Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ARSENIC”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

Distribution of urinary selenium and arsenic among pregnant women exposed to arsenic in drinking water.

Inorganic arsenic (In-As) is a well-known toxicant and carcinogen found naturally in surface and groundwater around the world. Exposure can cause skin lesions, adverse reproductive outcomes, and cancer. There are two main pathways of arsenic (As) metabolism in humans: the reduction reactions, and the oxidative methylation reactions, where methyl groups are attached to As compounds to form monomethylarsenate (MMA) and dimethylarsenate (DMA). MMA, DMA, and In-As are excreted in urine. Urinary levels of another metalloid, selenium (Se), have recently been shown to be associated with increased As excretion and altered metabolite distribution. This study investigates this association, using data collected in a larger prospective study of arsenic and reproductive effects in Chile. This analysis included 93 pregnant women from Antofagasta. Data on demographic, behavioral, and other characteristics were obtained via interviews conducted by trained midwives, and spot urine samples were analyzed for As and Se concentration using inductively coupled plasma-mass spectrometry (ICP-MS). Urinary Se levels were found to be correlated with urinary As levels in bivariate analysis (r = 0.68, P < 0.01). Multiple linear regression analyses revealed that higher urinary Se levels were associated with increased urinary As excretion, increased %DMA, and decreased %In-As. The results of this study suggest that in populations exposed to arsenic, Se intake may be correlated with urinary As excretion, and may alter As methylation.

Adolescent↗

Arsenic and other elements in hair, nails, and skin-scales of arsenic victims in West Bengal, India.

For the first time, biological tissues (hair, nails, and skin-scales) of arsenic victims from an arsenic affected area of West Bengal (WB), India were analyzed for trace elements. Analysis was carried out by inductively coupled plasma-mass spectrometry (ICP-MS) for 10 elements (As, Se, Hg, Zn, Pb, Ni, Cd, Mn, Cu, and Fe). A microwave digester was used for digestion of the tissue samples. To validate the method, certified reference materials--human hair (GBW 07601) and bovine muscle (CRM 8414)--were analyzed for all elements. The W test was used to study the normal/log normal distribution for each element in the tissue samples. For hair (n=44) and nails (n=33), all elements show log-normal distribution. For skin-scale samples (n=11), data are not sufficient to provide the information about the trend. Geometric mean, standard error, and range for each element were presented and compared with literature values for other populations. This study reveals the higher levels of toxic elements As, Mn, Pb, and Ni in the tissue samples compared with available values in the literature. The elevated levels of these toxic metals in the tissues may be due to exposure of these elements through drinking water and food. The correlations of Mn and Ni with other essential elements, e.g. Fe, Cu, Zn, suggest that Mn and Ni may substitute for those elements in hair, nails, and skin-scales. However, correlation represents the relation between two elements only and does not take into consideration of the presence of other elements. Principle component analysis was applied to explain the behavior among the elements present in hair and nails. This study reveals that in the arsenic-affected areas of WB, the concentrations of other toxic elements in drinking water and foodstuff should be monitored to evaluate the arsenic poisoning.

Arsenic↗

Arsenic toxicity and accumulation in turnip as affected by arsenic chemical speciation.

Arsenic (As) uptake by turnip, growing under soilless culture conditions, was studied. A 4 x 3 factorial experiment was conducted with four As species [arsenite, arsenate, methylarsonic acid (MMAA), dimethylarsinic acid (DMAA)] and three As concentrations (1.0, 2.0, and 5.0 mg L(-)(1)). Arsenic phytoavailability and phytotoxicity were primarily determined by As speciation. Organic arsenicals, especially MMAA, were clearly phytotoxic to this turnip cultivar. Plant As concentrations significantly increased with increasing As application rates. Both organic arsenicals showed a higher upward translocation than their inorganic counterparts, contributing to the greater phytotoxicity and lower dry matter productions of these organic treatments. Both inner root and outer root skin As concentrations were above the maximum limit set for As content in food crops (1.0 mg kg(-)(1)). If turnip plants are exposed to a large pulse of As, as growth on contaminated nutrient solutions, they will accumulate residues at levels that are unacceptable for animal and human consumption.

