Organic Pollutants

Front matter

Organic Pollutants Monitoring, Risk and Treatment Edited by M. Nageeb Rashed Edited by M. Nageeb Rashed Organic pollutants cause several environmental problems if discharged to air or water body. The occurrence of organic pollutants in the ecosystem, their risk and removal methods are very important issues .This book deals with several aspects of organic pollutants, especially in the light of organic pollutants monitoring, risk assessment as well as the practical application of different techniques for removing it from the environment. The book is divided into three sections contains 9 chapters. The first section explains monitoring of organic pollutants in soil and water. The second section discusse its risk to human, soil and plants. The third section focuse on the different treatment process for the removal of organic pollutants.

Photo by aga7ta / iStock ISBN 978-953-51-0948-8 Organic Pollutants - Monitoring, Risk and Treatment

ORGANIC POLLUTANTS - MONITORING, RISK AND TREATMENT Edited by M. Nageeb Rashed

Section 1 Monitoring Section 1 Monitoring

Chapter 1 The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic Radim Vácha, Jan Skála, Jarmila Čechmánková and Viera Horváthová Additional information is available at the end of the chapter http://dx.doi.org/10.5772/ 53332 1. Introduction The Czech Republic belongs to the countries with long-term industrial history. The environ‐ mental load by persistent organic pollutants pollution has been proved to follow the indus‐ trial development, especially concerning the polycyclic aromatic hydrocarbons emissions. In the Czech Republic the industrial growth started during 19th century and in the beginning of 20th century at the time of the Austro-Hungarian Monarchy. The industrial development continued after the Monarchy collapse and the Czechoslovak Republic formation (1918 - 1938). The rapid industry growth was led by heavy industry priority in the period of social‐ istic economy (1948 – 1990) and caused the wide environmental damages. The imission outputs reached maximum in 70 th years when the daily average concentrations of SO 2 (gaseous emission) were over 50 μg/m3 and in the coalfield areas of North Bohemia up to 70 - 100μg/m3 following the data of Czech Hydrometeorological Institute [ 1]. The loading by floating dust particles was more than 70 - 100μg/m3 and in extreme cases reached 150μg/m3. There are two main coal mining regions in the Czech Republic (see Figure 1.). The history of brown coal mining started in North Bohemian Region in the beginning of 19 th century (1819) and reached the maximum in the eighties of 20th century. The history of black coal mining in North Moravian Region is very similar and the mining activity peaked in the eighties of 20 th century (about 20 millions tons per year). Opencast coal-mining activity in North Bohemia has been changing the landscape character in more intense way, however the deep mines in North Moravia has also caused environmental damages due to terrain subsidence and la‐ goons with coal powder and waste. Other important risk are linked to the combustion of brown coal of low quality with increased contents of sulphur and arsenic [ 2] in coal-fired power stations in North Bohemia and to the presence of metallurgical industry in the North © 2013 Vácha et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Vácha et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Chapter 1 The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic Radim Vácha, Jan Skála, Jarmila Čechmánková and Viera Horváthová Additional information is available at the end of the chapter http://dx.doi.org/10.5772/ 53332 1. Introduction The Czech Republic belongs to the countries with long-term industrial history. The environ‐ mental load by persistent organic pollutants pollution has been proved to follow the indus‐ trial development, especially concerning