Environmental

Communication

Biosci. Biotech. Res. Comm. 11(2): 291-299 (2018)

Heavy metal contamination in street precipitated dust

in Tabriz City, Iran and its ecological risk

Vakil Heidari Sareban* and Sharare Saeb

Associate Professor of Geography and Rural Planning, University of Mohaghegh Ardabili, Ardabil, Iran

ABSTRACT

Dusts are suspended particulate matters in the air, which are created from different terrestrial and human made

sources. Over time, they re-precipitate on surfaces given their size and density. Forty-nine samples of street dusts

were collected from the sideways of several main streets from the city center, the Tabriz South passenger terminal,

and one sample was collected from the yard inside Tabriz University in the summer and under dry climate conditions.

Further, the concentration of iron, manganese, zinc, lead, nickel, chromium, copper, lithium, and cadmium metals

was measured in them. The possible sources of contaminants were identi ed using correlation analysis, cluster analy-

sis, Pearson correlation coef cient, and principal component analysis. In addition, using enrichment factor (EF), the

effect of human activities on the concentration of heavy metals was assessed. The results indicated high concentra-

tions of cadmium, lead, copper, zinc, iron, chromium, and nickel compared to the mean concentration of these metals

in the Earth’s crust. The maximum concentration of copper, lead, chromium, nickel, zinc, and iron was related to

Kasaey Expressway, which is one of the most crowded expressways of Tabriz. Analysis of the results indicated that

contamination can be due to different human activities including heavy traf c of vehicles, combustion of fossil fuels,

additives added to vehicles’ fuels, corrosion of metal surfaces of automobiles, and corrosion of construction materials.

The enrichment factor values of copper, cadmium, lead, and zinc showed extremely high enrichment, with human

origin. The calculations related to the ecological risk were also performed using Hankinson method. All of the studied

points show very high ecological risk.

KEY WORDS: STREET DUSTS, HEAVY METALS, ECOLOGICAL RISK, ENRICHMENT FACTOR, TABRIZ

291

ARTICLE INFORMATION:

*Corresponding Author:

Received 9

Jan, 2018

Accepted after revision 3

March, 2018

BBRC Print ISSN: 0974-6455

Online ISSN: 2321-4007 CODEN: USA BBRCBA

Thomson Reuters ISI ESC / Clarivate Analytics USA and

Crossref Indexed Journal

NAAS Journal Score 2018: 4.31 SJIF 2017: 4.196

Online Contents Available at: http//www.bbrc.in/

DOI: 10.21786/bbrc/11.1/15

292 HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS

Vakil Heidari Sareban and Sharare Saeb

INTRODUCTION

The growth of population, industries, and vehicles has

increased the extent of pollution across cities especially

Metropolitan cities. Therefore, recently evaluation of the

quality of street dusts as pollution sources has attracted

a great deal of attention. The heavy metals in street dusts

are one of the major pollutants of urban environment,

which can be due to heavy traf c, industries, wear of

buildings, wear of rubber and peace is used in vehicles,

mineral activities, and combustion of fossil fuels, (Jir-

ies, 2003; Al-Khashman, 2007, Manasreh, 2010 Mukati,

2017).

Over the past few years, large amounts of atmos-

pheric dusts have entered cities including Tabriz through

the country’s boundaries. Although there is controversy

over their accurate origin, it is stated that their main

sources are the deserts of the neighboring countries. In

any case, signi cant amounts of them precipitate on

the surfaces of urban regions as dust. Combustion of

fossil fuels also produces some amount of heavy met-

als including nickel), chromium, lead, and manganese.

These pollutants have aggregation and carcinogenic

properties, and can develop various health and envi-

ronmental problems. Furthermore, exposure to them

can bring about low intelligence, kidney problems, and

for long-term exposure, it can cause death. Street dusts

containing heavy metals can also enter the children’s

body through hands and mouth (Watt, et al., 1993, Jiries,

2003, Balarak, 2017).

