EVALUATION OF THE DEGREE OF POLLUTION WITH HEAVY …biologie.uvt.ro/annals/fullaccess/vol_XI_35-50.pdf · 2020. 11. 28. · Annals of West University of Timişoara, ser. Biology,

Annals of West University of Timişoara, ser. Biology, vol. XI, pp 35-50

35

EVALUATION OF THE DEGREE OF POLLUTION WITH HEAVY

METALS OF SOILS OF TIMISOARA TOWN

Stela URUIOC

2, Mariana ALBULESCU

1, Cristian Stanco BADEA

2, Costina Roxana

URUIOC2

West University of Timisoara, Chemistry, Biology & Geography Faculty, 1Departament of Chemistry,

2Departament of Biology

ABSTRACT

Timisoara town as other urban centres is exposed to some possible dangers that

soil and plant contamination with heavy metals can produce. The our studies has

been realised on ten soil samples and three plant samples gathered from

important areas regarding pollution with heavy metals of Timisoara city. The

samples have been analyzed through atomic absorption spectrometry with a

device type Varian 2, that has a double beam. The content in cobalt, copper,

manganese, zinc, cadmium, nickel, lead, magnesium and iron from soil is

changeable under maximum admission. The content in iron, manganese, copper,

lead, cadmium from Tilia cordata leaves is situated in normal limits, but higher

than in soil.

KEY WORDS: heavy metals , pollution, soil, Timişoara, Romania

INTRODUCTION Urban environment pollution with heavy metals caught the attention of

many researchers because of his complex problems that this phenomen represents

(Duris, 1999; Lăcătuşu et al., 2001; Adomaitis et al., 2003; Panaiotu et al., 2005,

2006). Heavy metals are one of the most dangerous pollutants of urban locality

(Mîrlean et al., 1993). Development of industry and transports leads to an

excessive growth of heavy metals concetrations from big throngs. Large growth of

vehicles leads to the evacuation of big cantities of lead.

In the big industrial cities, in most of the cases, heavy metals

concentrations overpassed the alert limit, reaching to alarming toxicity levels.

Heavy metals are pollutants, with low toxic potential even to reduced levels of

exposure (Şenilă et al., 2006). Heavy metals represent one of the pollutant

category with the most important effects regarding environment quality (Har et al.,

2005). Pollution level monitorisation and the impact produced by metallic

elements represents an important purpose for environment studies in Timişoara

and near it.

Thus, Ţărău et al. (2002, 2006, 2007) brings up studies regarding soil

pollution by Termoelectrica Timişoara and environment conservation in the

periurban area. Borza et al. (2005) emphasis the impact of economic and social

activity over soil quality from periurban area Timisoara. Ianoş (2006) realises a

study regarding soil vulnerability of heavy metals pollution from Timisoara town.

The aim of this paper is to obtain new information regarding evaluation in

Timisoara town of some possible dangers that soil and plant contamination with

heavy metals can produce and their impact over environment.

URUIOC STELA et al.: Evaluation od the degree of pollution with heavy metals of soils of Timisoara town

36

MATERIAL AND METHODS For evaluting the level of soil pollution with heavy metals samples soils

have been collected from ten points spreaded in characteristic areas of Timisoara

town (Fig. 1). A soil sample has been constituted of 25 partial samples prelevated

from 0 - 5 cm depth. Also, samples of Tilia cordata leaves have been collected

from 3 important areas of the town (Fig. 2).

Collection points were established in order to avoid the eventual dangers

that heavy metals contamination can produce rergarding the main pollution

sources. For placing the collection points for soil and plants samples we used as

topographic base the map from Timisoara Town Guide. The collected soil and

plant samples were mineralised and disintegrated in OSPA Timisoara laboratories.

Figure 1. The prelevation points of the soil samples

1. I.C. Brătianu Market, crossing wich: Tache Ionescu Boulevard, Popa Şapcă Street,

Oituz Street, George Coşbuc Street; 2. Mărăşeşti Market, the revolving direction between:

Alexandru Ioan Cuza Street, Gh. Dima Street, Oituz Street; 3. Crossing: Amurgului Street,

Calea Sever Bocu, Divizia 9 Cavalerie Street; 4. Consiliului Europei Market, crossing:

Calea Aradului, Calea Sever Bocu, Calea Circumvalaţiunii, Calea Torontalului; 5.

