Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis

Abstract

Abstract:Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (p < 0.000001) following arsenic exposure: inorganic arsenic (iAs), monomethyl arsenic (MMA), dimethyl arsenic (DMA), and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD): 1.00; 95% confidence interval (CI): 0.60-1.40; p < 0.00001) and MMA (SMD: 0.49; 95% CI: 0.21-0.77; p = 0.0006) also increase, while the percentage of DMA (SMD:´0.57; 95% CI: 0.80-´0.31; p < 0.0001), primary methylation index (SMD:´0.57; 95% CI:´0.94-´0.20; p = 0.002), and secondary methylation index (SMD:´0.27; 95% CI:´0.46-´0.90; p = 0.004) decrease. Smoking, drinking, and older age can reduce arsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

Water Dilutes and Alcohol Concentrates Urinary Arsenic Species When Food is the Dominant Source of Exposure

“…Therefore, the 2 nd collected urine profile of each participant was considered for further analysis. Although women have shown more efficient methylation capacity than men in previous studies (Lindberg et al 2008;Hudgens et al 2016;Shen et al 2016), gender was not a significant predictor of As exposure in the current study.…”

A retrospective review of the dermatologic manifestations of chronic arsenic poisoning in the Philippines

“…Arsenic methylation facilitates metabolism of inorganic arsenic into less toxic metabolites that are readily eliminated from the body . Other factors that can affect arsenic metabolism include gender, smoking, drinking, body mass index, and genetic polymorphisms found within a population. These factors should be taken into consideration in future health assessment activities within and around the affected municipality.…”

Arsenic and fasting blood glucose in the context of other drinking water chemicals: a cross-sectional study in Bangladesh

“…Because sex [19][20][21][22][23][24] and BMI [24][25][26][27] have been associated in several studies with arsenic toxicokinetics and the related one-carbon metabolism pathway, we considered possible effect modification of the hypothesized arsenic toxicity, by sex and by BMI categories, using models with interaction terms between BMI category and arsenic category, or sex and arsenic category, and adjustment for the same suite of confounders as in our fully adjusted main analyses (Model 4).…”