Environmental Engineering Reference
In-Depth Information
Ecotoxicological Impacts on Brown Trout
(
Salmo trutta
L.) Exposed to Runoff from a
Four Lane Motorway in Norway
Sondre Meland, Bjørn Olav Rosseland, and Brit Salbu
Introduction
In the last decades there has been a growing concern regarding highway runoff as
a potential hazard to receiving water bodies. This has led to increasing use of vari-
ous treatment systems. A lot of the pollutants are believed to be associated with
particles, and most of the treatment systems are therefore based on removing the
pollutants by sedimentation. However, treatment of particle bound pollutants might
be inappropriate in protecting the aquatic biota because toxicity, at least for metals,
is mostly related to the dissolved fraction which includes colloids as well as the low
molecular mass positively charged metal species
[1]
. In northern countries, like
Norway, road salt is frequently used in the winter maintenance to achieve good
friction on the road. The sodium and chloride concentrations can thus be rather high
during runoff episodes and might lead to increased mobility, remobilization and
finally increased bioavailability of the metals
[2-5]
.
Pollutants often found in elevated concentrations in highway runoff such as
nickel (Ni), cadmium (Cd), zinc (Zn), copper (Cu), lead (Pb) and polycyclic aro-
matic hydrocarbons (PAH) are in several studies shown to potentially disturb nor-
mal homeostasis in fish, for example increased enzymatic activity (as well as
inhibition), osmoregulatory- and respiratoric dysfunctions
[1, 6-8]
.
This paper gives an overview of results obtained from one out of four simulated
runoff episodes entering a highway retention pond system, and describes the chemi-
cal exposure concentrations and physiological responses in the native fish species
brown trout (
Salmo trutta
L.).
S. Meland, B.O. Rosseland, and B. Salbu
Department of Plant and Environmental Sciences, Norwegian University of Life Sciences,
P.O. Box 5003,N-1432 Ås, Norway
