Open Access

Mercury pollution for marine environment at Farwa Island, Libya

  • Adel A.S. Banana1,
  • R. M. S. Radin Mohamed2 and
  • A. A. S. Al-Gheethi2, 3Email author
Journal of Environmental Health Science and Engineering201614:5

https://doi.org/10.1186/s40201-016-0246-y

Received: 6 May 2015

Accepted: 15 February 2016

Published: 20 February 2016

Abstract

Background

Farwa is an Island in Libya receives petrochemical wastes generated from General Company of Chemical Industries (GCCI) since more than 40 years.

Aim

The present work aimed to determine the concentrations of mercury (Hg+2) in fish, marine plants and sediment collected from Farwa lagoon to evaluate effect of industrial wastewater from GCCI on the marine environment.

Methods

Hundred and twelve samples of fish, pearl oyster, cuttlefish sediments and marine plants were analyzed to determine Hg2+ concentration during the period from January to August 2014 by using Atomic Absorption Spectrometer (AAS).

Results

The highest concentration of Hg2+ was detected in Pinctada radiata (11.67 ± 3.30 μgg 1) followed by Serranus scriba (6.37 ± 0.11 μg g 1) and Epinephelus marginatus (6.19 ± 0.02 μg g 1). About 75 % of marine plants contained the maximum contaminations during the summer season. In fish samples Hg2+ concentrations exceeded the levels provided by international standards.

Conclusions

The fish at Farwa lagoon is heavily contaminated with Hg2+ which may represent a source for mercury poisoning for human.

Keywords

MercuryFishesContaminationFarwa Island

Background

The increasing of industrial activities has led to increase the contamination of environment with several types of pollutants as due to discharge of industrial wastewater into the environment and aquatic system. petrochemicals factors is among various of industrials process which produce heavily contaminated wastewater. In the developed countries the wastewater are treated using advanced technologies such as reverse osmosis, nanotube carbon, adsorption process using different types of adsorbents as well as photo-degradation processes of degradable toxic compounds. Those technologies have high efficiency to remove most toxic substances from wastewater before final disposal into the environment. Others technologies such as multi-walled carbon nanotube/tungsten oxide (MWCNT/WO3) and alumina nano-particles polyamide membrane still under investigation and they exhibited high efficiency for the removal and degrade various types of pollutants based on the lab scale experiments [17].

In the term of heavy metals contamination, the petrochemical industries represent one of the main sources for generation of these toxics into the environment. the adsorption process materials is the most common treatment process to remove heavy metals from wastewater. Recently, some authors focused on improvement this process to be high efficiency. Gupta et al. [8] has combined the magnetic properties of iron oxide with adsorption properties of carbon nanotubes to increase the removal of Cr2+ ions.

Heavy metals are groups of elements with high molecular weights that are not degraded when taken into the body; instead, they accumulate in specific body organs and cause illness. Heavy metals have the potential to disrupt the metabolism and biological activities of many proteins because it can oxidize the sulfhydryl groups [9]. Among several of heavy metals, mercury (Hg2+) is the most toxic element for organisms [1012]. Hg2+ is very toxic pollutant that contaminates fish around the world, therefore fish represent the main source of Hg2+ for human [13]. The studies indicated that mercury accumulation in the oceans correlates with the rising tide of mercury pollution. The most serious Hg2+ poisoning has been occurred due to consumption of Hg2+ contaminated fish and other seafood polluted by industrial wastewater [14]. However, information for mercury contamination of fishes and marine environment in Libya is unavailable; this might due to absence of academic research for more than 40 years. Therefore, the present work aimed to evaluate the concentrations of Hg2+ in fish, sea woods and sediments at Farwa Island, Libya that received petrochemical wastes generated from General Company of Chemical Industries (GCCI) for more than 40 years.