the polycyclic aromatic hydrocarbons emissions. In the Czech Republic the industrial growth started during 19th century and in the beginning of 20th century at the time of the Austro-Hungarian Monarchy. The industrial development continued after the Monarchy collapse and the Czechoslovak Republic formation (1918 - 1938). The rapid industry growth was led by heavy industry priority in the period of social‐ istic economy (1948 – 1990) and caused the wide environmental damages. The imission outputs reached maximum in 70 th years when the daily average concentrations of SO 2 (gaseous emission) were over 50 μg/m3 and in the coalfield areas of North Bohemia up to 70 - 100μg/m3 following the data of Czech Hydrometeorological Institute [ 1]. The loading by floating dust particles was more than 70 - 100μg/m3 and in extreme cases reached 150μg/m3. There are two main coal mining regions in the Czech Republic (see Figure 1.). The history of brown coal mining started in North Bohemian Region in the beginning of 19 th century (1819) and reached the maximum in the eighties of 20th century. The history of black coal mining in North Moravian Region is very similar and the mining activity peaked in the eighties of 20 th century (about 20 millions tons per year). Opencast coal-mining activity in North Bohemia has been changing the landscape character in more intense way, however the deep mines in North Moravia has also caused environmental damages due to terrain subsidence and la‐ goons with coal powder and waste. Other important risk are linked to the combustion of brown coal of low quality with increased contents of sulphur and arsenic [ 2] in coal-fired power stations in North Bohemia and to the presence of metallurgical industry in the North © 2013 Vácha et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Vácha et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Moravian region. The load of both areas by risky elements and persistent organic pollutants gave them the designation of imission regions. The North Bohemian region covers the area of 5 districts (Decin, Teplice, Usti nad Labem, Most and Chomutov and neighbouring dis‐ tricts in the West Bohemian region where increased load still remains). The region is spread along the Czech-German border shaped by the Ore Mountains. The North Bohemian basin is delimitated by the dislocation at the foothill of the Ore Mountains. The North Moravian region situated close to Czech-Polish border covers the area of 3 districts (Ostrava, Karvina, Frydek-Mistek). The flat character of the landscape in west part of the region (Karvina, Os‐ trava) passes to mountainous area forming the Czech-Slovak borderland (the Moravsko‐ slezske Beskydy Mountains). The load of environment in both regions is historically increased with the historical pollution peak in seventies and eighties of 20 th century when high content of emission-out puts in the air connected with acid rains led to perceptible damages of the environment (especially damage of the spruce forest in the Ore Mountains). The situation started to change after 1990 thanks to industrial production decrease and the necessity of technology improvement of coal-fired power stations (the installation of effi‐ cient dust particles filters in the beginning of the 21 st century). The modernization of four coal-fired power stations situated in the North Bohemian region (Ledvice, Pocerady, Tusi‐ mice and Prunerov) has been approaching in two periods. In the 1 st period (1996 – 1999) there were radically decreased the emission out puts in following extent: SOx -92%, NOx -50%, CO -77% and solid polluting particles -93%. The next period of modernization is run‐ ning and will be finished till 2020 following precise schedule of the works. The next decrease of emission out puts will be reached in the following extent: SOx -57%, NOx -59%, CO 2 -31% and solid polluting particles -39%, data from [3].

