Biological effects of surfactants.pdf (science books)

TF4005 06 Chapter 1.fm Page 1 Friday, November 11, 2005 1:41 AM 1 Anthropogenic Impacts and Synthetic Surfactants as Pollutants of Aquatic Ecosystems 1.1 Criteria and Priorities in Assessing the Hazardous Impacts on Aquatic Biota The state of aquatic ecosystems reflects the general state of the biosphere. The situation in the biosphere affected by anthropogenic factors was characterized as “a slow explosion” (Fedorov 1987). The global change in the biosphere and climatic system of the Earth is a manifestation of this “slow explosion” (World Resources 1990–1991, Izrael et al. 1992). This change is due to man-made impact and disturbances in the aquatic and terrestrial ecosystems, which take part in the formation and regulation of biogeochemical and energetic fluxes in the biosphere (Fedorov 1987, 1992; Abakumov 1993; Kuznetsov 1993; Losev et al. 1993; Gorshkov 1987; Lovelock and Kump 1994; Lovelock 1995). The existing trends in increasing of anthropogenic changes in the ecosystems are unfavourable for preserving the biodiversity and form a dangerous basis for emergency and extraordinary situations (Izrael et al. 1992; Kondrasheva and Kobak 1996; Edgerton 1991; Gore 1992; Choucri 1993). The predicted events unfavourable for the aquatic and terrestrial ecosystems would occur within the lifetime of the current generation: the doubling of the concentration of CO2 in the atmosphere as compared with the preindustrial level would occur in the midor second third of the 21st century (Kondrasheva and Kobak 1996; World Resources 1990–1991; Edgerton 1991; Gore 1992; Choucri 1993), i.e., within the lifetimes of people who were born not long ago. The rate of increase of the CO2 level in the atmosphere does not slow down. The trends of anthropogenic changes hazardous for the biodiversity of hydrobionts (aquatic organisms) were analyzed in many publications (Fedorov 1974, 1977, 1980, 1992; Ostroumov 1981, 1984, 1986a,b, 1989; Yablokov and Ostroumov 1983, 1985; Yablokov and Ostroumov 1991; Venitsianov 1992; Khublaryan 1992; Shiklomanov 1992, Yakovlev et al. 1992; Losev et al. 1993; Moiseyenko 1999). In 1996, Russia passed the Concept of the Transition of the Russian Federation to Sustainable Development, which became a document to be taken into account by the Government in working out the programs for social and economical develop© 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 2 Friday, November 11, 2005 1:41 AM 2 S.A. OSTROUMOV ment, preparing the regulatory legal acts and making decisions (Decree of the President of the Russian Federation #440, 1996). The Concept was developed and raised to the rank of mandatory conceptual basis for decision making at the highest level in Russia mainly due to a new step in the development of the international community, which was the United Nations Conference on Environment and Development (Rio de Janeiro, 1992) and the program documents adopted by that conference. The Concept noted that “civilization, using a great variety of technologies destroying the ecosystems, did not in fact suggest anything that could substitute for the regulation mechanisms of the biosphere.” The importance of “the natural environmental biotic regulation mechanism” was emphasized. The ideas and suggestions put forward by experts (Venitsianov 1992; Khublaryan 1992; Fedorov 1992; Shiklomanov 1992; Yakovlev et al. 1992; Losev et al. 1993; Moiseyenko 1999) in the field of studies and preservation of aquatic ecosystems, which are water resources for this country, are in accord with this Concept. To optimize the relations between man and the biosphere, it is necessary to minimize the harmful impacts of chemical pollution on hydrobionts. “The insalubrity of pollutants with respect to man, particular agricultural organisms (plants and animals), and the biotic component of the ecosystem or biosphere as a whole could be considered the main property defining their ‘quality.’ In other words, the insalubrity is considered as a property of pollutants to cause undesirable, harmful, hazardous, or disastrous changes in the living organisms” (Fedorov 1980, p. 26). Analysis of the ecological hazard caused by pollution of the environment emphasized the danger of disturbing the balance of the ecological processes and the sustainability of the ecosystems (Fedorov 1992). The hazard of the water-polluting substances and xenobiotics as well as other details of the impact of chemical substances on hydrobionts and other organisms is analyzed in Stroganov (1976a,b; 1979; 1981), Patin (1979, 1997), Abakumov (1980), Lukyanenko (1983), Alabaster and Lloyd (1984), Izrael (1984), Filenko (1988), Flerov (1989), Malakhov and Medvedeva (1991), Bezel et al. (1994), Ostroumov (2002, 2004, 2005a,b), and others. Significant conceptual problems exist on the road leading towards progress in understanding the impacts of chemical substances on aquatic ecosystems (Ostroumov et al. 2003). The following principal problems are yet unsolved. What is the ecological hazard of a substance? Which aspects of the impacts of chemical substances on aquatic biota are the most important? How should the priorities among the diversity of biotic distortions caused by anthropogenic substances be systemized and ranked? It is not by chance that to date the Russian Federation has no generally recognized or certified methods to determine the ecological risk caused by chemical pollution (Krivolutsky 1994). In order to find systematic and ecologically based approaches, we developed a concept of the analysis of anthropogenic impacts on living nature in accordance with the levels of organization of living systems (Yablokov and Ostroumov 1983, 1985, 1991). The concept was supported by other authors (e.g., Lavrenko 1984; Gilyarov 1985). The main aspects of the problem include the necessity to analyze ecosystem consequences of the effect of xenobiotics on hydrobionts (Patin 1979; Fedorov 1980; Ostroumov 1984, 1986a, 2002, 2005a,b; Filenko 1988; Korte et al. 1997), the © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 3 Friday, November 11, 2005 1:41 AM BIOLOGICAL EFFECTS OF SURFACTANTS 3 expansion and improvement of the arsenal of biotesting methods (Filenko 1988; Flerov 1989), as well as the need for more detailed studies of the biological activities of some large groups of substances not sufficiently studied before, including synthetic surfactants. 1.2 Ecological Hazard and Ecosystem Consequences of the Effect of Anthropogenic Substances on Hydrobionts The system of assessing the environmental hazards of chemical substances in force in the European Union countries is based on three criteria: (1) acute toxicity (based on lethal concentrations (LC50)) for three groups of organisms (algae, daphnia, fish); (2) liability of substances to biodeterioration by microorganisms; and (3) ability of a substance to bioaccumulate (De Bruijn and Struijs 1997). A substance is considered to be low hazardous or not hazardous if it has a low toxicity (high LC50 values for the specified organisms), high ability of degradation (oxidation) by microorganisms, and if no bioaccumulation occurs or the bioaccumulation coefficient is smaller than 1000. While each of these criteria has its own merits, the very concept of hazard assessment based on this triad appears to be vulnerable to criticism from the hydrobiological point of view. Some of the critical comments are as follows: (1) the concept underestimates the possibility of a low value of LC50 for other organisms; (2) the capability of rapid degradation (oxidation) by microorganisms guarantees no ecological safety as the process of rapid oxidation of the chemical(s) is accompanied by rapid consumption of oxygen from water, which is fraught with hypoxia undesirable for the other oxygen-consuming hydrobionts; (3) bioaccumulation is not a necessary prerequisite for a negative impact to be manifested, as the substance can affect receptors of an organism, and this does not require its penetration into the tissues and cells of the organism. Thus, there is a need for further conceptual search for the approaches and priorities of estimating the hazards of substances for aquatic biota. The criteria based on which the hazardous impacts of anthropogenic substances on the ecosystems should be assessed have not been finally elaborated yet (Stroganov 1976a,b; Abakumov 1979, 1985; Yablokov and Ostroumov 1983, 1985; Filenko 1988; Krivolutsky and Pokarzhevsky 1990; Yablokov and Ostroumov 1991; Bezel et al. 1994; Krivolutsky 1994, Korte et al. 1997, Ostroumov et al. 2003, and others). Two groups of