Crossing: Republicii Boulevard, Jiu Street; 6. General Dragalina Street between: Regele

Carol I Boulevard; 16 Decembrie 1989 Boulevard; 7. General Gh. Domăşneanu Market,

revolving direction: Dr. Iosif Bulboca Boulevard, Calea Stan Vidrighin, Calea Buziaşului,

Venus Street; 8. Dâmboviţa Boulevard between: Dreptatea Street, Transilvania Street, Ana

Ipătescu Street; 9. Gh. Dima Street between: Gh. Lazăr Street, 9 Mai Street; 10. Crossing:

Cetaţii Boulevard, Calea Torontalului, Miresei Street.


37

The prepared samples were dried at 110◦C then roasted in oven at 500

◦C

and finally at 600◦C. The dross from the crucible has been treated with regal water

(HCl:HNO3 in pertained to 3:1) and held 30 minutes 70◦C on water bathroom, and

then diluted, filtered on paper with filter that has medium porosity and brought to

sign in a flask of 20 ml containing hydrochloric acid 1 N. The content in Co, Cu,

Mn, Zn, Cd, Ni, Pb, Mg, Fe from soil and also the content of Fe, Mn, Cu, Pb, Cd

from plants has been determined through spectrometry of atomic absorption with a

device Varian 2, with double beam. Before this, were assigned the standard curves

for the analyzed metals.

Soil and plant samples were processed and analyzed after national

standards and norms that were consented by the Standardization Association from

Romania (A.S.R.O).Data interpretation and processing, and also the naturalistic

characterisation of the researched area have been done according to Elaboration

Methodology of Pedologic Studies (MESP) that has been elaborated by ICPA

Bucharest 1987, and being completed with elements from The Romanian System

of Soil Taxonomy (SRTS, 2003).

Figure 2. The prelevation points of plant samples

1. Civic park, 2. Calea Aradului, 3.Calea Sagului


38

RESULTS AND DISCUSSIONS 1. Chemicals characteristics of soils

1.1.Soil reaction (pH)

Soil reactions expresses the way in which the main biochemical processees

take place from soil.

Evolution in time of pedogenetic conditions from Timisoara town shows

up that the reaction presents some characteristics that indicates inadequate

anthropic interventions.

The majority of the analyzed samples presents values (7,4-8,2) that

indicate a weak alcalin reaction (Fig 3).

Knowing the reaction of soil is important because it prevents the specialist

towards the measures that he has to undertake, in order to bring up the soil in best

condition of reaction (5,8 – 6,8) for plant growth.

Soil reaction also influences indirect the nutrition conditions of plants

through pH values influence over the main nutrition elements mobility or some

pollutants.

7.85

7.47

7.938

7.85

7.727.69

8.05

8.2

7.81

7

7.2

7.4

7.6

7.8

8

8.2

pH

Piaţa I.C.Brătianu

Piaţa Mărăşti

Intersecţia Str.Amurgului cu CaleaSever Bocu

Piaţa Consiliului Europei

Intersecţia B-dul Republicii cu Str.Jiu

Str. General Dragalina

Piaţa General Gh. Domăşneanu

B-dul Dâmboviţa

Str. Gh. Dima

Intersecţia Str.Cetăţii cu CaleaTorontalului

Figure 3. The pH value in the prelevated soil samples

1. 2. The heavy metals content from soil

From the ten soil samples prelevated from the green areas from Timisoara

town were determined the following heavy metals: cobalt, copper, manganese,

zinc, cadmium, nickel, lead, magnesium and iron.

Now we are going to make an analysis of the concetration of each metal

showing up the negative effects that higher concentration in heavy metals have on

plants and life generally.

Cobalt is an essential element for bacteries that fix natrium. These use

cobalt for fixing the atmsopheric natrium. The soil content in cobalt is tight


39

bounded by the condition of soil formation, by the nature of the parent materials

and by the anthopic interventions.

In the case of the analyzed area, the biggest concentration of Co is found

in I. C. Brătianu Market (sample 1= 0.76 ppm) while in General Gh. Domăşneanu

Market we found the lowest concentration (sample 7 = 0.413 ppm). The values

from the other points of collection are relatively similar, being situated between

0.541 ppm and 0.646 ppm. These values situates the analyzed sites in soils with

normal content of Co (Fig. 4).

