ISSN 0096-3925, Moscow University Biological Sciences Bulletin, 2007, Vol. 62, No. 4, pp. 176–179. © Allerton Press, Inc., 2007. Original Russian Text © E.A. Solomonova, S.A. Ostroumov, 2007, published in Vestnik Moskovskogo Universiteta. Biologiya, 2007, No. 4, pp. 39–42.
Tolerance of an Aquatic Macrophyte Potamogeton crispus L. to Sodium Dodecyl Sulphate E. A. Solomonova and S. A. Ostroumov Department of Hydrobiology; e-mail:
[email protected] Received April 17, 2006
Abstract—The effects of the anionic surfactant sodium dodecyl suplphate on the aquatic macrophyte Potamogeton crispus L. are studied. Concentrations of 83–133 mg/l caused fragmentation of the stems of plants. The tolerance of the plants to the negative effects of the surfactant was higher in the spring (April) than in the autumn (September). DOI: 10.3103/S0096392507040074
Macrophytes are important components of ecosystems and participate in the purification of water and support its quality (McCutcheon and Schnoor, 2003; Wetzel, 2001). This is especially important in conditions of pollution of water bodies and water courses. Surfactants constitute a class of pollutants. The ecological danger of surfactants is still insufficiently investigated and analyzed. On the one hand, there are numerous publications on various bioeffects and disturbances of the structure and function of organisms under the action of synthetic surfactants (Davydov et al., 1997; Ostroumov, 2001, 2005, 2006). On the other hand, some authors do not qualify surfactants as major pollutants (Moore and Ramamoorthy, 1984) and believe that, ecologically, they are not highly dangerous for aquatic ecosystems (Fendinger et al., 1994). On the basis of studies of the effect of surfactants and surfactant-containing mixtures and the elucidation and comparison of the tolerance of organisms belonging to different taxa, it was suggested to use angiospermous plants for phytoremediation (Ostroumov, 2001). In this aspect, further investigation and clarification of the facts concerning the interaction of plants and various xenobiotics are necessary. The present paper presents the results of investigations of the effect of various concentrations of aqueous solutions of the anionic surfactant sodium dodecyl sulphate (SDS) on the viability of the aquatic macrophyte pondweed Potamogeton crispus L. MATERIAL AND METHODS In the experiments with the pondweed, two–four stems with a combined biomass of 7.0–7.5 g were placed in vessels with tap water (volume 1.2 l) preliminarily allowed to settle for 48 hours. The prepared stock solution of SDS in water (concentration of 2 mg/ml) was added to the vessels at intervals of 48 h for 20 days. The volume of the added solution in the case of a single addition was 0.10, 0.20, 0.30, 0.50, 1.00, 5.00, 10.00,
and 30.00 ml. The increment of the concentration of SDS was 0.17, 0.33, 0.50, 0.83, 1.67, 8.30, 16.60, and 49.80 mg/l, respectively. Also, a series of experiments was arranged with a single introduction of SDS. In this case, the concentration of SDS in the vessels was 83.3, 100.0, and 133.3 mg/l, respectively. The experiments were carried out with the water temperature in the vessels being 19–23°C with normal room illumination in April and September. The level of the effect of SDS on the macrophytes was estimated using a 10-point scale. In the elaboration of the scale, several visual characteristics of the state of the plants were taken into consideration, including the separation of the stem fragments and the separation of the leaves and their pigmentation (Table 1). RESULTS AND DISCUSSION The experiments with pondweed collected in September demonstrated that, when the sum total of the added SDS attained 6.68 mg/l (eight days into the experiment), the turgor of the stems decreased (Table 2). At the same stage of the experiment in the vessels with the sum total of SDS from 33.20 to 199.20 mg/l, considerable fragmentation was observed (Table 2): at 33 mg/l, the level of impact of the SDS was 9 points; at 199 mg/l, it was 10 points. In April, a decrease of the turgor was recorded when the sum total of the SDS attained 3.32 mg/l (8 days into the experiment). However, in April, the process of fragmentation in the vessels with higher concentrations of SDS developed less intensively than in the experiments carried out in September. In April, in the vessels with the sum total of the SDS equal to 33 mg/l, the level of the impact of the SDS was only equal to one point (Table 3). Thus, in the autumn, the tolerance of the pondweed to SDS (four additions of the aqueous solution of SDS were added over eight days) was somewhat lower than in the spring. The relatively high tolerance of the pond-
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Table 1. Scale of impact of sodium dodecyl sulphate (SDS) on the structural integrity of macrophytes Points
Characteristics of fragmentation of stems
0 1 2 3 4 5 6
Absence of fragmentation and signs preceding it Decrease of turgor of stems (reversible stage) Fracture of stems in 1–2 areas of the total mass of the plants Separation of 1–2 parts of the stems in the total mass of the plants Most plants (but not all) are fragmented All plants are fragmented, 50% of the fragments are 6 cm long and longer All the plants are fragmented, over 50% of the fragments are relatively short (less than 6 cm). Three or more relatively longer fragments are present, 6 cm long and longer Most fragments are relatively small, shorter than 6 cm. One–two relatively long fragments are present (6 cm and longer) All the fragments are shorter than 6 cm All the fragments are less than 4 cm in length and are on the bottom of the vessel, most of the fragments retain leaf pigmentation All the fragments are shorter than 4 cm and are on the bottom of the vessel, more than 50% of the leaves are separated, the leaf blades are decaying, depigmentation is expressed
7 8 9 10
Note: For the determination of the level of fragmentation applying the present scale, the vessels were used with not less than three plants having a stem length from 12 to 30 cm.