assessments of the states of ecological systems are distinguished (Fedorov 1980). The first group are integral indices, characterizing a result at the time of registration, such as biomass, number of species, and ratio of abundance, as well as various indices of species variety, diversity, relative abundance, domination, etc. (Fedorov 1980, p. 32). The second group are indices that can be expressed as a time derivative, i.e., as the rate of change of a function – such as productivity, respiration, and assimilation of substances (Fedorov 1980, p. 33). The answers to the problem of how to reveal, characterize and rank anthropogenic changes in ecosystems, especially under the influence of pollution, continue to be developed. Transition of a population or an ecosystem from one dynamical regime to another can be triggered by small changes in the anthropogenic impact on the © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 4 Friday, November 11, 2005 1:41 AM 4 S.A. OSTROUMOV population (Bolshakov et al. 1987). Some of the most notable and assessible ecosystem changes are used as indicators of disturbances in an aquatic ecosystem, and those hydrobionts that prove capable of revealing and assessing the ecosystemic disturbances act as indicator organisms (see, e.g., Vinberg et al. 1977; Abakumov 1983; Vetrov and Chugay 1988; Abakumov and Maksimov 1988; Abakumov and Sushchenya 1991; Budayeva 1991). Several systems of bioindicator organisms and hydrobiological methods were developed. The following methods and approaches are used to assess the state of aquatic ecosystems under increasing anthropogenic loads: systems using the Trent Biotic Index, Extended Biotic Index, the Verno and Taffy index, Chandler scores, Chatter biotic index, method of Pantle–Buck indicator organisms in Sládeþek modification, system of points of the U.K. Department for Environment, Food and Rural Affairs, Moller Pillot system, Abakumov–Maksimov system (see Vinberg et al. 1977; Abakumov 1983; Abakumov and Maksimov 1988; Abakumov and Sushchenya 1991; Budayeva 1991). The Woodiwiss system emphasizes the role of organisms related to indicator taxa. Such organisms are stoneflies, as well as some Oligochaeta and Chironomidae larvae. New approaches to assessing the anthropogenic impacts on ecosystems using benthic characteristics are likely to appear. The prospects of this are indicated by the revealed changes in Black Sea zoobenthos (Zaika 1992), changes in the structure of the White Sea microbenthos community (a decrease in the share of algophages, decreases in the Shannon index and Margalef index (Burkovsky et al. 1999) and changes in the trophic structures of zoobenthos of water bodies in Fennoscandia (Yakovlev 2000). A concept of ecological modifications was proposed to characterize anthropogenic changes in ecosystems such as alteration of the structure and metabolism of biocenoses (Abakumov 1987a, 1991; Izrael and Abakumov 1991; Ecological modifications… 1991). The following stages were proposed for the general characteristic of the state of ecosystems (Abakumov 1987a, 1991; Ecological modifications… 1991): (1) the state of ecological wellbeing; (2) the state of anthropogenic ecological stress; (3) elements of ecological regress; (4) the state of ecological regress; (5) the state of ecological and metabolic regress. These stages of the state of ecosystems were used in a number of publications to estimate the anthropogenic effects on ecosystems (e.g., Geletin et al. 1991; Izrael and Abakumov 1991; Zamolodchikov 1993). Situations are possible when anthropogenic effects (low pollution) can cause some ecological progress (sophistication of the biocenotic structure, increase in the number of species, complication of the trophic chain). Such situations were suggested to be designated as the state of anthropogenic excitation of the ecosystem (Abakumov 1991). In some cases the metabolic progress of biocenoses (increase in the biological activity of a biocenosis, i.e., the sum total of all processes of organic matter formation and degradation) is stimulated by progressing eutrophication of the water bodies under anthropogenic pollution (Abakumov 1991). Analysis of unique information on the results of hydrobiological monitoring at 635 sites in 378 water objects of the USSR in 1989 showed that 