0.76

0.541

0.618

0.743

0.604

0.646

0.413

0.5840.619

0.571

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 4. Variation of cobalt concentrations from soil samples

4.635

5.1755.639

4.127

4.75 4.952

2.785

4.399

2.224

4.598

0

1

2

3

4

5

6

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 5. Variation of copper concentrations from soil samples


40

Copper is present in soil in lower cantities than 20 ppm.Cantities that are

close to this value sau higher lead to the diminution of biological activity from

soil. Reaching to plants, in higher concentrations than 20 ppm, copper can become

toxic for the animals than consumes those plants (Uruioc, 2000).

Concerning copper concetrations from the studied soils these are included

between 2.224-5.639 ppm, the highest value being at the croosing between

Amurgului and Sever Bocu Street (sample 3) and the lowest value on Gheorghe

Dima Street (sample 9). Regarding these values, the analyzed soils are among the

soils that have normal concentration of copper (Fig. 5).

Manganese is found in soil, in the crystalline structure of clayey minerals,

at the surface of colloids organico-minerals (exchangeable manganese), in the soil

solution and under the form of activ manganese that is accessible to plants.

In the ten analyzed soil samples the concentration of manganese overpass

little the value 9 ppm. The only value under 9 ppm has been registered in

Gheorghe Dosmaneanu Market (sample 7 = 8.64 ppm) (Fig. 6).

The results of the analysis show up that these soils have a normal content

of manganese.

Zinc is found in soil, in clayey minerals, oxydes, hydrates and in organic

material. There is a closed bound between the content of soil in humus and the

content in zinc.

The content in zinc of the sites from the analyzed area oscillates between

2.774 ppm and 2.918 pmm. These values situates the analyzed soils to the inferior

limit of the normal concentrations (Fig. 7).

The lowest values were registered in General Gheorghe Domăşneanu

Market (sample 7) and Gheorghe Dima Street (sample 9).

Cadmium is a chemical element that is related to zinc, it is less abundant

than zinc and is known because of his toxic effect on plants and animals.

In most of the gathered samples from the investigated area the content of

cadmium is under the limit of detection of the device. Values over 0 have been

identified in I. C. Bratianu Market (sample 1 = 0.064 ppm), Marasesti Market

(sample 2 = 0.013 ppm), the crossing between Republicii Boulevard and Jiu Street

(sample 5 = 0.014 ppm) and the crossing between Cetatii Boulevard and Torontal

Street (1 ppm) In all the cases cadmium content is under the normal limit (1 ppm)

(Fig. 8).

Nickel is a stainless metal, pollutant for the natural environment and for

soils, being related from the geochemical point of view with cobalt.

Resulted in the weak of alteration processes of the primary rocks, in big

part nickel remains in solid products of physical-mechanic disintegration, then

being transported and stored in the parent material of soils.

What regards the nickel content of soils from the analyzed area this

presents low values and also contents that are between 1.947 ppm (sample 7) and

3.230 ppm (sample 1) (Fig. 9).


41

9.154

9.108

9.079

9.132

9.066 9.062

8.964

9.06

9.011 9.015

8.85

8.9

8.95

9

9.05

9.1

9.15

9.2

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 6. Variation of manganese concentration from soil samples

2.896 2.892

2.912

2.867 2.866

2.897

2.775

2.855

2.774

2.918

2.7

2.75

2.8

2.85

2.9

2.95

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 7. Variation of zinc concentrations from soil samples


42

0.064

0.013

0 0

0.041

0 0 0 0

0.053

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 8. Variation of the cadmium content from soil samples

3.23

2.423

2.625

3.013

2.535 2.557

1.947

2.446

2.689 2.637

0

0.5

1

1.5

2

2.5

3

3.5

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 9. Variation of nickel content fom soil samples


43

Lead is a chemical element, very toxic for live organisms, that it is usually

found in rocks and soils in medium cantities of 15-16 ppm (Fiedler et al., 1988).

In West Plain lead content is about 15-25 ppm (Lăcătuşu et al., 1997). The high

values identified in the Banato-Crisana Plain are derived from mountainous

massives with metamorphic and acid magmatic rocks (Lăcătuşu et al., 1997).

Being easily extracted from rocks in alteration processes, the soluble compounds

of lead are taken over by pluvial waters or by the drainage from slopes, in this way

enriching the areas descended through subsidence.

