Chemosphere 93 (2013) 196–200

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Chemosphere

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Short Communication

Hazardous substances in the aquatic environment of Estonia

0045-6535/$ - see front matter � 2013 Elsevier Ltd. All rights reserved.http://dx.doi.org/10.1016/j.chemosphere.2013.05.036

⇑ Corresponding author at: Estonian Environmental Research Institute (underEstonian Environmental Research Centre), Tallinn, Estonia. Tel.: +372 6112964; fax:+372 6112901.

E-mail address: ott.roots@klab.ee (O. Roots).

Ott Roots a,b,⇑, Antti Roose c

a Estonian Environmental Research Institute (under Estonian Environmental Research Centre), Tallinn, Estoniab Estonian Marine Institute, University of Tartu, Estoniac Department of Geography, University of Tartu, Estonia

h i g h l i g h t s

� 130 Hazardous substances from 12 substances groups were investigated.� Higher concentrations were detected in the north-eastern Estonia.� Organotin compounds in sediments need further in-depth surveys.

a r t i c l e i n f o

Article history:Received 5 October 2012Received in revised form 8 May 2013Accepted 14 May 2013Available online 2 July 2013

Keywords:Hazardous substancesSurface waterWaste waterSewage sludgeBottom sedimentEstonia

a b s t r a c t

The Water Framework Directive (WFD) aims to regulate the management of European surface waterbodies. Directive 2008/105/EC, which establishes the environmental quality standards of priority sub-stances and certain other pollutants, the content of which in the surface water should be monitored,has been transposed by the Estonian Ministry of Environment 9 September 2010 Regulation No. 49.

Sampled hazardous substances were selected primarily based on their toxicity, as well as their lifetimein environment and ability to accumulate in living organisms (bioaccumulation). The contents of hazard-ous substances and their groups determined from Estonian surface waters remained below the limits ofquantifications of used analysis methods in most cases. However, the content of some heavy metals,mono- and dibasic phenols in the surface water/waste water and sewage sludge/bottom sediments canstill reach the delicate levels in the Estonian oil shale region in particular. Among new substances ana-lysed in Estonia historically first time in 2010, amounts of organotin compounds in sediments and somealkylphenols, their ethoxylates and phthalates were found in various sample matrices.

� 2013 Elsevier Ltd. All rights reserved.

1. Introduction

Upon selecting the hazardous substances, the lists of substanceshazardous to aquatic environment with the 21 July 2010 Regula-tion No. 32 ‘‘Lists 1 and 2 of substances and groups of substanceshazardous to the aquatic environment and lists of priority sub-stances, priority hazardous substances and their substance groups’’adopted by the Estonian Ministry of Environment was followed.Directive 2008/105/EC sets the environmental quality standardsof priority substances and other specified pollutants. The nationalmonitoring programme, setting the surface water monitoring,was transposed by the Estonian Ministry of Environment 9 Sep-tember 2010 Regulation No. 49. The programme covers 33 prioritysubstances of the WFD and in addition 16 hazardous substances orgroups of hazardous substances. Environmental monitoring is

regulated in Estonia by the Law on environmental monitoring,adopted by the Estonian Parliament January 20th, 1999.

The concentrations of hazardous substances were studied atdifferent sampling sites and matrices. 130 different substancesfrom 12 substances groups were investigated many of them forthe first time in the Estonia in 2010. Based on this recent surveythe aim of this paper is to examine the pollution by hazardous sub-stances in the aquatic environment in Estonia, to track and explorethe sources in order to elaborate targeted surveys and action-planfor the reduction of discharges or phasing out of hazardous sub-stances from the sources.

2. Materials and methods

For the selection of sampling matrices, three main criteria weretaken into account: solubility of substances in water; the bio-concentration factor (BCF) and the persistence of chemicals in theenvironment. Based on ‘‘Guidance on chemical monitoring of sedi-ment and biota under the WFD (Guidance Document No. 25, 2010)referred, optional and not recommended matrices were chosen.

O. Roots, A. Roose / Chemosphere 93 (2013) 196–200 197

Samples were taken from the surface waters, rivers, lakes and coast-al sea, and their bottom sediments as well as from the effluents andsewage sludge of waste water treatment plants and regions of Esto-nia with intensive agricultural activity (Roots and Nõmmsalu, 2011).Also, in order to examine the possible pollution sources of the BalticSea, sampling of hazardous substances in the waste water was con-ducted in different processing and industrial sites (Dydutyte et al.,2011). The Estonian Environmental Research Centre is accreditedin the field of water sampling by the Estonian Accreditation Centre.

