Elemental distribution in the calcite and aragonite layers of californiensis from the Iraqi Coasts—North Arabian Gulf

Moutaz A. Al-Dabbas & Mohanad H. Al- Jaberi

Arabian Journal of Geosciences

ISSN 1866-7511

Arab J Geosci DOI 10.1007/s12517-015-1862-z

1 23 Your article is protected by copyright and all rights are held exclusively by Saudi Society for Geosciences. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com”.

1 23 Author's personal copy

Arab J Geosci DOI 10.1007/s12517-015-1862-z

ORIGINAL PAPER

Elemental distribution in the calcite and aragonite layers of Chione californiensis from the Iraqi Coasts—North Arabian Gulf

Moutaz A. Al-Dabbas & Mohanad H. Al-Jaberi

Received: 28 November 2014 /Accepted: 24 February 2015 # Saudi Society for Geosciences 2015

Abstract The geochemical analysis of Chione californiensis Keywords Contamination . Chione californiensis shell . shells is carried out to study the environmental zonal varia- Chemical constituents . Iraqi coasts tion in the Iraqi coasts—north Arabian Gulf. Samples of shells and sea water are collected during low tide period from March to August 2011, from three different stations (Khor Abdullah, Khor Shytianah, and Hacham Island). The studied water samples have clearly indicated that chloride Introduction group are the dominant with one major family (Chloride- sodium family) and one water type which is rNa>rMg> The use of marine bivalves as environmental indicators has rCa; rCl>SO4. The hydrochemical analysis reflects relative- received considerable attention. Bivalves are believed to in- ly three zones of water salinity namely Khor Abdullah with corporate trace elements into their shells in proportion to the TDS ranges from 39,215 to 40,100 ppm, Khor Shytianah concentration of those elements in water (Censi et al. 2006). with TDS ranges from 44,620 to 45,220 ppm and Hacham This incorporation is also influenced by other circumstances, Island with TDS ranges from 41,190 to 41,220 ppm. X-ray including water temperature and salinity (Al-Dabbas et al. diffractometry of shells of C. californiensis reveals that they 1983 and 1984). The incorporation of trace elements into ma- have two layers, an inner layer constitutes of aragonite and rine bivalves could be used to monitor temporal changes in outer layer constitutes of calcite. The geochemical analyses aspects of the marine environment, including the elemental of the whole shell of C. californiensis reveal positive corre- composition of the water (Boening 1999). lation between water salinity, chemical constituents. Excep- Monitoring of chemical components in marine environ- tion is found for SiO2,Al2O3,andP2O5 which have nega- ment (especially in coastal zones) is very important to assess tive correlation with water salinity. The chemical constitu- the contamination in such environment (Babukutty and ents of SiO2 %, Al2O3 %, MgO %, Fe2O3 %, Co, Zn, Cr, Chacko 1995; Cravo et al. 2004). Traditional monitoring of and Pb show direct relation with the calcite whereas CaO %, heavy metals in the aquatic environment involves determining P2O5 %, Na2O%,K2O %, Ba, Sr, Rb, and Sr/Ca ratio show and comparing the metal in water, sediment, and biota (Szefer, direct relation with the aragonite. The shell of Chione et al. 2002; Liu and Kueh 2005; Hamed and Emara 2006; californiensis is found to be a useful tool for monitoring Darvish 2007). Many of the previous studies have used these contamination in the Iraqi marine environments. shells as indicator to the pollution in the coastal areas as these shells are sensitive to pollutants and hence are considered as good biomonitoring agents for pollutant and heavy metal monitoring in aquatic ecosystems (Vlahogianni et al. 2007; M. A. Al-Dabbas (*) College of Science, University of Baghdad, Aljaderia, Maanan 2008). P. O. Box: 47138, Baghdad, Iraq The molluscs’ bivalves Chione californiensis are chosen in e-mail: [email protected] this study because of their high distributions in Iraqi shore- lines. Their tolerance and adaptability to frequent periods of M. H. Al-Jaberi College of Science, University of Basra, Basra, Iraq salinity and temperature changes have made them the pre- e-mail: [email protected] ferred organisms for monitoring contaminants and constitute Author's personal copy

