distribution of heavy metals (cd, cu, fe, ni, pb and zn...

UNIVERSITI PUTRA MALAYSIA

CONCENTRATIONS OF HEAVY METALS IN THE SOFT TISSUES OF MUDFLAT SNAILS (TELESCOPIUM TELESCOPIUM) FROM THE

INTERTIDAL AREAS OF PENINSULAR MALAYSIA

NOORHAIDAH BT ARIFIN

FS 2008 7



By


Thesis submitted to the School of Graduate Studies, Universiti Putra Malaysia, in fulfillment of the Requirements for the degree of Masters of Science

July 2008

Abstract of thesis presented to the Senate of Universiti Putra Malaysia in fulfillment of the requirement for the degree of Master of Science



By


July 2008 Chairman: Yap Chee Kong, PhD Faculty: Faculty of Science

ABSTRACT The main aim of this study is to establish mudflat snail Telescopium telescopium as a

biomonitor of heavy metals for the intertidal area of Peninsular Malaysia. From this

study, the concentrations of heavy metals in the different parts of soft tissues and

shells were determined in T. telescopium collected from 16 geographical sites along

the west coast and one site from the east coast (Tumpat, Kelantan) of Peninsular

Malaysia. Based on the 17 populations, the mean concentrations of heavy metals in

the total soft tissues of T. telescopium varied widely from 53.59 – 187.07 µg/g dry

weight for Cu, 65.11 – 155.38 µg/g dry weight for Zn, 5.59 – 17.66 µg/g dry weight

for Pb, 0.40 – 1.52 µg/g dry weight for Cd, 4.63 – 17.29 µg/g dry weight for Ni and

304.06 – 1062.19 µg/g dry weight for Fe.

The soft tissues of snail T. telescopium were dissected, separated and pooled into

seven parts namely foot, cephalic tentacle, mantle, muscle, gill, remaining soft

tissues and digestive caecum and the concentrations of heavy metals in these tissues

were measured. In the study of the relationship between different soft tissues of T.

ii

telescopium with its environment represented by sediment samples, the Pearson’s

correlation coefficients results showed positive significant correlation (p< 0.05) were

observed between Cd, Cu, Fe, Ni, Pb and Zn in the different soft tissues and

geochemical fraction of 6 metals studied in the sediment. The Pearson correlation

coefficients suggested that some soft tissues can be good biomonitoring organs (Cu:

mantle and remaining soft tissues; Fe: mantle, remaining soft tissues and foot; Ni:

gill and remaining soft tissues; Pb: gill, remaining soft tissues and digestive caecum;

Zn: gill and remaining soft tissues). It is noted that particular organ may be more

effective tool than the total soft tissues to monitor heavy metal contamination in the

intertidal zone. The study on the ratio of metals in the shell to the metals in the

different soft tissues shows that shell has higher degrees of variability for Cd, Ni and

Pb than in the different soft tissues of T. telescopium. Therefore, the results indicated

lower degrees of variability of Fe, Cu and Zn in the shells of T. telescopium than in

the different soft tissues of T. telescopium.

In conclusion, the metal distributions in the different soft tissues of T. telescopium

indicated that a particular organ is more useful and accurate to monitor a particular

metal contaminations in the intertidal area. The shells and soft tissues of T.

telescopium are found as potential biomonitor of Cd, Cu, Fe, Ni, Pb and Zn while the

usefulness of the shells need further studies.

iii

ABSTRAK

KEPEKATAN LOGAM-LOGAM BERAT DI DALAM BEBERAPA TISU LEMBUT SIPUT MUDFLAT Telescopium telescopium (Linnaeus) DARI

KAWASAN PASANG SURUT SEMANANJUNG MALAYSIA

Oleh


Julai 2008 Pengerusi: Yap Chee Kong, PhD Fakulti: Fakulti Sains

Tujuan utama kajian ini adalah untuk mencadangkan dan menggunakan siput

lumpur Telescopium telescopium sebagai agen penunjuk biologi logam-logam berat

bagi kawasan pasang surut Semenanjung Malaysia. Lokasi kajian adalah meliputi 16

lokasi sampel di sepanjang perairan Pantai Barat Semenanjung Malaysia dan satu

lokasi sampel dari perairan timur (Tumpat, Kelantan) Semenanjung Malaysia.