In the Timisoara area high values of lead are due to the natural background

and to the intense road traffic.

These values are under normal limits, that it is 1-20 ppm, with low

tendencies of increase in some areas. The only value over the normal limit was

identified in I. C. Bratianu Market (sample 1 = 20.379 ppm). In the other tested

areas lead contents were between 1.882 ppm and 15.522 ppm (Fig. 10).

Magnesium. In soil magnesium is found under exchangeable form and

under soluble form that is taken by plants. As concentration in magnesium come

down from the soil solution takes place the transition from exchangeable form to

soluble one.

What regards the content in magnesium of sits from the investigated area

this oscilliates between 2.532 ppm and 2.903 ppm, values that situates the

investigated area within the soils with less values of magnesium (Fig. 11).

Iron. The content in iron of the sites within the analyzed area, these

oscillate between 17.619 ppm and 18.032 ppm.

20.379

12.266

9.087

11.38

15.522

7.202

2.903

8.892

1.822

14.34

0

5

10

15

20

25

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 10. Variation of lead content from sample soils


44

2.876

2.532

2.864

2.9032.875

2.856

2.806

2.872.896 2.871

2.3

2.4

2.5

2.6

2.7

2.8

2.9

3

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 11. Variation of magnesium concentrations from the soil samples

17.619

17.697

17.753 17.748

18.032

17.852 17.863

17.907

17.638

17.672

17.4

17.5

17.6

17.7

17.8

17.9

18

18.1

ppm

1 2 3 4 5 6 7 8 9 10

sample number

Figure 12. Variation of iron content from soil samples

These values situates the analyzed sits in the soils with low extractable in

iron content. The biggest value has been registered at the crossroad between

Republicii Boulevard and Jiu Street (Fig. 12). The gathered samples from the

central-north part of Timisoara (samples 1, 2, 3, 4, 9, 10) present lower

concentrations vis a vis of those gathered from the central-south part of Timisoara


45

(samples 5, 6, 7, 8), where there are the main sources of pollution (CET Tmişoara)

(Fig . 1).

2. The heavy metals content from plants

From the obtained results there can be noticed that in plants are registered

higher contents in some heavy metals than in soil. This proves the role that

vegetation has (through retention from the atmosphere of different dusts and a

significant quantity of pollutants), especially in soil protection and generally in

environment.

Iron. In the three areas of prelevation of Tilia cordata leaves samples, iron

concentrations have been varied: in Civic Park 9400 ppm, in Calea Aradului 8000

ppm and in Calea Sagului the lowest concentration of 6400 ppm (Fig.13).

Manganese. The highest concentration of manganese has been registered

in the leaves of Tilia cordata from the Civic Park (62 ppm). The values from Calea

Aradului and from Calea Sagului have been similar, that is 28 ppm and 23 ppm

(Fig. 14).

9400

8000

6400

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

ppm

Parcul Civic

Calea Aradului

Calea Sagului

Figure 13. Variation of iron concentrations from the samples of Tilia cordata leaves


46

62

28

23

0

10

20

30

40

50

60

70

ppm

Parcul Civic

Calea Aradului

Calea Sagului

Figure 14. Variations of manganese concentrations from the samples of Tilia cordata

leaves

Copper. In the gathered samples of Tilia cordata leaves from the Civic

Park and from Calea Sagului have been registered values of copper of 1.9 ppm. In

Calea Aradului copper concentrations are reduced to half from the values of

others (1 ppm) (Fig. 15).

Lead. The highest concentration of lead (0.7 ppm) has been registered in

the samples of leaves from Civic Park from the central area of Timisoara. In Calea

Aradului lead value of 0.5 ppm and in Calea Sagului the cantity of lead was the

lowest, 0.3 ppm (Fig. 16).

Cadmium. In the prelevated samples from Calea Sagului cadmium has

been under the limit of detection of the device. From the analysis done on Tilia

cordata leaves from Calea Aradului resulted 0.2 ppm cadmium. The biggest

concentration (0.5 ppm) has been identified in the plants from Civic Park, more

than double vis a vis Calea Aradului (Fig. 17).

In order to establish some correlations between the heavy metals content

from soil and plant, we consider that it is necessary thicken the points of

observation from the areas where these substances had higher concentrations.