The comfortless situation remains in the North Moravian region and increased contents of emission out-puts in the air are the theme of many professional and public discussions [ 4,5]. The special attention is paid to increased content of polycyclic aromatic hydrocarbons in en‐ vironment which is connected with increased number of some inhabitant’s diseases in the region [3]. The load stemmes from emission out puts from heavy industrial factories (for ex‐ ample the Trinec and Ostrava ironworks factories etc). There is one coal-fired power station (Detmarovice) in the region where black coal is used. The mountainous area situated in east‐ ern part of the region serve for recreation and sport and there are no important sources of pollution. Nevertheless the increased pollution was proved in the mountains are due to imission out puts from western part of the region. Other environmental hazards in the re‐ gion are linked to the existence of lagoons where around 300,000 tons of petroleum sludge have been deposited. The recent dredge and liquidation of sludge meets some technical and economical inconveniences.

The soil is one of the important environmental sinks of pollution and soil contamination can reflect long-term load by dry and wet depositions. Increased soil load by risky substances poses serious threats to environment, plant production and food security. The maintenance of suitable state of soil load by risky substances should be an interest of every society. The evaluation of soil load by risky substances must be supported by the knowledge of risky substances background values, their inputs into soils, their behaviour and fate in the soil en‐ Organic Pollutants - Monitoring, Risk and Treatment4 vironment, their transfer into the plants etc. The approaches to limit values system are not unified across the world, nor in European context and different philosophies may be used for the evaluation of soil contamination. There has been paid longterm attention to soil con‐ tamination issue in the Czech Republic. The potentially toxic compounds observed in Czech agricultural soils can be separated into two main groups of pollutants: • Inorganic pollutants - potentially risky elements (REs), As, Be, Cd, Co, Cr, Hg, Cu, Mn, Ni, Pb, V, Zn, respectively Se and Tl • Organic pollutants – persistent organic pollutants (POPs), A wide group of different or‐ ganic substances, with linear or cyclic character. The current list of POPs observed in Czech legislation (Soil Protection Act) includes monocyclic and polycyclic hydrocarbons, PCBs, sum of DDT and petroleum hydrocarbons (table 1).

POPs Monocyclic aromatic hydrocarbons benzene, toluene, xylene, ethylbenzene Polycyclic aromatic hydrocarbons naphtalene, anthracene, pyrene, phluoranthene, phenanthrene, chrysen, benzo(b)phluoranthene, benzo(k)phluoranthene, benzo(a)anthracene, benzo(a)pyrene, indeno(c,d)pyrene, benzo(ghi)perylene chlorinated hydrocarbons PCB(28+52+101+118 +138+153+180), HCB, α-HCH, β-HCH, γ-HCH Pesticides DDT, DDD, DDE Others styrene, petroleum hydrocarbons PCDF 2,3,7,8 TeCDF, 1,2,3,7,8 PeCDF, 2,3,4,7,8 PeCDF, 1,2,3,4,7,8 HxCDF, 1,2,3,6,7,8 HxCDF, 1,2,3,7,8,9 HxCDF, 2,3,4,6,7,8 HxCDF, 1,2,3,4,6,7,8 HpCDF, 1,2,3,4,7,8,9 HpCDF, OCDF PCB 189, PCB 170, PCB 180 PCDD 2,3,7,8 TeCDD, 1,2,3,7,8 PeCDD, 1,2,3,4,7,8 HxCDD, 1,2,3,6,7,8 HxCDD, 1,2,3,7,8,9 HxCDD, 1,2,3,4,6,7,8 HpCDD,OCDD Table 1. Persistent organic pollutants observed in Czech agricultural soils The system of limit values of soil contamination must accept sources of risky substances that influence the behaviour of risky substances in the soil (mobility, bioavailability). POPs can originate from: • Natural sources - volcanic activity (REs, POPs), natural fires (POPs) etc. • Anthropogenic sources – like industrial activities, transport emissions, the use of agro‐ chemicals and biosolids in agriculture, waste water production etc. The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic http://dx.doi.org/10.5772/ 53332

Moravian region. The load of both areas by risky elements and persistent organic pollutants gave them the designation of imission regions. The North Bohemian region covers the area of 5 districts (Decin, Teplice, Usti nad Labem, Most and Chomutov and neighbouring dis‐ tricts in the West Bohemian region where increased load still remains). The region is spread along the Czech-German border shaped by the Ore Mountains. The North Bohemian basin is delimitated by the dislocation at the foothill of the Ore Mountains. The North Moravian region situated close to Czech-Polish border covers the area of 3 districts (Ostrava, Karvina, Frydek-Mistek). The flat character of the landscape in west part of the region (Karvina, Os‐ trava) passes to mountainous area forming the Czech-Slovak borderland (the Moravsko‐ slezske Beskydy Mountains). The load of environment in both regions is historically increased with the historical pollution peak in seventies and eighties of 20 th century when high content of emission-out puts in the air connected with acid rains led to perceptible damages of the environment (especially damage of the spruce forest in the Ore Mountains). The situation started to change after 1990 thanks to industrial production decrease and the necessity of technology improvement of coal-fired power stations (the installation of effi‐ cient dust particles filters in the beginning of the 21 st century). The modernization of four coal-fired power stations situated in the North Bohemian region (Ledvice, Pocerady, Tusi‐ mice and Prunerov) has been approaching in two periods. In the 1 st period (1996 – 1999) there were radically decreased the emission out puts in following extent: SOx -92%, NOx -50%, CO -77% and solid polluting particles -93%. The next period of modernization is run‐ ning and will be finished till 2020 following precise schedule of the works. The next decrease of emission out puts will be reached in the following extent: SOx -57%, NOx -59%, CO 2 -31% and solid polluting particles -39%, data from [3].