Table 2. Level of the effect of SDS on the structural integrity of the stems of P. crispus L. in 8 days** (September) No. of vessel
Biomass (wet weight) (g)
Quantity of SDS in the addition (mg)
Increment of the concentration of SDS (mg/l)
Sum of the addition of SDS (mg/l)
Fragmentation level*
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
7.0 7.0 7.1 7.0 7.3 7.0 7.2 7.0 7.0 7.3 7.0 7.1 7.3 7.4 7.0 7.0
0.00 0.00 0.20 0.20 0.40 0.40 0.60 0.60 1.00 1.00 1.00 1.00 10.00 10.00 20.00 60.00
0.00 0.00 0.17 0.17 0.33 0.33 0.50 0.50 0.83 0.83 1.67 1.67 8.30 8.30 16.60 49.80
0.00 0.00 0.68 0.68 1.32 1.32 2.00 2.00 3.32 3.32 6.68 6.68 33.20 33.20 66.40 199.20
0 0 0 0 0 0 0 0 0 0 1 1 9 9 10 10
* The level of impact of the SDS on the macrophytes was estimated using a 10-point scale. ** Four additions were performed within eight days.
weed in the spring was also confirmed under the conditions of a longer experiment when the series of additions continued for 20 days (Table 4).
one day after the introduction of the SDS solution, the level of the impact was one point. The stems were fully fragmented 6 days into the experiment (Table 5).
At a simultaneous addition in September of comparatively high doses of SDS (83.3, 100.0, and 133.3 mg/l),
In the literature, there are data on investigations of other macrophytes in which the processes of decompo-
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Table 3. Level of the effect of SDS on the structural integrity of stems of P. crispus L. in 8 days** (April) No. of vessel
Biomass (wet weight) (g)
Quantity of SDS in the addition (mg)
Increment of the concentration of SDS (mg/l)
Sum of the addition of SDS (mg/l)
Fragmentation level*
1 2 3 4 5 6 7 8 9 10 11 12 13 14
7.3 7.0 7.1 7.0 7.0 7.0 7.2 7.0 7.0 7.0 7.1 7.4 7.0 7.0
0.0 0.0 0.6 0.6 1.0 1.0 2.0 2.0 10.0 10.0 20.0 20.0 60.0 60.0
0.00 0.00 0.50 0.50 0.83 0.83 1.67 1.67 8.30 8.30 16.60 16.60 49.80 49.80
0.00 0.00 2.00 2.00 3.32 3.32 6.68 6.68 33.20 33.20 66.40 66.40 199.20 199.20
0 0 0 0 1 1 1 1 1 1 9 9 10 10
* The level of impact of the SDS on the macrophytes was estimated using a 10-point scale. ** Four additions were made within eight days.
Table 4. Level of the effect of SDS on the structural integrity of stems of P. crispus L. in 20 days** (April) No. of vessel
Biomass (wet weight) (g)
Quantity of SDS in the addition (mg)
Increment of the concentration of SDS (mg/l)
Sum of the addition of SDS (mg/l)
Fragmentation level*
1 2 3 4 5 6 7 8 9 10 11 12 13 14
7.3 7.0 7.1 7.0 7.0 7.0 7.2 7.0 7.0 7.0 7.1 7.4 7.0 7.0
0.0 0.0 0.6 0.6 1.0 1.0 2.0 2.0 10.0 10.0 20.0 20.0 60.0 60.0
0.00 0.00 0.50 0.50 0.83 0.83 1.67 1.67 8.30 8.30 16.60 16.60 49.80 49.80
0.00 0.00 5.00 5.00 8.30 8.30 16.70 16.70 83.00 83.00 166.00 166.00 199.20 199.20
0 0 1 1 1 1 1 1 1 1 – – – –
* The level of impact of SDS on the macrophytes was estimated using a 10-point scale. ** Ten additions were made within 20 days (in vessel nos. 13 and 14, four additions were made during eight days; within eight days in these vessels, 100% destruction of the plants was observed at the cumulative addition of 199.20 mg/l of SDS).