Methods

Study area

Farwa Island is located on the Mediterranean in West Zawya, Libya (33° 04’ N, 1° 50’ E to 33° 08’ N and 11° 32’ E) from Abu- Kamash east to the Tunisian border in the west (Fig. 1). It comprises Farwa lagoon that covering an area of 32 km2 and is the largest lagoon on the Libyan coast. GCCI is located at Abu- Kamash chemical complex. GCCI was opened in 1970s and consist of 3 units that produce 104,000 tonnes/year Ethylene di-chloride, 60, 000 tonnes poly vinyl chloride (PVC), 50,000 tonnes caustic soda and 45,000 tonnes chlorine. In addition to sodium carbonate, sodium hypochlorite and HCl. GCCI has four dumping sites, two of them are located on the west while another two are located on the east.
Fig. 1

Google map of study area, A) GCCI B) site of fish samples collection C) site of marine plant samples collection (100 m); D) site of marine plant samples collection (1000 m); E) site of marine plant samples collection (3000 m); F) site of sediment samples collection (100 m, W); G) site of sediment samples collection (500 m, W); H) site of sediment samples collection (1000 m, W); I) site of sediment samples collection (3000 m, W); J) site of sediment samples collection (100 m, E); K) site of sediment samples collection (500 m, E); L) site of sediment samples collection (1000 m, E); site of sediment samples collection (3000 m, E)

Collection and analysis of samples

Hundred ninety two samples (in triplicate, 3 sample/month) of fishes, oysters, cuttlefish, magnoliophyta plants and sediments were collected from marine environment around of Farwa Island, Libya during the period from January to August 2014. The marine organisms collected samples included ten types of fishes, only one type of oyster and one type of cuttlefish. These samples were collected using local fishermen. Magnoliophyta plant samples were collected from different location around Farwa Lagoon, Zone I (100 m), Zone II (1000 m) and Zone III (3000 m). These locations represent the distance between the sampling point and the factory and they were selected because its very close to GCCI and the possibility to heavy contamination with Hg2+ is high. The samples were transported inside ice box to the laboratory and kept in deep freezer at −20 °C until analysis.

Sample preparation and analysis were carried out according to Bernhard [15]. Liver, muscle, gill, heart, air sac and stomach-intestine were removed before the analysis [16]. Fish samples were homogenized in a blender. Magnoliophyta plants were cut out into small pieces (5 mm in diameter) and then homogenized in a blender. A weight of 10 g of homogenate for each of fish and magnoliophyta plants was digested according to APHA [17]. In briefly; five mL of HNO3 (65 %) and 5 mL of H2SO4 were added into sample placed inside flask (100 mL). The mixture was heated on a hot plate (70–80 °C) for 30 min to the lowest volume (20 mL) before precipitation occurs. The digestion step was continued until light colored, clear solution was observed. The flask walls was washed with distilled water and filtered using Whatman, 125 mm Ø, filter papers (Cat No. 1001 England). The filtrate was transported into a volumetric flask (100 mL) with 10 mL water and mixed thoroughly.

Sediment samples (1 kg) were collected by using grab sampler from eight sites located on the west and east of GCCI. Samples were transported to the laboratory and dried in oven at 50 °C. After that, sediment samples were powdered and passed through 160 μm sieve. The samples packed in paper bags and stored in deep freezer at −20 °C prior to analysis. The mercury was extracted from the samples with 10 mL HNO3/HCl (1:3 v/v) by using a microwave digestion system as described above.

The Hg2+ concentrations in the digested samples were determined by an atomic absorption spectrophotometer (AAS) (Model P.E.A ANALYST 100, HGA-800 and MHS-10, Perkin Elmer, USA).

The concentrations of heavy metals was calculated (μg g−1) using Eqs. (1)
$$ MetalConcentration=A\times B/C $$

Where

A = concentrations of metals in digested solution μg g −1

B = final volume of digested solution mL

C = sample size, gram

Data analysis

The data were not normally distributed, therefore, they were log transformed and subjected to parametric statistics. The differences in Hg2+ concentrations of samples investigated were tested by ANOVA. The statistical analyses was performed SPSS (version 11.5).

