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ISSN 0147 6874, Moscow University Soil Science Bulletin, 2011, Vol. ... concentration of polychlorinated biphenyls (PCB) in the soils of Moscow has been deter.
ISSN 01476874, Moscow University Soil Science Bulletin, 2011, Vol. 66, No. 1, pp. 36–41. © Allerton Press, Inc., 2011. Original Russian Text © G.I. Agapkina, E.S. Efimenko, E.S. Brodskiy, A.A. Shelepchikov, D.B. Feshin, 2011, published in Vestnik Moskovskogo Universiteta. Pochvovedenie, 2011, No. 1, pp. 39–45.

ECOLOGY

Concentration and Distribution of Polychlorinated Biphenyls in Soils of Moscow G. I. Agapkinaa, E. S. Efimenkoa, E. S. Brodskiyb, A. A. Shelepchikovb, and D. B. Feshinb a

Faculty of Soil, Moscow State University, Moscow, 119991 Russia; email: [email protected], [email protected] b Laboratory of Analytic Ecotoxicology, Severtsov Institute of Ecology and Evolution Problems, Russian Academy of Sciences, Leninskii pr. 33, Moscow, 119071 Russia; email: [email protected], [email protected], [email protected] Received October 20, 2010

Abstract—The concentration of polychlorinated biphenyls (PCB) in the soils of Moscow has been deter mined by gas chromatography and highresolution mass spectrometry (GCHRMS). The total concentra tions of 19 indicator and dioxinlike congeners, as well as PCBs in surface soils, are 2.85–60.62 µg/kg (the most contaminated sample was 4591.99 µg/kg). The average value, excluding the most contaminated sample, is 14.44 µg/kg, which is characteristic of residential areas of industrialized countries. This indicator varies insubstantially depending on the functional zone of the city. The toxicity equivalent of 12 dioxinlike PCBs in soils is 1.92 ng ITEQ/kg on average and varies in a range from 0.15 to 334.12 ng ITEQ/kg. The fraction of PCBs in the total toxicity of dioxins and dioxinlike compounds in soil varieties is 16.7–85.4%. Keywords: soil pollution, urban ecosystem, polychlorinated biphenyls, contribution to dioxin toxicity equiv alent DOI: 10.3103/S014768741101008X

Greenland, the northern regions of Sweden, the pre cipitation in the region of Saint Lawrence, and the bodies of penguins in Antarctica [5, 8]. The danger posed by PCBs for mammals and humans is connected with toxic activity such as car cinogenesis, mutagenesis, failure of reproductive functions and the immune system, and the negative impact on the liver and skin [5, 8, 14, 20, 27]. Among 209 congeners of PCBs with different numbers and positions of chlorine atoms in a molecule, 12 planar and monoorthosubstituted compounds were selected [6]. Their influence on the organism is recog nized as analogous to the influence of polychlorinated dibenzopdioxins and furans (PCDD/PCDF), which cause a failure of metabolism with the involve ment of nonspecific monooxygenases – cytochromes P450 [8]. Therefore, this group of PCBs is considered as a dioxinlike compound. Coefficients of toxicity (ITEF) for these congeners of PCBs and for PCDD/PCDF which allow the evaluation of equiva lent toxicity of the mixture of PCBs are applied using the following formula [6, 20]: ITEQPCB (ng ITEF/kg) = Σ(Ck ⋅ ITEFκ), where k is 1 of 12 congeners of PCBs and CPCB is its concentration. Generally, the determination of PCB concentra tion in the environment is limited to the determina tion of six or seven socalled indicator congeners with

Polychlorinated biphenyls (PCBs) are the most widespread ecotoxicants in the environment [5, 8]. According to the Stockholm Convention on Persistent Organic Pollutants, ratified in 2001, the production of PCBs should be prohibited, and the use of materials made on their basis will be stopped or restricted by 2025 [16]. Russia has also entered into this conven tion. A series of factors related to the unique properties of PCBs have facilitated their widespread distribution in the biosphere. The high chemical, thermal and bio logical stability and essential thermophysical and elec trical insulating features make these compounds useful as incombustible heatexchange and dielectric fluids in electronics; diffusion oils in pumps; components in paint, glue, and fireextinguishing liquids; plasticizers and compounds in plastics; and more [5, 8, 20]. The migration of PCBs along trophic chains and their glo bal spread in the biosphere are a consequence of these activities [25]. These lipophylic compounds actively accumulate in the adipose tissue of organisms. As a result, on territories polluted with PCBs, high levels of PCBs have been found in milk products, chicken eggs, and women’s breast milk [5, 6, 8, 20]. The accumula tion of these substances has also been observed in agri cultural plants [4]. Due to the intercontinental trans fer and high stability of PCBs, they are present in the components of ecosystems of baseline territories all across the world: in the soils and snow blanket of 36