Recently, various studies have been conducted about

the concentration and distribution of heavy metals,

some of which has been performed in developed coun-

tries. In Turkey, Sezgin et al selected one of the express-

ways of this country to take samples from soil and street

dusts. The sampling was performed from both sides of

this Expressway and the tunnel. Analysis of the results

indicated that the mean lead concentration in the street

dusts was 9-11 times as large as its concentration in the

soil. Regarding copper and cadmium, the mean concen-

tration of this pollutant in street dusts was twice as large

as their concentration in soil. This number is around

9-12 times for zinc.Nickel also indicates a concentra-

tion higher than the concentration in the soil. Next, the

sources of emission of these metals are attributed to

industries and vehicle traf c (Sezgin, et al., 2003).

In another study, conducted in Lebanon by Jiries,

the sampling regions were categorized into four regions

including city center, tunnels, indoor parking lots for

vehicles, and residential areas. The maximum level of

heavy metals was observed in the tunnels, while the

minimum concentration existed in the residential areas.

Thereafter, based on the results, it was found that there

is a high correlation between lead and cadmium. There-

fore, it can be stated that these pollutants have a com-

mon emission source, (Jiries, 2003).

In a number of studies, sources of emission of heavy

metals in the soil and street dusts have been examined

using cluster analysis and principal component analy-

sis. In 1997, De Miguel used cluster analysis of Method

Ward as well as two-dimensional principle component

analysis. He considered three sources of vehicle traf c,

building construction, and natural resources among the

factors for emission of 25 types of rare metals in street

dusts in Oslo and Madrid (Miguel et al., 1997). Ordonez

et al detected the source for emission of 27 different

metals in the studied dusts samples using SPSS and

cluster analysis as human sources, natural sources, or a

combination of them (Ordonez et al., 2003).

Considering the intensi ed level of air pollution and

suspended particles in recent years in Tabriz, as well as

entrance of large dust masses in the past two years along

with the adverse effects of polluted dusts on citizens’

health and environment, the concentration of heavy

metals in this populated city should be investigated. In

the present study, the concentration of copper, cadmium,

chromium, nickel, manganese, zinc, iron, lithium, and

lead present in street dusts of Tabriz was examined to

identify the sources of production and the ecological

risk resulting from these pollutants was measured, and

 nally analyzed.

MATERIAL AND METHODS

Tabriz is a metropolitan city in the Northwest of Iran and

is the capital of East Azerbaijan province. In 2016, Tabriz

population has been around 1558693 people. This city is

the largest economic pole of the north west of Iran, and

is considered the administrative, communication, trade,

political, industrial, cultural, and military center of this

region.In recent years, the number of residents and in

turn industries in vehicles in this city has increased con-

siderably, such that today Tabriz is considered one of the

most polluted cities of the world. Tabriz climate is warm

and dry, and precipitation usually occurs during fall and

winter. For this reason, sampling was performed in the

dry season of summer and in August, when precipitation

is minimum. The sampling distribution is as follows:

Ten samples were collected from Imam Khomeini,

Azadi streets as well as Kasaei Expressway. Five sam-

ples were taken from Shotorbanan and 17 Shahrivar

streets, 14 were collected from the southern passenger

terminal, and  nally one sample was taken from Tabriz

University. The sampling from street and expressways

was performed to emphasize their vehicles and heavy

traf c as one of the most important environmental pol-

luting sources. The sampling was performed using a

BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY 293

Vakil Heidari Sareban and Sharare Saeb

sweep and blower taken from the margin of curbs at

both sides of the streets, as well as margin of curbs and

the walls of the passenger terminal. The samples were

then kept inside special bags and transferred to the labo-

ratory at a temperature less than 4°C. To ensure absence

of measurement errors and calculate the concentrations

and based on the typical method of these studies, the

samples were experimented at room temperature (less

than 40°C) until reaching a constant dry weight. There-

after, they were passed through seeves with 10, 35, 60,

and 230 scores.

RESULTS AND DISCUSSION

The granulation results of some of the samples have

been presented in Table 1. The particles with a diameter

of less than 63 micron (the diameter of the sieve pore

with score 230), which are easily scattered in the air and

become suspended and are more probable to enter the

respiratory system and develop risk to the human health

as per the method of Zhou et al., (2003) were investi-

gated.