Animals↗

Sulfur-containing arsenical mistaken for dimethylarsinous acid [DMA(III)] and identified as a natural metabolite in urine: major implications for studies on arsenic metabolism and toxicity.

It is vital that methylated trivalent arsenicals [MA(III) and DMA(III)] are described and characterized unequivocally due to their high toxicity. Two different ways of generating the methylated trivalent arsenicals have been practiced-reduction of the methylated pentavalent arsenical either by the sodium-metabisulfite (Na(2)S(2)O(5))/sodium thiosulfate (Na(2)S(2)O(3)) reagent (method A) or by KI, H(2)SO(4), and SO(2) (method B). The shared identity between the products of the two synthetic methods has never been questioned or proven. Here, we characterize and identify the arsenic species formed when reducing DMA(V) by method A or B. Dimethylarsinous acid [DMA(III)] was formed when reducing DMA(V) by method B, but DMA(III) was not the main product of the reaction by method A. The product was revealed by HPLC-ICP-MS coupled simultaneously to HPLC-ES-MS and ES-Q-TOF-MS to have the molecular formula C(2)H(7)OSAs. The structure was further confirmed by (1)H NMR, and ab initio tautomeric energy calculations showed it to be present as Me(2)As(=S)OH (dimethylarsinothioic acid). Dimethylarsinothioic acid was also identified as a metabolite in urine and in wool extract from sheep naturally consuming large amounts of arsenosugars (35 mg of As daily) through their major food source, seaweed.

Animals↗

Outbreak of chronic arsenic poisoning among retired workers from an arsenic mine in Japan.

Retired former workers of Matsuo Arsenic Mine of Miyazaki prefecture in Japan were subjected to extensive medical examination. The number of retired workers subjected to examination were 61 of 208 workers who were engaged in the works of the mine and were tracked down by the work rolls. These workers left the mine more than 15 years prior to the time of the examination. The main works in the mine were classified as mining, dressing of ores, refining, and clerical work. Several findings such as arsenodermatitis, depigmentation, performation of nasal septum, hyposmia, anosmia, and peripheral nervous disturbance attributed to exposure to arsenic were observed in 9 of 21 roasters who often worked in the arsenic kitchen. No characteristic findings of arsenic poisoning, that is, gastrointestinal disturbance, disorder of the cardiovascular system, hematopoietic disorders, or liver disturbance were observed in the retired workers. Another notable finding was that 8 cases diagnosed as pneumoconiosis were found in 18 miners.

Adult↗

Assessing the measurement precision of various arsenic forms and arsenic exposure in the National Human Exposure Assessment Survey (NHEXAS).

Archived samples collected from 1995 to 1997 in the National Human Exposure Assessment Survey (NHEXAS) in U.S. Environmental Protection Agency Region 5 (R5) and the Children's Study (CS) in Minnesota were analyzed for total arsenic, arsenate [As(V)], arsenite, dimethyl arsenic acid (DMA), monomethyl arsenic acid (MMA), arsenobetaine (AsB), and arsenocholine. Samples for the CS included drinking water, urine, hair, and dust; both studies included food (duplicate plate, composited 4-day food samples from participants). Except for AsB and As(V), the levels for As species measured in the food and drinking water samples were very low or nonexistent. The analytical methods used for measuring As species were sensitive to < 1 ppb. During the analysis of food and drinking water samples, chromatographic peaks appeared that contained As, but they did not correspond to those being quantified. Thus, in some samples, the sum of the individual As species levels was less than the total As level measured because the unknown forms of As were not quantified. On the other hand, total As was detectable in almost all samples (> 90%) except for hair (47%), indicating that the analytical method was sufficiently sensitive. Population distributions of As concentrations measured in drinking water, food (duplicate plate), dust, urine, and hair were estimated. Exposures to total As in food for children in the CS were about twice as high as in the general R5 population (medians of 17.5 ppb and 7.72 ppb, respectively). In addition, AsB was the most frequently detected form of As in food eaten by the participants, while As(V) was only rarely detected. Thus, the predominant dietary exposure was from an organic form of As. The major form of As in drinking water was As(V). Spearman (rank) correlations and Pearson (log-concentration scale) correlations between the biomarkers (urine, hair) and the other measures (food, drinking water, dust) and urine versus hair were performed. In the NHEXAS CS, total As and AsB in the food eaten were significantly correlated with their levels in urine. Also, levels of As(V) in drinking water correlated with DMA and MMA in urine. Arsenic levels in dust did not show a relationship with urine or hair levels, and no relationship was observed for food, drinking water, and dust with hair. Urine samples were collected on days 3, 5, and 7 of participants' monitoring periods. Total As levels in urine were significantly associated across the three pairwise combinations--i.e., day 3 versus day 5, day 3 versus day 7, and day 5 versus day 7. Because the half-life of As in the body is approximately 3 days, this suggests that some exposure occurred continually from day to day. This trend was also observed for AsB, suggesting that food is primarily responsible for the continual exposure. DMA and MMA in urine were also significantly correlated but not in all combinations.

