Arsenic is not stored as arsenite - phytochelatin complexes in the seaweeds Fucus spiralis and Hizikia fusiforme

2011 ◽  
Vol 8 (1) ◽  
pp. 30 ◽  
Author(s):  
B. Alan Wood ◽  
Shinichi Miyashita ◽  
Toshikazu Kaise ◽  
Andrea Raab ◽  
Andrew A. Meharg ◽  
...  
Keyword(s):  
Arsenic Concentration ◽  
Arsenic Exposure ◽  
Toxic Metal ◽  
Inorganic Arsenic ◽  
Terrestrial Plants ◽  
Generic Structure ◽  
Edible Seaweed ◽  
Hizikia Fusiforme ◽  
Toxic Metalloid ◽  
Fucus Spiralis

Environmental context Seaweeds hyperaccumulate the toxic metalloid arsenic, but seemingly achieve detoxification by transformation to arsenosugars. The edible seaweed hijiki is a notable exception because it contains high levels of toxic arsenate and arsenite. Terrestrial plants detoxify arsenic by forming arsenite–phytochelatin complexes. The hypothesis that seaweeds also synthesise phytochelatins to bind arsenite as a means of detoxification before arsenosugar synthesis is tested in this investigation. Abstract Phytochelatins (PCs), generic structure [γ-Glu-Cys]n-Gly, are peptides synthesised by terrestrial plants to bind toxic metal(loid)s such as cadmium and arsenic. Seaweeds are arsenic hyperaccumulators, seemingly achieving detoxification via arsenosugar biosynthesis. Whether seaweeds synthesise PCs to aid detoxification during arsenic exposure is unknown. Hizikia fusiforme (hijiki) and Fucus spiralis were used as model seaweeds: the former is known for its large inorganic arsenic concentration, whereas the latter contains mainly arsenosugars. F. spiralis was exposed to 0, 1 and 10 mg L–1 arsenate solutions for 24 h, whereas hijiki was analysed fresh. All samples contained AsIII, glutathione and reduced PC2, identified using HPLC-ICP-MS/ES-MS. Although hijiki contained no AsIII–PC complexes, arsenate exposed F. spiralis generated traces of numerous arsenic compounds that might be AsIII–GS or AsIII–PC2 complexes. AsIII–PC complexes seem not to be a principal storage form for long-term arsenic storage within seaweeds. However, 40 times higher glutathione concentrations were found in hijiki than F. spiralis, which may explain how hijiki deals with its high inorganic arsenic burden.

scholarly journals Variation in Arsenic metabolism in schistosomiasis associated bladder pathology in a rural community, Eggua, Ogun State, Nigeria

2021 ◽  
Vol 25 (9) ◽  
pp. 1645-1652
Author(s):  
A.T. Adeboye ◽  
H.O. Awobode ◽  
A.S. Adebayo ◽  
J.R. Djouaka ◽  
R.D. Isokpehi ◽  
...  
Keyword(s):  
Arsenic Concentration ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Urogenital Schistosomiasis ◽  
Arsenic Metabolism ◽  
Ogun State ◽  
Specific Pcr ◽  
Urinary Arsenic ◽  
Increased Risk ◽  
Bladder Pathology

