Toxicity Effects of Anionic Surfactants Sodium
Dodecyl Sulphate (SDS) to Planarian Dugesia
japonica
Zuoqing Yuan


Sodium dodecyl Sulphate (SDS) is a kind
of anionic surfactant that denatures membrane
proteins of cells. It is used in detergents,
household cleaning products, and in the mining
and oil industries. It can be present in sufficient
concentrations to constitute toxicity problems to
aquatic organisms in untreated effluents.
Freshwater planarians have the ability to regenerate
their whole body from a small piece of the body, so they
have been widespread applied in developmental biology
and neuroscience research. Furthermore, they have a high
sensitivity to toxins with widespread application in
toxicological and genotoxicity studies.

In this study we used planarians Dugesia
japonica,
which
belong
to
the
phylum
Platyhelminthes, class Turbellaria, order Tricladida,
family Dugesiidae, as an animal assay.

The purpose of this study was to evaluate
aquatic toxicity of SDS by examining the effects of
SDS on survival, behavior, regrowth of the head and
antioxidant activity in planarians D. japonica.
Mean lethal concentration (LC50)


Daphnia magna has been suggested to be the most
sensitive species to surfactants. Data on SDS toxicity
obtained from the 48-h planarian toxicity test in our
study was 5.8 mg/L.
However, data on SDS toxicity obtained from the 48h Daphnia magna test in the literature was 6.2-9 mg/L.
Thus, planarians Dugesia japonica also have highly
sensitivity to SDS among aquatic organisms.
Fig. 1 Mortality of D. japonica exposed to SDS after 1-h exposure.
Fig. 2 Effect of SDS in planarian motility.
Fig. 3 Recovery of SDS exposure.
eyespots
auricles
Fig.4 Regeneration performance of regenerating planarians
exposed to different concentrations of SDS.

Our results showed that the appearance of auricles was
easier affected by SDS than that of eyespots in the
decapitated D. japonica fragments. Therefore, the auricle
tissues in regenerating planarians might be a potential
biomarker for SDS (and possibly other surfactants)
pollution.
Fig.6 Changes in activities of SOD (units/mg protein) in regenerating
planarians exposed to different concentrations of SDS.
Fig. 7 Changes in activities of CAT (units/mg protein) in regenerating
planarians exposed to different concentrations of SDS.

The enzymatic antioxidant defenses of regenerating
planarians were significantly altered by SDS. The
increase in antioxidant enzyme activities could
primarily be a response to the SDS.
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We can conclude that planarian D.japonica can be
applied as a good bioindicator organism for the
evaluation of SDS (and possibly other surfactants)
effects upon freshwater invertebrates in a freshwater
environment.