Arab J Geosci reliable indicators of the quality of given ecosystems. In addi- (Fig. 1). Samples of shells and water are collected during tion, C. californiensis shell is bimineralic shell, comprising low tide period from March to August 2011. Four repli- calcite and aragonite allowing investigation of trace elements cates of water and shells’ samples are collected from each in both polymorphs and knowledge the role of the surround- site. ing water in the concentration of these elements (Al-Jaberi 2013). Hydrochemical analyses were carried out to determine Iraqi coasts of the northern Arabian Gulf such as Khor the following: hydrogen number (pH), total dissolved Abdullah, Khor Shytianah, and Hacham Island are developing solids (TDS), electrical conductivity (EC), and the ma- areas (Fig. 1). Water discharge by boats and ships, marine jor cations (K+,Na+,Ca2+, and Mg 2+) and anions 2 2 transportation, ballast water discharges, and industrial dis- (Cl‾,SO4 ‾,HCO3‾,andCO3 ‾). charges are main sources of pollutants in these areas. These Thirty C. californiensis shells of the same size (4 to 7 cm) activities, along the Iraqi coasts have caused the study area to are collected from Khor Abdullah, Khor Shytianah, and be exposed to different kinds of pollutants, especially heavy Hacham Island sampling stations (Fig. 2). Nine complete metals. Bivalves especially C. californiensis are widely dis- (non-broken edges) C. californiensis’s shells were chosen tributed in this area, and there is a lack of data related to their and prepared for this investigation. heavy metal content. This research attempts to study the chemical constituents of C. californiensis is classified using Wang and Guo (2008) the calcite and aragonite layers in the shells of C. californiensis classifications, as Phylum , Class , Subclass and their relations with the sea water chemical and physical , Order Ostreina, Superfamily Veneracea, Family characteristics within the Iraqi coasts. , Subfamily Chioninae, and Genus C. californiensis. The shell samples are placed in an acid-washed polyethyl- ene bag. Debris’s are removed from each sample in the labo- Materials and methods ratory. After washing the shells with double distilled water, they were powdered by a glass mortar and were stored in Three different stations are chosen to study the geochem- polyethylene pillboxes. The scanning electron microscope, istry of C. californiensis’s shells, along Iraqi coasts, from X-ray diffraction, and ICP analysis were applied (Al- and Khor Abdullah, Khor Shytianah, and Hacham Island Mohanad 2013).

Fig. 1 Distribution of Chione californensis shells within the sampling site locations Author's personal copy

Arab J Geosci

Fig. 2 Calcite and aragonite layers in Chione californiensis shells from the studied sites

Two layers, the inner aragonite layer (nacreous layer) and Separation has been done and identified for both cal- outer calcite layer (prismatic layer), are recognized by X-ray cite and aragonite layers (Fig. 3). The purity of aragonite diffraction (CuKq) analysis and SEM; the percentages of these wastestedbyX-raydiffractionmethodandabout95% layers are different from genus to other (Al- and Mohanad 2013). purity is found to have been attained (Fig. 4). The crys- The inner aragonite layer was separated from calcite layer tals of calcite and aragonite was recognized by SEM for nine C. californiensis specimens by using an Electric Hand microscope. Both Figs. 5 and 6 show regular prismatic Vibrating Hobby tool since it is the only known method for calcite and nacreous aragonite in Chione californiensis’s separation (even that this method may contaminate the sam- shells. The chemical composition of the calcite and ara- ples in the same degree). gonite are determined in both carbonate layers. The

Fig. 3 X-ray diffractogram of calcite and aragonite minerals in the Chione Californiensis shell Author's personal copy

Arab J Geosci

Fig. 4 X-ray diffractogram of aragonite layer in the Chione californiensis shell

geochemistry of C. californiensis’s shells were acquired executed in both calcite and aragonite layers of for the following constituents: MgO %, SiO2 %, Al2O3 C. californiensis shells. Shells samples from a non- %, K2O%,Na2O%,Fe2O3 %, P2O5 %, Co, Ni, Rb, Sr, polluted site were collected and analyzed in this study Zn, Cu, Ba, Cr, Pb, and Sr/Ca ratio. These analyses were for comparison purposes.

