Park with limited accessibility as an appropriate area for the study of marine debris as one sampling station. Cigarette butts and film pieces displayed a different distribution pattern compared to other debris types in the Boujagh National Park station likely due to their distinct buoyancy specification.


Assuntos
Resíduos/análise , Praias , Mar Cáspio , Monitoramento Ambiental/métodos , Poluentes Ambientais , Atividades Humanas , Humanos , Plásticos , Urbanização
3.
Environ Sci Pollut Res Int ; 26(25): 26090-26101, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31280440

RESUMO

Global DNA methylation, as an epigenetic modifications, can be a promising genomic marker for monitoring the contaminants and predicting their adverse health effects. The study aims to assess the effects of 16 PAH concentration on the altered DNA methylation levels in the kidney and liver of rock pigeon (Columba livia), as a sentinel species, from Tehran megacity as well as 40 days benzo(a)pyrene in vitro exposure: (0.1, 2.5, 5, 7.5, and 10 mg kg-1 bw). Data indicated that the total LMW-PAH (low molecular weight PAHs) group (120.22, 121.34, 103.69, and 128.79 ng g-1 dw in liver, kidney, skin, and muscle, respectively) in the Tehran samples have higher levels than the other PAHs groups. In addition, the DNA methylation level had negative relation with the total amount of PAHs in liver and kidney. A comparatively higher global DNA hypomethylation (by 8.65% in liver and 3.76% in kidney) was observed in birds exposed to B(a)P. Our results lead us to suggest that DNA hypomethylation in liver and kidney associated with the B(a)P may be useful biomarker discovery (more than the amount of PAH concentration in different tissues of C. livia) in urban areas. In conclusion, based on the overall results assessed, DNA methylation changes in pigeon may show a new target pathway for evaluation of environmental health.


Assuntos
Benzo(a)pireno/química , Metilação de DNA/genética , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Columbidae , Monitoramento Ambiental , Irã (Geográfico) , Hidrocarbonetos Policíclicos Aromáticos/química , Espécies Sentinelas
4.
J Toxicol Environ Health A ; 78(5): 342-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25734629

RESUMO

Because mercury (Hg) is released into the atmosphere, wildlife living in habitats located far from point sources of metal may still be at risk. Mercury accumulation, previously considered a risk for aquatic ecosystems, is also found in many wildlife terrestrial species. The aim of the present study was to examine total Hg concentrations in the brown bear (Ursus arctos) by measurement of metal in hair from museum collections in Iran. Another objective of this investigation was to characterize the risk of Hg exposure in bears in several parts of Iran. Brown bear (Ursus arctos) hair samples (n = 35) were collected from 14 provinces in Iran for analysis of Hg contamination, performed using an advanced mercury analyzer (model Leco 254 AMA, USA) according to ASTM standard D-6722. Total Hg levels in Iranian bears from all areas ranged from 115.81 to 505.82 µg/kg, with a mean of 193.39 ng/g. Mercury concentrations in brown bear hair from different provinces in Iran were as follows in descending order: Khorasan Razavi > Esfahan > Khozestan > Yazd > Lorestan > Charmahalva Bakhtiari > Bushehr > Mazandaran > Markazi > Tehran > Ardebil > Gilan > East Azerbaijan. The highest content of Hg was found in the south (206.62 ± 31.95 ng/g), whereas the lowest levels were detected in the west (167.71 ± 32.97 ng/g). Overall total Hg content in bear hair was below harmful levels for this species. A decreasing trend was noted in the period 1986-2006, which may be mainly due to reduction of global Hg emissions. Data suggest that food habits and habitat are two important factors that influence Hg accumulation in bears.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Mercúrio/análise , Ursidae/metabolismo , Animais , Cabelo/química , Irã (Geográfico) , Estudos Retrospectivos , Medição de Risco
5.
Environ Monit Assess ; 187(1): 4082, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25492705