Results and discussion

The present study investigated the mercury contamination of marine environment included fishes, oysters, cuttlefish, magnoliophyta plants and sediments at Farwa Island, Libya that are received industrial wastewater generated from GCCI since 40 years ago. The concentration of mercury at this place has not reported before, thus the current work was conducted to evaluate the effect of petrochemical wastewater on the environment. The results revealed that the Hg2+ concentration differed significantly (p < 0.05) during the period of study (Table 1). These variables may be due to the climatic conditions of the area, winter season extends from November to March and is generally cold and rainy with unstable winds blowing from different directions which lead to cause dilution of Farwa lagoon, while summer season (May to September) is rather hot and dry [18]. The mean of Hg2+ concentrations in fish, oysters and cuttlefish samples collected during the period study are presented in Table 2. It can be noted that the Hg2+ concentrations ranged from 3.13 ± 1.5 μg g−1 in Serranus scriba to 0.34 ± 0.33 μg g−1 in Sciaena umbra. The distributions of Hg2+ concentrations for each species in the period from January to August 2014 are depicted in Fig. 2. It shown that the highest concentration of Hg2+ was detected in Pinctada radiata (11.67 ± 3.30 μgg−1) in August, followed by Serranus scriba (6.37 ± 0.11 μg g−1) in July and Epinephelus marginatus (6.19 ± 0.02 μg g−1) in February. The Serranus scriba have high concentration of Hg2+ during the study period from January to July followed by Epinephelus marginatus, the average was 2.83 vs. 2.18 μg g-1. The lowest Hg2+ concentrations were detected in Pagrus pagrus (0.001 μg g−1) and Sciaena umbra (0.01 μg g−1). Both types contained the lowest average concentrations during the period of study (0.33 and 0.36 μg g−1 respectively). Lithognathus mormyrus has the highest Hg (3.59 ± 0.19 μg g−1) among the fish samples collected in April, whereas Oedalechilus labeo has the highest Hg (3.59 ± 0.01 μg g−1) among the fish samples collected in May. In June, the highest Hg2+ was determined in Lithognathus mormyrus (4.97 ± 0.04 μg g−1).
Table 1

ANOVA Analysis of Hg2+ concentrations in different fish samples during the period of study from January to August 2014

Sample

 

Sum of Squares

df

Mean Square

F

Sig.

Serranus scriba

Between groups

54.369

7

7.767

1257.814

.000

Within groups

.099

16

.006

  

Total

54.468

23

   

Oedalechilus labeo

Between groups

28.478

7

4.068

2697.193

.000

Within groups

.024

16

.002

  

Total

28.502

23

   

Diplodus vulgaris

Between groups

6.588

7

.941

1146.640

.000

Within groups

.013

16

.001

  

Total

6.602

23

   

Dicentrarchus labrax

Between groups

4.697

7

.671

712.616

.000

Within groups

.015

16

.001

  

Total

4.712

23

   

Lithognathus mormyrus

Between groups

70.353

7

10.050

2138.378

.000

Within groups

.075

16

.005

  

Total

70.428

23

   

Epinephelus marginatus

Between groups

99.308

7

14.187

16690.375

.000

Within groups

.014

16

.001

  

Total

99.321

23

   

Sarpa salpa

Between groups

11.577

7

1.654

301.838

.000

Within groups

.088

16

.005

  

Total

11.664

23

   

Sciaena umbra

Between groups

3.448

7

.493

467.260

.000

Within groups

.017

16

.001

  

Total

3.465

23

   

Pagrus pagrus

Between groups

3.373

7

.482

98.591

.000

Within groups

.078

16

.005

  

Total

3.451

23

   

Caranx crysos

Between groups

5.237

7

.748

949.947

.000

Within groups

.013

16

.001

  

Total

5.249

23

   

Pinctada radiata

Between groups

310.444

7

44.349

6809.846

.000

Within groups

.104

16

.007

  

Total

310.548

23

   

Sepia officinalis

Between groups

2.703

7

.386

639.161

.000

Within groups

.010

16

.001

  

Total

2.713

23

   
Table 2

Hg2+ concentrations in Fishes collected from Farwa lagoon, Libya which received petrochemical wastes from General Company of Chemical Industries (GCCI), (±SD represent the standard division from the mean, n = 24 for each sample)

Sample No.

Family name

English name

Science name

Hg concentration (μg g−1)