Kepekatan purata logam-logam berat dalam keseluruhan tisu lembut T. telescopium

berubah daripada 53.59 – 187.07 µg/g berat kering untuk Cu, 65.11 – 155.38 µg/g

berat kering untuk Zn, 5.59 – 17.66 µg/g berat kerng untuk Pb, 0.40 – 1.52 µg/g

berat kering untuk Cd, 4.63 – 17.29 µg/g berat kering untuk Ni dan 304.06 – 1062.19

µg/g berat kering untuk Fe.

Siput T. telescopium yang telah disampel dari setiap satu lokasi telah dibedah dan

diasingkan kepada tujuh bahagian iaitu kaki, tentakel sefalik, mantel, otot, insang,

lebihan tisu lembut dan sekum pencerna. Kepekatan logam-logam berat dalam semua

tisu ini diukur. Kajian ini juga menjalankan analisis bagi hubungan antara beberapa

tisu lembut T. telescopium dengan persekitaran (iaitu sedimen), keputusan

menunjukkan korelasi positif yang signifikan (p < 0.05) antara kadmium, kuprum,

iv

besi, nikel, plumbum and zink dalam beberapa tisu lembut dan fraksi geokimia enam

logam berat yang dikaji. Pemalar korelasi yang diperolehi mencadangkan beberapa

tisu lembut berpotensi untuk digunakan sebagai organ penunjuk biologi (kuprum:

mantel dan lebihan tisu lembut; besi: mantel, lebihan tisu lembut dan kaki; nikel:

insang dan lebihan tisu lembut; plumbum: insang, lebihan tisu lembut dan sekum

pencerna; zink: insang dan lebihan tisu lembut). Di dapati organ-organ tertentu

dalam siput T. telescopium lebih berkesan untuk dijadikan agen penunjuk biologi

daripada menggunakan keseluruhan tisu lembut untuk mengetahui aras kepekatan

logam-logam yang dikaji di kawasan intertidal. Kajian yang dibuat untuk

menentukan kadar logam dalam cengkerang kepada logam dalam tisu lembut

menunjukkan cengkerang mempunyai darjah berubah-ubah yang tinggi terhadap

kadmium, nikel dan plumbum berbanding bahagian tisu lembut T. telescopium. Oleh

itu keputusan kajian menunjukkan cengkerang T. telescopium mempunyai darjah

berubah-ubah yang rendah bagi besi, kuprum dan zink berbanding tisu-tisu lembut T.

telescopium.

Kesimpulannya, taburan logam-logam dalam tisu-tisu lembut T. telescopium

menunjukkan bahawa organ tertentu lebih berguna dan tepat sebagai penunjuk

biologi bagi pencemaran logam-logam tertentu dalam kawasan intertidal.

Cengkerang dan tisu lembut T. telescopium didapati sebagai agen penunjuk biologi

yang berpotensi untuk logam kadmium, kuprum, besi, nikel, plumbum dan zink,

manakala penggunaan cengkerang memerlukan kajian yang lebih lanjut.

v

ACKNOWLEDGEMENTS

First, greatly thanks to Our Almighty and Prosperous God for giving me strength and

confidence to finish my study and face all over the difficulties

I most owe a favor to my supervisor, Dr Yap Chee Kong for his guidance and given

me a lot of valuable and incalculable comments, advice and ideas. He is certainly

part of my successful completion on my project. I certainly could not achieve until

this stage without his unfailing inputs and consistent guides. Thank you very much.

Hope God will bless you for the rest of your life.

I also would like to express my profound gratitude to my co-supervisor Dr Abdul

Rahim Ismail and Dr Nor Azwady Abdul Aziz for their helpful advice, commenting

and advising on my statistical analysis. They have co-supervised me to the best of

their abilities.

Special thanks are also given to Mr Cheng Wan Hee and Mr Franklin Berandah who

helped me a lot during the field trip and also in the laboratory. To all my friends of

the Department of Biology, thank you very much.

