Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Nov 7;51(21):12210-12218.
doi: 10.1021/acs.est.7b04356. Epub 2017 Oct 17.

Elevated Trimethylarsine Oxide and Inorganic Arsenic in Northern Hemisphere Summer Monsoonal Wet Deposition

Affiliations

Elevated Trimethylarsine Oxide and Inorganic Arsenic in Northern Hemisphere Summer Monsoonal Wet Deposition

Laurie Savage et al. Environ Sci Technol. .

Abstract

For arsenic speciation, the inputs for wet deposition are not well understood. Here we demonstrate that trimethylarsine oxide (TMAO) and inorganic arsenic are the dominant species in monsoonal wet deposition in the summer Indian subcontinent, Bangladesh, with inorganic arsenic dominating, accounting for ∼80% of total arsenic in this medium. Lower concentrations of both species were found in monsoonal wet deposition in the winter Indian subcontinent, Sri Lanka. The only other species present was dimethylarsinic acid (DMAA), but this was usually below limits of detection (LoD). We hypothesize that TMAO and inorganic arsenic in monsoonal wet deposition are predominantly of marine origin. For TMAO, the potential source is the atmospheric oxidation of marine derived trimethylarsine. For inorganic arsenic, our evidence suggests entrainment of water column inorganic arsenic into atmospheric particulates. These conclusions are based on weather trajectory analysis and on the strong correlations with known wet deposition marine derived elements: boron, iodine, and selenium. The finding that TMAO and inorganic arsenic are widely present and elevated in monsoonal wet deposition identifies major knowledge gaps that need to be addressed regarding the understanding of arsenic's global cycle.

Similar articles

See all similar articles

Cited by 1 article

LinkOut - more resources

Feedback