35% of all water bodies investigated were in the state of ecological regress (Abakumov 1991; Izrael and Abakumov 1991). © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 5 Friday, November 11, 2005 1:41 AM BIOLOGICAL EFFECTS OF SURFACTANTS 5 Assessing the ecological hazards of chemical substances, it is necessary to take into account many factors including different tolerances to anthropogenic factors of the populations of the same species, which are at certain stages of development (the term “lokhos” was suggested to denote specific stages of the development of populations (Abakumov 1972, 1985)), and different tolerances to the pollutants of different units of the temporal structures of biogeocenoses (Abakumov 1984). Elementary units of biocenotic temporal structure – phalanges – are distinguished (Abakumov 1973, 1985). In this relation we note that the concept of “seasonal complexes” of organisms was suggested and is being currently developed (Fedorov et al. 1982; Smirnov 1994). In Ostroumov (1981, 1984, 1986a,b), Yablokov and Ostroumov (1983, 1985, 1991), and Jablokov and Ostroumov (1991), anthropogenic effects were analyzed with respect to the organization levels of the living systems. The following levels were distinguished: molecular genetic level, ontogenetic level, population–species level, and biogeocenosis–biosphere level. Several aspects of the problem were emphasized in relation to the anthropogenic effects at the level of ecosystems and biocenoses. (We note that the order of listing is arbitrary; many aspects are not subject to a simplified classification being related to the anthropogenic effects at several levels of organization of the living systems.) The aspects are as follows: (1) changes in the structures of ecosystems/biocenoses, (2) disturbances of interspecies relations, (2.1) disturbances in trophic links and other biocenotic links, (2.2) disturbances in the balance between the species, (3) disturbances of ecological links resulting from broken information fluxes, (4) elimination of some types of biocenoses and vegetation as a whole, (5) transfer of substances by trophic chains and bioaccumulation of pollutants, (6) transport of toxic substances by migrants, (7) changes in primary productivity, and (8) biotransformation of pollutants in biological systems (this problem is also simultaneously related to the sphere of anthropogenic effects at the molecular level). The latter issue is closely connected to self-purification in aquatic ecosystems considered in relation to the problems of anthropogenic impacts on hydrobionts in the papers by Fedorov and Ostroumov (1984), Ostroumov (1986a), Telitchenko and Ostroumov (1990), Jablokov and Ostroumov (1991), Yablokov and Ostroumov (1991), Ostroumov and Fedorov (1999), and others. The results, which additionally emphasize the importance of these issues, were obtained in studies of the actions of organotin compounds on mesocosms (Stroganov 1979; Filenko 1988) and in the analysis of the effect of some organic compounds on plankton in experimental reservoirs (Schauerte et al. 1982; Lay et al. 1985a,b; see also Korte et al. 1997). An imbalance between some groups of plankton was shown when 2,4,6-trichlorophenol (TCP) (Schauerte et al. 1982), benzene and 1,2,4-trichlorobenzene (Lay et al. 1985a,b) were introduced into the reservoirs, which emphasized the role of sublethal effects of pollutants. The tendencies of increasing interest to such characteristics of substances as low acute toxicity were noted by Korte and co-workers: “Before now, we considered only the ecological and chemical properties of agrochemical products such as their stability to the effect of biotic and abiotic processes of transformation and degradation against the background of the production and application of these products. Now, © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 6 Friday, November 11, 2005 1:41 AM 6 S.A. OSTROUMOV ever greater attention would be paid to such ecotoxicological characteristics as low acute toxicity and mandatory exclusion of harmful impact on the useful organisms” (Korte et al. 1997; translated from the Russian edition). Our experimental work revealed noticeable effects of synthetic surfactants on water filtration by bivalve mollusks (Ostroumov et al. 1997a,b; 1998; Ostroumov and Donkin 