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Inorganic arsenic (iAs) is carcinogenic to humans. Methylated metabolites of arsenic (As) found in the urine could serve as potential tools for screening and early detection of cancer in populations exposed to As. Relatively little information is available regarding changes in As methylation profiles after cessation of As exposure.
We examined the...
Contexts in source publication
Context 1
... chronic arsenic exposure increases the risk of cancer ( Chen et al. 1985Chen et al. , 1992Wu et al. 1989), it is logical that the cancerfree participants had lower cumulative exposure to arsenic in the past. Table 2 presents intraindividual differ ences in As methylation indices of residents in 1989 and 2004. Generally speaking, sam ples collected in 2004 had lower %iAs and %MMA V but higher %DMA V and SMI than did the urine samples collected in 1989. ...
Context 2
... the present study, we found the sub cohort of cancerfree residents to be more effi cient in methylating As (Table 2). One possible reason was demonstrated in an animal study by Kenyon et al. (2008), who found that mice preferentially accumulate MMA in the kid ney after subchronic exposure to As V in drink ing water. ...
Similar publications
Arsenic is categorized by the WHO as the most significant environmental contaminant of drinking water due to the prevalence of geogenic contamination of groundwaters. Arsenic and the compounds which it forms are considered to be carcinogenic. The mechanism of toxicity and in particular of carcinogenicity of arsenic is still not well understood. The...
Citations
... 44 Figure 3 shows mean iAs%, MMA%, and DMA% in urine reported for populations in Bangladesh, 15 USA, 14 South Korea, 89 and Taiwan, China. 90 The amounts of fish and seafood consumption per capita is lower in the United States (22 kg per capita per year in 2020) and Bangladesh (26 kg) than in China (40 kg) and South Korea (54 kg) (https:// Environment & Health pubs.acs.org/EnvHealth Perspective ourworldindata.org/grapher/fish-and-seafood-consumptionper-capita). ...
... 52 14 Bangladesh, 15 South Korea, 89 and Taiwan, China. 90 The numbers on top of each bar are mean percentages of the corresponding arsenic species. ...
Extensive research has used dimethylarsinic acid (DMA) in urine as a marker of arsenic methylation. The premise is that humans methylate inorganic arsenicals to monomethylarsonic acid (MMA) and DMA and excrete these arsenic species into the urine. However, DMA in urine not only comes from the methylation of inorganic arsenic but also could be a result of metabolism of other arsenic species, such as arsenosugars and arsenolipids. Most environmental health and epidemiological studies of arsenic methylation might have overlooked confounding factors that contribute to DMA in urine. Here we critically evaluate reported studies that used methylation indexes, concentration ratios of methylated arsenicals, or the percentage of DMA in urine as markers of arsenic methylation efficiency. Dietary intake of arsenosugars potentially confounds the calculation and interpretation of the arsenic methylation efficiencies. Many studies have not considered incidental dietary intake of arsenosugars, arsenolipids, and other organic arsenic species. Future studies should consider the dietary intake of diverse arsenic species and their potential effect on the urinary concentrations of DMA.
... Although total urinary As was used to determine iAs exposure in many studies, it is important to distinguish between iAs and its metabolites and its organic forms. Herewith, to estimate absorbed iAs levels in individuals living in the study region, besides total urinary As measurements, As species [As(III), As(V), DMA and MMA] levels were also used, allowing for better estimation of recently absorbed As (Huang et al., 2009;WHO, 2001). ...
... The metabolite ratios of As (MMA/iAs and DMA/MMA) are widely used markers for estimation of the individual methylation capacity (Del Razo et al., 2011;Huang et al., 2009;McCarty et al., 2007;Normandin et al., 2014;Xu et al., 2008). In our study, urinary iAs% and DMA% were within ranges reported for other populations Heck et al., 2007;Hopenhayn-Rich et al., 1996;Hsu et al., 2017;Huang et al., 2008;Lindberg et al., 2008;Yu et al., 2000). ...
... Thus, it was proposed that several factors (e.g. folic acid, cysteine, methionine, niacin, choline, S-adenosyl methionin, and vitamin B 12 ), affecting the single-carbon metabolism, can alter the As metabolism and that they may have an influence on the human health (Gamble et al., 2005;Heck et al., 2007;Huang et al., 2009). It is well known that folate is an important co-factor involved in transportation and use of the methyl groups during single-carbon metabolism; folate deficiency has become increasingly important in many diseases (Choi and Mason, 2000;Stanger, 2002). ...
