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Spatial Distribution and Source Identification of Heavy Metals in Surface Waters of Three Coastal Areas of Tunisia

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The concentrations of selected dissolved trace elements (Ni 446-919 μg L⁻¹, Pb 383-1015, Fe 195739, Cu 217-318, Cr 156-336, Zn 9-236, Mn 0-187, Co 0-310, and Cd 26-77) were assessed in the surface water of 30 stations belonging to three coastal areas along the Gulf of Gabes, i.e., the southern (stations 1-10) and northern (stations 11-20) coastal areas of Sfax and the Ghannouch area (stations 21-30) during October and November 2014. Results showed that dissolved metals in surface waters, which were analyzed by means of flame atomic absorption spectrophotometry, followed the concentration levels (Pb>Ni>Fe>Cu>Cr>Co>Mn>Cd>Zn) on the southern and (Ni>Pb>Fe>Cu>Cr>Zn>Mn>Co>Cd) on the northern coasts of Sfax, and (Ni> Fe>Pb>Cu>Cr>Zn>Co>Cd>Mn) in the Ghannouch area. In the southern and the northern coasts of Sfax, all analyzed metals were detected in 100% of sampled stations except Co, which was revealed in 90 and 80% of stations, respectively. However, in the Ghannouch area all analyzed metals were detected in 100% of sampled stations except Mn, which was revealed in 70% of stations. These trace elements, except for Fe and Mn, exceeded the safety limit of the USEPA water quality criteria for the protection of aquatic fauna and flora survival and their uses. The Sfax and Ghannouch coastal areas should be considered relatively polluted with metals (Zn, Ni, Pb, Co, Cr, Cd, and Cu). The elevated metal contents were attributed to anthropogenic waste inputs around the study area. The main sources of Ni and Co loading in the seawater were the SIAPE phosphoric acid and fertilizer plant and a waste water treatment plant located close to station 1. Whereas the fishing harbor of Sfax, which is situated on the southern coast (station 9), is the second source of high amounts of Cd, Mn, Cr, and Pb. This situation has led to serious human health risks and chronic toxicity caused by their potential bioaccumulation in some aquatic fauna such as shrimp, fish, crab, shellfish, mollusk, and cephalopoda.
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Pol. J. Environ. Stud. Vol. 26, No. 3 (2017), 1057-1069
Original Research
SpatialDistributionandSourceIdentication
ofHeavyMetalsinSurfaceWaters
ofThreeCoastalAreasofTunisia
ZaherDrira1*,HoudaSahnoun2,HabibAyadi1



Received: 13 October 2016
Accepted: 4 December 2016
Abstract
         
                 
       
     
   

       

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
         
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
Keywords          


10.15244/pjoes/67529
1058 Drira Z., et al.
Introduction
     
       
        
      

       
       
        
         
     



      

     


      
       

 









       
 



Posidonia
meadows     
        

      
       
       
       
Posidonia Oceanica  

       


    


        

         
          

      
       


       
      

      
    
 

 
         
       

        
 
   

       
       
      
     
       
       
   
       
       
         
Diplodus annularis  Sarpa
salpaSepia ofcinalis  
  Ruditapes decussatus   



       



       

      

       

      
     

MaterialandMethods

      
       
        
      
       
1059
Spatial Distribution and Source...
 

 
 



      


         

      

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      


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
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
 
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

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


     

         

                  

1060 Drira Z., et al.

      


      


  
      
        
    
          

  


ResultsandDiscussion




  
      
    



        
 
          
  


    
         







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    
    
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        
        
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
        
   
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 
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     
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     
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      
     
1061
Spatial Distribution and Source...









    





F 



         
Ni
             
Pb               
Fe               

Cu
              

Zn             

Co
           
Mn
             
Cd
              
Cr
            
1062 Drira Z., et al.



1063
Spatial Distribution and Source...
      
  


       
          
   

  

      
     
       
      
           
            
       
        
       
       
       
       
     
       
     
 
          


      
         





    
         
     

 
 







       
       
      
       
          
    
    

1064 Drira Z., et al.

        

 

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
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
       






        








        


  
  



  
       

  
          
        
  
         

       
       
       
       

  
       




        
    
        


       


 
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

  


        

          



    
      





   

   

1065
Spatial Distribution and Source...
 
        
        
       
        
       
   
 



      

        
        
      
          


  




          
    
 
        
      
     




 




 
       


  






       
      
 
      
  


      


   
     
 
      

        
 


       
        
       
     
      
        
      
      
         


      
        
      
      


      
      
      
      
        


       
 

      
       
         
      
       
      


     
       
 

       

         


      
      
        
         
      
1066 Drira Z., et al.
 



        


Conclusions
  



 
      
         
       
   
    

  
  







      


      
          


     






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Acknowledgements
       
      


    
 
   
      

 


  

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 

   .     12 
2001
 


12
2012
 


862014
       
    
  
542007
    
 46
2012
 


       14 
2012
   

     
1852013
      



872014
 

832014
       


      
92016
     


        
62016
  
  
452000


632006


352011
1067
Spatial Distribution and Source...
      