RESUMO

The Hara Mangrove Forest of the Persian Gulf is undergoing increasing pollution from industrial, municipal, and petroleum sources; however, little research in ecotoxicology has been carried out in this ecosystem. In the present study, mercury distribution and accumulation were investigated in muscle, liver, kidney, and feather of the resident Western reef heron (n = 15) and the migratory Siberian gull (n = 15). We also evaluated the relation between Hg concentrations, sex, and age (juvenile vs. adult). Results showed that the highest concentrations of Hg were recorded in the feather (35 ± 0.14-3.0 ± 0.27 mg kg(-1) dw) and at 3.7-, 1.6-, and 1.3-fold in muscle, kidney, and liver, respectively. Concentrations of mercury in tissues of migratory birds were two times higher than in resident birds; geographical differences and feeding habits were used to explain these variations. We found a weak relationship between Hg concentrations in feathers and internal tissues (r ≤ 0.50); conversely, liver presented strong positive correlations with other soft tissues, especially kidney (p > 0.05; r = 0.82). Results showed that sex and age have no significant effects on T-Hg accumulation in these birds (p > 0.05; r < -0.01). Based on these findings, Hg concentrations were low in both species. Therefore, Hg contamination of this aquatic ecosystem is not a threat. Accordingly, we recommend the use of the Western reef heron as a bioindicator of mercury pollution in this region.


Assuntos
Aves/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Áreas Alagadas , Migração Animal , Animais , Charadriiformes/metabolismo , Ecotoxicologia , Poluentes Ambientais/análise , Poluição Ambiental , Plumas/química , Plumas/metabolismo , Feminino , Oceano Índico , Rim/metabolismo , Fígado/metabolismo , Masculino , Mercúrio/análise
6.
Biol Trace Elem Res ; 148(3): 292-301, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22419376

RESUMO

Our aim for carrying out this study was to estimate the levels of mercury in the hair of pregnant women and its association with fish consumption and amalgam fillings. From November 2007 to January 2008, 100 hair samples were collected randomly from three groups of pregnant women: Ahvaz in the south of Iran, Noushahr in the north, and the countryside of Noushahr. Significant differences were found in these three groups of pregnant women's samples (p>0.05). The mean mercury level in women's hair was found to be 0.37 µg/g (range, 0.11-3.57 µg/g). Only in 2 % of collected hair samples did the total mercury (THg) level exceed the United States Environmental Protection Agency-recommended 1.0 µg/g. In addition, there was a positive correlation of THg content in Ahvaz group's samples with respect to fish consumption (r=0.41, p=0.02) and a negative correlation of THg content in those who consumed vegetables and fruit. The level of education also played an indicating factor in this group. Moreover, significant association was found between the residence time and Hg concentration of women's hair samples collected from Noushahr (p>0.05). Similarly, the same correlations were found between hair mercury levels and the time since the first filling, number of dental fillings, pregnancy interval, and lactating period.


Assuntos
Amálgama Dentário/toxicidade , Dieta , Cabelo/química , Lactação/fisiologia , Mercúrio/análise , Feminino , Humanos , Irã (Geográfico) , Gravidez
7.
Environ Monit Assess ; 184(1): 375-80, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21494835

RESUMO

Human milk is usually the only source of food for infants during the first 4 to 5 months of their life. Maternal environmental mercury exposure is directly related to fish consumption or amalgam filling. In this research, 38 human milk samples were collected from mothers of Lenjan area who were not occupationally exposed with mercury. Mercury concentration in human milk was determined by AMA254 Mercury Analyzer. A level of mercury was examined in relation to somatometric, demographic and dental amalgam parameters. Obtained results showed that only dental amalgam significantly increased the mercury level in human milk (p < 0.001). The mean mercury concentrations in milk of mothers without teeth fillings (n = 13), with one to three teeth fillings (n = 10), and four to eight teeth fillings (n = 15) were 2.87, 5.47, and 13.33 µg/l, respectively. The result of this study also showed a positive correlation of mercury milk levels with the number of teeth fillings of the mother (p < 0.05, r = 0.755). The estimated weekly intake of mercury of a breastfed infant in this study was, in some cases, higher than provisional tolerance weekly intake recommended by FAO/WHO, which pose a threat to their health.


Assuntos
Amálgama Dentário/química , Mercúrio/química , Leite Humano/química , Humanos , Irã (Geográfico) , Mercúrio/metabolismo
8.
Ecotoxicology ; 19(6): 997-1002, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20596768

RESUMO

An evaluation of suitability of applying hair as a noninvasive indicator for determination of the body burden mercury in mammals was carried out by determining the concentration of mercury in hair and liver tissue of the golden jackal, Canis aureus . Nineteen jackals killed on the roads along the Caspian Sea in the central region of Mazandaran Province, Iran were collected. The mercury measurements were carried out by AMA254 LECO and the standard method ASTM-D6722. SPSS and Excel were used for analytical statistics. There was a significant difference in Hg levels between the hair and liver tissue (P < 0.001). The average concentration of mercury was 187.3 + or - 22.7 and 53.3 + or - 7.3 ng/g, respectively. No significant differences were seen either between the sexes or in correlation between the tissues. But a significant and positive relation was seen between the mercury content in hair and body weight and length (P < 0.005). In general, the mercury concentration was less than the deleterious, effective limit on the species. It seems that this is the first study of Hg concentrations in jackals and demonstrates on easy and noninvasive sampling method.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Cabelo/metabolismo , Chacais/metabolismo , Mercúrio/metabolismo , Animais , Tamanho Corporal , Feminino , Chacais/anatomia & histologia , Fígado/metabolismo , Masculino
9.
Bull Environ Contam Toxicol ; 84(6): 716-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20424818