Background
There is no human data regarding the exposure, metabolism and potential health effects of arsenic (As) contamination in drinking water in the Central Anatolian region, Turkey.
Methods
Residents in the 10 villages with drinking water total As (T-As) level >50 μg/L and 10–50 μg/L were selected as an exposed group (n = 420) and, <10 μg/L as an unexposed group (n = 185). Time-weighted average-As (TWA-As) intakes were calculated from T-As analysis of drinking water samples (DWS). Concentrations of T-As in urine and hair samples, urinary As species (i.e., As (III), As (V), MMA-V and DMA-V), and some micronutrients in serum samples of residents were analyzed. Primary and secondary methylation indices (PMI, SMI; respectively) were assessed from urinary As species concentrations and the presence of skin lesion was examined.
Results
TWA-As intake was 75 μg/L in exposed group. Urinary and hair T-As and urinary As species concentrations were significantly higher in exposed group (p < 0.05). PMI and SMI values revealed that methylation capacities of the residents were efficient and that there was no saturation in As metabolism. No significant increase was observed in the frequency of skin lesions (hyperpigmentation, hypopigmentation, keratosis) of exposed group (p > 0.05). Only frequency of keratosis either at hand or foot was higher in individuals with hair As concentration >1 μg/g (p < 0.05).
Conclusion
Individuals living in the study area were chronically exposed to low-to-moderate As due to geological contamination in drinking water. No significant increase was observed in the frequency of skin lesions. It is important to begin long-term follow-up studies about health effects in this region due to controversial results about health risks of low-to moderate As exposure.
... Although total urinary As was used to determine iAs exposure in many studies, it is important to distinguish between iAs and its metabolites and its organic forms. Herewith, to estimate absorbed iAs levels in individuals living in the study region, besides total urinary As measurements, As species [As(III), As(V), DMA and MMA] levels were also used, allowing for better estimation of recently absorbed As (Huang et al., 2009;WHO, 2001). ...
... The metabolite ratios of As (MMA/iAs and DMA/MMA) are widely used markers for estimation of the individual methylation capacity (Del Razo et al., 2011;Huang et al., 2009;McCarty et al., 2007;Normandin et al., 2014;Xu et al., 2008). In our study, urinary iAs% and DMA% were within ranges reported for other populations Heck et al., 2007;Hopenhayn-Rich et al., 1996;Hsu et al., 2017;Huang et al., 2008;Lindberg et al., 2008;Yu et al., 2000). ...
... Thus, it was proposed that several factors (e.g. folic acid, cysteine, methionine, niacin, choline, S-adenosyl methionin, and vitamin B 12 ), affecting the single-carbon metabolism, can alter the As metabolism and that they may have an influence on the human health (Gamble et al., 2005;Heck et al., 2007;Huang et al., 2009). It is well known that folate is an important co-factor involved in transportation and use of the methyl groups during single-carbon metabolism; folate deficiency has become increasingly important in many diseases (Choi and Mason, 2000;Stanger, 2002). ...
... Из окислительных форм неорганического мышьяка трехвалентный арсенит (AsIII) обладает наиболее выраженным токсическим воздействием на организм человека [79]. При попадании в кератиноциты неорганический мышьяк вступает в реакцию внутриклеточного метилирования и преобразуется в менее токсичные метаболиты [80]. Для этого процесса необходимо участие основных клеточных органелл -ядра и митохондрий, в которых в результате данного взаимодействия возникают различные структурные аномалии, составляющие основу онкогенеза болезни Боуэна. ...
This review article provides an overview of the etiology, pathogenesis, clinical presentation, diagnosis, and treatment methods for actinic keratosis, keratoacanthoma, and Bowen’s disease. The provoking factors are described, where the main importance is attached to insolation, previous immunosuppression and immunodeficiency and trauma. The pathogenesis of these diseases is described in the form of cascade models. Various clinical forms and their main dermatoscopic features, suitable for digital processing in automated diagnostic systems, are presented. A stepwise approach to the treatment of these nosologies is described, and a preliminary prognosis is assessed based on the duration of progression and the likelihood of transformation into squamous cell carcinoma. Given the fact that dermato-oncologists have not yet come to a consensus on the classification of the described diseases, in this article they are considered as a borderline, thereby demonstrating a fine line of transition from a precancerous state to cancer in situ.