To measure the concentration of heavy metals, acid

digestion was performed using HCl, nitric acid, and per-

chloric gram. The concentration of heavy metals was

measured by atomic absorption device (210 VGP). For

all of the analyses, the control samples and per each

10 samples, one duplicate sample underwent acid diges-

tion and was analyzed alongside other samples.The error

of the experiments was less than 6%. Cluster analysis

and principal component analysis were employed using

MVSP and SPSS 18.0 software applications to iden-

tify the possible sources of metals in street dusts, while

enrichment factor (EF) was utilized to investigate the

possible effects of human activities on their concentra-

tion (Wei et al., 2010). The EF of a metal is obtained by

the following relation:

Where, In Eq. (1), [C_x/Cref] sample represents the

ratio of the intended concentration to the reference

metal in the studied sample and [C_x/Cref] background

shows the ratio of the intended metal to the reference

metal as the background values. Five different groups of

EF values are de ned for analyzing the obtained values,

as shown in Table 2 (Yongming, et al., 2006).

To obtain the ecological risk of heavy metals, the fol-

lowing relation was used (Hakanson, 1980):

Where, in Eq. 2, C

is the concentration of the sam-

pled metal and C

shows the background values of the

metals. E

denotes the ecological risk of each element

and RI reveals the ecological risk of the sum of the ele-

ments. Hakanson (1980) has presented T

value (which

is the toxicity index of heavy metals) as 30, 5, 5, 2,

and 1 for cadmium, copper, lead, chromium, and zinc,

respectively. To analyze the obtained values, four differ-

ent groups are de ned, as presented in Table 3.

The maximum, minimum, mean, and standard devia-

tion values of the concentration of different metals

across the 50 studied samples are presented in Table 3.

The maximum concentration of copper, lead, chro-

mium, nickel, zinc, and iron is related to the sampling

points in Kasaei Expressway, which is one of the most

crowded expressways of Tabriz. Based on this point, it

Table 1. The mass percentage of particles across different sizes of the dusts

samples and some of the studied stations

0/5-20/25-0/5 0/063-0/250-0/063

Particle Diameter

(mm)

Sample number

%20/63%23/06%43/06%12/61

%34/85%39/53%21/41%1/725

%15/87%29/6%45/35%8/539

%7/49%19/26%62/62%10/5811

%9/86%34/46%38/17%16/8721

%38/85%20/92%30/69%9/2623

%50/43%22/26%23/45%2/626

%4/76%15/65%71/28%7/9231

%21/26%16/68%43/22%17/8533

%14/32%28/78%51/81%4/3140

%24/34%20/8%39/38%14/3844

%28/65%26/96%33/22%10/448

Vakil Heidari Sareban and Sharare Saeb

294 HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS

Table 2. Different groups of the range of changes in

the EF

extent of enrichmentEF values

2> EFLow enrichment

2≤ EF <5Medium enrichment

5≤ EF <20High enrichment

20 ≤ EF <40Very high enrichment

EF≥40 Extremely high enrichment

Table 3. The groups of the range of changes

in RI and ecological risk value

RI valueEcological risk value

150> RILow ecological risk

150≤ RI <300Medium ecological risk

300≤ RI <600Considerable ecological risk

RI ≥ 600 Very high ecological risk

Table 3. There values of the mean, minimum, and maximum concentration and

standard deviation of the studied cases (n=50)

standard deviationMaximumMinimumMeanElement

54/56779/3557/56223copper

0/6512/0910/110/12cadmium

12/23765/863/65253/6lead

85/3257/0915/2534/5chromium

444/5273/9513/5533/2nickel

10/982322/65699/251211/3manganese

1/651934/18400/34865/8zinc

3/988/692/687/9iron (%)

2/5517/874/549/8lithium

can be stated that the possible origin of these metals

includes the sources related to the extensive commuting

of vehicles. However, cadmium, manganese, and lithium

have different emission sources.

To investigate whether the concentration of the con-

taminant is measured in this study reveals large val-

ues or not, Table 4 compares the different heavy metals

studied around the world and in this research. Compared

to other cities, especially the cities belonging to devel-

oped countries, the concentration of cadmium, manga-

nese, zinc, iron, and lithium reveals larger values. Cad-

mium and zinc metals show far higher concentration

compared to the rest of the points, increasing the con-

cern over the high level of these pollutants in the street

dusts of Tabriz. Lead and copper, which are also among

the main pollutants on the environment, except for a

few cases, have concentrations higher than those around

the globe.