Fig. 5 a,b Prismatic calcite crystals for Chione californiensis shell under SEM Author's personal copy

Arab J Geosci

Fig. 6 a,b Nacreous aragonite crystals for Chione californiensis shell under SEM

Result and discussion factors that are responsible for sedimentation and dissolution of different minerals. Hydrochemical analysis Chemical analysis of aragonite and calcite layers The results show that the TDS in Khor Abdullah, Khor Shytiana, and Hacham Island are 39,215–40,100 ppm, 44,620–45, Concentration of trace elements to specific carbonate shell 220 ppm, and 41,190–41,220 ppm, respectively. They are, there- layers controlled by the relative acceptability of the elements fore, saline water according to Hem (1985) water classification into the lattice and the quantity of foreign elements in the shell (Table 1). Since, there is positive relationship between electrical reflects the concentration of those elements in the surrounding conductivity (EC) and total dissolved solids (TDS). Three zones water (Dodd 1965;Chowetal.1976; Phillips 1977). Infact, have been indicated according to the EC in Khor Abdullah, Khor filter feeder, such as C. californiensis, are particularly valuable Shytiana, and Hacham Island with EC ranges from 60 to in water quality investigation, since shell variation developing 63 mmohs/Cm, 69–71 mmohs/Cm, and 64–65 mmohs/Cm, re- during growth should directly reflect the ambient water con- spectively. The hydrogen number (pH) values for Khor Abdullah dition (temperature, salinity, dissolved, and suspended load) ranges from 7.5 to7.9, Khor Shytianah ranges from 7.7 to 8, and (Phillips 1977). The ranges of the measured chemical constit-

Hacham Island ranges from 7.8 to 8.2 (Table 1). uents (MgO %, SiO2 %, Al2O3 %, K2O%,Na2O%,Fe2O3 %, The result of using Schoeller (1972) method to classify the and P2O5 %, Co, Ni, Rb, Sr, Zn, Cu, Ba, Cr, Pb, and Sr/Ca) of studied water samples, and identifying their water types have the C. californiensis shells at the studied areas in both layers of clearly indicated that chloride group are the dominant with aragonite and calcite as well as the mean values and standard one major family (Chloride-sodium family) and one water deviation of shell samples from a non-polluted site for com- type which is rNa>rMg>rCa: rCl>SO4. parison purposes are shown in Table 2. This variation can be attributed to the characterization of The results show positive correlation between the chemical the marine water or to the spatial variation in controlling constituents and sea water salinity with relatively higher

Table 1 Physical and chemical parameters of the studied sites in the Iraqi coastal marine environment

+ + 2+ 2+ 2 2 Sampling site pH EC mmohs/Cm Na K Ca Mg Cl‾ SO4 ‾ HCO3‾ CO3 ‾ TDS epm epm epm epm epm epm epm epm ppm

Khor Abdullah 7.9–8.1 60–63 566–578 7.4–8.0 25–28 123–125 651–657 64–66 3.3–3.7 0.3–0.5 39,215–40,100 Khor Shytianah 8–8.2 69–71 657–674 8.1–8.5 30.5–32.5 170–179 766–771 77–80 2.4–2.5 0.7–0.73 44,620–45,220 Hacham Island 7.8–7.9 64–65 606–609 8.1–8.3 28–30 125–131 695–700 72–73 2.5–2.8 0.6–0.7 41,190–41,220 Author's personal copy

Arab J Geosci

Table 2 The geochemical analysis of the aragonite and calcite layers for the Chione californiensis shells of Khor Abdullah (A), Khor Shytianah (S), and Hacham Island (H)

Aragonite Calcite

Elements A S H Mean S.D. Elements A S H Mean S.D.