1997), which is important in view of the significant contribution of water filtration by hydrobionts to the processes of self-purification in aquatic ecosystems (e.g., Konstantinov 1979). Other hydrobionts also play a significant role in selfpurification of water (e.g., Konstantinov 1979; Ostroumov 1998, 2002, 2004; Ostroumov and Fedorov 1999). It is important to focus attention not only on the assertion that anthropogenic disturbances take place, but also on revealing the disturbed links that are especially important for maintaining a given ecosystem and preventing its further rapid degradation. A disturbance of water self-purification in an ecosystem caused by pollutants implies a threat of a positive feedback and unwinding the spiral of further disturbances and degradation of the ecosystem. A necessary stage on the way to understanding the ecosystemic effects and the ecological role of pollutants is accumulation of knowledge of the biological effects of these substances on particular species. 1.3 Biological Effects of Substances and the Need of Refining the Arsenal of Biotesting Methods Methodological issues of biotesting are important for assessing, predicting, and preventing the consequences of pollution of the hydrosphere (Abakumov et al. 1981; Braginsky et al. 1979, 1983, 1987; Izrael 1984; Krivolutsky 1988; Filenko 1989; Flerov 1989). An important role was played by the works of N.S. Stroganov (Stroganov 1976a,b, 1979, 1981, 1982) and of his scientific school (e.g., Filenko 1985, 1986, 1988, 1989, 1990; Filenko and Lazareva 1989; Filenko et al. 1989; Artyukhova et al. 1997a,b), and also of A.G. Dmitrieva (Dmitrieva 1976; Dmitrieva et al. 1989, 1996a,b), A.I. Putintsev, E.F Isakova, V.M. Korol, M.S. Krivenko, G.D. Lebedeva, V.I. Artyukhova (Artyukhova 1996); and other faculty of the Department of Hydrobiology, Moscow State University: L.V. Ilyash (Belevich et al. 1997), L.D. Gapochka (Gapochka 1983, 1999; Gapochka et al. 1978, 1980; Gapochka and Karaush 1980), S.E. Plekhanov (Plekhanov et al. 1997), V.I. Kapkov and others. The issues of biotesting were developed in relation to issues of environmental pollution by A.G. Gusev, L.A. Lesnikov, E.A. Veselov, S.A. Patin, A.N. Krainyukova, their co-workers and many other authors. The impacts of pollutants on hydrobionts were studied by the faculty of several departments of Moscow State University: V.A. Veselovsky and T.V. Veselova (e.g., Veselova et al. 1993; Dmitrieva et al. 1989), A.O. Kasumyan (Kasumyan 1997), S.V. Kotelevtsev (Kotelevtsev et al. 1986), D.N. Matorin (Matorin 1993; Matorin et al. 1989, 1990) and of other institutes: A.I. Archakov, Yu.G. Simakov (Simakov 1986), S.A. Sokolova; scientists at the Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences (e.g., Kratasyuk et al. 1996), and others. © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 7 Friday, November 11, 2005 1:41 AM BIOLOGICAL EFFECTS OF SURFACTANTS 7 The problems of assessing the biological activity of substances are related to many aspects of ecotoxicology (Dmitrieva 1976; Slepyan 1978; Lukyanenko 1983; Simakov 1986; Bocharov 1988; Bocharov et al. 1988; Bocharov and Prokofyev 1988; Rand and Petrocelli 1985; Maki and Bishop 1985; Juchelka and Snell 1995; Donkin et al. 1997; Ostroumov 2003a,b; and others), monitoring (e.g., Izrael 1984; Filippova et al. 1978; Pokarzhevsky 1985; Khristoforova 1989; Dmitrieva et al. 1996a; Klyuev 1996; Krivolutsky 1990; Hill et al. 1994; Kotelevtsev et al. 1994, 1997; Smaal and Widdows 1994), and self-purification of aquatic ecosystems (e.g, Gladyshev et al. 1996; Ostroumov 2004; and others). The work on biotesting of substances, analysis of the results and improvement of the methods was carried out in view of the preparation and regular update of the lists of maximum permissible concentrations and reference safe levels of impact, e.g., by M.Ya. Belousova, T.V. Avgul, N.S. Safronova, G.N. Krasovsky, Z.I. Zholdakova, T.G. Shlepnina (1987); The List of … (1995) (compilers: S.N. Anisova, S.A. Sokolova, T.V. Mineyeva, A.T. Lebedev, O.V. Polyakova, and I.V. Semenova). Alternative methods of biotesting were developed using plant objects (Ivanov 1974, 1982, 1992; Wang 1987; Davies 1991; Davies et al. 1991; Obroucheva 1992). It was noted that “possibly, a direct transfer of laboratory