       
532001

922011
      



3892008



642012

 
272001


       
1472007
 

202008
       
       
  

922011



892014
   
         
117
2006

    
1042007
       
         
472009
     
       

2014
      

       

252005
     
     
    
      
       
592009
   


2022009
      
       

582009

2004
    
      
Sardinella
aurita90
2010
        


722008
       
  


892009
       

       

902010a
       
  
       

902010b

   
      
212014
      

Posidonia oceanica

702010
     
      


 104
2016
 

      90 
2009
      
     
  
         

2009


       
502005
      
      
        
  
722014



62012
   
       
1068 Drira Z., et al.

1802011
     
 Ruditapes decussa-
tus28
2003
     

Ruditapes decussates
1432006


3272004

 1999


     
2014



52005

         

302011
    



62014
       
       
  
232016a
 
Diplodus annularisLiza aurataSolea vulgaris


232016b
  

22008
      
 

22008




672015
    
 
 312004
       
     

82015
       
        

1999

Hexaplex trunculus

232016


151988
     


71980
       
  
     

1842012
      




1012015
       
   
  
     

952015

      
     
1990


1993
    


12011


52014
      
   
58
2015
      

1991

      
 
612010
         


1012015


1999

2005

1999


Daphnia pulex
912009
1069
Spatial Distribution and Source...

      15 
2006


1991
       
        


32011

   

