scholarly journals Children with amalgam dental restorations have significantly elevated blood and urine mercury levels

2021 ◽  
Author(s):  
Lei Yin ◽  
Simon Lin ◽  
Anne O Summers ◽  
Van Roper ◽  
Matthew J Campen ◽  
...  
Keyword(s):  
Methyl Mercury ◽  
Large Scale ◽  
Total Mercury ◽  
Age Groups ◽  
Inorganic Mercury ◽  
Striking Difference ◽  
Seafood Consumption ◽  
Dental Restorations ◽  
Mercury In Urine ◽  
And Gender

Abstract Human exposure to organic mercury (Hg) as methylmercury (MeHg) from seafood consumption is widely considered a health risk because pure methylmercury is extremely neurotoxic. In contrast, the clinical significance of Hg exposure from amalgam (AMG) dental restorations, the only other major non-occupational source of Hg exposure, has long been debated. Here we examined data from the two most recent National Health and Nutrition Examination Surveys (NHANES) on 14,181 subjects to assess the contributions of seafood consumption versus AMG to blood total mercury (THg), inorganic mercury (IHg), and methyl mercury (MeHg) and to urine creatinine corrected mercury (UTHg). All subjects were also classified as to their self-reported qualitative consumption of seafood (59% fish and 44% shellfish). Subjects with restorations were grouped into three groups, (0) those without AMG (64.4%), (1) those with 1-5 dental AMG restorations (19.7%), (2) those with more than five AMG (16%). Seafood consumption increased total mercury in urine (UTHg) and total mercury (THg) and methyl mercury (MeHg) in blood, but unlike AMG, seafood did not increase blood inorganic mercury (IHg). Using stratified covariate (ANOVA) and multivariate (GLM) analyses revealed a strong correlation of blood (THg and IHg) and urine (UTHg) levels with the number of AMGs. In a subpopulation without fish consumption, having more than five AMG restorations raised blood THg (103%), IHg (221%), and urine UTHg (221%) over the group without AMG. The most striking difference was noted in classification by age: subjects under six years old with more than five AMG restorations had the highest blood IHg and urine UTHg among all age groups. Elevation of bivalent IHg on a large scale in children warrants urgent in-depth risk assessment with specific attention to genetic- and gender-associated vulnerabilities.

scholarly journals Determination of methyl mercury and total mercury in sediment samples collected from canals in HoChiMinh city

2016 ◽  
Vol 19 (4) ◽  
pp. 123-136
Author(s):  
Hien Thai Hoang ◽  
Dong Van Nguyen
Keyword(s):  
Reference Material ◽  
Analytical Method ◽  
Methyl Mercury ◽  
Total Mercury ◽  
Inorganic Mercury ◽  
Absorption Spectrometry ◽  
Internal Reference ◽  
Atomic Fluorescence ◽  
Sediment Samples ◽  
Cold Vapour

In this study, the analysis of methyl mercury (MeHg) and total mercury (T-Hg) was studied using gas chromatographic separation/atomic fluorescence spectrometric detection and cold vapour atomic absorption spectrometry respectively. MeHg was extracted from sediment matrix using HNO3/KCl/CuSO4 into dichloromethane followed ethylation with NaB(C2H5)4 in hexane. Total mercury was digested using three different procedures: EPA 245.1, AOAC 971.21 and our proposed one. The reliability of the analytical method for MeHg was evaluated by the use of the certified reference material ERM CC-580. In addition, the analytical method for total merury was evaluated using a fresh water sediment as an internal reference material, spiked with inorganic mercury, methyl mercury and phenyl mercury. The method detection limits for MeHg and total mercury were 0.08 and 0.15 ng/g (as Hg), respectively. The established analytical methods were applied to analyse MeHg and total mercury in sediment samples collected from canals and rivers in Hochiminh City. The concentrations of methyl mercury and total mercury in sediment samples were 0.08–2.87 ng/g và 14 – 623 ng/g (as Hg, dw). [MeHg]/Σ[Hg] respectirely were in a range of 0.1–2.3 %, which was in good agreement with the published ratios in sediment samples. A good correlation between the concentration of MeHg with total mercury and total organic carbon contents in the studied sediment samples was found.