experiments on biotesting of environmental toxicity would not guarantee an error-free prediction of changes in a water body … Therefore, … it is useful … to carry out biotesting not only on the organismal level, but also on the level of model ecosystems.” Also, “a water body … is a complex system and a significant difficulty is to find the main components, which determine the behavior of the system, and their interrelations” (Stroganov et al. 1983a). In spite of the diversity of the existing methods of biotesting (Filenko 1988; Simakov 1986; Krainyukova 1988; Barenboim and Malenkov 1986; Kotelevtsev et al. 1986; Rand 1985; Rand and Petrocelli 1985; Leland and Kuwabara 1985; Maki and Bishop 1985; Nimmo 1985; Hill et al. 1994; Volkov et al. 1997), there is a pressing necessity for developing new methods of biotesting and refining the existing methods as well as intensification of the work on biotesting of synthetic chemical compounds, which is stipulated by the following. First, the objectives of biotesting are rather diverse, and no universal method of biotesting has been found yet. “Diverse organisms – bacteria, algae, higher plants, leeches, water fleas, mollusks, fish, etc. – are used as objects for biotesting … . Each of these objects deserves attention and has its own advantages, but none of the organisms could serve a universal object equally applicable for different goals” (Filenko 1989). A similar opinion was voiced or, in fact, reasoned by other authors (e.g., Volkov et al. 1997). Second, work on biotesting new substances stays behind that of developing new chemical substances. According to the estimates by the National Institute of Environmental Health (U.S.) and National Toxicology Program (NTP), the level of knowledge of potential pollutants is absolutely insufficient and NTP “welcomes … suggestions on innovation methods for testing” (Rall 1991, Telitchenko and Ostroumov 1990). The total number of known and commercially produced chemical substances significantly exceeds the number of compounds studied using the biotesting techniques. As early as in 1990, the number of unique chemical substances © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 8 Friday, November 11, 2005 1:41 AM 8 S.A. OSTROUMOV in the Chemical Abstract Services computer catalogue exceeded 10 million (Rall 1991, Telitchenko and Ostroumov 1990). About 100,000 compounds are in commercial use (Barenboim and Malenkov 1986). Annually about 25,000 to 30,000 new substances are synthesized, and approximately 2,000 of them become widely used. Of the more than 100,000 compounds used, not more than 10% were subject to detailed toxicological and ecotoxicological tests and tests for carcinogenicity and mutagenicity. The hygienic norms developed on this basis exist even for a smaller number of substances. According to an estimate of the National Research Council of the National Academy of Sciences (U.S.), information on potential impacts of chemical substances on the most studied biological species – man – is available only for 20% of thousands of most common chemical substances (Rall 1991, Telitchenko and Ostroumov 1990). According to the data by the Organization for Economic Cooperation and Developments (OECD), only about half of the most mass-produced chemicals were subject to adequate toxicological assessment (OECD Press Release, Paris, April 9, 1990). The Environmental Protection Agency (U.S.) makes estimates of the ecological hazards of substances, but this work lags behind the preparation of new lists of substances that are planned for such assessments, and the list of substances to be tested has more than 13,000 entries (according to the Toxic Substances Control Act of 1976 (TSCA)). According to estimates, 5–10% of new substances put forward for ecological assessments would be recognized to be hazardous (Rosenbaum 1991). In a similar manner, determination of the biological activities of natural substances stays behind identification of new alkaloids, terpenes, flavonoids, glycosides, steroids, and other secondary metabolites in plants, invertebrates, fungal and microbial cultures. There is a certain dissatisfaction with the existing arsenal of methods for the assessment of chemicals. Criteria and requirements that the ideal or optimal set of methods for assessing the biological