RESUMO

In this study, the mercury concentrations of liver, breast feathers and tail feathers in three species of Gull; Black-headed Gull (Larus ridibundus), Common Gull (Larus canus) and Little Gull (Larus minutus) from the South coast of the Caspian Sea in Iran were assayed. Mercury accumulation in liver, breast feathers and tail feathers of species were 1.69-3.16, 2.88-7.18 and 2.09-5.66 mg/kg, respectively. Mercury concentration hierarchy in tissues we tested was as follows: breast feather > tail feather > and liver. We found that despite its small size, Little Gull had highest (3.85-8.05 mg/kg) and Common Gull lowest (1.69-2.88 mg/kg) level of Hg in their bodies. An inverse relationship between body size and Hg levels in these Gulls was detected. Mercury in Little Gull and Black-headed Gull exceeded the 5 ppm threshold for adverse effect.


Assuntos
Charadriiformes/metabolismo , Poluentes Ambientais/análise , Mercúrio/análise , Animais , Monitoramento Ambiental , Poluentes Ambientais/farmacocinética , Plumas/metabolismo , Irã (Geográfico) , Fígado/metabolismo , Mercúrio/farmacocinética , Oceanos e Mares , Especificidade da Espécie , Distribuição Tecidual
10.
Bull Environ Contam Toxicol ; 84(5): 577-81, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20419290

RESUMO

Levels of organochlorine pesticides (OCPs) and PCB were determined in three duck species: Pintail (Anas acuta), Common Teal (Anas creaca), and Mallard (Anas platyhynchos). Both persistent organochlorines were more abundant in muscle than in the liver; Mallard had the highest levels of PCBs [84.0 +/- 39.0 ng/g wet weight (ww)], and Common Teal showed the highest levels of DDTs (561.0 +/- 220.0 ng/g ww). This exposure level is more than two orders of magnitude below provisional tolerable daily intake (PTDI) (0.01 mg/kg bw for DDT and its associated compounds) of The Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO).


Assuntos
Patos/fisiologia , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Animais , Animais Selvagens , Monitoramento Ambiental , Contaminação de Alimentos/prevenção & controle , Hidrocarbonetos Clorados/metabolismo , Irã (Geográfico) , Fígado/química , Fígado/metabolismo , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Resíduos de Praguicidas/metabolismo , Especificidade da Espécie
11.
Bull Environ Contam Toxicol ; 84(3): 326-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20098979

RESUMO

Persian Gulf supports diverse ecosystems and biota in need of remediation and protection, and metal data from this region is needed. Mercury (Hg) in tissues of three waders (Black-winged Stilt Himantopus himantous, Red-wattled Plover Hoplopterus indicus, and White-tailed Plover Vanellus leucurus) from Shadegan Wetlands is reported. Black-winged Stilt had higher Hg in feather (6.6 +/- 0.6 microg/g dry weight), liver (3.5 +/- 1 microg/g dry weight), kidney (4.5 +/- 0.8 microg/g dry weight) and muscle (1.2 +/- 0.2 microg/g dry weight) (not statistically significant). Differences in Hg among waders could have resulted from diverse feeding habitats and dissimilar foraging sites.


Assuntos
Aves/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Animais , Oceano Índico , Mercúrio/farmacocinética , Distribuição Tecidual , Poluentes Químicos da Água/farmacocinética
12.
Environ Res ; 109(7): 830-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19665701