Furthermore, except for nickel, chromium, and lith-

ium, other elements have signi cantly larger concen-

trations than the mean concentration in the Earth’s

crust. Considering these three metals, one cannot say

that as they have lower values compared to the mean

earth crust level, they originate from the nature. This is

because according to Table 4, the values of these three

pollutants in other cities are also lower than the mean

value of the Earth’s crust. Since Iran is not considered an

industrial country when compared to Canada, England,

and Spain, and Table 4 has presented the data of popu-

lated cities including London, the high level of some of

the pollutants in street dusts of Tabriz is serious and it

is possibly due to other sources apart from the natural

sources.

One of the sources for emission can be considered the

fuel used in the vehicles of Tabriz, which considering its

unsuitable quality, it may show larger values for haz-

ardous pollutants in Tabriz compared to industrial and

populated cities of the world. Corrosion of the body of

vehicles, different metal surfaces across the city, as well

as the tiny particles of rubber and brake pad of the vehi-

cles are also other sources for entrance of these metals as

particulate matters in the urban environment.

IDENTIFYING THE POSSIBLE SOURCES

Enrichment factor (EF)

To identify the natural or non-natural sources of the

pollutants measured in the study, various analyses have

been used. EF values can be used to understand whether

the sources of emission of heavy metals are natural or

human-made. As shown in the formula related to EF

calculation, a value called background values required.

Across different studies, the values calculated for heavy

metals from previous studies are chosen as the back-

ground value (Manasreh, 2010; Zheng, et al., 2010).

In some of the studies, concentration of heavy metals

in the Earth’s crust has also been used as background

values (Tokalioglu, et al., 2003; Kartal, et al., 2006).

Therefore, as measuring the concentration of heavy

Vakil Heidari Sareban and Sharare Saeb

BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY 295

Table 4. The mean concentration of heavy metals present in street dusts of Tabriz and other parts of the world (ppm)

lithiumIronZincManganeseChromiumNicoleLeadCadmiumCopperDiameter

particles

(mμ)

Heavy

metals

City

9/348725/6863/61212/233/356/36255/410/5224<64Tabriz (this study)

1/725370/6410144/618/3316/279761/1249/6<200Oman (Jordan)

Jiries (2003)

53441/1481/6466/9<63Birmingham

(England)

Charlesworth, et al

179034415324662/935/5<63Kuala Lumpur

(Malaysia)Ramlan

and Badri (1989)

2600068010303/5155<500London (England)

Schwar, et al

(1998)

53621321361/71431/369<63Mutah (Jordan)

Manasreh (2010)

1930047636261441927188<100Madrid (Spain) De

Miguel, et al(1997)

9256601845345919680/6188100-250Otawa (Canada)

Rasmuseen, et al

(2000)

354/8232/467/9386/90/2172/4<63Kawala (Greece)

Christoforidis and

Stamatis (2009)

20410007595010080140/250--------The mean

concentration

of heavy metals

in the Earth’s

crust Karbassi,

et al. (2005) &

Niencheski, et al.

(2002)

metals present in street dusts of Tabriz is performed for

the  rst time in this study, due to unavailability of pre-

vious information and not developing and presenting

the background concentration values of elements for

different regions of the world by the relevant organs

(while these values have been prepared and presented by

many countries) (Jien, et al., 2011; Wei, et al., 2010), the

mean values present in the Earth’s crust have been used

as the background concentration of metals.

According to Relation 1, in addition to the back-

ground values, some other values are required as the

reference metal. Typically, the metal chosen as the refer-

ence metal has the minimum correlation coef cient with

other heavy metals, and it mostly originates from natu-

ral sources. In this study, to select the reference metal

in calculations related to the EF, correlation coef cients

of heavy metals with each other were calculated and

presented in Table 5. The correlation coef cients in this

table are Pierson coef cients.