2000
       

136
1990


1102000
 
      
52011


22012



62012

   
762013
   
     
184
2012
        
     
Salaria basiliscaZosterisessor ophiocephalus
Solea vulgaris
212009

3
1994
 


1262014
... Many studies have focused on the quantification of dissolved forms of lead concentrations in offshore and coastal waters ( Table 2) (Patterson et al. 1976;Paulson and Feely 1985;Fowler 1990). Concentrations of these dissolved and particulate forms of lead in coastal waters are very heterogeneous ranging from 0.001176 µg/L (Beagle Channel, Patagonia, Argentina; Conti et al. 2012) to 1015 µg/L (Gulf of Gabes, Tunisia; Drira et al. 2017). The Gulf of Gabes, situated in the Southeast of Tunisia, has been reported heavily polluted because of the increase in urbanization, industrialization, tourism, and intensive fishing activity (Drira et al. 2017). ...
... Concentrations of these dissolved and particulate forms of lead in coastal waters are very heterogeneous ranging from 0.001176 µg/L (Beagle Channel, Patagonia, Argentina; Conti et al. 2012) to 1015 µg/L (Gulf of Gabes, Tunisia; Drira et al. 2017). The Gulf of Gabes, situated in the Southeast of Tunisia, has been reported heavily polluted because of the increase in urbanization, industrialization, tourism, and intensive fishing activity (Drira et al. 2017). Lead concentrations in offshore waters are ranging from 0.0035 (American Samoa, South Pacific Ocean) to 0.150 µg/L (Western Mediterranean Sea; Copin-Montegut et al. 1986a, b). ...
... Indeed, lead contamination has negative consequences on various phyla and these effects are also diversified even though studies mainly focused on the effects of this metal on early life stages. If we compare the EC 50 in various marine organisms (Table 4) and lead environmental coastal concentrations (Table 2), we can see that EC 50 values for molluscs and echinoderms (except for Sea urchin Arbacia punctulata) are lower than the highest concentration found in the literature (1015 µg/L, Gulf of Gabes, Tunisia; Drira et al. 2017). Therefore, we can hypothesize that these marine organisms ...
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Lead (Pb) is a non-essential metal naturally present in the environment and often complexed with other elements (e.g., copper, selenium, zinc). This metal has been used since ancient Egypt and its extraction has grown in the last centuries. It has been used until recently as a fuel additive and is currently used in the production of vehicle batteries, paint, and plumbing. Marine ecosystems are sinks of terrestrial contaminations; consequently, lead is detected in oceans and seas. Furthermore, lead is not biodegradable. It remains in soil, atmosphere, and water inducing multiple negative impacts on marine invertebrates (key species in trophic chain) disturbing ecological ecosystems. This review established our knowledge on lead accumulation and its effects on marine invertebrates (Annelida, Cnidaria, Crustacea, Echinodermata, and Mollusca). Lead may affect different stages of development from fertilization to larval development and can also lead to disturbance in reproduction and mortality. Furthermore, we discussed changes in the seawater chemistry due to Ocean Acidification, which can affect the solubility, speciation, and distribution of the lead, increasing potentially its toxicity to marine invertebrates
... The southern coast of Sfax is marked by five major sources of pollution namely the commercial port, the new fishing port and the outlets of the Sidi Salem runoff Channel, the Hakmouni Channel and the El Maou wadi [22]. These different sources release effluents contaminated with phosphates, fluorides, sulfates, natural radionuclides, heavy metals and other trace elements, organic matter, hydrocarbons, polyphenols, flavonoids, and tannins [23][24][25][26][27]4,28,29]. In the Ghannouch/Gabes area chemical industries and a commercial port were implemented during the seventies [15]. ...
... The same F 2 axis encompassed NC (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) selecting positively pH, salinity, T-N, NO 2 -, NO 3 -, Si(OH)4, HCO3-, Mg2+, Mn2+, Ca2+, K+, flavonoid compounds, SPM and SPM/BOD 5 . The F 1 axis (19.41%) selected negatively the GA stations (21)(22)(23)(24)(25)(26)(27)(28)(29)(30) with T-P, PO 4 3-, Depth and Fe 2+ + Fe 3+ . ...
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Physical, chemical and biogeochemical variables were studied in the surface waters of three coastal areas characterized by different degrees of pollution (the Sfax Northern (NC) and Southern coasts (SC) and the Ghannouch area of Gabes (GA)) during October and November 2014 in order to identify pertinent tracers of anthropogenic inputs and depict their spatial distribution. The SIAPE (SC) and the GCT (GA) were the main sources of inorganic pollutants such as PO 4 3-, HCO 3-, Cl-and SO 4 2-. High contents in total polyphenolic and flavonoid compounds were observed in the SC due to the olive oil treatment waste water released from margins, notably contributing to the increase of COD concentration. The BOD 5 /COD ratio was < 0.5 for 50% of stations; it thus underscored a pollution of chemical origin. The COD/BOD 5 ratio was > 3 just for 30% of the SC stations which underlined an organic load resistant to biodegradation due to the high content in polyphenolic compounds.
... However, in coastal waters the concentrations of dissolved Pb can frequently surpass >1 μg/L (Neff, 2002). According to a recent review study by Botté et al. (2022), Pb concentrations ranging from 1.176 ng/L (Beagle Channel, Patagonia, Argentina (Conti et al., 2012)) to 1015 μg/L (Gulf of Gabes, Tunisia (Drira Zaher and Sahnoun, 2017)) have been reported in coastal waters. In bivalves, Pb has already been found in different species. ...
Article