Not forgetting my lovely and understanding husband, Mr Azlan bin Ahmad and all

my sons, you all are the most source of inspiration and motivation. I could not make

it without you all. I love you all.

vi

This thesis submitted to the Senate of Universiti Putra Malaysia and has been accepted as fulfillment of the requirement for the degree of Master of Science. The members of the Supervisory Committee were as follows: Yap Chee Kong, PhD Faculty of Science Universiti Putra Malaysia (Chairman) Abdul Rahim Ismail, PhD Faculty of Science Universiti Putra Malaysia (Member) Nor Azwady Abdul Aziz, PhD Faculty of Science Universiti Putra Malaysia (Member)

AINI IDERIS, PhD Professor and Dean School of Graduate Studies Universiti Putra Malaysia

Date :

viii

Declaration I declare that the thesis is my original work except for quotations and citations which have been duly acknowledged. I also declare that it has not been previously, and is not concurrently submitted for any other degree at Universiti Putra Malaysia or at any other institutions.

NOORHAIDAH BT ARIFIN Date :

ix

TABLE OF CONTENTS Page ABSTRACT ii

ABSTRAK iv

ACKNOWLEDGEMENTS vi

APPROVAL viii

DECLARATION ix

LIST OF TABLES xiii

LIST OF FIGURES xvii

PLATE xviii

CHAPTER

1 INTRODUCTION

1

2 LITERATURE REVIEW 5 2.1. Biology of Telescopium telescopium (Linnaeus, 1758) 5 2.1.1.Taxonomy 5 2.1.2. Species description 5 2.1.3. Telescopium telescopium, Linnaeus, 1758 7 2.1.4. Distribution of T. telescopium 8 2.1.5. Ecology/ Way of Life 8 2.1.6. Human uses 9 2.2. Rational of Using Snail as a Biomonitor 10 2.3. Heavy Metal Contamination in The Intertidal Area 14 2.3.1.. Speciation of Heavy metals in the sediment 16 2.4. Environmental Chemistry of Heavy Metals and Their

Accumulation in Aquatic Organisms 17

2.4.1. Cadmium in Aquatic Snail 17 2.4.2. Copper in Aquatic Snail 18 2.4.3. Lead in Aquatic Snail 20 2.4.4. Nickel in Gastropods 22 2.4.5. Zinc in Gastropods 22 2.5. Past Studies of Snail as Biomonitors for Heavy Metals 23 2.6. The Role of Gastropod Shells 24 3 MATERIALS AND METHODS 26 3.1. Study Area 26 3.2. Sampling procedure 26 3.2.1. Telescopium telescopium 26 3.2.2. Sediment 26 3.3. Heavy metals analysis on Telescopium telescopium 29

x

3.3.1. Sample preparation for heavy metals analysis 29 3.3.2. Sample digestion 31 3.4. Heavy metals analysis on the sediment 32 3.4.1. Sample preparation 32 3.4.2. Sample digestion 32 3.4.3. Speciation of Cd, Cu, Fe, Ni, Pb and Zn in

sediment samples 32

3.5. Determination of heavy metals (Cd, Cu, Fe, Ni, Pb and Zn) for biological and sediment samples.

33

3.5.1. Quality Assurance/ Quality Control Activities 35 3.5.2. Cleaning procedures 32 3.5.3. Blank 35 3.5.4. Recovery test 35 3.6. Calculations 36 3.6.1. Allometric ratios 36 3.6.2. Bioconcentration factor 37 3.6.3. Coefficient of variation 38 3.6.4. Statistical Analytical Procedures 38 4 RESULTS 39 4.1. Heavy metals of intertidal sediments of Peninsular Malaysia 39 4.1.1. Geochemical fractions (EFLE, acid reducible,

oxidisable organic and resistant fraction of Cd, Cu, Fe, Ni, Pb and Zn

39

4.1.2. Percentage of non-resistant and resistant fraction of Cd, Cu, Fe, Ni, Pb and Zn

54

4.1.3. Total Concentration of Cd, Cu, Fe, Ni, Pb and Zn

54

4.2. Concentration of heavy metals in the different soft tissues of Telescopium telescopium from 17 different sampling locations

56

4.2.1. Correlation between heavy metals in different soft tissues and geochemical fraction of metals in the surface sediment.