Exposure to toxic inorganic Arsenic (iAs) in areas endemic for urogenital schistosomiasis may confer increased risk for bladder cancer. The severity of the adverse effects of iAs however depends on its metabolism, which is highly variable among individuals. Genetic polymorphism in Arsenic (+3) Methyl Transferase enzyme, accounts significantly for these variations. To investigate the relationship of AS3MT gene polymorphisms and Arsenic metabolism to schistosomiasis and/or associated bladder pathology, 119 individualsfrom Eggua in southwest Nigeria were recruited for this study. Screening for schistosomiasis and bladder pathology was done by microscopy and ultrasonography respectively. Wagtech Digital Arsenator was used to assess total urinary arsenic concentrations and thus determine the level of arsenic exposure. The single nucleotide polymorphism AS3MT/Met287Thr T>C (rs11191439) was genotyped using Alelle-Specific PCR. Of the participants who tested positive for schistosomiasis, 33.3% exhibited bladder pathology. Total urinary arsenic concentration in 80% of the participants was above the WHO limit of 0.05mg/L. The Met287Thr allelic distribution conformed to the Hardy-Weinberg equilibrium (X2= 0.161, P> 0.05). Observed allelic frequencies were 0.96 and 0.04 for wild-type T and mutant C alleles respectively. There was no significant relationship between AS3MT SNP, arsenic concentrations and schistosomiasis associated bladder pathology. In conclusion, the community is highly exposed to arsenic, although with a possible genetic advantage of increased AS3MT catalytic activity. However, we see the need for urgent intervention as inter-individual differences in arsenic metabolism may influence the bladder pathology status of individuals in the community. And although urogenital schistosomiasis is waning in Eggua, it is not known what synergy the infection and high arsenic exposure may wield on bladder pathology.

Abstract P064: Inverse Associations Between Inorganic Arsenic and Obesity: Findings From the National Health and Nutrition Examination Survey

Circulation ◽  
2016 ◽  
Vol 133 (suppl_1) ◽  
Author(s):  
Catherine Bulka ◽  
Sithembile Mabila ◽  
Mary Turyk ◽  
Maria Argos
Keyword(s):  
Waist Circumference ◽  
National Health ◽  
Arsenic Concentration ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
The United States ◽  
Serum Folate ◽  
Hydration Status ◽  
Nutrition Examination Survey ◽  
Health And Nutrition

Introduction: Arsenic is ubiquitous in the environment as an element of the earth’s crust. Human exposure predominantly occurs through ingestion of contaminated drinking water and arsenic-rich foods such as seafood and rice. Chronic exposure to inorganic arsenic has been associated with certain cancers, and more recently with cardiovascular disease and diabetes that are common among the obese. However, little is known about the specific relationship between inorganic arsenic exposure and obesity. Hypothesis: We assessed the hypothesis that inorganic arsenic exposure was correlated with obesity in the general population of the United States. Methods: We analyzed a representative sample of 4,105 adults from the U.S. population using data from the 2007-2010 National Health and Nutrition Examination Survey (NHANES). Arsenobetaine and arsenocholine concentrations, which are forms of organic arsenic, were subtracted from total urinary arsenic concentrations to estimate the amount of inorganic arsenic in urine as a biomarker of exposure. These values were standardized by urinary creatinine to control for hydration status. Obesity was assessed using measured body mass index (BMI) in kg/m 2 and waist circumference in cm. Crude and adjusted survey-weighted linear regression models were performed. Results: Creatinine-adjusted urinary inorganic arsenic concentrations were inversely associated with log-transformed BMI (p for trend = 0.0003) and log-transformed waist circumference (p for trend = 0.0001). The highest quintile of inorganic arsenic concentration (>10.4 to 483.3 μg/L) was associated with a 5% (95% CI: 3 to 8%) lower BMI and a 4% (95% CI: 2 to 6%) smaller waist circumference compared to the lowest quintile (0 to 2.3 μg/L). Adjustments for age, gender, race, thyroid problems, diabetes, smoking status, seafood consumption, rice consumption, red blood cell folate, serum folate, socioeconomic status, and survey cycle did not appreciably alter these results. There was no evidence of effect modification between urinary inorganic arsenic concentrations and covariates on obesity. Conclusions: While inorganic arsenic exposure has generally been positively associated with obesity-related diseases, we observed a negative association between urinary inorganic arsenic concentrations and obesity in this representative cross-sectional analysis. It is unclear if this is a true association in which inorganic arsenic exposure is protective against obesity, or if this finding reflects differential arsenic absorption, metabolism, or storage by adiposity level.