2.1. Sampling surface water/waste water, sewage sludge and bottomsediments

The taking, storage and handling of effluent, surface water andsewage sludge samples was in accordance with the 6 May 2002Regulation of the Ministry of Environment No. 38 ‘‘Sampling Meth-ods’’. This Regulation is based on part 1 of standard EN 25667-1:1993 and parts 3, 4, 9, 10, 11, 13 and 15 of Estonian standardEVS-EN 5667. Standard EVS-EN 5667 is in compliance with therequirements of the respective ISO 5667 standard. Upon sampling,parts 1 and 2 EVS-EN 25667 (EVS-EN 25667-1:2005 and EVS-EN25667-2-2005) were taken into account (Dydutyte et al., 2011;Roots and Nõmmsalu, 2011).

The taking of samples from the bottom sediments was in accor-dance with the requirements of parts 1 and 2 of Estonian standardEVS-EN 25667 (EVS-EN 25667-1:2005 and EVS-EN 25667-2-2005)and parts 12, 15 and 19 of ISO 5667 standard (Dydutyte et al.,2011; Roots and Nõmmsalu, 2011).

2.2. Methods for chemical analyses

As the Estonian Environmental Research Centre or any othernational laboratory was not capable neither certified to analyse

Table 1Hazardous substances examined in the aquatic environment in the framework of Estonian

Hazardous substances NEMP1 1994–2013 NEMHeavy metals Phenols: 1-base and 2-base Volatile organic compounds, including chlorobenzenes Chlororganic pesticides Polyaromatic hydrocarbons Polychlorinated biphenyls Alkylphenols and their ethoxylates Organotin compounds

setalahthPPolybrominated diphenyls, diphenylethers, and polybrominated organic compounds Short- and medium chained chlorinated paraffins Perfluorinated compounds Plant protection products (except chlorinated pesticides) Pentachlorophenol Benzene Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxi-like polychlorinated biphenyls2

Oil (C10-C40) 1NEMP – National Environmental Monitoring Programme (Inland, marine and groundEstonian Environmental Research Centre capable to analyse since 2014.2National Food Monitoring Programme analysed by Baltic Sea fish and food (Roots and ZMinistry of Agriculture and the Veterinary and Food Board.

all listed substances in Estonia, some analyses were carried outat GALAB Laboratories in Germany. The laboratory proceedings,GALAB laboratories GmbH, Germany, and Estonian EnvironmentalResearch Centre, Estonia, followed the requirements of standardEN ISO/IEC 17025. For more detailed specification of methods, lim-its of quantifications (LOQ), limits of detection (LOD) and measure-ment uncertainty (MU%) are presented at Dydutyte et al. (2011);Roots and Nõmmsalu (2011). Commission Directive 2009/90/EClaying down technical specifications for chemical analysis andmonitoring of water status was adopted.

3. Results and discussion

The National Environmental Monitoring Programme of Estonia(NEMP), including the inland, marine and groundwater sub-pro-grammes was launched in 1994, receiving since then funding fromthe state budget. The state programme is upgraded and modifiedaccording to environmental legislation, state-of-art and currentneeds (Roose and Roots, 2005). However, NEMP does not embraceall water environments and substances, agricultural impacts, suchas pesticides in the intensive agricultural areas, waste water andsewage sludge are not surveyed in the framework of NEMP. Moni-toring and screening programmes are summarised in Table 1. Amap as Fig. 1 introduces the monitoring sites of BaltActHaz, ‘‘BalticActions for the Reduction of Pollution of the Baltic Sea from Hazard-ous Substances’’ project, screening in 2010. Summarising the re-sults since mid 1990s the content of some heavy metals, andmono- and dibasic phenols in surface waters exceeded the norma-tive levels, specifically in the Estonian oil shale region (Roots, 2008).

BaltActHaz project, aimed to carry out in-depth survey on theoccurrence of selected WFD, HELCOM priority substances andnationally important pollutants in the environment. Also, thesurvey tracked substances down to the sources in order to work

National Environmental Monitoring Programme (NEMP). (gray - implemented).

P 2014–

water sub-programmes of NEMP since1994 (Roots and Saare, 1996); substances

itko, 2004; Pandelova et al., 2008;Roots et al., 2008). Since 2002 commissioned by

Fig. 1. Sampling points of hazardous substances in Estonia.