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37

Table 1. Addresses of soil sampling for PCB determination on the territory of Moscow Probe number

Sampling location

Function of zone

1

Tret’ya Radialnaya ul. (tupik)

Park and recreation

2

Tagil’skaya ul., 10A

Industrial

3

Lavrushenskii per., 3/8

Residential

4

Tverskoi bul’v., 20

Residentialtransport

5

Varshavskoe sh., 622

Residential

6

Verkhnie Polya ul., promzona Kapotnya, 2

Industrial

7

Lermontovskii pr., 8

Residential

8

Karskovskaya ul., 129 and 129A

Reserve

9

Butlerov ul., Sevastopol’skii pr. (territory of Bitsevskii park)

Park and recreation

10

Yuzhnoe Butovo, B. Burovskaya ul., 9

Residential (School)

11

Kurkinskoe sh., 17

Park and recreation

12

Proektiruemyi proezd no. 712 (promzona Lyublino)

Industrial

13

Pererva ul., 300 m north of pond (promzona Lyublino)

14

Kalanchevskaya ul., 28 and 30

Reserve

15

MKAD, Naprudnaya ul., Perlovskoe cemetery

Cemetery

16

Solntsevo, Staroorlovskaya ul., 11

Residential

17

Borisovskii proezd, 38 and Orekhovii proezd, 37 build. 2

Residentialtransport

18

Yuzhnoe Butovo, Yuzhnobutovskaya ul., 62

Park and recreation

19

Ramenki, Vtoraya ul., 15 build. 2

Residential (School)

20

Mitinskaya ul., 37

Residential

21

Shenogina ul., 4

Park and recreation

22

Arkhitektor Vlasov ul., 20

23

Territory of Uzkoe park, Litovskii bul’v. and Novoyasenevskii pr. Crossroad

24

Olimpiyskii proezd, 21A

Residential (School)

25

Elektrodnaya ul., 9

Industrial

26

Eseninskii bul’v., 16

Residentialtransport

27

MKADzapad, flyover with Molodogvardeyskaya ul.

28

Podmoskovnaya ul., 5

Residential (School)

29

Pr. 40 let Oktyabraya and Sovkhoznaya ul. Crossroad

Park and recreation

30

Volgogradskii pr., 41

Industrial

31

Novokuznetskaya ul., 29/31, build. 1 and 2

Park and recreation

32

Akademik Millionshchikov ul., 11 and 13, build. 2

Residential

33

4th line of Khoroshevskoe sh. of Serebryanii bor, forest park

Park and recreation

34

Urzhumskaya ul., 1A

Industrial

35

Otradnaya ul., 1

Residential

36

Space between Novoterki and Kuskovskaya ul.

37

Profsoyuznaya ul., 86

38

Severnoe Butovo, Kulikovskaya and Starobitsevskaya ul. Crossroad

39

Yauzskii bul’v., 3

Residentialtransport

40

Solntsevo, DachnoMeshcherskii proezd, 2 (private property)

Residential

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Same

Same ''

Same

Same Park and recreation

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Table 2. Total concentration of PCBs in soils of Moscow, µg/kg Scale

Coefficient of variation, %

Median

60.62

57.77

92

10.96

5.12

60.62

55.49

116

9.91

2.89 13.30 3.86 2.85 9.03

40.38 20.63 58.99 28.66 19.83

37.48 7.34 55.14 25.81 –

83 19 124 83 –

11.34 19.37 7.76 15.74 –

Scale

Coefficient of variation, %

Median

City territory

Average

Minimum Maximum

City without object in Metrogorodok indus trial zone (n = 39) Industrial zone without object in Metrogoro dok industrial zone (n = 6) Residential zone (n = 9) Residentialtransport zone (n = 5) Park and recreational zone (n = 12) Yards of the kindergardens and school (n = 4) Reserve zone (n = 2)

14.44

2.85

18.22 13.54 17.81 12.13 15.75 14.43

Table 3. Total concentration of 12 dioxinlike compounds of PCB in soils of Moscow, ng ITEQ/kg City territory

Average

City without object in Metrogorodok indus trial zone (n = 39) Industrial zone without object in Metrogoro dok industrial zone (n = 6) Residential zone (n = 9) Residentialtransport zone (n = 5) Park and recreational zone (n = 12) Yards of the kindergartens and school (n = 4) Reserve zone (n = 2)