RESUMO

In the present study, the first baseline concentration of mercury (Hg) in different species of Iranian birds was investigated. From April to October 2005, the tail feathers of 100 birds belonging to 27 species (14 families) from different places in southwest Iran (Khuzestan to Persian Gulf) were collected. The Hg levels were evaluated in relation to taxonomic affiliation and trophic level (type of food). The results showed that the Hg levels in the feathers were between 0.07 and 4.71mg/kg dry weight (dw), and there was a significant effect of taxonomic groups in relation to Hg concentration (p<0.001). The highest mercury concentrations were in Laridae and Ciconidae. Alcedinidae had intermediate values, whereas Upupidae, Glareolidae, Scolopacidae, Turdidae, Ardeidae, Anatidae were in subsequent orders; and the lowest concentrations of Hg were in Rallidae, Cuculidae, Pycnonotidae, Corvidae and Columbidae. The results indicated a significant difference between the trophic levels (p<0.001). Fish predators had the highest level of Hg (3.07mg/kg). Invertebrate predators and herbivorous birds had the lowest concentration of Hg (0.84 and 0.64mg/kg, respectively), whereas crab and fish predators and omnivorous birds had moderate values (1.73 and 1.70mg/kg, respectively). In the present study, the concentration of Hg was significantly higher in tail feathers than in primary and secondary (p<0.001). A significant positive correlation among Hg concentration of feather types was observed (r>0.96). The results obtained in this study indicated that among 100 birds tested, 6% of them had Hg concentrations greater than 5mg/kg in feather (adverse level).


Assuntos
Aves/metabolismo , Ecotoxicologia/métodos , Plumas/metabolismo , Mercúrio/farmacocinética , Animais , Classificação , Monitoramento Ambiental/métodos , Plumas/química , Cadeia Alimentar , Irã (Geográfico) , Mercúrio/análise , Estatísticas não Paramétricas
13.
Bull Environ Contam Toxicol ; 82(4): 450-3, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19142558

RESUMO

We document mercury distribution in tissues of two waterfowls; moorhen (Gallinula chloropus; n=6), and Common Teal (Anas crecca; n=6) from Shadegan wetlands in Southwestern Iran. Mean value of mercury in moorhen liver was (0.36 Hg microg g(-1) dry weight), Common Teal had (4.34 Hg microg g(-1) dry weight) mercury. In all tissues, Common Teals had significantly higher mercury concentrations than moorhens (U test, p

Assuntos
Patos , Galliformes , Compostos de Mercúrio/metabolismo , Áreas Alagadas , Migração Animal , Animais , Plumas/química , Plumas/metabolismo , Irã (Geográfico) , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Compostos de Mercúrio/análise , Músculo Esquelético/química , Músculo Esquelético/metabolismo
14.
Ecotoxicology ; 18(3): 319-24, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19031116

RESUMO

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.


Assuntos
Aves/metabolismo , Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Mercúrio/análise , Análise de Variância , Animais , Plumas/química , Feminino , Irã (Geográfico) , Rim/química , Fígado/química , Masculino , Músculo Esquelético/química , Espectrofotometria Atômica
15.
Arch Environ Contam Toxicol ; 56(4): 803-10, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18758700

RESUMO

Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha-, beta-, and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153, and 180) were determined in tail feathers from 35 birds belonging to 15 species, all originating from the southwest of Iran (Khuzestan, coast of the Persian Gulf) and kept in museum collections. The patterns of organochlorine contaminants (OCs) in birds varied depending on their migratory behavior. Resident birds contained higher median PCB concentrations (

Assuntos
Migração Animal , DDT/metabolismo , Plumas/metabolismo , Hexaclorocicloexano/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Animais , Aves , Cromatografia Gasosa , DDT/análise , Monitoramento Ambiental/métodos , Plumas/química , Hexaclorocicloexano/análise , Irã (Geográfico) , Praguicidas/análise , Bifenilos Policlorados/análise
16.
Environ Int ; 35(2): 285-90, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18718664

RESUMO

Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha, beta and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153 and 180), were determined in tail feathers from 37 birds belonging to 18 species, all originating from the South-West of Iran (Khuzestan, coast of the Persian Gulf). This is the first report on organochlorine contaminants in feathers from museum collections and it is an indication of the concentrations of OCPs and PCBs in the past (1991-1996). Median concentrations of HCHs, DDTs, PCBs and HCB were 22, 14, 11 and 10 ng/g feather, respectively. Significant correlations (p<0.05) were calculated between OCPs (except HCB) and PCBs in the bird feathers. p,p'-DDE and gamma-HCH were the most abundant OCPs, while CB 180, CB 138 and CB 101 were the predominant PCB congeners in almost all species. Significant differences (p<0.05) in the mean concentrations of DDTs and PCBs were detected among species grouped according to their feeding habits. Levels of DDTs and PCBs were highest in the carnivorous species and lowest in the herbivorous species. Levels of OCPs and PCBs in feathers of bids in the 1990s were generally below the thresholds reported to affect reproduction.