... Wei et al. [21] concluded that the arsenic methylation efficiency was significantly lower due to chronic exposure to high levels of arsenic in the environment. But Huang et al. [22] performed arsenic speciation for non-tumor residents in southern Taiwan with a 15-year interval after cessation of arsenic ingestion, and demonstrated an increase of methylation. In our study, the decreased capacity of methylation metabolism in patients seemed to continue even after 10 years off ATO. ...
Background
Arsenic trioxide [ATO, inorganic arsenite (iAs III ) in solution] plays an important role in the treatment of acute promyelocytic leukemia (APL). However, the long-term adverse effects (AEs) and the retention of arsenic among APL patients are rarely reported. In this study, we focused on arsenic methylation metabolism and its relationship with chronic hepatic toxicity, as we previously reported, among APL patients who had finished the treatment of ATO.
Methods
A total of 112 de novo APL patients who had completed the ATO-containing treatment were enrolled in the study. Arsenic species [iAs III , inorganic arsenate (iAs V ), and their organic metabolites, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)] in patients’ plasma, urine, hair and nails were detected by high-performance liquid chromatography combined with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Eighteen single nucleotide polymorphisms (SNPs) of the arsenic (+ 3 oxidative state) methylation transferase ( AS3MT ) gene, which was known as the main catalyzer for arsenic methylation, were tested with the polymerase chain reaction method.
Results
The study showed the metabolic pattern of arsenic in APL patients undergoing and after the treatment of ATO, in terms of total arsenic (TAs) and four species of arsenic. TAs decreased to normal after 6 months since cessation of ATO. But the arsenic speciation demonstrated significantly higher portion of iAs III in patient’s urine (40.08% vs. 1.94%, P < 0.001), hair (29.25% vs. 13.29%, P = 0.002) and nails (30.21% vs. 13.64%, P = 0.003) than the healthy controls’, indicating a decreased capacity of arsenic methylation metabolism after the treatment of ATO. Urine primary methylation index (PMI) was significantly lower in patients with both chronic liver dysfunction (0.14 vs. 0.28, P = 0.047) and hepatic steatosis (0.19 vs. 0.3, P = 0.027), suggesting that insufficient methylation of arsenic might be related to chronic liver disorders. Two SNPs (A9749G and A27215G) of the AS3MT gene were associated with impaired urine secondary methylation index (SMI).
Conclusions
The long-term follow-up of arsenic speciation indicated a decreased arsenic methylation metabolism and a probable relationship with chronic hepatic disorders among APL patients after the cessation of ATO. Urine PMI could be a monitoring index for chronic AEs of ATO, and the SNPs of AS3MT gene should be considered when determining the dosage of ATO.
... In particular, some seafood contains organic As in form of arsenobetaine (less toxic), which is rapidly excreted via urine after recent sh consumption; thus, misleadingly showing high iAs. The speciation methods can distinguish iAs, MMA and DMA from remaining As compounds and it is thought that urinary As metabolites are better predictors for As toxicity when compared to total As (ATSDR 2007;Huang et al. 2009). Herewith, to estimate absorbed iAs doses in the individuals living in study region, besides total urinary As measurements As species (AsIII, AsV, DMA and MMA) levels are also used which is allowing better quantitative estimation for recently absorbed As (Huang et al. 2009;WHO 2001). ...
... The speciation methods can distinguish iAs, MMA and DMA from remaining As compounds and it is thought that urinary As metabolites are better predictors for As toxicity when compared to total As (ATSDR 2007;Huang et al. 2009). Herewith, to estimate absorbed iAs doses in the individuals living in study region, besides total urinary As measurements As species (AsIII, AsV, DMA and MMA) levels are also used which is allowing better quantitative estimation for recently absorbed As (Huang et al. 2009;WHO 2001). ...