Effects of low-level arsenic exposure on urinary N-acetyl-β-D-glucosaminidase activity

2011 ◽  
Vol 30 (12) ◽  
pp. 1885-1891 ◽  
Author(s):  
S-Y Eom ◽  
Y-C Lee ◽  
D-H Yim ◽  
C-H Lee ◽  
Y-D Kim ◽  
...  
Keyword(s):  
Arsenic Concentration ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Tubular Damage ◽  
Seafood Consumption ◽  
Arsenic Level ◽  
Urine Sampling ◽  
Low Level ◽  
Urinary Arsenic ◽  
Renal Tubular

This study was aimed to evaluate whether renal tubular function is impaired by exposure to relatively low concentrations of arsenic. Mean urinary arsenic concentrations and N-acetyl-β-d-glucosaminidase (NAG) activities were compared among 365 and 502 Korean men and women, respectively, in relation to gender, smoking, alcohol consumption, and recent seafood consumption. The study subjects were divided into 4 groups according to urinary NAG activity and seafood consumption prior to urine sampling, and the correlation between arsenic concentration and urinary NAG activity was tested for each group. The mean urinary arsenic level was higher in women, non-smokers, and non-drinkers in comparison to men, smokers, and drinkers, respectively. Individuals who consumed seafood within 3 days prior to urine sampling showed a higher mean urinary arsenic level than those who did not. The correlation between urinary arsenic concentration and NAG activity in urine was significant only in subjects who did not consume seafood within 3 days prior to urine sampling and whose urinary NAG activity was 7.44 U/g creatinine (75th percentile) or higher. The urinary arsenic concentration was a significant determinant of urinary NAG activity in subjects with NAG activity higher than 7.44 U/g creatinine and especially in those who had not consumed seafood recently. These facts suggest that a relatively low-level exposure to inorganic arsenic produces renal tubular damage in humans.

scholarly journals Groundwater Irrigation and Arsenic Speciation in Rice in Cambodia

2018 ◽  
Vol 8 (19) ◽  
Author(s):  
Tom Murphy ◽  
Kongkea Phan ◽  
Emmanuel Yumvihoze ◽  
Kim Irvine ◽  
Ken Wilson ◽  
...  
Keyword(s):  
Arsenic Speciation ◽  
Arsenic Concentration ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Arsenic Species ◽  
Dimethylarsinic Acid ◽  
Total Arsenic ◽  
Groundwater Irrigation ◽  
Financial Interests ◽  
Rice Consumption

Background. Arsenic bioaccumulation in rice is a global concern affecting food security and public health. Objective. The present study examined arsenic species in rice in Cambodia to characterize health risks with rice consumption and to clarify uncertainties with Codex guidelines. Methods. The present study collected 61 well water samples, 105 rice samples, 70 soil samples, and conducted interviews with 44 families in Preak Russey near the Bassac River and Kandal Province along the Mekong River in Cambodia. Analyses of metals, total arsenic and arsenic species were conducted in laboratories in Canada, Cambodia and Singapore. Results. Unlike in Bangladesh, rice with the highest total arsenic concentrations in Cambodia contains mostly organic arsenic, dimethylarsinic acid (DMA), which is unregulated and much less toxic than inorganic arsenic. The present study found that storing surface runoff in ditches prior to irrigation can significantly reduce the arsenic concentration in rice. It is possible to remove > 95% of arsenic from groundwater prior to irrigation with natural reactions. Conclusions. The provision of high quality drinking water in 2015 to Preak Russey removed about 95% of the dietary inorganic arsenic exposure. The extremes in arsenic toxicity that are still obvious in these farmers should become less common. Rice from the site with the highest documented levels of arsenic in soils and water in Cambodia passes current Codex guidelines for arsenic. Informed Consent. Obtained Competing Interests. The authors declare no competing financial interests.

scholarly journals Biotic and Abiotic Factors Influencing Arsenic Biogeochemistry and Toxicity in Fluvial Ecosystems: A Review