Al2O3 % 0.066 0.04 0.051 0.053 0.013 Al2O3 % 0.11 0.09 0.087 0.09 0.012 MgO % 0.047 0.049 0.048 0.0475 0.001 MgO % 0.135 0.142 0.14 0.139 0.003

SiO2 % 0.075 0.069 0.07 0.071 0.0032 SiO2 % 0.492 0.473 0.478 0.481 0.009

P2O5% 0.069 0.060 0.062 0.063 0.004 P2O5 % 0.022 0.013 0.018 0.017 0.004

Na2O % 0.63 0.67 0.65 0.648 0.021 Na2O % 0.474 0.562 0.501 0.512 0.04

K2O % 0.1 0.14 0.12 0.118 0.02 K2O % 0.07 0.085 0.08 0.078 0.007

Fe2O3 % 0.15 0.18 0.16 0.163 0.015 Fe2O3 % 0.17 0.20 0.18 0.183 0.015 Ba ppm 13.2 14.1 13.6 13.63 0.45 Ba ppm 10.3 11.5 11.2 11 0.62 Cr ppm 20.1 20.9 20.7 20.56 0.41 Cr ppm 8.7 9.6 9.2 9.16 0.45 Pb ppm 19 24 22 21.6 2.51 Pb ppm 28 32 29 29.6 2.08 Rb ppm 1.18 2.64 1.33 1.71 0.803 Rb ppm 0.53 0.63 0.57 0.57 0.05 Sr ppm 2077 2383 2300 2253 158 Sr ppm 1042 1138 1114 1098 49 Zn ppm 180 211 190 193 15 Zn ppm 218 223 221 220 2.51 Co ppm 0.43 0.95 0.61 0.66 0.26 Co ppm 0.75 1.16 0.89 0.93 0.2 (Sr/Ca)103 5.32 6.05 5.86 5.74 0.37 (Sr/Ca)103 2.69 2.92 2.84 2.81 0.11

correlation factor values for most of the studied chemical con- Sr/Ca values in the aragonite layer are more than that of the stituents (MgO, Na2O, Fe2O3,Sr,K2O, Cu, Zn, Pb, Cr, Ba, calcite layer. The surrounding water is the main source for these Rb, Ni, and Co) of samples collected from Khor Shytianah (S) elements in the structure of C. californiensis’s shells. Shell and Hacham Island (H), as compared with those of Khor Ab- composition changes as a result of changing water chemistry dullah (A), in both layers of aragonite and calcite, except for (Yatabe et al. 2000; Dalbeck 2008). Consequently, the aquatic

SiO2,Al2O3,andP2O5 percentages, where higher values were environment had an important role in providing the calcite and found in Khor Abdullah samples (A) (Tables 1 and 2). aragonite layers by the elements (Tables 1 and 2). Some elements are concentrated in the calcite outer layer The Sr/Ca ratio can be used for determination of the more than in the aragonite inner layer. However, the ratio of paleosalinity and paleotemperature of an ancient environment the elemental distribution in calcite to aragonite layer varies as reported by Chilingar et al. (1967); Klein et al. (1996)and widely from element to other. The studied chemical constitu- Thorn et al. (1995). The Sr/Ca value is increase with increase of ents have different behaviors; they increase within the calcite water salinity, so it is higher in the Khor Shytianah and Hacham layer such as MgO, SiO2,Al2O3,Fe2O3,Co,Zn,andPb.By Island shells in comparison to Khor Abdullah’s shells (Table 2). contrast, others increase within the aragonite layer such as The Sr and Na were used as indicators to the aragonite layer,