As can be observed in Table 5, manganese, lithium, and

cadmium metals do not have a considerable correlation

with other metals. In most cases, however, they show nega-

tive correlation coef cients with other pollutants. There-

fore, they have different possible emission sources from

other pollutants. Cadmium is found in trace amounts in the

Earth’s crust and typically human activities cause elevated

concentration of this pollutant in the water, soil, and air.

There are also some studies in which lithium have been

used as the reference metal for normalizing the calcu-

lations (Niencheski, et al., 2002; Loring, 1991). There-

fore, lithium concentration was used for reference val-

ues. Using the concentration of the studied heavy metals

across the 50 sampling stations, their mean concentration

in the Earth’s crust in Table 4 and Relation 1, EF related

to each metal was calculated and presented in Table 6.

The metals with maximum EF of over 10 may mostly

be due to human activities (Yongming et al., 2006). In

any case, the high values of this factor represent enrich-

Vakil Heidari Sareban and Sharare Saeb

296 HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS

ment and possible risks of metals. Accordingly, based on

the obtained results, it can be said that copper, cadmium,

lead, and zinc are probably a result of human activities.

At least it can be stated there is a high risk factor for the

human health with exposed to these dusts.

As can be seen in Table 6, it is observed that cadmium

shows a large enrichment factor. As the reference con-

centration of this metal is very low (0.2), thus cadmium is

possibly due to human activities and could be the riskiest

metal among the studied metals here in the urban dusts

of Tabriz. The same situation applies to lead.In calcu-

lating enrichment factor which lithium as the reference

metal, the EF of nickel and chromium is close to 2, and

thus they can be partly due to human activities. In this

state, the mean EF of iron and manganese is larger than 2,

thus showing a medium enrichment level. To identify the

human or natural origin of the studied elements, principal

component analysis and cluster analysis have been used,

and the results were then compared.

Cluster analysis and Pearson correlation coef cient

To identify the possible emission sources of pollutants,

Pearson correlation coef cient was calculated using

MVSP software, with the calculation results presented

in Table 5. Based on the table, copper, chromium, lead,

nickel, zinc, and iron have high correlation coef cients.

Therefore, they share common possible emission sources.

Lithium has the largest correlation coef cient with man-

ganese. As can be observed, cadmium does not have a

considerable correlation coef cient with other pollut-

ants, suggesting a different emission source. To enhance

the accuracy of the results, the dendrogram related to

these calculations which shows the Pearson correlation

coef cient of pollutants with each other can be observed

in Fig. 2. Based on this  gure, the emission sources can

be categorized into three main groups A, B, and C. cop-

per, iron, chromium, and metal lie in Cluster A, with a

correlation coef cient of larger than 0.6. Therefore, they

may share a common emission source. Zinc, with also

a correlation coef cient of larger than 0.5, joins these

metals and has almost the same emission source.

Fig. 2. The dendrogram for cluster analysis of the pol-

lutants present in street dusts (source: MVSP software)

Considering the components constituting this cluster,

nickel, chromium, iron, lead, and copper may have dif-

ferent emission sources including combustion of fossil

Table 5. The correlation coef cient values of heavy metals with each other

lithiumIronZincManganesenickelChromiumLeadCadmiumCopper

1/000Copper

1/000-0/124Cadmium

1/000-0/2600/778Lead

1/0000/675-0/3090/653Chromium

1/0000/7820/534-0/3510/645nickel

1/000-0/401-0/259-0/1560/211-0/231Manganese

1/0000/2370/3420/4270/5290/1290/678Zinc

1/0000/589-0/1170/6670/7090/746-0/3350/873Iron

1/000-0/154-0/1190/3380/185-0/007-0/272-0/239-0/167lithium

Table 6. The spectrum of the EF values obtained considering lithium as the

reference metal across the samples

medianStandard

deviation

MaximumMinimumMean EF values

Heavy metals

117/0148/45309/4261/2942/45Cadmium

7/497/0750/252/327/09Proper

0/650/351/920/50/39Chromium

2/431/227/990/891/25Iron

0/820/593/250/350/62Nickel

31/1532/02188/348/2131/04Lead

23/3512/9964/6812/1712/15Zinc

2/790/964/551/220/95Manganese

Vakil Heidari Sareban and Sharare Saeb

BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY 297

fuels, sources originating from iron alloys (corrosion)

and possibly earth sources containing iron element to

some extent. As nickel exists in heavy fossil fuels as well

as gas oil, it is also possible that some of the elements

of this cluster may have originated from combustion

of heavier fuels and other heavy hydrocarbons sources

such as bitumen for covering the passages.