Total Mercury, Inorganic Mercury and Methyl Mercury Determination in Red Wine

2011 ◽  
Vol 5 (3) ◽  
pp. 505-511 ◽  
Author(s):  
Valderi Luiz Dressler ◽  
Clarissa Marques Moreira Santos ◽  
Fabiane Goldschmidt Antes ◽  
Fabrina Regia Stum Bentlin ◽  
Dirce Pozebon ◽  
...  
Keyword(s):  
Methyl Mercury ◽  
Total Mercury ◽  
Red Wine ◽  
Inorganic Mercury ◽  
Mercury Determination

Determination of Methyl Mercury in Fish by Flameless Atomic Absorption Spectroscopy and Comparison with an Acid Digestion Method for Total Mercury

1976 ◽  
Vol 59 (1) ◽  
pp. 153-157
Author(s):  
Jurgen L Kacprzak ◽  
Ramon Chvojka
Keyword(s):  
Atomic Absorption ◽  
Absorption Spectroscopy ◽  
Atomic Absorption Spectroscopy ◽  
Methyl Mercury ◽  
Total Mercury ◽  
Inorganic Mercury ◽  
Flameless Atomic Absorption ◽  
Flameless Atomic Absorption Spectroscopy ◽  
The Difference

Abstract A method for the concurrent determination of methyl mercury and inorganic mercury by flameless atomic absorption spectroscopy (AAS) is described. Fifty-seven samples of juvenile black marlin fish were analyzed for inorganic and methyl mercury, and total mercury was calculated by addition of the 2 values. The sensitivity of the method was estimated to be 0.029 μg for inorganic mercury and 0.033 μg for methyl mercury. The detection limit of the method was about 0.02 μg inorganic mercury or methyl mercury and the error of the method was found not to exceed 10% for samples giving about 10% deflection on the absorbance scale. Samples from the same fish were analyzed by a commonly accepted flameless AAS method for the determination of total mercury. When the results for total mercury from the 2 methods were statistically compared, using a paired t-test, the difference between the results obtained by the 2 methods was found to be insignificant at the 95% confidence level.

Modified determination of total and inorganic mercury in urine by cold vapor atomic absorption sectrometry.

1976 ◽  
Vol 22 (10) ◽  
pp. 1719-1723 ◽  
Author(s):  
D Littlejohn ◽  
G S Fell ◽  
J M Ottaway
Keyword(s):  
Total Mercury ◽  
Chemical Reduction ◽  
Inorganic Mercury ◽  
Elemental Mercury ◽  
Mercury Vapor ◽  
Storage Conditions ◽  
Single Beam ◽  
A Value ◽  
Cold Vapor Atomic Absorption ◽  
Mercury In Urine

Abstract In this procedure a single-beam spectrophotometer is used without background correction. By the method of Magos [Analyst (London) 96, 847 (1971)] mercury in undigested urine is complexed to L-cysteine in acid solution. At high pH and in the presence of stannous ions, mercury ions are reduced to elemental mercury. The mercury vapor is partitioned above the reagent solution in a specially designed chemical reduction apparatus similar in principle to that used by Kubasik et al. [Clin. Chem. 18, 1326 (1972)]. The vapor is then flushed by air through an "absorption" cell, where the absorption of the mercury line at 253.7 nm is measured. The value obtained for inorganic mercury subtracted from that for total mercury gives a value for organic mercury. CV's for the inorganic mercury procedure at 40 and 5 mug/liter concentrations were 3.1% and 7.5%, respectively. The detection limit is 0.82 mug/liter. The CV for the total-mercury procedure (20 mug/liter) was 2.6%. Mean analytical recoveries of organic and inorganic mercury were 96.5% and 101%, respectively. We investigated storage conditions for urine and compared results by the present technique with those by activation analysis. Our method is a convenient way to screen individuals who have been exposed to a mercury hazard.

scholarly journals Occurrence of Four Dengue Virus Serotypes and Chikungunya Virus in Kilombero, Tanzania during Dengue Outbreak in 2018

2020 ◽  
Author(s):  
Beatrice Chipwaza ◽  
Robert David Sumaye ◽  
Maja Weisser ◽  
Winfrid Gingo ◽  
Nicholas Kim-Wah Yeo ◽  
...  
Keyword(s):  
Large Scale ◽  
Age Groups ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Denv Serotypes ◽  
First Occurrence ◽  
Dry Seasons ◽  
Dengue Virus Serotypes ◽  
And Gender ◽  
Dry And Rainy Seasons