62

4.2.2. Concentration of Cd, Cu, Fe, Ni, P and Zn in the shell of T.telescopium

64

4.2.3. Bioconcentration Factors (BCF) 77 5 DISCUSSION 81 5.1. Geochemical fraction of metals in the sediment 81 5.1.1. Cadmium (Cd) 81 5.1.2. Copper (Cu) 82 5.1.3. Iron (Fe) 83 5.1.4. Nickel (Ni) 84 5.1.5. Lead (Pb) 84 5.1.6. Zinc (Zn) 85 5.2. Overall distributions of the geochemical fractions of Cd, Cu,

Fe, Ni, Pb and Zn 86

5.3 Studies on correlation on geochemical fraction of Cd, Cu, Fe Ni, Pb and Zn

88

xi

5.4. Concentration of heavy metals in the different soft tissues and the shell of Telescopium telescopium

92

5.4.1. Concentration of heavy metals in the different soft tissues of Telescopium telescopium from 17 different sampling locations

92

5.4.2. Correlation between heavy metals in different soft tissues and geochemical fraction of metals in the surface sediment.

98

5.4.3. Concentration of Cd, Cu, Fe, Ni, P and Zn in the shell of T.telescopium

102

5.4.4. Correlation coefficients of metals in the shell and geochemical fraction in the surface sediment

105

5.4.5. Comparison between the accumulation of metals in the total shell and different soft tissues of T. telescopium

107

5.4.6. Bioconcentration Factor 109 6 CONCLUSION 111 REFERENCES 114 BIODATA OF STUDENT 134 LIST OF PUBLICATIONS 135

xii

LIST OF TABLES

Table Page 2.1 Heavy metals concentrations in field collections of selected

species of mollusk (Values shown are in mg/kg or ppm fresh weight [FW], dry weight [DW] or ash weight [AW].

25

3.1 Positions (Global positioning system), sampling dates, for the intertidal sediments collected along the west coast of Peninsular Malaysia

27

3.2 Mean of shell width, shell height and volume of the shell of T. telescopium analyzed and descriptions of sampling sites in the intertidal area of Peninsular Malaysia

28

3.3 Correlation coefficients and comparative results of analyses of the direct aqua-regia and sequential extraction procedures on the sediment samples (n = 51) based on the log10 transformed (µg/g dry weight of Cu, Zn, Pb, Ni and Cd

35

3.4 Comparison of heavy metal concentrations between measured and certified values of Certified Reference Materials (CRM) of DOLT-3 Dogfish liver (National Research Council Canada) and Soil-5 (International Atomic Energy Agency, Soil-5, Vienna, Austria).

35

4.1 The Cd percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Cd concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling locations

43

4.2 The Cu percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Cu concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling locations

44

4.3 The Fe percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Fe concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling locations

45

4.4 The Ni percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Ni concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling location

46

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4.5 The Pb percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Pb concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling locations.

47

4.6 The Zn percentage of EFLE, acid reducible, oxidisable organic and resistant fraction (mean concentration ± SE in µg/g dry weight) and total Zn concentration (min-max in μg/g dryweight) of intertidal sediment collected from 17 sampling locations

48

4.7 Pearson’s correlation coefficients of dependent variables (Total aqua-regia (TOT), non-resistant (NR) and Resistant (R) of Cu, Zn, Pb, Ni and Cd) based on their log10(X + 1) transformed concentrations in µg/g in the intertidal sediments of Peninsular Malaysia

49

4.8 A comparison of total concentrations of Cu Zn, Pb, Ni and Cd in the sediments of Malaysian studies (µg/g dry weight)

55

4.9 Increasing order of Cd concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

56

4.10 Increasing order of Cu concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

57

4.11 Increasing order of Fe concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

58

4.12 Increasing order of Ni concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

59

4.13 Increasing order of Pb concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

60

4.14 Increasing order of Zn concentrations in the different soft tissues of T. telescopium (µg/g dryweight) from each sampling location