47

1.9

1

1.9

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

ppm

Parcul Civic

Calea Aradului

Calea Sagului

Figure 15. Variations of copper concentrations from the samples of Tilia cordata

leaves

0.7

0.5

0.3

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

ppm

Parcul Civic

Calea Aradului

Calea Sagului

Figure 16. Variations of lead concentrations from the samples of Tilia cordata leaves


48

0.5

0.2

0

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

ppm

Parcul Civic

Calea Aradului

Calea Sagului

Figure 17. Variations of cadmium concetrations from the samples of Tilia cordata

leaves

3. Determined factors in heavy metals accumulation in Timisoara town

In the urban area of Timisoara, soil means the crossing of a significant

number of pollutants: thrown or deposited solid residuals, residual waters used for

the irrigations of some areas, negative dusts thrown up by industrial factors, toxic

gases dissolved in rain water and then reached in soil.

The main factors that had an important role in heavy metals accumulation

in the soils from Timsoara are: means of transport, industrial agents, the physique

condition of soil and the climate.

The means of transport. At least once a day, the atmosphere of Timisoara

knows high concentration of gaseous pollutants and sedimentable dusts resulted

from the means of transport (Ianoş, 2006).

These are relocated on a area that is conditioned by the environmental

factors (relief aspect, wind, turbidity), or urbanistic (assembly of high block of

flats, green areas), loading the soil with some toxic elements and pollutants.

The industrial agents. The steriles come from the sterile spoil bank of

CET Timisoara is deposited in humid wethers, in the south part of Utvin. As these

spoil bank spread up, the impact will be over the phreatic, through pollution of

water adduction that dews up the sterile, being charged up with heavy metals

(cadmium, lead). After the wethers are dried, the wind spreads on the area dusts

loaded with chemical elements that are toxic for the vegetal and animal organisms,

producing air and soil pollution.

The climate. The main condition of dispersal of the pollutants is the

climate condition, factor that leads and catalyses all the transformation reactions

of the pollutants.


49

The moderate continental-temperate climate with oceanic and

mediterranean influences in which Timisoara is, had and has consequences over

the pollutant accumulation through debased reactions acceleration as well as

through soluble toxic substances pursuant to of an increased pluviometric regime.

CONCLUSIONS

After the analysation of the ten taken soil samples from the characteristic

areas of Timisoara town and three leaves of Tilia cordata samples from important

areas from the point of view of pollution with heavy metals we can conclude the

following:

The majority of analyzed soils samples present values that indicate o weak

alcalin reaction.

The content in cobalt, copper, manganese, zinc, cadmium, nickel, lead,

magnesium and iron from soils is variable even under the maximum limit

admitted.

The highest concentrations in toxic heavy metals have been identified in I.

C. Bratianu Market; in this point of soil samples prelevation, lead overpasses the

normal limit; also, we meet the highest value of cadmium but this doesn’t reach

the alert stage.

The lowest concentrations of lead have been identified in General Gh.

Domasneanu Market and Gh. Dima Street, in these 2 points cadmium value has

been under the detection limit of the device.

The content in iron, manganese, copper, lead, cadmium from Tilia cordata

leaves are situated in normal limits.

In Tilia cordata leaves are higher contents in iron, manganese, copper and

cadmium but smaller in lead.

The factors determined in the heavy metals accumulation in Timisoara

town are: the means of transport, the industrial agents (CET Timisoara), the

climate.

In order to reach to the alert stage through the growth of the pollution

stage we recommend: the endowment of the industrial agents pollutant with the

adequate filter, reduction of the vehicle traffic, usage of some unpolluting in the

case of the means of transport.

We also recommend thicken of the points of observation in order to

prepare a plantation programme of some species resistant to pollution: Acer

campestre, Alnus sp, Carpinus betulus, Fagus sylvatica, Juglans sp, Platanus

hybrida, Robinia pseudacacia, Abies sp, Pinus nigra.

According to MAPM 756/1997 order regarding the normal limits of heavy

metals from soil and relatively with other towns from the country, Timisoara can’t

be considered a polluted town.

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Documents

EVALUATION OF THE DEGREE OF POLLUTION WITH HEAVY …biologie.uvt.ro/annals/fullaccess/vol_XI_35-50.pdf · 2020. 11. 28. · Annals of West University of Timişoara, ser. Biology,