... The metabolite ratios (MMA: iAs and DMA: MMA) are widely used markers for estimation of individual methylation capacity. Similar indices are used in the epidemiological studies from several countries (Del Razo et al. 2011;Huang et al. 2009;McCarty et al. 2007;Normandin et al. 2014;Xu et al. 2008). ...
Background: There is no human data regarding exposure, metabolism and potential health effects of arsenic (As) contamination in drinking water in the Central Anatolian region, Turkey.
Methods: Residents in the 10 villages with drinking water total As (T-As) level >50 µg/L and 10-50 µg/L were selected as an exposed group (n=420) and, <10 µg/L as a control group (n=185). Time-weighted average-As (TWA-As) intakes were calculated from T-As analysis of drinking water samples (DWS). Other metals in DWS, concentrations of T-As in urine and hair samples, urinary As species (S-As) (As (III), As (V), MMA-V and DMA-V), and some micronutrients in serum samples of residents were analyzed. Primary and secondary methylation indexes (PMI, SMI; respectively) were assessed from S-As concentrations. . Skin lesion presence was examined.
Results: TWA-As intake was 75.15 ppb in exposed group. Urinary and hair T-As and urinary S-As concentrations were significantly higher in exposed group (p<0.05). PMI and SMI values are revealed that methylation capacities of the residents were efficient and there was no saturation in As metabolism. No significant increase was observed in the frequency of skin lesions (hyperpigmentation, hypopigmentation, keratosis) of exposed group (p>0.05). Only frequency of keratosis either at hand or foot was higher in individuals with hair As concentration >1 µg/g (p<0.05).
Conclusion: Current study findings of chronic As exposure through drinking water of individuals living in the study area, could contribute to overall health risk assessment of regulatory agencies’ meta-analysis efforts on low-to moderate As exposure (<100 µg/L).
... Recently, several groups have helped establish the importance of evaluating methylation efficiency [%iAs, %monomethylarsonic acid (MMA), %dimethylarsinic acid (DMA)] in the eventual toxicity of arsenic. %MMA values in the urine are suggested to be linked to susceptibility to arsenic-induced health disorders (Lindberg et al., 2008;Huang et al., 2009;Shen et al., 2016;Skröder Löveborn et al., 2016;Rasheed et al., 2018). There appears to be two main methods to assess methylation capacity. ...
Epidemiological studies on chronic arsenic poisoning have clarified the relationship between various adverse effects and methylation efficiency or methylation capacity. However, no study has similarly investigated such effects on patients with acute arsenic poisoning. In the present work, we studied 61 patients with acute oral arsenic poisoning occurring after consumption of an arsenic trioxide-laced meal (curry soup). The cohort included children (defined as under 15 year old [y/o], n = 22) and adults (over 16 y/o, n = 39) whose urinary arsenic profiles were analyzed. None of these patients had received treatment with chelating agents. The estimated median (IQR) arsenic intake was 64.5 mg (48.3-80.5 mg) in children and 76.0 mg (56.0-91.0 mg) in adults, and these values were not significantly different. Symptoms of poisoning in children improved approximately 1 week after hospitalization. However, the symptoms in most adults deteriorated with severe signs of arsenic poisoning. Urinary arsenic profiles of all the patients were analyzed to obtain the following information: % monomethylarsonic acid (MMA), % dimethylarsinic acid (DMA), second methylation ratio (DMA/MMA), and secondary methylation index (SMI, DMA/MMA + DMA). The levels of these parameters may help identify patients at risk for worsening symptoms. %MMA, an indicator of incomplete methylation, increased more in adults, who experienced more severe symptom progression, compared with children. In contrast, %DMA, which indicates more complete and efficient methylation, increased particularly in children with mild symptoms. Overall the present results indicate that children possess an excellent capacity for methylation (second methylation ratio) of arsenic to DMA and therefore, experience relatively less severe progression of symptomology during acute arsenic poisoning.
... In recent years, natural contamination by arsenic in groundwater has received considerable attention in many countries around the world such as India, Bangladesh, Chile, and Taiwan [1][2][3][4]. In Vietnam, the issue of arsenic contamination in groundwater and drinking water was discovered in 2001, in which elevated As concentrations were found in various areas in the Red River Delta, northern Vietnam [5]. ...
