Arsenic Species in a Rocky Intertidal Marine Food Chain in NSW, Australia, revisited

Simon Foster; William Maher; Ernst Schmeisser; Anne Taylor; Frank Krikowa; Simon Apte

doi:10.1071/EN06026

RESEARCH ARTICLE

Previous Next Contents Vol 3(4)

Arsenic Species in a Rocky Intertidal Marine Food Chain in NSW, Australia, revisited

Simon Foster ^A ^D , William Maher ^A , Ernst Schmeisser ^B , Anne Taylor ^A , Frank Krikowa ^A and Simon Apte ^C

+ Author Affiliations

- Author Affiliations

^A Ecochemistry Laboratory, Institute of Applied Ecology, University of Canberra, Belconnen, ACT 2601, Australia.

^B Karl-Franzens University of Graz, Institute of Chemistry—Analytical Chemistry, Graz 8010, Austria.

^C Centre for Environmental Contaminants Research, CSIRO Energy Technology, Bangor, NSW 2234, Australia.

^D Corresponding author. Email: foster@aerg.canberra.edu.au

Environmental Chemistry 3(4) 304-315 https://doi.org/10.1071/EN06026
Submitted: 20 April 2006 Accepted: 10 August 2006 Published: 5 September 2006

Environmental Context. The pathways by which arsenic is accumulated, biotransformed and transferred in aquatic ecosystems are relatively unknown. Examination of whole marine ecosystems rather than individual organisms provides greater insights into the biogeochemical cycling of arsenic. Rocky intertidal zones, which have a high abundance of organisms but low ecological diversity, are an important marine habitat. This study examines the cycling of arsenic within intertidal ecosystems to further understand its distribution and transfer.

Abstract. The present study reports total arsenic and arsenic species in a short rocky intertidal marine food chain in NSW, Australia. Total mean arsenic concentrations increased up the food chain in the following order: 4 ± 2 µg g^–1 in attached rock microalgae, 31 ± 14 µg g^–1 in Bembicium nanum Lamarck, 45 ± 14 µg g^–1 in Cellana tramoserica Sowerby, 58 ± 14 µg g^–1 in Nerita atramentosa Reeve, 75 ± 15 µg g^–1 in Austrocochlea constrica Lamarck (a herbivore) and 476 ± 285 µg g^–1 in the carnivore Morula marginalba Blainville. Significant differences in arsenic concentrations of B. nanum, N. atramentosa and M. marginalba were found among locations and may be related to food availability, spawning or differences in age and/or size classes of individuals. Significant differences in arsenic concentrations were also found within locations among species, and increased in the order: rock microalgae < B. nanum < C. tramoserica < N. atramentosa < A. constricta < M. marginalba. Although small differences in total arsenic concentrations were found among locations for some gastropod species, arsenic species proportions were very consistent within gastropod species across locations. The majority of arsenic in Homosira banksii (macroalgae) was oxo-arsenoribosides, with thio-arsenoribosides making up ~10% of the total methanol–water extractable arsenic. The rock microalgae contained arsenobetaine (AB) (59 ± 5%) and arsenoribosides (36 ± 15%). The AB content of the herbivores B. nanum, N. atramentosa and A. constricta ranged from 71 to 95%, and that of the carnivore M. marginalba was 98%. Most gastropods contained thio-arsenosugars (up to 13 ± 3% of total extractable arsenic), with C. tramoserica containing higher proportions of thio-phosphate arsenoriboside (7 ± 2%) and lower proportions of AB (69 ± 4%). Glycerol trimethylarsonioribosides (1.4 ± 0.1%) were also found in most of the herbivorous gastropods. Oxo-dimethylarsinoylethanol (oxo-DMAE) was found in N. atramentosa (<1%).

Keywords. : biotransformation — ecosystems — living organisms — marine chemistry

Acknowledgements

We thank the University of Canberra’s Ecochemistry class of 2005 for assistance with field sampling and sample preparation. Financial support from the Austrian Science Found (FWF) under project number P16088-NO3 and University of Canberra’s visiting scholars grant for E.S. and University of Canberra’s Vice Chancellors scholarship for S.F. is gratefully acknowledged.

References

Arsenic Species in a Rocky Intertidal Marine Food Chain in NSW, Australia, revisited

Acknowledgements

Subscriber Login