Arsenic↗

[Serum and urine total arsenic concentration in a case of acute arsenic intoxication].

The 68-year-old man took arsenic pasta 1 g (arsenic trioxide 0.45 g) to commit suicide and was admitted 16 hours after ingestion. He developed vomiting and coma, followed by pancytopenia. He was treated with activated charcoal, laxative, dimercaprol, sodium thiosulfate and direct hemoperfusion with good recovery. Total arsenic concentrations in serum and urine were 39 ng/ml and 89 ng/ml on admission, respectively. Urine arsenic concentration showed the second peak around 48 hours after admission.

Acute Disease↗

Graphite furnace atomic absorption spectrophotometric determination of 4-hydroxy-3-nitrobenzenearsonic acid, other organic arsenicals, and inorganic arsenic in finished animal feed.

4-Hydroxy-3-nitrobenzenearsonic acid (roxarsone) is administered in animal feed as a growth stimulant over a concentration range of 25-50 ppm. The drug is extracted from 5 g feed with 200 mL aqueous 1.0% ammonium carbonate solution and 5 min of mechanical shaking. Undissolved feed particles are allowed to settle and 1.0 mL aliquot of extract is diluted with 9.0 mL 15% methanol solution. This solution is subjected to sample atomization by a graphite furnace and arsenic detection by atomic absorption spectrophotometry (AAS). Roxarsone recovery from nonmedicated commercial feed fortified at 25 ppm was 103.6% with a relative standard deviation (RSD) of 4.0%. Recovery for 50 ppm fortification was 104.5% (RSD 4.3%). Roxarsone assay results by furnace AAS were compared with results by the current AOAC spectrophotometric method and the AOAC total arsenic method. Results by the 3 methods compare well. The procedure was also used to determine other organic arsenicals and inorganic arsenic in laboratory-fortified feed samples; these recoveries were essentially theoretical.

Animal Feed↗

Oral exposure of dimethylarsinic acid, a main metabolite of inorganic arsenics, in mice leads to an increase in 8-Oxo-2'-deoxyguanosine level, specifically in the target organs for arsenic carcinogenesis.

We have proposed that oral administration of dimethylarsinic acid (DMA), a metabolite of inorganic arsenics in mammals, rather than inorganic arsenics themselves, promotes lung and skin tumors by way of the metabolic production of free radicals such as dimethylarsenic peroxy radical [(CH(3))(2)AsOO*]. The purpose of the present study was to examine if dimethylarsenic has the ability to induce oxidative damage. 8-oxo-2'-deoxyguanosine (8-oxodG) was used as a biomarker of DNA oxidation. The oral administration of DMA enhanced significantly the amounts of 8-oxodG specifically in the target organs (skin, lung, liver, and urinary bladder) of arsenic carcinogenesis and also in urine, whereas arsenite did not. The dimethylarsenics thus may play an important role in arsenic carcinogenesis through the induction of oxidative damage, particularly of base oxidation.

8-Hydroxy-2'-Deoxyguanosine↗

Arsenic extractability in soils in the areas of former arsenic mining and smelting, SW Poland.