2020 ◽  
Vol 17 (7) ◽  
pp. 2331
Author(s):  
Laura Barral-Fraga ◽  
María Teresa Barral ◽  
Keeley L. MacNeill ◽  
Diego Martiñá-Prieto ◽  
Soizic Morin ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Future Research ◽  
Strong Impact ◽  
Trophic Relations ◽  
Fluvial Systems ◽  
Pampean Streams ◽  
Micro Organisms ◽  
Different Origins

This review is focused on the biogeochemistry of arsenic in freshwaters and, especially, on the key role that benthic microalgae and prokaryotic communities from biofilms play together in through speciation, distribution, and cycling. These microorganisms incorporate the dominant iAs (inorganic arsenic) form and may transform it to other arsenic forms through metabolic or detoxifying processes. These transformations have a big impact on the environmental behavior of arsenic because different chemical forms exhibit differences in mobility and toxicity. Moreover, exposure to toxicants may alter the physiology and structure of biofilms, leading to changes in ecosystem function and trophic relations. In this review we also explain how microorganisms (i.e., biofilms) can influence the effects of arsenic exposure on other key constituents of aquatic ecosystems such as fish. At the end, we present two real cases of fluvial systems with different origins of arsenic exposure (natural vs. anthropogenic) that have improved our comprehension of arsenic biogeochemistry and toxicity in freshwaters, the Pampean streams (Argentina) and the Anllóns River (Galicia, Spain). We finish with a briefly discussion of what we consider as future research needs on this topic. This work especially contributes to the general understanding of biofilms influencing arsenic biogeochemistry and highlights the strong impact of nutrient availability on arsenic toxicity for freshwater (micro) organisms.

Inorganic arsenic exposure affects pain behavior and inflammatory response in rat

2008 ◽  
Vol 229 (3) ◽  
pp. 374-385 ◽  
Author(s):  
P AGUIRREBANUELOS ◽  
C ESCUDEROLOURDES ◽  
L SANCHEZPENA ◽  
L DELRAZO ◽  
J PEREZURIZAR
Keyword(s):  
Inflammatory Response ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Pain Behavior

scholarly journals A risk–benefit analysis approach to seafood intake to determine optimal consumption

2011 ◽  
Vol 107 (12) ◽  
pp. 1812-1822 ◽  
Author(s):  
Véronique Sirot ◽  
Jean-Charles Leblanc ◽  
Irène Margaritis
Keyword(s):  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Hierarchical Cluster ◽  
Good Health ◽  
Benefit Analysis ◽  
Food Contaminants ◽  
Public Health Perspective ◽  
Contaminant Exposure ◽  
Consumption Level ◽  
Risk Benefit Analysis

Seafood provides n-3 long-chain PUFA (n-3 LC-PUFA), vitamins and minerals, which are essential to maintain good health. Moreover, seafood is a source of contaminants such as methylmercury, arsenic and persistent organic pollutants that may affect health. The aim of the present study was to determine in what quantities seafood consumption would provide nutritional benefits, while minimising the risks linked to food contaminants. Seafood was grouped into clusters using a hierarchical cluster analysis. Those nutrients and contaminants were selected for which it is known that seafood is a major source. The risk–benefit analysis consisted in using an optimisation model with constraints to calculate optimum seafood cluster consumption levels. The goal was to optimise nutrient intakes as well as to limit contaminant exposure with the condition being to attain recommended nutritional intakes without exceeding tolerable upper intakes for contaminants and nutrients, while taking into account background intakes. An optimum consumption level was calculated for adults that minimises inorganic arsenic exposure and increases vitamin D intake in the general population. This consumption level guarantees that the consumer reaches the recommended intake for n-3 LC-PUFA, Se and I, while remaining below the tolerable upper intakes for methylmercury, Cd, dioxins, polychlorobiphenyls, Zn, Ca and Cu. This consumption level, which is approximately 200 g/week of certain fatty fish species and approximately 50 g/week of lean fish, molluscs and crustaceans, has to be considered in order to determine food consumption recommendations in a public health perspective.

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