Lead and Lithium are metals which have been detected in the environment and, at high concentrations, can induce toxic effects that disturb the growth, metabolism or reproduction of organisms along the entire trophic chain. The impacts of these metals have scarcely been investigated using marine bivalves, especially when acting as a mixture. The present study aimed to investigate the influence of temperature on the ecotoxicological effects caused by Pb and Li, acting alone and as a mixture, on the mussel species Mytilus galloprovincialis after 28 days of exposure. The impacts were evaluated under actual (17 °C) and projected (+4 °C) warming conditions, to understand the influence of temperature rise on the effects of the metals (both acting alone or as a mixture). The results obtained showed that the increased temperature did not influence the accumulation of metals. However, the biomarkers evaluated showed greater responses in mussels that are exposed to metals under increased temperature (21 °C). The IBR index showed that there is a comparable toxic effect of Li and Pb separately, while exposure to a mixture of both pollutants causes a significantly higher stress response. Overall, the results obtained revealed that temperature may cause extra stress on the mussels and exposure to the metal mixture caused the greatest impacts compared to each metal acting alone.
... The number of large and small rivers flowing in coastal waters will transport agricultural waste, industrial waste, and anthropogenic waste from the mainland (Tanjung et al., 2019). These conditions can interrupt the potential in coastal and marine waters as a source of food for the public (Chen et al., 2007;Tjahjono et al., 2017;Drira et al., 2017). The increasing pollution levels in the coastal regions and degradation of marine resources of the country are emerging as important an environmental threat that needs immediate action. ...
Article
Full-text available
In Pakistan, marine pollution is a major problem that is caused by the waste from industrial, municipal, agronomy, and oil leak sources. The pollutant loads along with the coastline areas near Karachi is received from terrestrial contaminants including discharges from Karachi Harbour located on the estuary of the Lyari river. Karachi generates 472 Million Gallon per Day (MGD) of wastewater out of which only 55 MGD is treated and the rest is discharged in the sea. The prevailing sewage treatment plants are functioning at reduced capacity due to the insufficient transmission capacity of interceptors. Water sampling was carried out from the Lyari River and five different selected coastal point around Karachi harbour for physicochemical parameters and selected heavy metals. Results show that the Karachi Harbour area is noticeably polluted, whereas; the coastal environment in the vicinity of Karachi is also under the stress of pollution. High COD and BOD5 values were noticed at the Lyari river samples and the sampling locations close to the Lyari river outfall area. The Pb, Cd, Ni, and Hg heavy metals that pollute marine water are found. This situation is due to the discharge of mixed effluents of industrial and domestic wastes as well as dredging, cargo handling, dumping of ship waste and other coastal activities. The highest value of pollution observed at Karachi Harbour which is near Lyari river mouth, where the domestic and industrial effluents with organic and inorganic wastes have a greater influence on the water quality and the marine environment. At present, there is no effective controlling mechanism for industries to treat their waste, nor has any investigation to assess increasing marine pollution been carried out. As a result, there is an adverse impact on fish habitat and mangroves, corrosion of cargo ships, naval vessels and the residents living in the coastal area. Therefore, the government agencies and industrial sectors should work together to avert marine pollution and attain total environmental sustainability.
... In the latter, heterotrophic and mixotrophic protozoans, including dinoflagellates, nanoflagellates and ciliates, can reach high concentrations up to maximum of 10 9 cells L −1 , suggesting their strong top-down control on phytoplankton Hamdi et al. 2015;Feki-Sahnoun et al. 2017. High abundance of the mesozooplankton, mostly dominated by herbivorous copepods, was also reported in this area (Hannachi et al. 2008;Drira et al. 2009Drira et al. , 2017Makhlouf Belkahia et al. 2021). The previous studies in the Gulf suggest the dominance of the multivorous food web, where microbial and herbivorous pathways both would play important roles in channeling carbon. ...
Article
The planktonic food web structure was investigated in a productive Mediterranean gulf during spring and fall. Plankton communities, rates of primary production (PP), bacterial production (BP) and grazing by microzooplankton and mesozooplankton were examined in a station influenced by Saharan dust, St1; a station located in the Boughrara Lagoon, St2; and a polluted station, St3, close to a phosphate industrial site. The high nutrient (12–17 µM) and chlorophyll a (Chl a) concentrations (3.7–16.9 mg m−3) as well as the high rates of PP (1123–2638 mg C m−2 d−1) and BP (128–1337 mg C m−2 d−1), recorded throughout the sampling period, indicated the eutrophic character of the study site. Microzooplankton and mesozooplankton mostly showed seasonal changes in their composition and grazing rates. During spring, PP was dominated by nano- and micro-sized fractions, but pico-, nano- and microphytoplankton contributed equally to Chl a. Heterotrophic and mixotrophic microzooplankton consumed significant proportions of the daily production for bacterioplankton (50–72%) and size-fractioned phytoplankton (25–86%), whereas herbivorous copepods grazed daily on 13–15% of PP. These trophic links suggested that the multivorous food web prevailed in spring. During fall, picophytoplankton, mainly Synechococcus, dominated the Chl a and PP in St1, where microbivorous microzooplankton (mainly mixotrophic dinoflagellates) grazed ≥ 50% of the production of bacterioplankton and picophytoplankton, while mesozooplankton, dominated by detritivorous copepods, removed only 5% of PP, suggesting a microbial food web. In St2 and St3, Chl a and PP were dominated by large phytoplankton, which was substantially grazed by heterotrophic and mixotrophic microzooplankton (42–62% grazed d−1) and copepods (12–25% grazed d−1), indicating a carbon channeling throughout the herbivorous food web. The seasonal and spatial change in the planktonic food web implies different efficiencies in the export of carbon. Even in productive waters, picophytoplankton along with microzooplankton, including mixotrophic and heterotrophic organisms, significantly contribute to the ecological functioning of these systems and play a central role in structuring the carbon transfer pathway.