sition and destruction of plants were studied as part of the natural processes of dying off; destruction; organic detritus formation; and, finally, mineralization of vegetative biomass (e.g., Gamage and Asaeda, 2005). How-
ever, these studies did not involve the impact of xenobiotics on the decomposition of macrophytes. On the whole, the obtained results supplement the available knowledge on the sensitivity and tolerance of
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Table 5. Level of the effect of SDS on the macrophytes P. crispus L. after a single addition of SDS (September) No. of vessel
Biomass (wet weight) (g)
17 18 19
7.0 7.0 7.1
Quantity of SDS Concentration of in the addition SDS in the vessel (mg) (mg/l) 100.0 120.0 160.0
83.33 100.00 133.33
Fragmentation level* in 1 day
in 2 days
in 3 days
in 6 days
1 1 1
4 5 5
5 5 5
9 9 9
* The level of impact of SDS on the macrophytes was estimated using a 10-point scale.
plants to synthetic surfactants (Ostroumov, 2001, 2006). The revealed impact of the seasons on the tolerance of the plants to the series of additions of surfactants agrees with the previously described facts concerning the influence of the seasons on the sensitivity of aquatic plants to other xenobiotics (Kuz’mitskaya, 1999). The obtained results are promising with respect to phytoremediation of polluted sites. (Ulanova and Ostroumov, 1999; McCitcheon and Schnoor, 2003). SUMMARY (1) The obtained data supply additional characteristics of the sensitivity and tolerance of plants exposed to pollutants of the surfactant class. (2) The significance of the seasons for the tolerance of macrophytes to surfactants is shown. (3) The role of the size of the addition of the surfactant in the series of repeated additions has been shown to influence the manifestation or absence of a negative effect at the end of the series of additions. (4) Some of the obtained data may be important for the determination of permissible loads of pollutants of the surfactant class in water bodies overgrown with macrophytes. REFERENCES Davydov, O.N., Balakhnin, I.A., Kalenichenko, K.P., and Kurovskaya, L.Ya., Adsorption and Desorption of Cationic Surfactants by the Preparation Aerosil and its Effect on Immuno-Physiological Parameters of Blood of Carp, Gidrobiologicheskii Zh., No. 2, 68–75 (1997). Fendiger, N., Versteeg, D., Weeg, E., Dyer, S., and Rapaport, R., Environmental Behavior and Fate of Anionic Surfactants, in Environmental Chemistry of Lakes and Reservoirs (Washington, D.C., 1994), 527–557. Gamage, N. and Asaeda, T., Decomposition and Mineralization of Eichhornia crassipes litter under Aerobic Conditions with and without Bacteria, Hydrobiologia 541, 13–27 (2005).
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Khristoforova, N.K., Aizdaicher, N.A., and Berezovskaya, O.Yu., Effect of Ions of Copper and of a Detergent on Green Microalgae Dunaliella tertiolecta and Platymonas sp., Biologiya Morya, No 2, 114–119 (1996). Kuz’mitskaya, I.V., Sensitivity of Elodea canadensis to Potassium Bichromate, in Vodnye organizmy i ekosistemy 1 (Moscow, 1999). McCutcheon, S. and Schnoor, S., Phytoremidiation: Transformation and Control of Contaminants. Environmental Science and Technology (A. Wiley–Interscience Series of Texts and Monographs, Hoboken, 2003). Moore, J. and Ramamoorthy, S., Organic Chemicals in Natural Waters (New York, 1984). Ostroumov, S.A., Biologicheskie effekty pri vozdeistvii poverkhnostno-aktivnykh veshchestv na organizmy (Biological Effects of Surfactants on Organisms) (Moscow, 2001). Ostroumov, S.A., Zagryaznenie, samoochishchenie i vosstanovlenie vodnykh ekosistem (Pollution, Self-purification, and Restoration of Aquatic Ecosystems) (Moscow, 2005). Ostroumov, S.A., Biological Effects of Surfactants (Boca Raton, 2006). Parshikova, T.V., Effect of Surfactants in Growth, Reproduction, and Functional Activity of Algae in Cultures and Natural Populations, in Ekologo-fiziologicheskoe issledovanie vodoroslei i ikh znachenie dlya otsenki sostoyaniya prirodnykh vod (Ecologo-Physiological Investigation of Algae and their Significance for Estimation of the State of Natural Waters) (Yaroslavl, 1996). Ulanova, A.Yu. and Ostroumov, S.A., Use of Plants for Phytoremidiation and Investigation of Assimilatory Capacity of the Systems with macrophytes, in Vodnye ekosistemy i organizmy (Aquatic Ecosystems and organisms) (Moscow, 1999). Versteeg, D., Stanton, D., Pence, M., and Cowan, C., Effects of Surfactants on the Rotifer, Brachionus calyciflorus, in a Chronic Toxicity test and in the Development of QSARs, Environmental Toxicology and Chemistry 16 (5), 1051–1058 (2006). Wetzel, R., Limnology (San Diego, 2001).
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