In the second main branch lies only cadmium. Con-

sidering the close-to-zero correlation coef cient it has

with Group C, and negative coef cient in conjunction

with Group C it has with Group A, its source of emis-

sion in street dusts is different from the source of other

pollutants. Manganese and lithium are in the branch C,

showing a negative and close-to-zero correlation coef-

 cient with other pollutants in other branches.It can be

stated that the main source of emission of lithium is

the nature. However, regarding manganese, as it has a

far larger concentration than the mean concentration in

the Earth’s crust, in addition to natural origin and local

soils, it may also have human sources, which are clearly

different from the sources of other heavy metal studied

here.

Principal component analysis (PCA)

Using PCA and SPSS 18.0, the accuracy of the results

obtained from the previous analyses was examined. The

principal factors extracted with a characteristic value of

over 0.7 were chosen, with Table 7 revealing the values

of the matrix containing the rotational components of

these factors. As can be observed, three main factors

were obtained from PCA.

The main factors larger than 0.5 in each group of

Table 7 have been shown. Copper, lead, chromium,

nickel, iron, and zinc have considerable back is larger

than 0.7, and thus they share the same emission source,

which are human sources. As could be predicted, man-

ganese and lithium in the second group with the fac-

tors larger than 0.5 are linked to each other and share

the same emission source, which are probably natural

sources.

With negative factors values or the very low values

it shows with other substances, cadmium has lied in the

third group and has a different source compared to other

pollutants. Therefore, it can be stated that factors 1 and

3 indicate different human sources, but factor 2 repre-

sents natural emission sources.

The three different analysis used for identifying the

emission sources of the pollutants presented almost the

same results. Therefore, the different sources of produc-

tion of these pollutants can be categorized into the three

following groups:

Group I: copper, lead, chromium, nickel, zinc, and

iron lie in this group. These pollutants are most probably

due to human activities. Studies have shown that the

main sources of emission of lead in street dusts include

additives added to vehicle fuels. Chromium, copper, and

zinc originated from wear of the alloys used in vehi-

cles as well as other services and metal materials. Iron is

also used in coverage of vehicles. Therefore, the wear of

Table 8.

Ecological risk RIcopperCadmiumLeadChromiumZincmetals

Sampling

regions

Very high1938.141.551602.55180.10.9115.1Kasaei Expressway

Very high1718.9527.511697.1785.50.7810.32Imam Khomeini

Street

Very high1705.816.251718.558.950.6110.5Azadi Street

Very high1706.0517.45160575.580.5910.1Shotorbanan Street

Very high1796.45.89174839.020.485.3917 Shahrivar

Very high1848.8924.911713100.150.6911.09Southern passenger

terminal

Very high1698.9618.811602.3418.710.5312.65Tabriz University

Table 7. The matrix of the rotational components of

the pollutants present in the street dusts of Tabriz

Factor 3Factor 2Factor 1Heavy metal

-0.065-0.2320.915Copper

0.705-0.292-0.202Cadmium

-0.122-0.2140.826Lead

-0.3810.0810.800Chromium

-0.5330.0920.721nickel

0.1240.558-0.005Manganese

0.462-0.0060.791Zinc

-0.153-0.1470.916Iron

-0.1380.890-0.045lithium

Vakil Heidari Sareban and Sharare Saeb

298 HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS

the cover used in vehicles can enhance the concentra-

tion of this element in street dusts. Industrial activities

could also be considered sources for emission of these

elements in street dusts. However, as the sampling was

performed on Regis inside the city and the margin of

streets, where no factory or a special industry existed

around the streets, the main source can be considered

wear of pieces used in vehicles. Combustion of fossil

fuels and the oils used in vehicles are among the main

sources of producing nickel. The maximum concentra-

tion of the pollutants in this group belongs to Kasaei

Expressway, which is more crowded than other regions.