activity of substances should meet include the diversity of the objects, cost efficiency, operational efficiency, etc. (Alabaster and Lloyd 1984; Barenboim and Malenkov 1986; Filenko 1988). “The results of experiments [to determine the sublethal toxicity of pollutants, S.O.] should allow us to interpret them from the point of view of viability of particular species and ecosystems [italicized by the author, S.O.] … .” (Alabaster and Lloyd 1984). A justified requirement put forward here and in other publications (Patin 1988a,b,c; Filenko 1988; Bolshakov 1990; Bezel et al. 1994; Krivolutsky 1994) to interpret the results from the point of view of viability and functionality of ecosystems is not met in practice (Maki and Bishop 1985) and is not even analyzed in detail theoretically except in a comparatively minor number of works (Abakumov 1980; Bezel et al. 1994; Ostroumov 2003a). Here is a list of some important criteria to be taken into account in refining the methods for assessing the biological activities of substances (in arbitrary order, i.e., the order in the list is not related to their possible correlative importance). The list was prepared on the basis of the above-cited papers by various authors, and also of the experience of the author: (1) presentation of test organisms with different sensitivity (excessive sensitivity entails additional methodological difficulties; revealing low-sensitivity organisms is also useful as they can be used to develop purification © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 9 Friday, November 11, 2005 1:41 AM BIOLOGICAL EFFECTS OF SURFACTANTS 9 and bioremediation systems), (2) sufficient operational efficiency, (3) cost efficiency, (4) representation of all major trophic levels and ecological groups of organisms, (5) representation of parameters important for the ecosystem – including those that characterize its capability of self-purification, (6) representation of alternative methods of biotesting requiring no mammals or vertebrates; for humanitarian reasons, such methods should be used as much as possible, and (7) convenience of statistical processing of the data. We emphasize the importance of methods that are characterized by high operational efficiency, i.e., provide information in a short time. This property is especially important when information gathering on the biological activities and toxicities of substances lags behind their finding and synthesis of new chemicals. Evidently, one should not expect that a single test would satisfy all requirements at once. It seems expedient to focus on a set of several tests (Filenko 1988, 1989; Kotelevtsev et al. 1986; Krainyukova 1988; Hill et al. 1994; Volkov et al. 1997). Investigators should try to refine and expand the set of tests already in their arsenals. 1.4 Substantiating the Need for Further Research into Biological Effects of Synthetic Surfactants One of the most important and large classes of substances, whose biological effects were studied by many authors but were not characterized well enough for clear conclusions about the degree of their hazardous properties to be made, are synthetic surfactants. These surfactants are the most important components of commercial detergents. There is no consensus of opinion in the literature about the degree of ecological hazard of synthetic surfactants. On the one hand, there are many publications on different biological effects and disturbances in the structure and function of organisms under the influence of synthetic surfactants (e.g., Ganitkevich 1975; Denisenko and Rudi 1975; Komarovsky 1975; Shevchuk et al. 1975; Yusfina and Leontyeva 1975; Mozhayev 1976; Braginsky et al. 1979, 1980, 1983; Yanysheva et al. 1982; Gapochka 1983, 1999; Gapochka et al. 1978, 1980; Gapochka and Karaush 1980; Pashchenko and Kasumyan 1984; Khanislamova et al. 1988; Parshikova 1990, 1996; Parshikova et al. 1994; Lenova and Stupina 1990; Sirenko 1991; Khristoforova et al. 1996; Davydov et al. 1997; Vives-Rego et al. 1986; Versteeg et al. 1997a,b; Ostroumov 2003a,b, and a series of our other works published from the mid-1980s). Some papers about the effects of synthetic surfactants are mentioned below in this chapter and in the references (Metelev et al. 1971; Koskova and Kozlovskaya 1979; Patin 1979; Sivak et al. 