61

4.15 Mean concentrations (µg/g dry weight ± SE) of Cd, Cu, Fe, Ni, Pb and Zn from 17 sampling locations in the different soft tissues of T. telescopium

62

xiv

4.16 Results of Pearson’s Correlation Analysis, relationships between Cd concentration in the different soft tissues, different parts of shell, total shell and geochemical fraction in the sediment

62

4.17 Results of Pearson’s Correlation Analysis, relationships between Cu concentration in the different soft tissues and geochemical fraction in the sediment

63

4.18 Results of Pearson’s Correlation Analysis, relationships between Fe concentration in the different soft tissues of T. telescopium and geochemical fraction in the sediment

63

4.19 Results of Pearson’s Correlation Analysis, relationships between Ni concentration in the different soft tissues of T. telescopium and geochemical fraction in the sediment

63

4.20 Results of Pearson’s Correlation Analysis, relationships between Pb concentration in the different soft tissues of T. telescopium and geochemical fraction in the sediment

64

4.21 Results of Pearson’s Correlation Analysis, relationships between Zn concentration in the different soft tissues of T. telescopium and geochemical fractions in the sediment

64

4.22 Comparisons of Cd, Cu, Fe, Ni, Pb and Zn (mean µg/g dry weight ± standard error) in the different parts of the shell of mudflat snail T. telescopium (n=17)

68

4.23 Overall mean concentration (mean µg/g dryweight ± standard error) of the average of metals in the three different parts of the shell

68

4.24 Range concentrations (µg/g dry weight) of Cd, Cu, Fe, Ni, Pb and Zn in the shell in some molluscs’ species in previous studies

68

4.25 Pearson’s Correlation Coefficients Analysis between Cd, Cu, Fe, Ni, Pb and Zn (log10 transformed) in the shell and geochemical fraction (EFLE, oxidisable organic, acid reducible, non-resistant, resistant and total concentrations) of the surface sediment

69

4.26 Comparison between coefficient of variation (%) of heavy metal concentrations in the different soft tissues and total shell of T. telescopium

69

4.27 The mean concentration of Cd, Cd, Fe, Ni, Pb and Zn in the total shells of Telescopium telescopium collected from 17 different sampling locations of intertidal area of

70

xv

Peninsular Malaysia (N=3)

4.28 Mean concentration (µg/g dry weight) of Cd, in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

71

4.29 Mean concentration (µg/g dry weight) of Cu, in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

72

4.30 Mean concentration (µg/g dry weight) of Fe, in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

73

4.31 Mean concentration (µg/g dry weight) of Ni, in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

74

4.32 Mean concentration (µg/g dry weight) of Pb, in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

75

4.33 Mean concentration (µg/g dry weight) of Zn in the different soft tissues, total shell and ratio (shell/different soft issues) of T. telescopium collected from 17 sampling locations

76

4.34 Macroconcentrators, microconcentrators and deconcentrators and BCF Values of the shell and different soft tissues of T. telescopium for Cd, Cu, Fe, Ni, Pb and Zn.

77

4.35 Pearson’s correlation coefficients of dependent variables (Total aqua-regia (TOT), non-resistant (NR) and Resistant (R) of Cu, Zn, Pb, Ni and Cd) based on their log10(X + 1) transformed concentrations in µg/g in the intertidal sediments of Peninsular Malaysia

78

xvi

LIST OF FIGURES

Figures Page 3.1 Map showing 17 sampling location (in numbers) of the

intertidal area of Peninsular Malaysia

29

3.2 Soft tissues of T. telescopium

30

3.3 Three parts of shell of T. telescopium

31

3.4 Sequential extraction procedure adopted from the modified method of Badri and Aston (1983)

34

4.1 Geochemical fraction of EFLE, Acid reducible, oxidisable organic and resistant (Cd, Cu and Fe) from 17 intertidal area of Peninsular Malaysia in percentage