1

Serranidae

Painted comber

Serranus scriba

3.13 ± 1.5

2

Mugilidae

Boxlip Mullet

Oedalechilus labeo

1.4 ± 1.1

3

Sparidae

Common Two-Banded Seabream

Diplodus vulgaris

1.4 ± 0.53

4

Moronidae

European seabass

Dicentrarchus labrax

0.89 ± 0.45

5

Sparidae

Striped sea bream

Lithognathus mormyrus

1.5 ± 0.7

6

Serranidae

Dusky Grouper

Epinephelus marginatus

1.9 ± 2.0

7

Sparidae

Salema

Sarpa salpa

0.99 ± 0.71

8

Sciaenidae

sculpin

Sciaena umbra

0.34 ± 0.33

9

Dentex macrophthalmus

Red porgy

Pagrus pagrus

0.39 ± 0.38

10

Carangidae

blue runner

Caranx crysos

0.78 ± 0.48

11

Oyster

Rayed Pearl Oyster

Pinctada radiata

2.3 ± 3.6

12

Cuttlefish

common cuttlefish

Sepia officinalis

0.63 ± 0.34

Fig. 2

Seasonal distribution of Hg2+ concentrations in fish, oysters and cuttlefish samples collected from Farwa lagoon, Libya; a) Serranus scriba; b) Oedalechilus labeo, c) Diplodus vulgaris; d) Dicentrarchus labrax; e) Lithognathus mormyrus; f) Epinephelus marginatus; g) Sarpa salpa; h) Sciaena umbra; i) Pagrus pagrus; j) Caranx crysos; k) Pinctada radiate; l) Sepia officinalis

The analysis for association between Hg2+ concentrations in fish, oysters as well as cuttlefish samples and months indicated that the concentration of Hg2+ in Serranus scriba, Dicentrarchus labrax, Sciaena umbra and Pinctada radiata associated significantly (p < 0.05) to the seasons with R2 0.64, 0.24, 0.21 and 0.34 respectively (Table 3). The Hg2+ concentrations in magnoliophyta plants are presented in Table 4. It can be noted that the maximum concentration was detected in the samples collected from place near of GCCI (100 m). The highest concentrations were determined in samples collected during April, where, 2.33 ± 0.60, 1.44 ± 0.42 and 0.96 ± 0.12 μg g−1 were determined in samples collected from zone I, II and III respectively. The lowest Hg2+ was recorded in samples collected from zone III (0.02 ± 0.00 μg g−1) during January. In comparison with the study conducted by Pergent-Martini [19] which was carried out on the mercury contamination in the Posidonia oceanica Collected from mediterranean sea. It can be noted that the Hg2+ concentrations in this study was quite high. There would be due to dispose of wastewater generated from GCCI into the sea without treatment process since 40 years ago.
Table 3

Measures of association between Hg2+ concentrations in fish, oysters as well as cuttlefish samples and months

Sample*month

R

R Squared

Eta

Eta Squared

Significance (p value)

Serranus scriba

0.80

0.64

0.99

0.99

0.01

Oedalechilus labeo

−0.228

0.05

1.00

0.99

0.14

Diplodus vulgaris

0.327

0.11

0.99

0.99

0.06

Dicentrarchus labrax

0.493

0.24

0.99

0.99

0.01

Lithognathus mormyrus

0.191

0.04

0.99

0.99

0.18

Epinephelus marginatus

−0.173

0.03

1.00

1.00

0.21

Sarpa salpa

−0.068

0.01

0.99

0.99

0.38

Sciaena umbra

0.454

0.21

0.99

0.99

0.01

Pagrus pagrus

0.215

0.05

0.98

0.98

0.16

Caranx crysos

0.006

0.00

0.99

0.99

0.45

Pinctada radiata

0.587

0.34

1.00

1.00

0.01

Sepia officinalis

−0.188

0.04

0.99

0.99

0.19

Table 4

Hg2+ concentrations in magnoliophyta plant samples collected from different distance of GCCI at Farwa lagoon, Libya (±SD represent the standard division from the mean, n = 3 for each sample per month)

Sample/month

Hg2+ concentrations (μg g−1)

Zone I (100 m)

Zone II (1000 m)

Zone III (3000 m)

1

0.82 ± 0.20

0.93 ± 0.13

0.02 ± 0.00

2

0.39 ± 0.12

0.50 ± 0.08

0.10 ± 0.09

3

2.10 ± 0.91

0.57 ± 0.16

0.82 ± 0.20

4

2.33 ± 0.60

1.44 ± 0.42

0.96 ± 0.12

5

1.06 ± 0.18

0.79 ± 0.12

0.75 ± 0.19

6

1.00 ± 0.13

1.38 ± 0.92

0.54 ± 0.20

7

0.87 ± 0.30

0.25 ± 0.09

0.64 ± 0.21

8

1.40 ± 0.42

1.07 ± 0.13

0.71 ± 0.15

The present study revealed that the concentrations of Hg2+ in all types of fish samples were more than the standards limits recommended by FDA and FAO-WHO [20, 21]. According to U.S. EPA [22], Hg2+ should be less than 0.3 μg g−1 wet fish muscle tissue for protection of human health. However, Zaza et al. [13] reported that the minimum level of Hg2+ is 0.5 μg g−1 for fish species. In the present study, the minimum concentration of Hg2+ was 1 μg g−1 in Pagrus pagrus. Fish consumption is one of the major factors of Hg2+ intake for humans [23, 24]. Hg2+ is very dangerous for pregnant woman because mercury is most harmful to developing foetuses, infants, and young children.