1982; Malyarevskaya and Karasina 1983; Stavskaya et al. 1988; Lewis 1991a,b; Painter 1992) and in Chapters 3, 4 and 5. On the other hand, some of the authors do not include surfactants among the most important pollutants (Moore and Ramamoorthy 1984) and believe them to pose almost no ecological hazard for aquatic ecosystems (Fendinger et al. 1994). An experiment was described in which six volunteers received 100 mg of alkyl benzene sulfonate for four months. “Changes in their urine and body weight were analyzed © 2006 by Taylor & Francis Group, LLC TF4005 06 Chapter 1.fm Page 10 Friday, November 11, 2005 1:41 AM 10 S.A. OSTROUMOV but no harmful effect for their health was found” (Bakacs 1980). This experiment suggested a relative harmlessness of synthetic surfactants. The opinion that “synthetic surfactants can be assigned to the group of substances of relatively low toxicity and are not distinguished with pronounced cumulative properties” (Shtannikov and Antonova 1978) agrees with the statement that “from the ecotoxicological point of view, modern chemical means of oil spill control pose no serious threat for marine biota as the toxicity of most preparations is lower than that of oil (LC50 for major dispersants is usually 102–104 mg/l)” (Patin 1997). Oil emulsifier EPN-5 developed at the Institute of Oceanology, Russian Academy of Sciences at concentrations from 0.1 to 10 mg/l not only failed to inhibit the development of bacteria but, on the contrary, stimulated saprophytic bacteria. This preparation did not manifest any harmful action on other organisms, which also contributed to the view that synthetic surfactant-containing dispersants and emulsifiers are relatively harmless substances (Nesterova 1980). Seymour and Geyer are also certain that dispersants pose no ecological hazard and cause no damage to ecosystems (Seymour and Geyer 1992). An increase in the abundance of the saprotrophic group of microorganisms was demonstrated in the presence of dispersant DN-75 (5 mg to 10 g per liter). It was concluded that application of DN-75 is an effective means to stimulate self-purification of water bodies from oil pollution (Mochalova and Antonova 2000). Some reputable publications on environmental pollution by harmful substances do not mention synthetic surfactants at all. Thus, synthetic surfactants are absent in the subject index of the monograph Environmental Hazards: Toxic Waste and Hazardous Material (Miller and Miller 1991) though the entry “pesticides” is cited on 23 pages. In the second edition of W. Rosenbaum’s monograph “Environmental Politics and Policy,” which purports to be comprehensive (and is on the whole rather complete and comprehensive), a detailed subject index does not refer to surfactants and detergents, although pesticides are cited both in the index and in the text on at least 15 pages (Rosenbaum 1991). Neither synthetic surfactants nor detergents were mentioned in the subject indices of other reputable publications on environmental problems including chemical pollution: a three-volume Environmental Viewpoint (Lazzari 1994); a solid Global Accord published at the Massachusetts Institute of Technology (Choucri 1993); an important book on the policy in the field of environmental protection, Environmental Policy in the 1990s (Vig and Kraft 1994). Evidence of the insufficient knowledge of synthetic surfactants and relatively low attention to them is also presented by the fact that the number of publications on the ecological hazards and biological effects of these substances are much less than for the other groups of pollutants, e.g., pesticides and biocides studied in more detail (e.g., Stroganov 1979; Filenko and Parina 1983; Nimmo 1985; Ilyichev et al. 1985; Bogdashkina and Petrosyan 1988; Bocharov 1988; Bocharov et al. 1988; Bocharov and Prokofyev 1998; Widdows and Page 1993; Donkin et al. 1997), some other organic substances (Golubev et al. 1973; Klyuev 1996; Plekhanov 1997), and heavy metals (e.g., Filenko and Khobotyev 1976; Slepyan 1978; Leland and Kuwabara 1985, Beznosov et al. 1987; Chernenkova 1987; Marfenina 1988; Flerov et al. 1988; Khristoforova 1989; Malakhov and Medvedeva 1991; Artyukhova and Dmitrieva © 2006 by Taylor & Francis Group, LLC

Biological effects of surfactants

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