Inhibition of mussel suspension feeding by surfactants of three classes

Inhibition of mussel suspension feeding by surfactants of three classes
S. A. Ostroumov1,* & J. Widdows2
1Department of Hydrobiology, Faculty of Biology, Moscow State University, 119992, Moscow, Russia
2Plymouth Marine Laboratory, Prospect Place, West Hoe, PL1 3DH, Plymouth, England
http://www.scribd.com/doc/45958156/;
scribd.com/doc/59544597/;
http://moscowstate.academia.edu/SergeiOstroumov/Papers/806726/Ostroumov_S.A._Widdows_J._Inhibition_of_mussel_suspension_feeding_by_surfactants_of_three_classes._-_Hydrobiologia._2006._Vol._556_No.1._P._381_-_386._http_www.scribd.com_doc_45958156_scribd.com_doc_59544597_;

Key words: surfactants, filter-feeders, clearance rates, marine mussels, toxicity
Abstract
Effects of three surfactants on the filtration rates by marine mussels were studied. The xenobiotics tested
represented anionic, cationic and non-ionic surfactants (tetradecyltrimethylammonium bromide, a representative
of a class of cationic surfactants; sodium dodecyl sulphate, a representative of anionic alkyl sulfates;
and Triton X-100, a representative of non-ionic hydroxyethylated alkyl phenols). All three surfactants
inhibited the clearance rates. The significance of the results for the ecology of marine ecosystems is discussed.
Abbreviations: CR – clearance rate; EMIS – the electromagnetic induction system; SDS – sodium dodecyl
sulphate; TDTMA – tetradecyltrimethylammonium bromide; TX100 – Triton X-100
Introduction
Suspension feeders (filter-feeders) play a significant
functional role in aquatic ecosystems. The important
role of filter-feeders (particularly molluscs) is
due to their high rates and volumes of water filtration
(Walz, 1978; Alimov, 1981; Jørgensen
et al., 1986; Kryger & Riisga˚ rd, 1988; Shulman &
Finenko, 1990; Zaika et al., 1990; Dame, 1996). As
a result of biological filtration, suspended particles
and cells of phytoplankton and microbial plankton
are removed from the water. This process also
accelerates mineralization of organic substances in
the filtered matter. Therefore, biological filtration
contributes significantly to water purification in
aquatic ecosystems.
Filter-feeders can accelerate carbon fluxes in
ecosystems, because the production of biodeposits
(faecal and pseudofaecal pellets) leads to enhanced
rates of sedimentation. As a result, bivalves were
shown to influence material flux at the sediment–
water interface (Smaal et al., 1986; Kautsky &
Evans, 1987; Jaramillo et al., 1992; Dame, 1996;
Widdows et al., 1998).
Biodeposition rates were estimated as high as
60 gm)2 h)1 at a density of 1400 mussels m)2 (i.e.,
50% surface cover) in a mussel (Mytilus edulis)
bed at Cleethorpes (Humber estuary, England)
(Widdows et al., 1998), which is higher than
maximum recorded biodeposition rates of
25 gm)2 h)1 for M. edulis in the Oosterschelde in
the Netherlands (Smaal et al., 1986) and
18 gm)2 h)1 for M. chilensis in an estuary in Chile
(Jaramillo et al., 1992). Biodeposition rates in
some ecosystems were up to 40 times the natural
sedimentation rates. Kautsky & Evans (1987)
estimated annual biodeposition per g mussel (M.
edulis, dry weight including shells) as high as
1.76 g dry weight, 0.33 g ash-free dry weight,
0.13 g carbon, 1.7�10)3 g nitrogen and
2.6�10)4 g phosphorus. The annual biodeposition
is 11.7 g dry weight per g mussel shell-free dry
weight. When average mussel biomass was
620 gm)2 (dry weight including shells) or 91 gm)2
(dry flesh weight), the annual biodeposition per m2
was 1092 g (dry weight), including 80.7 g C, 10.4 g
N, 1.6 g P (Kautsky & Evans, 1987). The average
composition during the year, expressed as percent