198 O. Roots, A. Roose / Chemosphere 93 (2013) 196–200

further on the reduction of discharges or phasing-out (Dydutyteet al., 2011; Roots and Nõmmsalu, 2011; Roots and Leisk, 2012).Additional current information on hazardous substances from Bal-tActHaz allows the further refining state monitoring programmes,advancing the emission related control of hazardous substancesand to report confident information on hazardous substances tothe European Commission as well as to HELCOM (The HelsinkiCommission), for protecting marine environment). Survey pro-gramme of BaltActHaz, its spatial and temporal settings werebased on results of previous international and national surveys.The first screening carried out in the Tallinn metropolitan area in1999 (28 sites, mainly waste water plants), the second screeningfocused in north-eastern Estonia in 2000 (34 sites), third screeningcarried out in other Estonian counties in 2001 (42 sites). Monitor-ing of hazardous substances in the Baltic Sea in the framework ofHELCOM action plan has mainly been based on the measurementand assessment of contaminant concentrations in biota and sedi-ments (HELCOM, 2002).

Among recent surveys, the results and forecast of cross-European project on EU Wide Monitoring Survey of Polar PersistentPollutants in European River Waters, which summarized 122 watersamples from 27 countries on 35 selected polar persistent organiccompounds, were taken into account while programming the statemonitoring (Loos et al., 2008). The cleanest water samples werecollected from water bodies in Estonia, Lithuania and Sweden(Table 2).

The eight substances or substances groups (organitincompounds, brominated flame retardants (PBDE), perfluorinatedsubstances, phenolic substances (nonyl-phenols and their ethoxy-lates and octylphenols and their ethoxylates), chlorinated paraffins,and endosulfan) included in the study ‘‘Screening of Selected

Hazardous Substances in the Eastern Baltic Marine Environment’’(Lilja et al., 2009). Sampling sites of marine water and fish (herringand perch) are positioned near Sillamäe in eastern Gulf of Finland),western coast of Saaremaa island, coastal area in Pärnu Bay andcoastal area in western Gulf of Finland. Sampling sites in westernEstonia allow tracking trans-boundary air pollution carried bysouth-western winds (Roots, 1992; Gioia et al., 2007). In all ana-lysed water samples of hazardous substances, the concentrationswere below LOQ, except 4-nonylphenol (13–66 ng l�1). In case ofherring and perch, the LOQ was exceeded in few cases, tributyltinin Sillamäe site (accordingly 34.0 and 2.5 ng g�1 fresh weight) anddiphenyltin in perch from coastal areas in Pärnu Bay and westerncoast of Saaremaa island (accordingly 1.5 and 3.1 ng g�1 freshweight). Also, short and medium chain chlorinated paraffins wereexceeded the LOQ in some herring (21–49 ng g�1 fresh weight)and perch samples (3.9–15.0 ng g�1 fresh weight) and endosulphansulphate (0.01–0.08 ng g�1 fresh weight). From the brominatedflame retardants in fish muscle only some compounds BDE-47,BDE-99 and 100 in some fish muscle samples exceeded the LOQ con-centrations (Lilja et al., 2009). Compared to the other areas of theBaltic Sea, concentrations of hazardous substances sampled in theEstonian coastal area were lower (Lilja et al., 2009; HELCOM, 2010).

In the survey commissioned by the Ministry of the Environ-ment, the presence of 52 hazardous substances were studied in19 monitoring stations, including inland water bodies in the inten-sive agricultural area (Tamm, 2010). The survey identified residuecontent of AMPA (0.1–0.9 lg l�1) and glyphosate (0.05–0.3 lg l�1).Report emphasises that in some places isononyl-, and oktylphenolsand heavy metals Ni, Cd, Pb require more systematic monitoring.

In a comparison to listed surveys, the BaltActHaz projectextended the sampling of hazardous substances in terms of

Fig. 2. The content of heavy metals in river water.

O. Roots, A. Roose / Chemosphere 93 (2013) 196–200 199

geographical and chemical coverage. The hazardous substanceswere sampled at 8 waste water treatment plants, 2 monitoring sta-tions at Lake Peipsi, 11 rivers flowing into the Baltic Sea, 5 sitesalong coastal waters and regions with intensive agricultural area(Roots and Nõmmsalu, 2011). Also, the waters at industrial territo-ries were sampled (Dydutyte et al., 2011). The following hazardoussubstances and their groups of substances were identified: heavymetals, phenols, alkylphenols and their ethoxylates, polyaromatichydrocarbons, volatile organic compounds, organotin compounds,phthalates, polybrominated organic compounds, short and med-ium chain chlorinated paraffins, perfluoro-compounds, and pesti-cides (Roots and Nõmmsalu, 2011; Roots and Leisk, 2012). 130different substances from 12 substances groups were investigatedmany of which have been investigated for the first time in the Esto-nia and the Baltic States (Dydutyte et al., 2011).