The comfortless situation remains in the North Moravian region and increased contents of emission out-puts in the air are the theme of many professional and public discussions [ 4,5]. The special attention is paid to increased content of polycyclic aromatic hydrocarbons in en‐ vironment which is connected with increased number of some inhabitant’s diseases in the region [3]. The load stemmes from emission out puts from heavy industrial factories (for ex‐ ample the Trinec and Ostrava ironworks factories etc). There is one coal-fired power station (Detmarovice) in the region where black coal is used. The mountainous area situated in east‐ ern part of the region serve for recreation and sport and there are no important sources of pollution. Nevertheless the increased pollution was proved in the mountains are due to imission out puts from western part of the region. Other environmental hazards in the re‐ gion are linked to the existence of lagoons where around 300,000 tons of petroleum sludge have been deposited. The recent dredge and liquidation of sludge meets some technical and economical inconveniences.

The soil is one of the important environmental sinks of pollution and soil contamination can reflect long-term load by dry and wet depositions. Increased soil load by risky substances poses serious threats to environment, plant production and food security. The maintenance of suitable state of soil load by risky substances should be an interest of every society. The evaluation of soil load by risky substances must be supported by the knowledge of risky substances background values, their inputs into soils, their behaviour and fate in the soil en‐ Organic Pollutants - Monitoring, Risk and Treatment4 vironment, their transfer into the plants etc. The approaches to limit values system are not unified across the world, nor in European context and different philosophies may be used for the evaluation of soil contamination. There has been paid longterm attention to soil con‐ tamination issue in the Czech Republic. The potentially toxic compounds observed in Czech agricultural soils can be separated into two main groups of pollutants: • Inorganic pollutants - potentially risky elements (REs), As, Be, Cd, Co, Cr, Hg, Cu, Mn, Ni, Pb, V, Zn, respectively Se and Tl • Organic pollutants – persistent organic pollutants (POPs), A wide group of different or‐ ganic substances, with linear or cyclic character. The current list of POPs observed in Czech legislation (Soil Protection Act) includes monocyclic and polycyclic hydrocarbons, PCBs, sum of DDT and petroleum hydrocarbons (table 1).

POPs Monocyclic aromatic hydrocarbons benzene, toluene, xylene, ethylbenzene Polycyclic aromatic hydrocarbons naphtalene, anthracene, pyrene, phluoranthene, phenanthrene, chrysen, benzo(b)phluoranthene, benzo(k)phluoranthene, benzo(a)anthracene, benzo(a)pyrene, indeno(c,d)pyrene, benzo(ghi)perylene chlorinated hydrocarbons PCB(28+52+101+118 +138+153+180), HCB, α-HCH, β-HCH, γ-HCH Pesticides DDT, DDD, DDE Others styrene, petroleum hydrocarbons PCDF 2,3,7,8 TeCDF, 1,2,3,7,8 PeCDF, 2,3,4,7,8 PeCDF, 1,2,3,4,7,8 HxCDF, 1,2,3,6,7,8 HxCDF, 1,2,3,7,8,9 HxCDF, 2,3,4,6,7,8 HxCDF, 1,2,3,4,6,7,8 HpCDF, 1,2,3,4,7,8,9 HpCDF, OCDF PCB 189, PCB 170, PCB 180 PCDD 2,3,7,8 TeCDD, 1,2,3,7,8 PeCDD, 1,2,3,4,7,8 HxCDD, 1,2,3,6,7,8 HxCDD, 1,2,3,7,8,9 HxCDD, 1,2,3,4,6,7,8 HpCDD,OCDD Table 1. Persistent organic pollutants observed in Czech agricultural soils The system of limit values of soil contamination must accept sources of risky substances that influence the behaviour of risky substances in the soil (mobility, bioavailability). POPs can originate from: • Natural sources - volcanic activity (REs, POPs), natural fires (POPs) etc. • Anthropogenic sources – like industrial activities, transport emissions, the use of agro‐ chemicals and biosolids in agriculture, waste water production etc. The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic http://dx.doi.org/10.5772/ 53332