High Hg2+ concentration was detected in sediment samples collected from the West of GCCI than those collected from the East. However, both sites contain high concentration of Hg2+. The Hg2+ concentration decreased significantly (p < 0.05) as the site distance from GCCI, the maximum Hg2+ was noted in sediment samples taken from the west (100 m from GCCI) where 11.14 ± 4.11 μg g−1 was recorded in April 2014 (Table 5). Among the sediment samples collected from the east, the samples taken in June contain 4.67 ± 1.62 μg Hg2+ g−1. The pollution of environmental area around GCCI represent a serious problem due to that the surrounding areas are used for agricultural purpose such as for Grapes, olives and almonds. More than 1500 people are living around the GCCI.
Table 5

Hg2+ concentrations in sediment samples collected from the west and east GCCI during the period January to August 2014 (±SD represent the standard division from the mean, n = 3 for each sample per month)

Sediments sample/month

Hg2+ Concentration (μg g−1)

West of GCCI

East of GCCI

Control

<100 m

500 m

1000 m

3000 m

100 m

500 m

1000 m

3000 m

Zwara city (20 km)

1

3.54 ± 1.10

1.38 ± 0.14

1.09 ± 0.04

0.64 ± 0.32

1.96 ± 1.01

0.55 ± 0.06

0.03 ± 0.0

0.01 ± 0.0

0.001 ± 0.0

2

6.74 ± 3.14

4.06 ± 1.81

1.07 ± 0.52

0.32 ± 0.19

1.55 ± 0.71

1.12 ± 0.24

0.75 ± 0.18

0.01 ± 0.0

0.001 ± 0.0

3

4.58 ± 1.43

3.04 ± 0.93

0.06 ± 0.09

0.02 ± 0.01

2.07 ± 0.91

0.75 ± 0.18

0.05 ± 0.01

0.001 ± 0.0

0.001 ± 0.0

4

11.14 ± 4.11

2.64 ± 0.83

1.95 ± 0.31

0.56 ± 0.08

3.65 ± 1.04

1.47 ± 0.91

0.01 ± 0.0

0.001 ± 0.0

0.001 ± 0.0

5

8.50 ± 2.84

5.07 ± 2.81

1.01 ± 0.41

0.75 ± 0.11

3.12 ± 1.11

0.06 ± 0.01

0.003 ± 0.0

0.001 ± 0.0

0.001 ± 0.0

6

2.46 ± 1.31

3.65 ± 1.71

0.95 ± 0.71

0.07 ± 0.22

4.67 ± 1.62

1.5 ± 0.46

0.001 ± 0.0

0.01 ± 0.0

0.003 ± 0.0

7

5.21 ± 2.28

4.06 ± 1.93

0.50 ± 0.01

0.43 ± 0.17

2.13 ± 0.98

0.04 ± 0.0

0.01 ± 0.0

0.002 ± 0.0

0.001 ± 0.0

8

1.56 ± 0.73

3.25 ± 0.88

0.36 ± 0.03

0.05 ± 0.0

3.17 ± 0.51

1.45 ± 0.29

0.003 ± 0.0

0.002 ± 0.0

0.001 ± 0.0

Farwa Island has high fishery production, but this Island had been exposed for heavy pollution due to GCCI for more than 40 years. Farwa Island is the most important coastal and marine site in western Libya, in terms of its high marine and coastal biodiversity based on several surveys and studies during the last years. However, no information was recorded according to mercury pollution. This region is characterized by an exceptional importance in terms of fish and artisanal fisheries, aquaculture, sea birds, sea grass meadows, land/seascape features and, above all, as one of the few regions in the Mediterranean to experience active tidal movements. In addition to some endangered species which makes it an important area for larva and juvenile protection. In the term of biodiversity, Farwa has many economically important species and certain endangered species are recognized [18].

In the term of toxic pollutants in industrial wastewater and their environmental impact and health effect, the sea water around of GCCI should be treated to remove of Hg2+ ions. Variety of biological and physico-chemical methods for wastewater treatment has been developed. Among those technologies, reverse osmosis, activated carbon, advanced oxidation, alumina-coated carbon nanotubes, tire derived carbons, porous carbon, carbon nanotubes and fullerene and CNT/magnesium oxide composite have exhibited high efficiency for removal of heavy metals from different aqueous solution [2533].