P2O5 %, K2O%,Na2O %, Ba, Cr, Rb, Sr, and Sr/Ca. while Mg element is indicator to the calcite layer, and these In fact, one major control on trace and minor elements in results are clear in the geochemical analysis of the studied either calcite or aragonite is crystallochemical. The calcite shells, which are in accordance with McMillan et al.(2005) structure accommodates Ca2+ (ionic radius 1.00 Å) as well and Dalbeck (2008). Reeder (1983)showedthatMg2+ is able as minor and trace elements having an ionic radius less than to substitute for Ca2+ in hexagonal calcite, but not in ortho- or equal to 1.00 Å. The aragonite structure accommodates rhombic aragonite. Therefore, the decrease of calcium element Ca2+ together with minor and trace elements having radii close in the calcite layer and increase of the magnesium can be at- or greater that 1.00 Å (Deer et al. 1992). tributed to higher paleotemperature in the Iraqi shorelines. The results reflect that Mg, Si, Al, and Zn, which have large Generally, most P, Si, and Al are related to surfacial con- ionic radii, are present in higher concentration in the calcite tamination and to interstitial grains of amorphous silica or than in aragonite layer, especially Zn element. Pb element, clays. The factors controlling trace elements concentration in which also has large ionic radius, is present in higher concen- clay are influenced by pH–Eh, drainage, climate, time, clay tration in the calcite layer comparable to the aragonite layer. fraction content, organic matter content, pollution, and other On other hand, Cr and P elements which have small ionic factors (Caihuan and Wang 2001). However, it is believed that radii, are present at higher concentrations in aragonite rather the clay content is relatively higher in Khor Abdullah, due to than calcite. the influence of sediment transport loads that are carried Author's personal copy