... Systematic monitoring is essential to extract critical ecological indicators of surface water by assessing physicochemical and biological parameters (Grzywna & Bronowicka-Mielniczuk, 2020;Shi et al., 2016). The flow of organic and inorganic substances through gutters, upwelling processes, perpendicular mixing of water, and anthropogenic sources like husbandry, monoculture, fishing, energy consumption, and water discharge may affect the water quality (Drira et al., 2017;Tjahjono et al., 2017). ...
Article
Full-text available
Coastal basins are the world’s largest ultimate natural system for productivity and more than 40% of the world’s population prefers to live on the coastline. Thus, the coastal region is of great economic and nutritional importance. The current research study investigates the seasonal deviations in coastal water quality at four different locations along the Gulf of Khambhat, Gujarat, India, for three consecutive seasons (pre-monsoon, monsoon, and post-monsoon). The coastal water samples were collected and analyzed for the water quality in the prescribed study area. As a result, sea surface temperature, salinity, pH, EC, alkalinity, turbidity, salinity, total suspended particles, dissolved oxygen, biological oxygen demand, chemical oxygen demand, chloride, sulfate, and nutrients such as nitrate, nitrite, phosphate, and total organic carbon were investigated at Gulf of Khambhat Region. The samples were collected from four different locations (Ghogha, Dumas, Dahej, and Purna). The multivariate statistical analysis indicates that oxygen, dissolved solids, salinity, nutrients, the natural, and anthropogenic conditions are the major factor that affects water quality. The water quality index was calculated to evaluate the seasonal water quality of GoK. The results revealed that the quality of water was moderate in pre-monsoon, monsoon, and post-monsoon. The findings suggest that anthropogenic disturbances and the development of a variety of activities with increased point and non-point stormwater runoff are pumped directly into the coastal areas which damaged water quality. Therefore, the outcomes of physicochemical research of water quality indicators may be a useful tool for government leaders trying to ensure GoK’s long-term sustainability.
... The number of large and small rivers flowing in coastal waters will transport agricultural waste, industrial waste, and anthropogenic waste from the mainland (Tanjung et al., 2019). These conditions can interrupt the potential in coastal and marine waters as a source of food for the public (Chen et al., 2007;Tjahjono et al., 2017;Drira et al., 2017). The increasing pollution levels in the coastal regions and degradation of marine resources of the country are emerging as important an environmental threat that needs immediate action. ...
Article
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: In Pakistan, marine pollution is a major problem that is caused by the waste from industrial, municipal,agronomy, and oil leak sources. The pollutant loads along with the coastline areas near Karachi is received fromterrestrial contaminants including discharges from Karachi Harbour located on the estuary of the Lyari river. Karachigenerates 472 Million Gallon per Day (MGD) of wastewater out of which only 55 MGD is treated and the rest isdischarged in the sea. The prevailing sewage treatment plants are functioning at reduced capacity due to the insufficienttransmission capacity of interceptors. Water sampling was carried out from the Lyari River and five different selectedcoastal point around Karachi harbour for physicochemical parameters and selected heavy metals. Results show that theKarachi Harbour area is noticeably polluted, whereas; the coastal environment in the vicinity of Karachi is also underthe stress of pollution. High COD and BOD5 values were noticed at the Lyari river samples and the sampling locationsclose to the Lyari river outfall area. The Pb, Cd, Ni, and Hg heavy metals that pollute marine water are found. Thissituation is due to the discharge of mixed effluents of industrial and domestic wastes as well as dredging, cargohandling, dumping of ship waste and other coastal activities. The highest value of pollution observed at KarachiHarbour which is near Lyari river mouth, where the domestic and industrial effluents with organic and inorganic wasteshave a greater influence on the water quality and the marine environment. At present, there is no effective controllingmechanism for industries to treat their waste, nor has any investigation to assess increasing marine pollution beencarried out. As a result, there is an adverse impact on fish habitat and mangroves, corrosion of cargo ships, navalvessels and the residents living in the coastal area. Therefore, the government agencies and industrial sectors shouldwork together to avert marine pollution and attain total environmental sustainability.
... The results of this study state that the Hg, As, and Cd levels in the ESs go beyond one and/or both standards' limits (WHO and NT) in 50% of the samples, as is the case with 25% of samples with the exception of the As element from the SGW. In some Tunisian areas, to mention, the Teboulba region of Monastir (Khaskhoussy and Hachicha 2020), the Skhira region of Sfax (Souidi et al. 2020), Wadi El Bey (Gasmi et al.2016), Sfax, Gabes, and the Ghannouch (Drira et al. 2017), high HMs' concentrations were found (e.g., Cd, Mn, Fe, Cu, Hg, Zn, and Cr) in surface water (rivers) and/or groundwater. As is the case in Maghrebian countries such as the OuedRigh region of South-Eastern Algeria (Benhaddyaet al. 2019), Nil River of North-Eastern Algeria (Krika and Krika 2017), and Saïs Plain of Morocco (Lotfi et al. 2020), the results indicate high concentrations of Cd, Cr, Fe, Cu, and Zn in both surface and groundwater or one of them. ...
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