Assuntos
Plumas/química , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Animais , Aves , Exposição Ambiental , Irã (Geográfico)
17.
Sci Total Environ ; 381(1-3): 59-67, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17490727

RESUMO

The purpose of the study was to evaluate the environmental and occupational exposure to mercury (Hg), and to examine the various parameters, which contribute to high levels of mercury of Iranian dentists in Tehran. One-hundred hair and nail samples were collected from dentists. In addition, fifty samples from a control group and twenty-five additional samples from dental nurses were taken for comparison. The survey included a structured questionnaire designed to provide information about the parameters that influenced their occupational and environmental exposure to Hg. Overall mean concentrations in the hair and nails of the dentists was 2.84+/-0.47 and 3.56+/-0.53 mg/kg dry wt respectively. The equivalent values were 0.61+/-0.07 mg/kg in hair and 0.39+/-0.06 mg/kg in nails for the control group. In addition, mean concentrations in the dental nurses were 0.92+/-0.23 and 1.77+/-0.51 mg/kg in hair and nails respectively. The study showed that use of masks had a significant effect on Hg levels (p=0.02 for hair and p=0.03 for nails) and use of gloves only had significant effect on nails Hg (p=0.05). Hg concentrations in nails were significantly lower among the dentists who always used gloves and masks. Also, fish consumption and number of patients visited per day had a significant effect on hair (p=0.02 and p=0.02 respectively) and nails (p=0.03 and p=0.02 respectively) Hg. On the other hand, there was a significant effect of age in relation to Hg concentration in the hair and nails of the dentists (p=0.006 for hair and p=0.01 for nails). Multiple regressions were computed between hair Hg and the various assessed variables. The only positive results were between Hg concentration and masks for the dentists (p=0.03), and Hg concentration and the number of fish meals for the control group (p=0.009).


Assuntos
Odontólogos , Mercúrio/análise , Exposição Ocupacional/análise , Adulto , Animais , Amálgama Dentário/química , Assistentes de Odontologia , Dieta , Monitoramento Ambiental , Feminino , Peixes , Luvas Cirúrgicas , Cabelo/química , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Unhas/química , Roupa de Proteção , Análise de Regressão
18.
Environ Res ; 104(2): 258-65, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17307157

RESUMO

This paper presents the levels of mercury (Hg) in tail feathers from different species of birds, in southwest Iran (Khuzestan to Persian Gulf). Between April and October 2005, we collected tail feathers from 77 birds belonging to 18 species, mostly raptor birds. The birds were collected for the Museum Natural History, Faculty of Natural Resources and Marine Sciences of Tarbiat Modares University. Hg concentrations were evaluated in relation to taxonomic affiliation and trophic level. Feather Hg concentrations ranged from 0.09 to 2.01 mg/kg dry wt. We found a significant difference in feather Hg concentrations across taxonomic groups (p<0.001) with highest concentrations in common kestrel and saker falcon (Falconidae) (1.87 mg/kg) followed by greater spotted eagle, sparrowhawk, goshawk, griffon vulture, buzzards, marsh harrier (Accipiteridae) and owls (Strigidae). Blue-cheeked bee-eater (Meropidae) had intermediate values, followed by European roller (Coraciidae), and lapwing (Charadiidae), whereas black francolin, see-see patridge and chukar (Phasianidae) (0.18 mg/kg) contained the least amount of Hg. There was a significant difference in feather Hg concentrations in relation to trophic levels, at confidence level of 99% (p<0.001). There was an increased pattern in the amount of mercury from herbivorous birds up to vertebrate predators, so that the amount of mercury in vertebrate predators (1.30 mg/kg) was more than 1.5 times as much of the invertebrate predators (0.7 mg/kg) and more than 6 times as much of the herbivorous birds (0.18 mg/kg). We also measured Hg levels in secondary feathers of raptor birds. Paired samples t-test showed that the concentrations of mercury were significantly higher (p<0.001) in the tail feathers (1.2mg/kg) than secondary (0.71 mg/kg). However, Hg levels are below the range found by other authors to cause behavioral change or reduce reproduction (5mg/kg). It seems that exposure of some birds with mercury for a long time causes their high concentration of mercury.


Assuntos
Aves/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Plumas/química , Mercúrio/análise , Animais , Poluentes Ambientais/farmacocinética , Plumas/metabolismo , Irã (Geográfico) , Mercúrio/farmacocinética , Medição de Risco , Especificidade da Espécie
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