ac9b04681_si_001.pdf (2.08 MB)
Identification of Degradation Products of Sea-Dumped Chemical Warfare Agent-Related Phenylarsenic Chemicals in Marine Sediment
journal contribution
posted on 2020-03-13, 19:39 authored by Hanna Niemikoski, Martin Söderström, Harri Kiljunen, Anders Östin, Paula VanninenPreviously
unknown phenylarsenic chemicals that originated from
chemical warfare agents (CWAs) have been detected and identified in
sediment samples collected from the vicinity of chemical munition
dumpsites. Nontargeted screening by ultrahigh-performance liquid chromatography–high-resolution
mass spectrometry (UHPLC-HRMS) was used for detection of 14 unknown
CWA-related phenylarsenic chemicals. Methylated forms of Clark I/II,
Adamsite, and phenyldichloroarsine were detected in all analyzed sediment
samples, and their identification was based on synthesized chemicals.
In addition, other previously unknown CWA-related phenylarsenic chemicals
were detected, and their structures were elucidated using MS/HRMS
technique. On the basis of relative isotope ratios of protonated molecules
and measures of exact masses of formed fragment ions, it could be
concluded that some of these unknown chemicals contained a sulfur
atom attached to an arsenic atom. In addition to that, some of the
samples contained chemicals that had formed via addition of an OH
group to the aromatic ring. However, it is not possible to say how
these chemicals are formed, but the most plausible cause is activities
of marine microbes in the sediment. To our knowledge, these chemicals
have not been detected from sediment samples previously. Sensitive
analytical methods are needed for these novel chemicals to assess
the total CWA burden in marine sediments, and this information is
essential for the risk assessment.