Conclusions

It can be concluded that the heavily contamination of fish, oysters as well as cuttlefish in marine environment around GCCI represent a main source for food poisoning among peoples living in this area. Therefore, the contaminated area should be treated to prevent health risk associated with mercury contamination.

Declarations

Acknowledgments

The authors would like to thank Badu Society for Protection Marine Biology and Wild for allow us to use their laboratories. In addition, to express their appreciations to the Universiti Tun Hussein Onn Malaysia (UTHM), School of Civil and Environmental Engineering for Postdoctoral Fellowship to Adel Al-Gheethi.

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Environment Engineering Department, Subrata College, University of Zawia
(2)
Faculty of Civil & Environment Engineering, UTHM
(3)
High Institute of health sciences

References

  1. Mittal A, Kaur D, Malviya A, Mittal J, Gupta VK. Adsorption studies on the removal of coloring agent phenol red from wastewater using waste materials as adsorbents. J Coll Interface Sci. 2009;337:345–54.View ArticleGoogle Scholar
  2. Mittal A, Mittal J, Malviya A, Kaur D, Gupta VK. Decoloration treatment of a hazardous triarylmethane dye, Light Green SF (Yellowish) by waste material adsorbents. J Coll Interface Sci. 2010;342:518–27.View ArticleGoogle Scholar
  3. Mittal A, Mittal J, Malviya A, Gupta VK. Removal and recovery of Chrysoidine Y from aqueous solutions by waste materials. J Coll Interface Sci. 2010;344:497–507.View ArticleGoogle Scholar
  4. SaleH TA, Gupta VK. Functionalization of tungsten oxide into MWCNT and its application for sunlight-induced degradation of rhodamine B. J Coll Interface Sci. 2010;362:337–44.View ArticleGoogle Scholar
  5. Saleh TA, Agarwal S, Gupta VK. Synthesis of MWCNT/MnO2 and their application for simultaneous oxidation of arsenite and sorption of arsenate. Appl Catal B Environ. 2011;106:46–53.Google Scholar
  6. Saleh TA, Gupta VK. Synthesis and characterization of alumina nano-particles polyamide membrane with enhanced flux rejection performance. Sep Pur Technol. 2012;89:245–51.View ArticleGoogle Scholar
  7. Vinod K, Gupa VK, Jain R, Nayak A, Agarwal S, Shrivastava M. Removal of the hazardous dye—Tartrazine by photodegradation on titanium dioxide surface. Mat Sci Eng: C. 2011;31:1062–7.View ArticleGoogle Scholar
  8. Gupta VK, Nayak A. Cadmium removal and recovery from aqueous solutions by novel adsorbents prepared from orange peel and Fe2O3 nanoparticles. Chem Eng J. 2012;180:81–90.View ArticleGoogle Scholar
  9. Gupta VK, Agarwal S, Saleh TA. Chromium removal by combining the magnetic properties of iron oxide with adsorption properties of carbon nanotubes. Water Res. 2011;45:2207–12.View ArticleGoogle Scholar
  10. Epstein E: Health issues related to beneficial use of biosolids. In: 16th Annual Residuals and Biosolids Management Conference of the Water Environment Federation, Texas. 2002, p. 9.Google Scholar
  11. Clarkson TW. The toxicology of mercury. Crit Rev Clin Lab Sci. 1997;34:369–403.View ArticleGoogle Scholar
  12. Magos L. Physiology and toxicology of mercury. Metal Ions Biol Sys. 1997;34:321–70.Google Scholar
  13. Langford N, Ferner R. Toxicity of mercury. J Hum Hypertens. 1999;13(10):651–6.View ArticleGoogle Scholar
  14. Zaza S, de Balogh K, Palmery M, Pastorelli AA, Stacchini P. Human exposure in Italy to lead, cadmium and mercury through fish and seafood product consumption from Eastern Central Atlantic Fishing Area. J Food Comp Anal 2015, (Accepted). doi: 10.1016/j.jfca.2015.01.007.
  15. Harada M. Minamata disease: methylmercury poisoning in Japan caused by environmental pollution. Crit Rev Toxicol. 1995;25:1–24.View ArticleGoogle Scholar