AbstractBackgroundDengue and Chikungunya viruses can cause large-scale epidemics with attack rates exceeding 80%. In Tanzania, there have been repeated outbreaks of dengue fever, the most recent one in 2018 and 2019 mostly reported in coastal areas. Despite its importance, there is limited knowledge on epidemiology of dengue (DENV) and chikungunya (CHIKV) in Tanzania. This study was conducted to investigate the prevalence of DENV and CHIKV in Kilombero district, South-Eastern Tanzania.MethodsA cross-sectional study was conducted at Kibaoni Health Center, in Kilombero district, in the rainy and dry seasons of 2018. Febrile patients of any age and gender were enrolled. Blood samples were taken and screened for DENV and CHIKV viral RNA by real-time RT-PCR assays.ResultsA total of 294 patients were recruited. Most were females (65%), and aged between 14⍰25 years (33%). DENV and CHIKV were detected in 29 (9.9%) and 3 (1.0%) patients, respectively. DENV was detected across all age groups and during both dry and rainy seasons. Although all four DENV serotypes were detected, serotypes 1 and 3 dominated and were present in 14 patients (42.4%) each. Additionally, the study showed DENV-1 and DENV-3 co-infections.ConclusionThis study reveals the co-circulation of all four DENV serotypes and CHIKV in Kilombero district. Importantly, we report the first occurrence of DENV-4 in Tanzania. Unlike previous DENV outbreaks caused by DENV-2, the 2018 outbreak was dominated by DENV-1 and DENV-3. Occurrence of all serotypes suggests the possibility of having severe clinical outcomes in future DENV epidemics in Tanzania.

scholarly journals Features of social and psychological adaptation in patients with depressive disorders

2021 ◽  
Keyword(s):  
Large Scale ◽  
Depressive Disorders ◽  
Age Groups ◽  
Psychological Adaptation ◽  
Diagnostic Techniques ◽  
External Control ◽  
Self Acceptance ◽  
And Gender ◽  
Gender Factor ◽  
Integrated Indicators

The problem of depressive disorders is one of the key problems of modern psychiatry due to the high prevalence, large-scale social losses and negative medical consequences of depression, as well as severe dysfunction of patients, which determines the relevance of the study of socio-psychological adaptation in depressive disorders. The aim of the study: to determine the features of socio-psychological adaptation in patients with depressive disorders, taking into account age and gender Objectives of the study: to define the structure and quantitative indicators of socio-psychological adaptation and analyze its features in patients with depressive disorders in different age groups and taking into account the gender factor. Methods: using diagnostic techniques for socio-psychological adaptation C. Rogers et R.F. Dymond clinically and psychologically examined 107 men and 138 women with depressive disorders. Results. It was found that patients with depressive disorders are characterized by a low level of socio-psychological adaptation, while men have indicators of socio-psychological adaptation are significantly lower than women in terms of adaptability, self-acceptance, acceptance of others, emotional comfort, adaptation, self-acceptance, acceptance of others, as well as on integrated indicators of emotional comfort and internality. Indicators of maladaptation are higher in men than in women: maladaptation, self-rejection, rejection of others, emotional discomfort and external control. There is a tendency to decline the state of socio-psychological adaptation with age, which is manifested by a decrease in older age groups of adaptability, self-acceptance, emotional comfort, adaptation, self-acceptance, and integrated indicators of emotional comfort and internality, and increasing indicators of maladaptation, self-rejection, rejection, external control, payroll and escapism. The most significant violation of socio-psychological adaptation occurs in the age group of 45 years and older.

scholarly journals Why the English–Wabigoon river system is still polluted by mercury 57 years after its contamination

FACETS ◽  
2021 ◽  
Vol 6 ◽  
pp. 2002-2027
Author(s):  
John W.M. Rudd ◽  
Carol A. Kelly ◽  
Patricia Sellers ◽  
Robert J. Flett ◽  
Bruce E. Townsend
Keyword(s):  
Surface Sediment ◽  
Methyl Mercury ◽  
Total Mercury ◽  
Inorganic Mercury ◽  
River System ◽  
Lake Surface ◽  
Riverbank Erosion ◽  
Plant Site ◽  
High Mercury ◽  
Mercury Production

Between 1962 and 1969, 10 tonnes of mercury were discharged from a chlor-alkali plant in Dryden, Ontario, to the English–Wabigoon River. Present-day fish mercury concentrations are amongst the highest recorded in Canada. In 2017, the Grassy Narrows Science Team found no evidence of ongoing discharges from the plant site to the river water, even though large quantities of mercury remain at the site. Instead, our data suggest that ongoing erosion of high mercury particles by the river, as it meanders through contaminated floodplains, is responsible for present-day transport of mercury to Clay Lake and to Ball Lake, located 154 km downstream. In Clay Lake, surface sediment total mercury concentrations and inflow water concentrations are still about 15 times above background (86 km downstream), and in Ball Lake mercury concentrations in sediments appeared to be still increasing. The remobilization of legacy inorganic mercury from riverbank erosion between Dryden and Clay Lake stimulates methyl mercury production there, in Clay Lake, and in Ball Lake. The large quantities of methyl mercury produced between Dryden and Clay Lake are mostly dissolved in water and are swept downstream, elevating concentrations in water and biota throughout the system. Several options for remediating the ongoing contamination are discussed.