Arsenic (As) concentrations in soils and waste material in two areas of former As mining and processing: Złoty Stok (Złote Mts.) and Zeleźniak (Kaczawskie Mts.), SW Poland, were measured to assess levels and environmental risk associated with possible increases in arsenic mobility under changing pH and redox conditions. Twenty six soil samples were collected from 12 sites, and represented a broad spectrum of soil properties and parent material origin, including natural soils, mine spoils, slags and tailings. Arsenic species were examined using a sequential extraction technique. The changes in As solubility were determined from extraction test solutions adjusted to solution pH values varying from 2 to 8. The effects of reducing conditions on As mobility were examined in incubation tests. Most of soils demonstrated extremely high concentrations of As, both of natural and anthropogenic origin. Total As concentrations in all samples were in the range 100-43,500 mg/kg. Sequential extraction techniques suggested that the main species of As in all soils were those bound to iron (Fe) oxides, in particular amorphous ones, whereas the contributions of mobile and specifically sorbed As forms were relatively low. In tailings and tailings-affected alluvial soils, As occurred mainly in residual forms, however these soils also had considerable amounts of mobile As. In all other soils, mobile As forms were very low. Arsenic mobilization could be possible at extremely low or high pH conditions (pH<2 or pH>8), and this may be of particular practical importance in the case of tailings, which are highly alkaline. High pH promotes solubilization of As forms in reducing conditions, whereas in neutral and acidic soils the risk of As release under reducing conditions is limited.

Arsenic↗

Arsenic levels in cooked food and assessment of adult dietary intake of arsenic in the Region Lagunera, Mexico.

The aim of this paper is to estimate the levels of arsenic (As) ingestion through cooked foods consumed in an arsenic endemic area and the assessment of their dietary intake of As. The study was conducted in two villages: a population chronically exposed to a high concentration of As via drinking water (410+/-35 microg/l) and to a low-exposure group (12+/-4 microg/l). A 24-h dietary recall questionnaire was applied to about 25 adult participants in each community. Samples of cooked food, ready for intake, were collected separately from each family's participants. To obtain the As estimate for each food item consumed, the mean quantity of food ingested in grams (wet weight) was calculated and the concentrations of total arsenic (TAs) in each cooked food were determined. The estimations of TAs intake were based on the sum over mean of As ingested from each food item consumed during the 24-h period for each participant. For the estimation of total daily As intake, we summed the mean obtained from food, plain water and hot beverage intakes. The TAs average intakes calculated for low-As-exposure group were 0.94 and 0.76 microg/kg body weight/day, for both summer and winter exposure scenarios, respectively. These values are 44.7 and 36% of the provisional tolerable daily intake (PTDI) for inorganic arsenic (2.14 microg/kg body weight/day), established by the World Health Organization (WHO) in 1989. The WHO reference value was obtained on a weekly basis intake estimation assuming an average body weight of 68 kg in adults. In contrast, for the high-exposure group the TAs average intakes were 16.6 and 12.3 microg/kg body weight/day for summer and winter, respectively. Ingestion via cooked food represented 32.5 and 43.9% of the total daily As intake in the high-exposure group; for summer and winter, respectively. None the less, the bioavailability of As through food can be different than via drinking water.

Adult↗

On-column formation of arsenic-glutathione species detected by size-exclusion chromatography in conjunction with arsenic-specific detectors.

The 'retention analysis method', which is based on size-exclusion chromatography (SEC) in conjunction with an arsenic-specific detector (graphite furnace atomic absorption spectrometer, GFAAS), was used to study the effect of pH (range 2.0-10.0), temperature (4, 25 and 37 degrees C), and the concentration of glutathione in the mobile phase (0.5-7.5 mM) on the formation of arsenic-glutathione species after injection of sodium arsenite using phosphate-buffered saline solutions as mobile phases. The formation of arsenic-GSH species was facilitated by low temperatures (4 degrees C), pH 6.0-8.0 and high concentrations of glutathione (7.5 mM) in the mobile phase. Simulating the physicochemical parameters found inside human red blood cells (approximately 3.0 mM glutathione, 37 degrees C, pH 7.4) and hepatocytes (approximately 7.5 mM glutathione, 37 degrees C, pH 7.4), SEC-GFAAS provided evidence for the formation of arsenic-glutathione species under these conditions. In addition, the 'chelating agent', sodium DL-2,3-dimercapto- -propanesulfonate (1.0 and 2.0 mM) was demonstrated to bind arsenous acid stronger in the presence of glutathione (7.5 mM) under these conditions (PBS buffer, pH 7.4, 37 degrees C).