The contents of monobasic (p-,m-,o-cresol,3,4-,3,5-,2,3-,2,6-dimethylphenol,phenol) and dibasic (resorcin,2,5-dimethylresor-cin,5-methylresorcin) phenols as potentially harmful in Estonianwater bodies were determined. Water samples were taken fromthe Rivers Narva, Kohtla, Keila and Vasalemma. High contents ofmonobasic phenols were determined in the surface water of RiversKohtla (11.5 lg l�1), Vasalemma (5.2 lg l�1), Narva (4.3 lg l�1) andKeila, (2.1 lg l�1), while the annual average value of the environ-mental quality standard for monobasic phenols is 1 lg l�1. Amongcresols, the contents of p- and m-cresols in the Rivers Keila andNarva were high, respectively 2.3 lg l�1 and 2.1 lg l�1. The con-tents of resorcins in the surface water of screened rivers remainedbelow the limit of quantification, the value of environmental qual-ity standard (10 lg l�1) established for dibasic phenols in sum(Roots and Nõmmsalu, 2011).

The contents of all alkylphenols and their ethoxylates in thewaters of rivers under the screening did not exceed the annualaverage values or the maximum allowable concentrations of envi-ronmental quality standards for inland surface waters. Two of allalkylphenols have environmental quality standards: 4-n-nonyl-phenol – annual average 0.3 lg l�1 and the maximum allowable2.0 lg l�1 and 4-tert-octylphenol – annual average 0.1 lg l�1

(Roots and Nõmmsalu, 2011).The contents of hazardous substances and their groups exam-

ined in surface waters, coastal waters and waste waters remainedbelow the limits of quantifications of employed analysis methodsin most cases. Environmental Quality Standards (EQS) for prioritysubstances and certain other pollutants (Directive 2008/105/EC)for inland surface waters and for other surface waters were fol-lowed. The content of heavy metals in all rivers under the screen-ing and Lake Peipus did not exceed the environmental qualitystandards established by Regulation No. 49 of 9 September 2010of the Minister of the Environment. The highest contents of lead– 0.65 lg l�1 (7.2 lg l�1) and nickel – 2.90 lg l�1 (20 lg l�1) werefound in the water of the Pühajõgi River, the highest contents ofzinc – 6.2 lg l�1 (10 lg l�1) and 5.6 lg l�1 were found, respectively,in the water of the Vasalemma and the Pärnu Rivers and the high-est content of copper – 10.3 lg l�1 (15 lg l�1) and 9.6 lg l�1 werefound in the water, respectively, the Vasalemma and the MustajõgiRivers (Fig. 2). The brackets contain the respective annual averagevalue of the environmental quality standard in inland surfacewaters which were not exceeded. The maximum allowable con-centrations have not been established for the contents of theseheavy metals. The contents of chromium exceeded the limit ofquantification (0.1 lg l�1) in the waters of the Pärnu and Vasalem-ma Rivers, respectively 0.81 lg l�1 and 0.57 lg l�1. The annualaverage value of the environmental quality standard for chromiumin inland surface waters is 5 lg l�1. The contents of mercury in allwater samples taken from the rivers remained below the limit ofquantification (0.05 lg l�1) (Roots and Nõmmsalu, 2011).

Organotin compounds were surveyed in the waters of Narva,Keila and Kasari Rivers, the LOQ was exceeded by the concentra-tion of mono- (0.0019–0.0054 lg l�1) and dibutyltin (0.0013–0.0015 lg l�1) in those rivers. At the same time the concentrationsof organotin compounds in the surface water sediments of all 11rivers remained below the limit of quantification of the used ana-lytical method (Roots and Nõmmsalu, 2011). The concentrations oforganotin compounds in the waste water of the Tallinn and Keilawaste water treatment plants detected in the course of screeningindicate that only LOQ concentration was exceeded by themonobutyltin in Keila WWTP (0.008 lg l�1) (Roots and Nõmmsalu,2011). However, organotin compounds is a environmental issue inthe coastal sea near ports and docks. The high contents of organo-tin compounds were found in the water samples taken from theeffluents of Baltic Ship Repair Company and Company Baltic Pre-mator and which flow into Tallinn Bay (MBT – 614 ng l�1; DBT –7058 ng l�1;TBT – 9090 ng l�1; monophenyltin – 51 ng l�1; anddiphenyltin – 25 ng l�1). The contents of organotin compounds inthe the sewage sludge of Baltic Premator Company were foundas follows: MBT – 152 lg kg�1 DM, DBT – 150 lg kg�1 DM,TBT –22,500 lg kg�1 Dm, tetrabutyltin – 27 lg kg�1 DM, monophenyltin– 59 lg kg�1 DM, diphenyltin – 34 lg kg�1 DM and triphenyltin –15 lg kg�1 DM.