Increased inputs of potentially toxic compounds into the soils may result in soil contamina‐ tion that may negatively influence: • The ecosystem - soil functions, contamination of aquatic systems, plants, animals etc. • Plant production – the quantity and quality. • Human health – via contamination of food chain, dermal or inhalation intake etc. The efficient ways of the control and regulation of risky substances in the soil are legislative‐ ly mandatory limit values. The limit values of risky substances in the soil are derived on the basis of: - Real state of soil load by risky substances reflected natural and anthropogenic diffuse load. Limit values of this kind are usually specified as “background values” of risky substances in the soil, [6] and [7].

- Experimentally derived values, that are focused on target risk following from soil use and observed environmental component (the damage of quantity and quality of plant produc‐ tion, the reduction of soil microbial activity etc.).

One of the most effective and sophisticated limit values systems is so called hierarchical lim‐ it values system that should be able to register target risk following the soil contamination. This system is usually used in many European countries (Germany, Netherlands and Swit‐ zerland) as system of “A, B and C limits” where A – represents background values of risky substances in the soil. Generally, this limit value fulfils the principal of precaution.

B – is focused on target risk. The limit may be targeted on the quality or quantity of plant production (this approach is used rarely and is determined rather for small allotment pro‐ ducers than for agriculture) or on the decreasing of soil microbial activity and soil transfor‐ mation functions etc.

C – is used as remediation (decontamination) limit that is based on the human health risk or environmental damage.

The limit values system focused on remediation needs (in the order of C limit level) are used in some countries (Great Britain, USA – EPA methodology, [ 8]). Given limit values of risky substances delimit risky substances concentrations that may distinctly affect human health or environment. After the exceeding of this limit the site-based risk assessment must be done and the results of risk assessment study determine next approach (the remediation, land use change). The proposal of the EU Soil Protection Act [ 9] is based on similar philoso‐ phy. Three steps are required on national level of member countries: - The elaboration of soil contaminated sites register.

- The realisation of risk assessment studies on contaminated sites. - The realisation of remediation approaches.

Organic Pollutants - Monitoring, Risk and Treatment6 The directive of the Ministry of Environment of the Czech Republic No. 13/1994 Coll. [ 10] regulates the contents of REs and POPs in Czech agricultural soils. The limits of REs are de‐ termined for light texture soils and the other soils in the form of the aqua regia extract and the extract in 2M HNO 3 (cold method). The limit values for POPs are determined for the groups of monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons, chlorinat‐ ed hydrocarbons (including pesticides) and petroleum hydrocarbons. All the limit values are defined as tolerable contents of risky substances but there is no relationship to any actual risk. It brings difficulties by the evaluation and interpretation of soil load by risky substan‐ ces in many cases. Moreover the limits for POPs were assessed on the base of the values tak‐ en from Nederland because no actual values of Czech soil load by POPs were available in 1994. Two years later were published the first real data about soil load by POPs in the Czech Republic [5]. Some limit values in the directive No. 13/1994 Coll. are too low (especially some individual PAHs) because they stemm from Dutch legislation limits derived for sandy soils with low content of soil organic matter and are not suitable for Czech soils of different properties. There naturally arises the task of the proposal of the directive No.13 amendment based on the principal of hierarchical limit values system [11]. Three levels of the limits has been proposed: Prevention limit – based on background values of risky substances in Czech agricultural soils. Prevention limit were proposed for REs and POPs. The exceeding of the limit shows in‐ creased anthropogenic soil load by risky substances. From the viewpoint of limit interpreta‐ tion it is prohibited to use the sludge or sediment for soil fertilization in the case of limit exceeding. The proposed prevention limits for POPs based on the actual load of Czech agri‐ cultural soils [5] are presented in table 2.