Arab J Geosci annually by Shatt Al-Arab fresh water river to the sea water, Caihuan K, Wang W (2001) Bioaccumulation of Cd, Se, and Zn in an estuarine oyster Crassostrea rivularis and a coastal oyster consequently, relatively reducing the sea water salinity, as well – ’ Saccostrea glomerata. Aqua Toxic 56:33 51 as the ions concentration. Biomonitors organisms accumulate Censi P, Spoto SE, Saino FM, Sprovieri S, Mazzola A, Nardone G (2006) the chemical constituents and heavy metals from ambient bio- Heavy metals in coastal water systems: a case study from the north- available sources of the trace metal over a period (Rainbow western gulf of Tailand. Chem 64:1167–1176 2006). The C. californiensis like other molluscs’ is suspension Chilingar GV, Bissel HJ, Wolf KH (1967) Diagenesis of carbonate rocks. In: Larsen G, Chilingar GV (eds) Diagenesis in Sediments. Elsevier, feeder and can uptake the heavy metals from suspended sed- Developments in Sedimentology, Amsterdam 8:179–322 iment (Caihuan and Wang 2001). Thus, the shells of Chow TJ, Snyder HG, Synder CB (1976) Mussels (Mytilus sp.) as an C. californiensis were found to be useful tool for monitoring indicator of lead pollution. Sci Total Environ 6:55–61 contamination (Shulkin et al. 2003). Cravo A, Foster P, Bebianno MJ (2004) Minor and trace elements in the – The pollution in the Iraqi coasts water may be formed as a shell of Patella aspera. Environ Int 28:295 302 Dalbeck PC (2008) Crystallography, stable isotope and trace element result of the oil spill by the oil carrying ships in the navigation analysis of Mytilus edulis shells in the context of ontogeny. channel in the north and northwestern parts of the Arabian Gulf. Unpubl. MSc thesis, University of Glasgow, p 235 Darvish A (2007) The survey of heavy metals (Cd, Cu, Ni and Hg) in water and soft tissue of Saccostrea cucullata in intertidal zone of Hormoz islans. Persian Gulf, MS thesis, Environmental Conclusions Engineering, Azad University of Ahvaz, Iran Deer WA, Howie RA, Zussman J (1992) An introduction to the rock- forming minerals: Harlow (Longman) The environmental pollution increased at Khor Abdullah, Dodd JR (1965) Environmental control of strontium and magnesium in Khor Shytianah, and Hacham Island during the last few Mytilus. Geochim Cosmochim Acta 29:385–398 years. The main sources of pollutants may be originated Hamed AH, Emara AM (2006) Marine molluscs as biomonitors for from oil spill. heavy metal levels in the Gulf of Suez, Red sea. J Mar Syst 60: – The geochemical analysis results show that positive cor- 220 234 Hem JD (1985) Study and interpretation of the chemical characteristics of relations are found between water salinity of the sampling natural water (3rd ed.). USGS water- supply papers-2254. 253p sites and the chemical constituents in C. californiensis Klein RT, Lohmann KC, Thayer CW (1996) Sr/Ca and 13C/12C ratios in shells analyzed two layers of calcite and aragonite. While skeletal calcite of Mytilus trossulus: covariation with metabolic rate, negative correlation is found between water salinity and salinity, and carbon isotopic composition of seawater. Geochim Cosmochim Acta 60:4207–4221 SiO2,Al2O3 and P2O5. It is believed that the clay content Liu JH, Kueh CSW (2005) Biomonitoring of heavy metals and trace and fertilizers are relatively higher in Khor Abdullah due organics using the intertidal mussel Perna viridis in Hong Kong to the influence of Shatt Al-Arab sediments transport coastal waters. Mar Pollut Bullet 51:857–875 loads to the sea water of the Arabian Gulf. Maanan M (2008) Heavy metal concentrations in marine mollusks from the Moroccan coastal region. Environ Pollut 153:176–183 The major control on trace and minor elements in either McMillan EA, Fairchild I, Frisia S, Borsato A, McDermott F (2005) calcite or aragonite is crystallochemical, clay content, and Annual trace element cycles in calcite–aragonite speleothems: evi- the surrounding water chemistry. dence of drought in the western Mediterranean 1200–1100 yr BP. J The shell of C. californiensis is found to be a useful tool Quat Sci 20(5):423–433 for monitoring contamination in the Iraqi marine Phillips DJH (1977) The use of biological indicator organisms to monitor trace metal pollution in marine and estuarine environments—are- environments. view. Environ Pollut 13:281–317 Rainbow PS (2006) Biomonitoring of trace metals in estuarine and ma- rine environments. Australas J Ecotoxicol 12:107–122 Reeder RJ (1983) Crystal chemistry of the rhombohedral carbonates. In Reeder RJ (ed) Carbonates: mineralogy and chemistry, V11. References Reviews in Mineralogy, pp-1–47 Schoeller M (1972) Edute Geochemiique De La Nappe Des, Stables in fericurs Du Bassin D,aquitainse. J Hydrol 15:317–328 Al- Jaberi, MH (2013) Study the clastics and shells in the Iraqi shore lines, Shulkin VM, Presley BJ, Kavun VI (2003) Metal concentrations in mus- Unpublished PhD thesis, Baghdad University. 220P sel Crenomytilus grayanus and oyster Crassostrea gigas in relation Al-Dabbas M, Hubbard FH, McManus J (1983) The proportion of ara- to contamination of ambient sediments. Environ Int 29:493–502 gonite in the shells of Mytilus edulis from the Tay estuary. JAWRR Szefer P, Frelek K, Szefer K, Lee CB, Kim BS, Warzocha J (2002) 2(2):73–79 Distribution and relationships of trace metals in soft tissue, byssus Al-Dabbas MAM, Hubbard FH, McManus J (1984) The shell of Mytilus and shells of Mytilus edulis trossulus from the southern Baltic. as an indicator of zonal variations of water quality within an estuary, Environ Pollut 120:423–444 estuarine, coastal and shelf. Science 18:263–270 Thorn K, Cerrato RM, Rivers ML (1995) elemental distributions in ma- Babukutty Y, Chacko J (1995) Chemical partitioning and bioavailability rine bivalve shells as measured by synchrotron X-ray fluorescence. of lead and nickel in an estuarine system. Environ Toxicol Chem 14: Biol Bull 188:57–67 427–434 Vlahogianni M, Dassenakis M, Scoullos MJ, Valavanidis A (2007) Boening W (1999) An evaluation of biomonitors of heavy metals pollu- Integrated use of biomarkers (superoxide dismutase, catalase and tion in marine waters. Environ Monit Assess 55:459–470 lipid peroxidation) in mussels Mytilus galloprovincialis for Author's personal copy

Arab J Geosci

assessing heavy metals’ pollution in coastal areas from the Yatabe A, Vanko D, Ghazi A (2000) Petrography and chemical compo- Saronikos Gulf of Greece. Mar Pollut Bull 54(9):1361–1371 sition of secondary calcite and aragonite in Juan de Fuca Ridge Wang H, Guo X (2008) Identification of Crassostera Ariakensis and related basalts at low temperature. Proceedings of the Ocean Drilling oysters by multiplex species PCR. J Shellfish Res 27(3):481–487 Program, Scientific Results, 168.