1.92

0.15

12.51

12.36

131

1.17

2.72

0.18

12.51

12.33

178

0.76

1.64 1.38 1.49 3.32 1.24

0.11 0.51 0.17 0.27 0.69

4.73 2.51 5.49 9.31 1.69

4.62 2.00 5.5 9.04 –

90 64 127 123 –

1.46 1.02 0.66 1.81 –

different degrees of chlorination and a maximal distri bution in technical mixtures. The provisions of the Stockholm Convention include a section devoted to the regulation and control of PCB concentration in the environment [6, 8, 16]. Soil plays a key role in both providing a protective function for other components of the system and act ing as a secondary source of pollution. However, the alteration of physical [18] and biological characteris tics [2, 18, 24] and the deterioration of the consumer properties of polluted production of animal husbandry and crops [4, 5, 8, 20] was observed at certain levels of PCB concentration. These events indicate the failure of ecological functions of soil and its degradation. Information on PCB pollution of surface soil in municipal areas where the ecological state directly influences the health and wellbeing of humans [14] is more interesting. Information in the literature regard ing this question is mostly concerned with the zone of influence zone of local sources of PCB production or their use as a raw material [7, 17] and is more limited in the case of large cities characterized by complicate infrastructures, numerous sources of pollution, and differentiated territory depending on functional pur pose [3, 7].

Minimum Maximum

The aim of this study is the determination of the concentration and distribution of PCBs in soils of dif ferent functional zones of Moscow and the evaluation of the ecological conditions of the city’s surface soil in connection with its pollution by these ecotoxicants. MATERIALS AND METHODS The soil samples were selected in the upper layer at a depth of 0–5 cm on the territory of the city in differ ent functional zones (Table 1). Additionally, the terri tories of kindergartens and schools were selected for increased attention in inhabited localities of Russia [15]. Soil varieties were represented by natural anthro pogenically changed surface soils (urban soils, mostly park and recreation zone), anthropogenically deeply transformed soils at the cultivated layer or grounds of different origin (urban grounds—industrial, residen tial, and residential–transport zone), and artificially created surfacehumified soillike creations (soil grounds and urban technological grounds) such as lawns in residential zones of newly erected buildings, as well as some parks and industrial zones [12]. An isomerspecific analysis for PCBs was carried out using highdefinition chromate–mass spectrome try after a preliminary multistage purification proce

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dure of samples from matrix components and concen tration [19]. Using internationally accepted practices, 19 congeners of PCBs were determined in soil objects: 12 dioxinlike (81, 77, 126, 169, 105, 114, 118, 123, 156, 157, 167, 189) and 7 indicator (28/31, 52, 101, 110, 153, 138, 180) which are specific for different types of technical mixtures of PCBs. RESULTS AND DISCUSSION Table 2 shows the statistical values of total concen tration of PCBs and Table 3 the 12 dioxinlike com pounds of PCBs for the entire territory of Moscow, as well for different functional zones of the city. The highest PCB concentrations (4591.99 μg/kg for total PCBs and 334.12 ng ITEQ/kg for the 12 dioxinlike PCBs) were identified in soils from the industrial zone of the Metrogorodok region (Eastern Administrative District) (Table 1, line 2). These are generally specific to the most polluted territories of specific industrial zones. More than 15 large industrial plants are located in this region and are involved with the production of construction materials and mechanical engineering (such as ZAO Cherkizovskiy zavod Mosmetrostroy, OAO Mospromzhelezobeton, OAO Mosmetromash, heat and power plant no. 23, GUP Khladoproduct, OOO VOSAT, and NPK Germetika). In connection with this, statistical data processing of PCB concen trations in soils of entire territory of the city and indus trial zone was carried out excluding the areas described above, yielding a more correct interpretation of data on PCB concentrations in the soil of the city. The total concentration of PCBs in the soil of the city (Table 2) was, on average, a few times higher than background levels evaluated on a global scale (Cav/Cmin/Cmax = 5.4/0.026/96.9 μg/kg) [25]. In com parison, the PCB concentrations in the soils of Europe brought about by cross border transfer vary in the range from 2 to 40 μg/kg [7, 23]. The concentration of PCBs in the soils of Moscow do not exceed and are sometimes even lower than the appropriate indicators for the soils in cities of Russia and Europe. The average value of PCB concentrations in the soil of St. Peters burg is 40 μg/kg, with concentrations of 5, 26, and 74 μg/kg in park and recreation, industrial, and resi dential zones of the city, respectively [3]. The total concentration of PCBs in the soils of Minsk varies from the lowest detectable values up to 7880 μg/kg [7]. The concentration of PCBs in the soils of Moscow for the entire city and for single functional zones varies within the wide range. The highest variation was observed in soils of industrial and park and recre ational zones. Literature data show a significant con centration of PCBs in soils of urban ecosystems, which is related to the great number of possible sources of pollution [7, 17, 26]. The average values of total concentration of 19 PCBs in the soils of different territories of the city are similar (Table 2). This fact probably can most likely be MOSCOW UNIVERSITY SOIL SCIENCE BULLETIN