Arsenic↗

Diastereoisomers of an 'arsenomethionine'-based structure from Sargassum lacerifolium: the formation of the arsenic-carbon bond in arsenic-containing natural products.

Separation and 1H NMR spectra of a pair of arsenic-containing diastereoisomers (1a and 1b) isolated from a brown alga has provided support for their structures (proposed on the basis of NMR spectra of the unseparated mixture). The diastereoisomerism and analogies with nitrogen-containing algal lipids indicated that they were derived from an analogue of methionine in which the dimethylarsinoyl- group had replaced amino. Although S-adenosylmethionine is probably the source of methyl and 5'-deoxyribose-5'-yl groups in arsenic-containing natural products, the arsenic-carbon bonds in some compounds might be formed by a process in which arsenic replaces nitrogen in amino-acid synthesis.

Animals↗

Heavy metal, total arsenic, and inorganic arsenic contents of algae food products.

The total arsenic, inorganic arsenic, lead, cadmium, and mercury contents of 18 algae food products currently on sale in Spain were determined. The suitability of the analytical methodologies for this type of matrix was confirmed by evaluating their analytical characteristics. The concentration ranges found for each contaminant, expressed in milligrams per kilogram of dry weight, were as follows: total arsenic, 2.3-141; inorganic arsenic, 0.15-88; lead, < 0.05-1.33; cadmium, 0.03-1.9; and mercury, 0.004-0.04. There is currently no legislation in Spain regarding contaminants in algae food products, but some of the samples analyzed revealed Cd and inorganic As levels higher than those permitted by legislation in other countries. Given the high concentrations of inorganic As found in Hizikia fusiforme, a daily consumption of 1.7 g of the product would reach the Provisional Tolerable Weekly Intake recommended by the WHO for an average body weight of 68 kg. A more comprehensive study of the contents and toxicological implications of the inorganic As present in the algae food products currently sold in Spain may be necessary, which might then be the basis for the introduction of specific sales restrictions.

Arsenic↗

An arsenic metallochaperone for an arsenic detoxification pump.

Environmental arsenic is a world-wide health issue, making it imperative for us to understand mechanisms of metalloid uptake and detoxification. The predominant intracellular form is the highly mephitic arsenite, which is detoxified by removal from cytosol. What prevents arsenite toxicity as it diffuses through cytosol to efflux systems? Although intracellular copper is regulated by metallochaperones, no chaperones involved in conferring resistance to other metals have been identified. In this article, we report identification of an arsenic chaperone, ArsD, encoded by the arsRDABC operon of Escherichia coli. ArsD transfers trivalent metalloids to ArsA, the catalytic subunit of an As(III)/Sb(III) efflux pump. Interaction with ArsD increases the affinity of ArsA for arsenite, thus increasing its ATPase activity at lower concentrations of arsenite and enhancing the rate of arsenite extrusion. Cells are consequently resistant to environmental concentrations of arsenic. This report of an arsenic chaperone suggests that cells regulate the intracellular concentration of arsenite to prevent toxicity.

Arsenic↗

Effects of arsenic species and concentrations on arsenic accumulation by different fern species in a hydroponic system.

Two hydroponic experiments were conducted to evaluate factors affecting plant arsenic (As) hyperaccumulation. In the first experiment; two As hyperaccumulators (Pteris vittata and P. cretica mayii) were exposed to 1 and 10 mg L(-1) arsenite (AsIII) and monomethyl arsenic acid (MMA) for 4 wk. Total As concentrations in plants (fronds and roots) and solution were determined In the second experiment P. vittata and Nephrolepis exaltata (a non-As hyperaccumulator) were exposed to 5 mgL(-1) arsenate (AsV) and 20 mgL(-1) AsIIIfor 1 and 15 d. Total As and AsIII concentrations in plants were determined Compared to P. cretica mayii, P. vittata was more efficient in arsenic accumulation (1075-1666 vs. 249-627mg kg(-1) As in the fronds) partially because it is more efficient in As translocation. As translocation factor (As concentration ratio in fronds to roots) was 3.0-5.6 for P. vittata compared to 0.1 to 4.8 for P. cretica. Compared to N. exaltata, P. vittata was significantly more efficient in arsenic accumulation (38-542 vs. 4.8-71 mg kg(-1) As in thefronds) as well asAs translocation (1.3-5.6 vs. 0.2-0.5). In addition, P. vittata was much more efficient in As reduction from AsV to AsIII (83-84 vs. 13-24% AsIII in the fronds). Little As reduction occurred after 1-d exposure to AsV in both species indicates that As reduction was not instantaneous even in an As hyperaccumulator. Our data were consistent with the hypothesis that both As translocation and As reduction are important for plant As hyperaccumulation.