A Dynamic Relationship Between Methyl Mercury, Inorganic Mercury, and Total Mercury in Umbilical Cord Blood

Epidemiology ◽  
2009 ◽  
Vol 20 ◽  
pp. S89
Author(s):  
Ellen M Wells ◽  
Jeff Jarrett ◽  
Carl P Verdon ◽  
Kathleen L Caldwell ◽  
Ana Navas-Acien ◽  
...  
Keyword(s):  
Cord Blood ◽  
Umbilical Cord ◽  
Umbilical Cord Blood ◽  
Methyl Mercury ◽  
Total Mercury ◽  
Inorganic Mercury ◽  
Dynamic Relationship

scholarly journals Occurrence of Four Dengue Virus Serotypes and Chikungunya Virus in Kilombero Valley, Tanzania during Dengue Outbreak in 2018

2020 ◽  
Author(s):  
Beatrice Chipwaza ◽  
Robert David Sumaye ◽  
Maja Weisser ◽  
Winfrid Gingo ◽  
Nicholas Kim-Wah Yeo ◽  
...  
Keyword(s):  
Large Scale ◽  
Age Groups ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Denv Serotypes ◽  
Kilombero Valley ◽  
First Occurrence ◽  
Dry Seasons ◽  
Dengue Virus Serotypes ◽  
And Gender

Abstract Background Dengue and Chikungunya viruses can cause large-scale epidemics with attack rates up to 80%. In Tanzania, there have been repeated outbreaks of dengue fever, the most recent one in 2018 and 2019, mostly affecting the coastal areas. Despite its importance, there is limited knowledge on epidemiology of dengue (DENV) and chikungunya (CHIKV) in Tanzania. This study was conducted to investigate the prevalence of DENV and CHIKV in Kilombero valley, Tanzania. Methods A cross-sectional study was conducted at Kibaoni Health Center, in Kilombero valley, South-eastern Tanzania in the rainy and dry seasons of 2018. Febrile patients of any age and gender were enrolled from the outpatient department. Blood samples were taken and screened for DENV and CHIKV viral RNA by real-time RT-PCR assays. Results Overall, 294 patients were recruited. Most were females (65%),and one third of patients aged between 14─25 years. DENV and CHIKV were detected in 29(9.9%) and 3(1.0%) patients, respectively. DENV was detected across all age groups during both dry and rainy seasons. Although all four DENV serotypes were detected, serotypes 1 and 3 dominated and were present in 14 patients (42.4%) each. Additionally, the study showed DENV-1 and DENV-3 co-infections. Conclusion This study reveals the co-circulation of all four DENV serotypes and CHIKV in Kilombero. Importantly, we report the first occurrence of DENV-4 in Tanzania. Unlike previous DENV outbreaks caused by DENV-2, the 2018 outbreak was dominated by DENV-1 and DENV-3. Occurrence of all serotypes suggests the possibility of severe clinical outcomes in future DENV epidemics in Tanzania.

Gender, Age, and Ethnicity in Immigration for an Australian Nation

1997 ◽  
Vol 29 (2) ◽  
pp. 217-236 ◽  
Author(s):  
R Fincher
Keyword(s):  
Large Scale ◽  
Age Groups ◽  
National Development ◽  
Skilled Workers ◽  
World War ◽  
World War 2 ◽  
Gender And Age ◽  
Permanent Migration ◽  
And Gender ◽  
Ethnicity And Gender

Since the Second World War, large-scale immigration has been promoted by successive Australian governments as vital to national development. Most accounts of the content and implementation of the resulting immigration policies, particularly until the demise of the White Australia policy in 1972, have emphasised their racism. The ideal immigrant under these policies, however, was not merely of particular birthplace and ethnicity, but also had specified gender and age characteristics. The author proposes that selection of immigrant settlers in Australia since World War 2 has been gendered as well as racialised, often combining particular sexisms with particular racisms and specifying the ways that ethnicity and gender should coexist in immigrants of different age groups. She notes implications for immigrants once in Australia (especially women) of the category under which they have entered the country. And she suggests that a new phase relating immigration to redefinition of the Australian nation, in which the temporary migration of skilled workers is preferred to their permanent migration, may be beginning; a phase whose modes of regulation and outcomes are as distinctively gendered as were those of their predecessors.

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