Indication limit – was derived experimentally and the limit exceeding indicates the risk of in‐ creased REs transfer from the soil into the plants. Indication limit was proposed for REs on‐ ly. The more detailed assessment is recommended at the locality after exceeding of indication limit. In the case of POPs the transfer from soil into plants via root intake is limit‐ ed. More individual risks must be accepted for POPs indication limit and the realisation of risk assessment is recommended on the field seriously contaminated by POPs (in term of C limit level). In spite of these facts the simplified indication limits for some POPs were pro‐ posed [12], table 3. The limit values were determined as the lowest contents of risky substan‐ ces in the soil that may cause any health risk. The transfer of risky substance from the soil to human bodies by dermal, oral and dietary intake was accepted. Decontamination limit – has not been proposed yet.

The proposal of the directive No. 13/1994 Coll. amendment brings new approach to soil load by risky substances evaluation and its commencement could improve the management of contaminated sites. It could be very useful tool for the soil management in the imission re‐ gions of North Bohemia and North Moravia.

This report compares the load of two imission regions of the Czech Republic by three types of persistent organic pollutants: polycyclic aromatic hydrocarbons (PAHs), polychlorinated The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic http://dx.doi.org/10.5772/ 53332

Increased inputs of potentially toxic compounds into the soils may result in soil contamina‐ tion that may negatively influence: • The ecosystem - soil functions, contamination of aquatic systems, plants, animals etc. • Plant production – the quantity and quality. • Human health – via contamination of food chain, dermal or inhalation intake etc. The efficient ways of the control and regulation of risky substances in the soil are legislative‐ ly mandatory limit values. The limit values of risky substances in the soil are derived on the basis of: - Real state of soil load by risky substances reflected natural and anthropogenic diffuse load. Limit values of this kind are usually specified as “background values” of risky substances in the soil, [6] and [7].

- Experimentally derived values, that are focused on target risk following from soil use and observed environmental component (the damage of quantity and quality of plant produc‐ tion, the reduction of soil microbial activity etc.).

One of the most effective and sophisticated limit values systems is so called hierarchical lim‐ it values system that should be able to register target risk following the soil contamination. This system is usually used in many European countries (Germany, Netherlands and Swit‐ zerland) as system of “A, B and C limits” where A – represents background values of risky substances in the soil. Generally, this limit value fulfils the principal of precaution.

B – is focused on target risk. The limit may be targeted on the quality or quantity of plant production (this approach is used rarely and is determined rather for small allotment pro‐ ducers than for agriculture) or on the decreasing of soil microbial activity and soil transfor‐ mation functions etc.

C – is used as remediation (decontamination) limit that is based on the human health risk or environmental damage.

The limit values system focused on remediation needs (in the order of C limit level) are used in some countries (Great Britain, USA – EPA methodology, [ 8]). Given limit values of risky substances delimit risky substances concentrations that may distinctly affect human health or environment. After the exceeding of this limit the site-based risk assessment must be done and the results of risk assessment study determine next approach (the remediation, land use change). The proposal of the EU Soil Protection Act [ 9] is based on similar philoso‐ phy. Three steps are required on national level of member countries: - The elaboration of soil contaminated sites register.