52

4.2 Geochemical fraction of non-resistant and resistant (Ni, Pb and Zn) from 17 intertidal area of Peninsular Malaysia in percentage

49

4.3 Mean concentration of Cd and Cu (µg/g dryweight ± SE) of different parts of shell from 17 sampling locations (N=3)

65

4.4 Mean concentration of Fe and Ni (µg/g dry weight ± SE) of different parts of shell from 17 sampling locations (N=3)

66

4.5 Mean concentration of Pb and Zn (µg/g dry weight ± SE) of different parts of shell from 17 sampling locations (N=3)

67

xvii

xviii

Plate Page

Plate 1a and 1b The shell description of T. telescopium 6

Plate 2 The shell covered with barnacles 6

Plate 3 Multispiral operculum 6

Plate 4 Map of Indo Pacific Area 8

Plate 5 Foot of T. telescopium 5

Plate 6 Soft tissues of T. telescopium 30

CHAPTER 1

INTRODUCTION

It has become a common practice, in many monitoring programmes, to use aquatic

organisms as biomonitors because of temporal and spatial variability of the chemical

elements in dissolved and particulate phases of aqueous systems (Phillips and

Rainbow, 1993). Furthermore, all aquatic invertebrates accumulate trace metals in

their tissues, whether or not these metals are essential to metabolism (Rainbow,

2002). Some of the intertidal gastropods that inhabit rocky shores or sediments fulfill

most of the requirements of good biomonitors (Phillips and Rainbow, 1994);

however, it is important that they accumulate metals in proportion to metal

concentrations in the environment because only the bioavailability fraction of metals

in sediments can have an impact on metal toxicity and accumulation (Ying et al.,

1993) and also metal concentrations in sediments are high and relatively invariant

with time (Mastala et al., 1992). In addition to that, gastropods were employed as

biomonitors to determine the effect of marine pollution (Bu Olayan et al., 2001;

Ismail and Safahieh, 2004; Walsh et al., 1995; Ying et al., 1993). At the same time,

gastropod snail, Telescopium telescopium is used in this study because their direct

contact to the intertidal sediments. Moreover, intertidal sediments can accumulate

large amounts of organic matter and can act as an important reservoir of trace metals,

particularly in regions of intense shellfish culture activity where natural

sedimentation is enhanced by biodeposition (Sokolowski et al., 2005). On the other

hand, organisms often exhibit greater spatial variation in metal concentration

compared to sediments and are more reliable tool for identifying sources of

contamination (Thompson et al., 1983).

According to some authors (Marigomez and Ireland, 1989; Pip, 1992; Tessier et al.,

1994), gastropods also have the ability to concentrate the bioavailable heavy metals

from their ambient environment. On the other hand, the concentrations of heavy

metals in water may vary considerably depending on annual and seasonal

fluctuations (SCEP, 1971). Therefore, the measurement in the gastropods can

provide an integrated measurement of metal bioavailability of contaminant

(Rainbow, 1995). It has already been demonstrated (Langston and Zhou, 1987;

Marigomez and Ireland, 1989) that Littorina littorea is an excellent indicator species

for monitoring environmental with heavy metal contamination particularly cadmium.

It is known that both terrestrial and marine gastropod species accumulate heavy

metals; therefore they are suitable for detection of environmental heavy metal

pollution as biomonitors organisms (Coughtrey et al., 1977; Leatherland et al., 1973;

Navrot et al., 1970; Peden et al., 1973; Stenner and Nickless, 1975). T. telescopium

was chosen for this study not only because of their abundance but also because the

maesurement of metals levels in this organisms might give an idea of the level of

metal contamination which might be present in this intertidal area of Peninsular

Malaysia. T. telescopium is also commonly used as local food. The Telescope-shell

creeper is an abundant, gregarious, spiral mollusk that occurs on estuarine mudflats

(Nair and Saraswathy, 1971). According to Ismail and Safahieh (2004) T.