Concentrations of As and other trace elements were measured in groundwater, rice, hair, urine, and blood samples of people consuming As-contaminated groundwater in a village of Ha Nam province, northern Vietnam to understand the recent status of contamination and assess the possible risks of human exposure. Elevated concentrations of As in groundwater were still observed, exceeding the WHO guideline value in most of the tube wells investigated. Significant positive correlations between As concentrations in groundwater and human samples (hair and urine) were observed. Arsenic concentrations in human and hair appeared to be related to the groundwater usage habit, with higher levels found in drinking group than those in the washing group. Significant good correlations were also encountered between cumulative intakes of As, Mn, and Ba through groundwater consumption and hair concentrations. All these results indicate the chronic exposure to As and some other elements such as Mn and Ba. The total intakes of As, Mn, and Ba through rice and groundwater consumption were estimated to be ranged from 80–836, 49.3–1850, and 311–97100 µ g/day, respectively. The daily intakes of As of the study area ranged from 1.6–16.7 µ g/kg body wt./day, mean: 7.15 µ g/kg body wt./day, in which about 85% of the subjects were above the provisional tolerable daily intake proposed by WHO.
... Mercury and dental amalgam toxicity studies have been conducted in several nations (Decharat et al. 2014;Akbal et al. 2014;Findik et al. 2016). Similarly, a number of human health-related studies of arsenic (Huang et al. 2009) and lead (Salem et al. 2000;Wasowicz et al. 2001) have also been carried out in different nations. It may be noted that minor studies on mercury in hair and urine samples in relation to mercury amalgam usage and fish consumption in children (Varkey et al. 2014) or fish consumption in dentists and other adults (Padma Kumar et al. 2015) in certain local areas in India are also already reported. ...
Toxic heavy metals such as arsenic (As), lead (Pb), and mercury (Hg) are systemic toxicants that are hazardous to human health. However, as these elements are increasing in the environment due to fast urbanization, industrialization, and chemicalized agricultural activities, accumulation of the same in human body anywhere in the world is quite interesting to global assessment of environment quality. In this connection, random examination of blood samples of human population in Kerala, South India, was carried out to assess the threat of heavy metal contamination to humans in this part of the globe, especially in relation to the amount of such metals in food and other environmental samples. Except pure vegetarians, people of Kerala consume rice as the staple food with a lot of fish. Therefore, the amount of these three heavy metals in drinking water, fish, rice, and paddy soils was done. Heavy metals in the blood were examined in relation to age, gender, and dietary habits such as frequency of fish eating or vegetarianism. Influence of dental amalgam fillings on blood mercury levels was also analyzed. Quantitative assessment of metals in samples was done by inductively coupled plasma-mass spectrometry (ICP-MS). The levels of arsenic, lead, and mercury were found well below the reference values, though diet seemed to pull them up as the amount of metals in blood showed significant differences between vegetarians and non-vegetarians. Evidence to the influence of dental amalgam fillings on blood mercury levels could not be established with the present samples.
... Lead, mercury, cadmium and arsenic cause human health problems worldwide and are systemic toxicants (Jan et al., 2015). Chronic arsenic exposure can affect almost all the systems of the body (Huang et al., 2009). Lead poisoning can occur even at low concentration and may cause neurological damage and adverse effects on other systems (Iwegbue et al., 2015). ...
People of Asian countries are very much conscious about complexion. This desire is exploited with advertisements of fairness creams in both the print and visual media which allure youngsters with promises of desired results. Skin lightening products occupy 61% of
dermatological market in India. Cosmetics are supposed to be safe and healthy, but research reports on their toxicities are available. Heavy metals are added intentionally or unintentionally to cosmetics, the presence of which, the consumers are mostly unaware of.
Arsenic, lead and mercury are top among hazardous systemic toxicants, which induce toxicity even at low levels of exposure. In this connection a survey was conducted among college
students and working women regarding the usage of fairness creams, which revealed that use of fairness creams, is common. As per the information gathered, four most commonly used brands of fairness creams in Kerala, India, were analysed for arsenic, lead and mercury by
ICP-MS. Although not in high levels, these were present in varying amounts in the four most commonly used brands of fairness creams. Analysis revealed the importance in choosing cosmetics with caution and to minimize the usage as far as possible.