Therefore, the high rate of vehicle traf c is the main

source for emission of these pollutants.

Group II: cadmium is used in producing batteries, plas-

tic, and construction materials. In this study, administra-

tive and residential buildings were abundant around the

streets. Therefore, wear of tires and battery of vehicles

as well as construction materials seems to be the main

source of cadmium emission. In any case, combustive ori-

gin for cadmium is unlikely, but its human origin in the

city and considering the illusion intensity is evident.

Group III: manganese and lithium like in this group.

Regarding the considerable correlation lithium has with

manganese and considering the relatively high concen-

tration of manganese in dusts, it seems that it is the

origin of some part of manganese present in the dusts of

natural sources containing lithium (such as the regional

soil), and the origin of some part of it includes human

sources dissimilar to the sources of other metals.

Ecological risk

To investigate the ecological risk of the sampling sta-

tions, E

and RI values were calculated by Relation 2,

with the results presented in Table 8.

All of the sampling stations indicate high ecologi-

cal risk. The maximum ecological risk is associated with

Kasaei Expressway, which is one of the most crowded

expressways of Tabriz. The minimum risk also belongs

to the dusts inside Tabriz University. Considering the

minor commute of vehicles in this point, the large space

of the University, the extent of the green space, and the

distance between the sampling point and the peripheral

lines of the University and its surrounding streets in rela-

tion to the other sampling points, the obtained results

seem to be absolutely logical. Furthermore, although

Tabriz University is not considered a crowded region

for vehicles, this point of sampling also shows a high

ecological risk. Possibly, blow of wind causes displace-

ment of polluted dusts of streets around the University,

thereby elevating its ecological risk. The mean RI across

the sampling points of the south of Tabriz indicates that

the ecological risk and concentration of pollutants in

this part of Tabriz are high and serious.

CONCLUSION

In this study, the concentration of nine heavy metals was

measured across 50 samples of street dusts in Tabriz city.

Furthermore, calculation of ecological risk resulting from

emission and identi cation of different sources of heavy

metals in street dusts were performed. Based on the cal-

culations and the analyses, three main sources including

high traf c of vehicles (the pieces used in vehicles and

combustion of fossil fuels), the pieces used in buildings,

and natural sources are among the factors for emission of

heavy metals in street dusts. Using the calculations related

to the ecological risk, all of the stations indicated high

risk. Therefore, the health risks of exposure, inhalation,

and possible swallowing of particulate matters of these

dusts across Tabriz regions are very high. Thus, more

detailed studies are required to investigate the effects and

risks resulting from this issue across Tabriz.

REFERENCES

Al-Khashman, O.A. (2007). Determination of metal accumula-

tion in deposited street dusts in Amman, Jordan. Environmen-

tal and Geochem Health. 2(9): 1-10.

Balark, D. (2017). Application of single-walled carbon nano-

tubes for removal of aniline from industrial waste water,

Bio-

science Biotechnology Research Communications, 10 (2): 311-

318.

Charlesworth, S., Alexander., R and Azlin, D. (2003). A com-

parative study of heavy metal concentration and distribution

in deposited street dusts in a large and a small urban area:

Birmingham and Coventry, West Midlands, UK. Environment

International, 2 (9): 563-573.

Christoforidis, A., and Stamatis, N . (2009). Heavy metal con-

tamination in street dust and roadside soil along the major

national road in Kavala’s region, Greece. Geoderma, 1(51):

257–263.

De Miguel, E., Midzic, S and Bjelavac, J. (1997). Origin and

patterns of distribution of trace elements in street dust:

Unleaded petrol and urban lead. Atmospheric Environment, 31

(17): 2733-2740.

Hakanson, L. (1980). An ecological risk index for aquatic pol-

lution control. A sedimentological approach. Water Research,

1(4): 975-1001.http://www.amar.org.ir/Upload/Modules/Con-

tents/asset0/jamiat89/jameiat_tehran89.pdf

Jien, Sh-H., Coble, K and Taylor, J. (2011). Baseline concentra-

tions of toxic elements in Metropolitan Park soils of Taiwan.