The content of active ingredients of 23 plant protection productsin the samples taken from the inland water bodies situated in 8 re-gions of Estonia with intensive agricultural activity remained all be-low the LOQ confirming the good status of inland water bodies inEstonia (Dydutyte et al., 2011; Roots and Nõmmsalu, 2011).

In the case of the sewage sludge as waste, its recycling, leadingit back to the soil should be considered. All organic contaminantsare not regulated, as well as for example tin and all organotin com-pounds among heavy metals, which is often detected in remark-able quantities in sewage sludge. According to legislation, thesediment, consisting heavy metals, can be outspread in the fieldor used in greenery planting under certain circumstances. On theother hand, the large quantities of the other hazardous contami-nants in the sediments, identified in the course of screening indi-cate that the regulation on requirements for using sewage sludgein agriculture, landscaping and recultivation should amended byadding limit values for additional hazardous substances.

4. Summary

The results confirm that the status of hazardous substances insurface waters in Estonia can be stated as good. However, the rou-tine surveys of mono- and dibasic phenols and heavy metals in thewater, sediments and coastal marine fish (for heavy metals) shouldcontinue. In addition, as a new substances, organotin compounds

Table 2Content of some priority substances and certain other pollutants in Estonia‘s rivers and comparison with other European Union rivers, maximum content and average content(Loos et al., 2008).

Priority substance Unit Emajõgi river Purtse river(oil shale region)

Narva river(oil shale region)

Maximum contentin EU rivers

Average contentin EU rivers

LOD limit ofdetection

Diuron ng l�1 2 0 2 864 41 1Simazine ng l�1 0 0 0 169 10 1Isoproturon ng l�1 0 0 0 1959 52 1Atrazine ng l�1 0 0 0 46 3 1Nonylphenol ng l�1 0 0 0 4489 134 504-tert-Octylphenol ng l�1 0 0 0 557 13 10Perfluoro-octanoic acid ng l�1 1 1 0 174 12 1Perfluoro-octanoic sulphonate ng l�1 1 0 1 1374 39 1

200 O. Roots, A. Roose / Chemosphere 93 (2013) 196–200

should be monitored within the state monitoring programme. Inthe framework of enterprise monitoring organotin compoundsshould be quantified in the port areas of the coastal sea wherethe high concentrations of organotin compounds, especiallymono-, di- and tributyltin were detected in the course of screening.Biota monitoring according to HELCOM bioindicators, the Balticherring in offshore and the perch in estuary is proposed for inclu-sion in the monitoring programme. 4-tert-octylphenol, 4-tert-butylphenol, 4-tert-penthylphenol-, di-2-ethoxyethyl-phtalate,dimethylpthalate, diisobutylphthalate, di(2-ethylhexyl) phthalateand dimethylphthalate should be randomly monitored once everytwo or three years in 7 rivers of the 11 surveyed (the Rivers Kohtla,Kunda, Vääna, Jägala, Vasalemma, Kasari and Pärnu) (Roots andLeisk, 2012). The special attention should be paid to river Vasalem-ma as it belongs among others to the salmon rivers under the nat-ure protection. The phthalates should be sampled as well in wastewaters at sewage plants. Dibutylphthalate and diisononylphthalatewere detected in the sewage sludge. As the regulation on using thesewage sludge in agriculture, landscaping and re-cultivation isoutdated, which sets the limit value only for the concentration ofseven heavy metals in the waste water sediment (cadmium, cop-per, nickel, lead, zinc, mercury and chromium), the regulation needurgent amendment in the nearest future.

Obtained information on hazardous substances facilitates thefurther enhancement of the state monitoring programme and theemissions control of hazardous substances in Estonia and thecoastal Baltic Sea. The output of activities should be the removalof selected WFD, HELCOM priority substances and nationally shortlisted pollutants, from the sources and the bringing of substanceswith natural origins to concentrations near the natural backgroundlevel in aquatic environment. Continuing refining monitoring pro-gramme and the assessment of implementation action plans sup-ports achieving the good chemical status of surface water by 2015.

Acknowledgements

The study was supported by the Ministry of the Environment ofEstonia, Ministry of Agriculture and Veterinary and Food Agency,LIFE07ENV/EE/000122 ‘‘Baltic Actions for Reduction of Pollutionof the Baltic Sea from Priority Hazardous Substances – BaltActHaz’’Project, the research funding SF0180052s07, IUT2-17 and ETF7459of the Estonian Research Council.

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