Arsenates↗

Neuropathy in arsenic toxicity from groundwater arsenic contamination in West Bengal, India.

Large number of people from 9 out of 18 districts of West Bengal, India are endemically exposed to arsenic contaminated groundwater due to drinking of tubewell water containing arsenic level above World Health Organization's maximum permissible limit of 50 microg/L. From our ongoing studies on neurological involvement in patients of arsenicosis from different districts of West Bengal, we report our findings in a total of 451 patients of three districts (Murshidabad, Nadia, and Burdwan), comprising 267 males and 184 females with age ranging from 11 to 79 years. They all had arsenical skin lesions, positive biomarkers and identified source of arsenic contaminated water drinking. Peripheral neuropathy was the predominant neurological complication in these patients affecting 154 (37.3%) of 413 patients of Group 1 and 33 (86.8%) of 38 patients of Group 2. Other possible causes and alternative explanations of neuropathy were excluded. The temporal profile in most of the cases (154 of Group 1) were of chronic affection while the 33 patients of Group 2 developed both neuropathy and dermopathy subacutely. Subacutely affected Group 2 patients had much higher incidence of neuropathy. Paresthesias and pains in the distal parts of extremities were much higher in incidence in Group 2 (73.7% and 23.7% respectively) than in Group 1 (18.4% and 11.1%). Distal limb weakness or atrophy was evident in 7.3% in Group 1 and 10.5% in Group 2. Overall, sensory features were more common than motor features in patients of neuropathy and sensory neuropathy was diagnosed in 30% and 76.3% and sensorimotor in 7.3% and 10.5% respectively in Group 1 and Group 2 subjects. Nerve conduction and electromyographic studies performed in 88 cases revealed dysfunction of sensory nerve in 45% and 27% and of motor nerve in 20% and 16.7% of patients with moderate degree and mild degree of clinical neuropathies respectively. Evoked potential studies performed in 20 patients were largely normal except for two instances each of abnormal visual evoked potential and brainstem auditory evoked potential findings. Prognosis was favorable in mild and early diagnosed cases of neuropathy whereas most of the other more severe and late diagnosed cases showed slow and partial recovery or even deterioration. Outcome in neuropathic patients of arsenicosis and long term toxic neurologic effects yet unexplored and unknown remain as matters of future concern requiring close monitoring.

Adolescent↗

Arsenic-copper interaction in the kidney of the rat: influence of arsenic metabolites.

The present study was an attempt to investigate whether the renal accumulation of Cu observed in the kidneys of rats and guinea-pigs exposed to arsenite (As-III) was an effect of arsenite alone or also shared by its metabolites--arsenate (As-V), dimethylarsinic acid and monomethylarsonic acid. The four arsenic compounds were administered subcutaneously and separately to rats for 12 days in increasing doses. Kidney, liver and blood were taken and analysed for As, Cu and other trace elements by atomic emission spectrometry. Results indicate that administration of As-V leads to renal Cu accumulation similar to that observed on administration of As-III and that the accumulation in both cases is dependent on the dose of arsenic, although higher doses of As-V were required to achieve renal Cu levels comparable to that of As-III. A constant molar As:Cu ratio independent of arsenic dose was obtained in the kidney. Dimethylarsinic acid did not affect renal Cu levels at all. Administration of monomethylarsonic acid led to a slight increase in renal Cu levels which did not increase further in spite of increased doses of monomethylarsonic acid. It is concluded from these studies that neither the metabolic transformation of inorganic arsenic to its methylated products nor its metabolites (dimethylarsinic acid and monomethylarsonic acid) caused the observed renal Cu accumulation, rather, the inorganic form of As, either in the trivalent or pentavalent form is responsible.

Animals↗