  16. Bernhard M. Manual of methods in aquatic environment research, part 3: sampling and analyses of biological material. Rome: FAO Fish Tech Paper No. 158, UNEP; 1976.Google Scholar
  17. Öztürk M, Özözen G, Minareci O, Minareci E. Determination of heavy metals in fish, water and sediments of Avsar dam lake in Turkey, Iran. J Environ Health Sci Eng. 2009;6(2):73–80.Google Scholar
  18. APHA. Standard methods for the examination of water and wastewater. 20th ed. Washington, DC: American Public Health Association; 1998.Google Scholar
  19. Haddoud DA, Rawag AA. Marine protected areas along Libyan coast; In Report of the MedSudMed expert consultation on marine protected areas and fisheries management. MedSudMed Technical Documents No. 3 Rome (Italy), June 2007 GCP/RER/010/ITA/MSM-TD-03. 2007.Google Scholar
  20. Pergent-Martini C. Posidonia oceanica: a biological indicator of past and present mercury contamination in the mediterranean sea. Marine Environ Res. 1998;45:101–11.View ArticleGoogle Scholar
  21. Hall RA, Zook EG, Meaburn GM. National Marine Fisheries Service. Survey of trace elements in the fishery resource. U.S. Department of Commerce National Oceanic and Atmospheric Administration National Marine Fisheries Service. 1978.Google Scholar
  22. Voegborlo RB, Methnani AME, Abedin MZ. Mercury, cadmium and lead content of canned Tuna fish. Food Chem. 1999;67(4):341–5.View ArticleGoogle Scholar
  23. EPA US. Water quality criterion for the protection of human health-methylmercury. Office of Science and Technology, Office of Water, USEPA: U.S. Environmental Protection Agency; 2001.Google Scholar
  24. Santos ECO, Camara VM, Jesus IM, Brabo ES, Loureiro ECB, Mascarenhas AFS, Fayal KF, Sa Filho GC, Sagica FES, Lima MO, Higuchi H, Silveira IM. A contribution to the establishment of reference values for total mercury levels in hair and fish in Amazonia. Environ Res. 2002;90:6–11.View ArticleGoogle Scholar
  25. Yasutake A, Matsumoto M, Yamaguchi M, Hachiya N. Current hair mercury levels in Japanese: survey in five districts. Tohoku J Exper Med. 2003;199:161–9.View ArticleGoogle Scholar
  26. Gupta VK VK, Srivastava SK, Mohan D, Sharma S. Design parameters for fixed bed reactors of activated carbon developed from fertilizer waste for the removal of some heavy metal ions. Waste Manag. 1997;17:517–22.View ArticleGoogle Scholar
  27. Gupta VK, Agarwal S, Saleh TA. Synthesis and characterization of alumina-coated carbon nanotubes and their application for lead removal. J Hazar Mat. 2011;185:17–23.View ArticleGoogle Scholar
  28. Saleh TA, Gupta VK. Photo-catalyzed degradation of hazardous dye methyl orange by use of acomposite catalyst consisting of multi-walled carbon nanotubes and titanium dioxide. J Colloid Interface Sci. 2012;371:101–6.View ArticleGoogle Scholar
  29. Saleh TA, Gupta VK. Processing methods, characteristics and adsorption behavior of tire derived carbons: A review. Adv Colloid Interface Sci. 2014;211:93–101.View ArticleGoogle Scholar
  30. Gupta VK, Kumar R, Nayak A, Saleh TA, Barakat MA. Adsorptive removal of dyes from aqueous solution onto carbon nanotubes: A review. Adv Colloid Interface Sci. 2013;193–194:24–34.View ArticleGoogle Scholar
  31. Gupta VK, Ali A, Saleh TA, Nayak A, Agarwal S. Chemical treatment technologies for waste-water recycling—an overview. RSC Adv. 2012;2:6380–8.View ArticleGoogle Scholar
  32. Gupta VK, Saleh TA. Sorption of pollutants by porous carbon, carbon nanotubes and fullerene- An overview. Environ Sci Poll Res. 2013;20:2828–43.View ArticleGoogle Scholar
  33. Saleh TA, Gupta VK. Column with CNT/magnesium oxide composite for lead(II) removal from water. Environ Sci Pollut Res Int. 2012;19:1224–8.View ArticleGoogle Scholar

Copyright

© Banana et al. 2016

Advertisement