- The realisation of risk assessment studies on contaminated sites. - The realisation of remediation approaches.

Organic Pollutants - Monitoring, Risk and Treatment6 The directive of the Ministry of Environment of the Czech Republic No. 13/1994 Coll. [ 10] regulates the contents of REs and POPs in Czech agricultural soils. The limits of REs are de‐ termined for light texture soils and the other soils in the form of the aqua regia extract and the extract in 2M HNO 3 (cold method). The limit values for POPs are determined for the groups of monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons, chlorinat‐ ed hydrocarbons (including pesticides) and petroleum hydrocarbons. All the limit values are defined as tolerable contents of risky substances but there is no relationship to any actual risk. It brings difficulties by the evaluation and interpretation of soil load by risky substan‐ ces in many cases. Moreover the limits for POPs were assessed on the base of the values tak‐ en from Nederland because no actual values of Czech soil load by POPs were available in 1994. Two years later were published the first real data about soil load by POPs in the Czech Republic [5]. Some limit values in the directive No. 13/1994 Coll. are too low (especially some individual PAHs) because they stemm from Dutch legislation limits derived for sandy soils with low content of soil organic matter and are not suitable for Czech soils of different properties. There naturally arises the task of the proposal of the directive No.13 amendment based on the principal of hierarchical limit values system [11]. Three levels of the limits has been proposed: Prevention limit – based on background values of risky substances in Czech agricultural soils. Prevention limit were proposed for REs and POPs. The exceeding of the limit shows in‐ creased anthropogenic soil load by risky substances. From the viewpoint of limit interpreta‐ tion it is prohibited to use the sludge or sediment for soil fertilization in the case of limit exceeding. The proposed prevention limits for POPs based on the actual load of Czech agri‐ cultural soils [5] are presented in table 2.

Indication limit – was derived experimentally and the limit exceeding indicates the risk of in‐ creased REs transfer from the soil into the plants. Indication limit was proposed for REs on‐ ly. The more detailed assessment is recommended at the locality after exceeding of indication limit. In the case of POPs the transfer from soil into plants via root intake is limit‐ ed. More individual risks must be accepted for POPs indication limit and the realisation of risk assessment is recommended on the field seriously contaminated by POPs (in term of C limit level). In spite of these facts the simplified indication limits for some POPs were pro‐ posed [12], table 3. The limit values were determined as the lowest contents of risky substan‐ ces in the soil that may cause any health risk. The transfer of risky substance from the soil to human bodies by dermal, oral and dietary intake was accepted. Decontamination limit – has not been proposed yet.

The proposal of the directive No. 13/1994 Coll. amendment brings new approach to soil load by risky substances evaluation and its commencement could improve the management of contaminated sites. It could be very useful tool for the soil management in the imission re‐ gions of North Bohemia and North Moravia.

This report compares the load of two imission regions of the Czech Republic by three types of persistent organic pollutants: polycyclic aromatic hydrocarbons (PAHs), polychlorinated The Comparison of Soil Load by POPs in Two Major Imission Regions of the Czech Republic http://dx.doi.org/10.5772/ 53332 biphenyls (PCBs) and DDTs (DDT, DDE and DDD). Although PCBs and DDTs have not been used in Europe since eighties, the load of soil by both groups of pollutants is still increased. 2. Materials and methods 2.1. The characterization of study area The area of the North Bohemian region and North Moravian region is presented in Figure 1. The area of North Bohemian region is 3,184.65 km 2 and the area of North Moravian Region is 1,834.25km2. 2.1.1. North Bohemian region 2.1.1.1. Districts The region comprises 5 districts (NUTS 5 level): Decin, Usti nad Labem, Teplice, Most and Chomutov.

District Decin is situated on the north of region and its area is 908.58km 2. In the district live 132,718 inhabitants in 52 municipalities, 14 of which are classified as towns. The capital of district is the town Decin.