telescopium can be suggested as biomonitoring agent for assessing copper and zinc

in the river. Even though T. telescopium did not show positive correlation with the

levels of metals in surface sediments many other characters such as sessile and

sedentary which are representative of the study site, hardy and tolerating high

concentrations of pollutants and large ranges in salinity, abundant, easy to identify

2

and enough tissues for analysis contaminants, have made the T. telescopium a

potential biomonitoring agent (Ismail and Safahieh, 2004) since it fulfils many of the

selected criteria of an ideal biomonitor. However, future validation is required to test

its usefulness as a good biomonitor of heavy metal pollution. Uniquely, this study

used different soft parts of T. telescopium in order to gain some information on the

ecological distribution of T. telescopium along the west ccoast of Peninsular

Malaysia and redistribution of heavy metals in snail tissues. On the other hand,

accumulation of metals varies from organ to organ in invertebrates depending upon

the balance between uptake and elimination of metals (Soto et al., 1997). So far,

metal distribution in the different soft tissues of T. telescopium are not found in the

literature.

Since, metals accumulated in the total soft tissues could be affected by many biotic

and abiotic factors apart from pollution, therefore the selection of a particular

suitable tissue/organ therefore would increase the accuracy of the determination of

metal bioavailability and contamination (Yap et al., 2006). Furthermore, knowledge

on the distribution of metals in isolated organs/tissues of marine organisms is useful

in the identification of specific organs that may tend to accumulate higher levels of

heavy metals (Szefer and Szefer, 1990). This particular information has not been

reported yet in the literature for T. telescopium.

The west coast of Peninsular Malaysia was focused upon because there is no detailed

study of metals in this snail around this region. At the same time, comparisons of

contaminant levels in a biomonitoring agent collected from different geographical

3

sites will provide on the status of the pollutant contamination of coastal areas of

Peninsular Malaysia.

In a number of previous investigations on the metal pollution of coastal sites and

estuaries, various number of the indigenous biota have been engaged to evaluate the

bioavailability levels of metals in the marine environment (Cubadda et al., 2001).

The use of bivalve or gastropod molluscs looks attractive as these organisms

accumulate metals from all environmental compartments (i.e. from the aqueous

medium and through ingestion – from food and inorganic particulate material) and

heavily concentrate them (Phillips, 1978). In addition to that, sediment samples

cannot provide enough information on bioavailability, and then analysis of the snail

would give a better answer on the bioavailability of metal which is concerns.

The objectives of this study are:

a) To determine the heavy metal distribution in different parts of soft tissues and

shells of snail, T. telescopium

b) To study the relationship of metal concentrations between the snail and their

environmental surface sediment.

4

CHAPTER 2

LITERATURE REVIEW

2.1 Biology of Telescopium telescopium 2.1.1 Taxonomy Telescopium telescopium is classified into the Family Potamididae (Houbrick, 1991).

Below is the classification of T. telescopium.

Kingdom : Animalia

Phyllum : Mollusca (Linnaeus, 1758)

Class : Gastropoda (Courier, 1797)

Subclass : Prosobranchia

Order : Mesogastropoda

Superfamily : Cerithiacea

Family : Potamididae

Subfamily : Potamidinae

Genus : Telescopium (Montfort, 1810)

Species : Telescopium telescopium (Linnaeus,

1758)

2.1.2 Species description

The Telescope-shell Creeper has a very distinctive, large, telescope-shaped shell. It

grows up to 65-110 mm in length. Its shell is large and conical in shape, with a broad

and flat base. The shell sides are straight (Plate 1a and Plate 1b). The shell sculpture

consists of numerous flat-sided whorls and spiral grooves. The shell base has

concentric cords, and a deep channel around a short, twisted, columellar pillar. The

shell is beautifully patterned under the thick layer of mud that usually covers it. The

shell is also sometimes covered with barnacles and other encrusting animals (Plate 2)

and can remain out of water for long periods (7 days) (Tan and Chou, 2000).

5

Plate 1a and 1b : The shell description of T. telescopium

Plate 2. The shell covered with barnacles

Plate 3 : Multispiral oprculum

A fouling organism: Barnacles

6

distribution of heavy metals (cd, cu, fe, ni, pb and zn...

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