TY - JOUR
T1 - Suspended particles only marginally reduce pyrethroid toxicity to the freshwater invertebrate Gammarus pulex (L.) during pulse exposure
AU - Rasmussen, Jes
AU - Cedergreen, Nina
AU - Kronvang, Brian
AU - Bjergager, Maj-Britt Andersen
AU - Nørum, Ulrik
AU - Kretschmann, Andreas Christopher
AU - Strobel, Bjarne W.
AU - Hansen, Hans Chr. Bruun
PY - 2016
Y1 - 2016
N2 - Current ecotoxicological research on particle associated pyrethroids in freshwater systems focuses almost exclusively on sediment-exposure scenarios and sediment-dwelling macroinvertebrates. We studied how
suspended particles influence acute effects of lambda-cyhalothrin and bifenthrin on the epibenthic freshwater amphipod Gammarus pulex (L.) using brief pulse exposures followed by a 144 h post exposure recovery phase. Humic acid (HA) and the clay mineral montmorillonite (MM) were used as model sorbents in environmentally
realistic concentrations (5, 25 and 125 mg L-1). Mortality of G. pulex was recorded during the post exposure recovery phase and locomotor behavior was measured during exposure to lambda-cyhalothrin. We found that HA in
concentrations ≥25 mg L-1 adsorbed the majority of
pyrethroids but only reduced mortality of G. pulex up to a
factor of four compared to pyrethroid-only treatments. MM
suspensions adsorbed a variable fraction of pyrethroids
(10% for bifenthrin and 70% for lambda-cyhalothrin) but
did not significantly change the concentration–response
relationship compared to pure pyrethroid treatments.
Behavioral responses and immobilisation rate of G. pulex
were reduced in the presence of HA, whereas behavioral
responses and immobilisation rate were increased in the
presence of MM. This indicates that G. pulex was capable
of sensing the bioavailable fraction of lambda-cyhalothrin.
Our results imply that suspended particles reduce to only a
limited extent the toxicity of pyrethroids to G. pulex and
that passive uptake of pyrethroids can be significant even
when pyrethroids are adsorbed to suspended particles.
AB - Current ecotoxicological research on particle associated pyrethroids in freshwater systems focuses almost exclusively on sediment-exposure scenarios and sediment-dwelling macroinvertebrates. We studied how
suspended particles influence acute effects of lambda-cyhalothrin and bifenthrin on the epibenthic freshwater amphipod Gammarus pulex (L.) using brief pulse exposures followed by a 144 h post exposure recovery phase. Humic acid (HA) and the clay mineral montmorillonite (MM) were used as model sorbents in environmentally
realistic concentrations (5, 25 and 125 mg L-1). Mortality of G. pulex was recorded during the post exposure recovery phase and locomotor behavior was measured during exposure to lambda-cyhalothrin. We found that HA in
concentrations ≥25 mg L-1 adsorbed the majority of
pyrethroids but only reduced mortality of G. pulex up to a
factor of four compared to pyrethroid-only treatments. MM
suspensions adsorbed a variable fraction of pyrethroids
(10% for bifenthrin and 70% for lambda-cyhalothrin) but
did not significantly change the concentration–response
relationship compared to pure pyrethroid treatments.
Behavioral responses and immobilisation rate of G. pulex
were reduced in the presence of HA, whereas behavioral
responses and immobilisation rate were increased in the
presence of MM. This indicates that G. pulex was capable
of sensing the bioavailable fraction of lambda-cyhalothrin.
Our results imply that suspended particles reduce to only a
limited extent the toxicity of pyrethroids to G. pulex and
that passive uptake of pyrethroids can be significant even
when pyrethroids are adsorbed to suspended particles.
U2 - 10.1007/s10646-016-1609-y
DO - 10.1007/s10646-016-1609-y
M3 - Journal article
C2 - 26831865
VL - 25
SP - 510
EP - 520
JO - Ecotoxicology
JF - Ecotoxicology
SN - 0963-9292
IS - 3
ER -