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Table 4. Contribution of PCBs to dioxin toxicity equivalent Concentra Concentra Fraction of dioxin like PCBs in total tion tion Probe content of PCDD + of PCB, number of PCDD/F, ng ITEQ/kg ng ITEQ/kg PCDF + PCB, % 1 2 3 4 5 6 9 10 12 14 23 25 27 28 35 36 40

14.14 57.13 3.58 3.42 5.08 2.42 4.67 2.46 0.69 5.56 3.76 7.42 1.65 14.37 3.03 7.73 1.18

5.66 334.02 2.14 2.09 2.87 1.20 4.00 1.52 0.18 1.68 2.10 1.49 1.01 9.32 1.17 4.73 1.46

28.58 85.40 37.41 37.91 36.09 33.17 46.13 38.25 20.96 23.24 35.84 16.70 38.02 39.33 27.87 37.95 55.36

explained by the ease with which these compounds are spread regionally and globally as a result of atmo spheric transfer, which is specific to lowchlorinated congeners [8, 23, 25, 26]. At the same time, insubstan tial growth (by 1.5 times) of the average value of total PCB concentration in the soil can be seen in the fol lowing sequence: park and recreation zone < residen tial zone < reserve zone < yards of kindergartens and schools < residential and transport zone < industrial zone. A higher differentiation of functional zones than in the case of total PCB concentration was found during identification of the total concentration of 12 dioxin like PCBs (Table 3). The dioxin equivalent of 12 PCBs in soils increases (by about 2.7 times) in the following sequence of functional zones of the city: reserve zone < residential and transport zone < park and recreational zone < residential zone < industrial zone < yards of kin dergartens and schools. A similar sequence was found when determining the concentrations of polychlori nated dibenzopdioxins and furans (PCDD/PCDF) in the soils of Moscow [1], which supports the idea of similar supply sources of dioxins and dioxinlike PCBs to the city’s environment. The higher concentration of dioxinlike compounds in the yards of kindergartens and schools in comparison with other territories of the city deserves special attention (Table 3). The soil on the territories of these organizations is subject to prior ity sanitary control, and PCBs are included on the list of indicators for obligatory testing [15]. Vol. 66

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Table 5. Structure of PCB pollution of soils in Moscow 1 3

concentration when the sum of seven indicator PCBs (28, 52, 101, 118, 138, 153, 180) reaches 1000 μg/kg, where the soil irreversibly loses its natural ability for selfpurification from pollutants and requires remedi ation as a result [22]. According to the Dutch evalua tion system for the safety of soils polluted with PCBs, signs of disturbance of ecological function were found in 12.5% of soil objects on the city’s territory (Table 5). Values requiring soil remediation were noted only in the case of a single object from the industrial zone in Metrogorodok region (2.5% of tested soil objects) (Table 5). Criteria for evaluation of the pollution level requiring purification of the territory from PCBs have been approved by the Stockholm Convention [16] and the United States Environmental Protection Agency [21]: if the concentration of ecotoxicants in soils is higher than 50 and 500 μg/kg, respectively, then these substrates are equivalent to PCBcontaining materials and must disposed of. No soil objects on the territory of Moscow were found to exceed this level. CONCLUSIONS The total concentration of 19 congeners of PCBs in surface horizons of soil in Moscow varies in the range from 2.85 to 4591.99 μg/kg (with an average value of 14.44 μg/kg excluding the most polluted sample), which is characteristic of residential areas of industrial countries and varies insubstantially depending on the functional zone. The toxicity equivalent of 12 dioxinlike PCBs in soils of the city is, on average, 1.92 ng ITEQ/kg and varies within the range from 0.15 to 334.12 ng ITEQ/kg. The contribution of dioxinlike compounds in dif ferent soil varieties ranges from 16.7 to 85.4%. An analysis on the basis of European standards of ecologicalhygienic conditions of city soils for the presence of PCBs has revealed signs of its degradation in 12.5% of tested objects and the necessity of reculti vation measures in some industrial zones (2.5% of tested objects). REFERENCES 1. Agapkina, G.I., Brodskii, E.S., Shelepchikov, A.A., Feshin, D.B., and Efimenko, E.S., Polychlorinated DibenzopDioxins and dibenzofurans in Moscow

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