Emissions of volatile organic sulfur (S), selenium (Se),
bromine
(Br), and iodine (I) species from aquatic ecosystems represent an
important source of these elements into the atmosphere. Available
methods to measure these species are either not sensitive enough or
not automated, which hinder a full understanding of species distribution
and production mechanisms. Here, we present a sensitive and high-throughput
method for the simultaneous and comprehensive quantification of S,
Se, Br, and I volatile organic species in atmospheric and aqueous
samples using a preconcentration step onto sorbent tubes and subsequent
analysis by thermal desorption coupled to gas chromatography and inductively
coupled plasma mass spectrometry (TD-GC-ICP-MS). Selected commercially
available sorbent tubes, consisting of mixed porous polymer and graphitized
black carbon, offered the highest trapping capacity and lowest loss
of species when stored at −20 °C for 28 days after sampling.
After optimization of the TD-GC-ICP-MS method, absolute detection
limits were better than 3.8 pg, 9.1 fg, 313 fg, and 50 fg, respectively,
for S, Se, Br, and I species. As a proof of concept, the concentrations
of target species were determined in aqueous and continuously collected
atmospheric samples during a cruise in the Baltic and North Seas.
Moreover, unknown S, Br, and I volatile species were detected in both
aqueous and atmospheric samples demonstrating the full potential of
the method.