Trresterial and Aquatic Environmental Toxicology, 5(1): 1-7.

Jiries, A. (2003). Vehicular contamination of dust in Amman,

Jordan. The Environmentalist, 2(3): 205-210.

Karbassi, A. R., Nabi-Bidhendi, R and Bayati, G. (2005). Envi-

ronmental geochemistry of heavy metals in a sediment core off

Bushehr, Persian Gulf. Iran. Journal of Environmental Health

Science Engineering, 2(4), 225-260.

Vakil Heidari Sareban and Sharare Saeb

BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS HEAVY METAL CONTAMINATION IN STREET PRECIPITATED DUSTS IN TABRIZ CITY 299

Kartal, S., Aydin,Z., and Takalioglu. (2006). Fractionation of

metals in street sediment samples by using the BCR sequential

extraction procedure and multivariate statistical elucidation of

the data. Journal of Hazardous Materials, 13(2): 80-89.

Loring, D.H. (1991). Normalization of heavy-metal data from

estuarine and coastal sediments. ICES J. mar. Sci., 4(8): 101-

115.

Manasreh, W.A. (2010). Assessment of trace metals in street

dust of Mutah city, Kurak, Jordan. Carpatian Journal of Earth

and Environmental Sciences, 5(1), 5-12.

Mukati, K (2017),

Effect of cadmium chloride on nucleus pre-

opticus in Heteropneustes fossilis and its recovery by herbal

compound, Ashawagandha, 10 (2): 97-101.

Niencheski, Hax, L.F., Bulte, C and Hini, D. ( 2002). Lithium as

a normalizer for the assessment of anthropogenic metal con-

tamination of sediments of the southern area of Patos Lagoon.

Aquatic Ecosystem Health & Management, 5(4): 473-483.

Ordonez, A., Fish, L and Wood, L. J (2003). Distribution of

heavy metals in the street dusts and soils of an hndustrial city

in northern Spain. Archives of Environmental Contamination

and Toxicology, 4(4): 160-170.

Ramlan, N. Badri, M.A. (1989). Heavy metals in tropical city

street dust and road side soils: a case of Kuala Lumpur, Malay-

sia Environmental Technology Letters, 10(1): 435-444.

Rasmussen, P.E., Subramanian, K.S., Jessiman, B.J. (2001). A

multi-element pro le of house dust in relation to exterior dust

and soils in the city of Ottawa. Canada. The Science of the

Total Environment, 2(67): 125-140.

Schwar, M.J.R., Jain, Y and Zsoka, A. (1988). Baseline metal

in dust concentrations in Greater London. The Science of the

Total Environment, 6(8): 25-43.

Sezgin, N., Osore, M and Lima, L. (2003). Determination of

heavy metal concentration in street dusts in Istanbul E-5 high-

way. Environmental International, 2(9): 979-985.

Tokalioglu, S., Kartal, S and Birol, G. (2003). Application of a

three-stage sequential extraction procedure for the determina-

tion of extractable metal contents in highway soils. Turk J

Chem, 2(7):333-346.

Watt, J., Thornton, I and Cotter-Howells, J. (1993). Physical

evidence suggesting the transfer of soil Pb into young children

via hand-to-math activity. Appl Geochem, 5(2):269-272.

Wei, B., Steg, L and Reddy, R (2010). Heavy metal induced

ecological risk in the city of Urumqi, NW China.Environmental

Monitoring and Assessment, 1 (60):33-45.

Yongming, H., Agnew, D and Magi, E. (2006). Multivariate

analysis of heavy metal contamination in urban dusts of Xi’an,

Central China. The Science of the Total Environment, 3(35):

176-186.

Zheng, L.-G., Marhall, P and Fish, L. (2010). Some potential

hazardous trace elements contamination and their ecological

risk in sediment of western Chaohu Lake, China. Environmen-

tal Monitoring and Assessment, 1(66): 379-386.

Zhou, Y., Lima, L and Ramlan, N. (2003). Estimating popu-

lation exposure to power plant emissions using CALPUFF: a

case studying Beijing, China. Atmospheric Environment, 3(7):

815-826.