Urinary dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) are among the commonly used biomarkers for inorganic arsenic (iAs) exposure, but may also arise from seafood consumption and organoarsenical pesticide applications. We examined speciated urinary arsenic data from National Health and Nutrition Examination Survey (NHANES) 2009-2010 cycle to assess potential correlations among urinary DMA, MMA, and the organic arsenic species arsenobetaine. Urinary DMA and MMA were positively associated with urinary arsenobetaine, suggesting direct exposure to these species in seafood or metabolism of organic arsenicals to these species, although the biomonitoring data do not directly identify the sources of exposure.
View Article and Find Full Text PDFObjective: The purpose of this review is to evaluate the impact of recent epidemiologic literature on the National Research Council (NRC) assessment of the lung and bladder cancer risks from ingesting low concentrations (< 100 µg/L) of arsenic-contaminated water.
Data Sources, Extraction, And Synthesis: PubMed was searched for epidemiologic studies pertinent to the lung and bladder cancer risk estimates from low-dose arsenic exposure. Articles published from 2001, the date of the NRC assessment, through September 2010 were included.
An independent peer expert panel was convened under the auspices of the Alliance for Risk Assessment (ARA) to review toxicology data and derive oral Reference Doses (RfDs) for four environmental degradates of the acetanilide herbicides, alachlor and acetochlor. The degradates included in this evaluation were (1) alachlor tertiary-ethanesulfonic acid (ESA), (2) alachlor tertiary-oxanilic acid (OXA), (3) acetochlor ESA, and (4) acetochlor OXA. Each degradate was judged to have sufficient data for developing low to medium confidence RfD, with use of an additional uncertainty factor (UF) to cover data gaps.
View Article and Find Full Text PDFThe chronic exposure of humans through consumption of high levels of inorganic arsenic (iAs)-contaminated drinking water is associated with skin lesions, peripheral vascular disease, hypertension, and cancers. Additionally, humans are exposed to organic arsenicals when used as pesticides and herbicides (e.g.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
January 2005
Protein levels and polymorphisms of p22(phox) have been suggested to modulate vascular NAD(P)H oxidase activity and vascular production of reactive oxygen species (ROS). We sought to determine whether increasing p22(phox) expression would alter vascular ROS production and hemodynamics by targeting p22(phox) expression to smooth muscle in transgenic (Tg) mice. Aortas of Tg(p22smc) mice had increased p22(phox) and Nox1 protein levels and produced more superoxide and H(2)O(2).
View Article and Find Full Text PDF