Assessment of heavy metals concentration in holothurians, sediments and water samples from coastal areas of Pakistan (Northern Arabian Sea)

Objective: To determine heavy metal concentrations in holothurians (Holothuria arenicola, Holothuria pardalis, Holothuria verrucosa, Holothuria atra, Ohshimella ehrenbergii, Holothuria cinerascens, Stolus buccalis and Holothuria leucospilota), sediments and sea water samples from both Buleji and Sunehri coasts bordering Northern Arabian Sea during January to December 2014 and to assess the level of bioaccumulation using bioaccumulation factors. Methods: Fe, Mn, Zn, Cu, Cd and Pb levels were determined by Perkin Elmer AAnalyst 700 Atomic Absorption Spectrophotometer. Biota concentration factor (BCF) and biota sediment accumulation factor (BSAF) were also calculated. Results: The mean concentrations of heavy metals in body wall of sea cucumber ranged from 0.11 to 2.67, 0.43 to 8.93, 14 to 73, 0.76 to 7.12, 0.52 to 3.02 and 11 to 46 μg/g dry wright for Cd, Cu, Fe, Mn, Pb and Zn, respectively. The greatest biota-sediment bioaccumulation factor (BSAF) value for Zn (3.29) was observed in H. leucospilota at Buleji during pre-monsoon, indicating the species as microconcentrator. The BSAF values for Cd in sea cucumber ranged from 0.042 to 1.492. Conclusions: The results suggested that the studied sea cucumber species ranged from being microconcentrators to deconcentrators. The BSAF values of Cu, Fe, Mn and Pb were low, indicating the species as deconcentrators. Zn in all species from Sunehri coast is 'very bioaccumulative' (BCF > 5000) during all sampling periods. Cu, Fe, Mn and Pb can be considered 'bioaccumulative' (BCF < 5000).

Heavy metal levels in different sizes and tissues of Drepane longimana (Bloch & Schneider, 1801) from Arabian Sea

Objective: To determine the levels of six heavy metals in the liver and edible tissues of different sizes of Drepane longimana collected at Karachi fish harbor of Pakistan during fisheries seasons in 2016. Methods: The concentrations of iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), lead (Pb) and cadmium (Cd) were carried out using Atomic Absorption Spectrophotometer (AAS, Aanalyst 700). Results: In muscle and liver tissues, Fe is detected in highest concentrations, followed by Zn, Cu, Mn, Cd and Pb. Concentrations of Cd and Pb of some individuals were not detected in the edible tissues. Large differences in these metal concentrations were observed between different tissues within each size of fish except Mn in 24–28 cm sizes. The liver of Drepane longimana accumulates significant higher levels of metals than those in the edible tissues. Conclusions: Based on the results of this study, the bioaccumulation of metals in the muscles of concertina fish did not exceed the permissible limits set for heavy metals by European Commission Regulation, Food and Agriculture Organization and Turkish Food Codex. It could be concluded that there is no risk in consumption of Concertina fish from Karachi fish harbor of Pakistan in 2016.

Seasonal variations of heavy metal concentration in Sardinella sindensis(Day,1878)from Balochistan coast

Objective:To determine Fe,Cu,Zn,Pb and Cd concentrations in muscle of sind sardinella[Sardinella sindensis(S.sindensis)]from Balochistan coast,Pakistan.Methods:S.sindensis were collected from Balochistan coast,Pakistan,at autumn inter monsoon,north east monsoon,spring inter monsoon and south west monsoon during October 2005-September 2006.All samples were analyzed for Fe,Cu,Zn,Pb and Cd by AAnalyst 700 flame atomic absorption spectrophotometer.Results:Generally,S.sindensis caught from Balochistan coast showed the accumulation level of Fe[(16.88±5.60)μg/g],Cu[(2.74±1.89)μg/g],Cd[(0.29±0.25)μg/g],Zn[(4.29±2.31)μg/g]and Pb[(0.24±0.24)μg/g]in the muscle tissues.Conclusions:The metal concentrations in fish from Balochistan coast observed in this study were lower than the limit values.Therefore,all metal accumulations in S.sindensis have to be monitored continuously,especially in this region.

Physicochemical parameters and seasonal variation of coastal water from Balochistan coast,Pakistan

Objective:To determine common physico-chemical parameters of coastal water.Methods:Physicochemical properties of water were determined according to the standards of the American Public Health Association.Generally,all those parameters were recorded a small variation between stations.The variation in physico-chemical parameters like salinity,temperature,dissolved oxygen and pH at Gwadar(Coastal water of Balochistan)were recorded.Results:The range of air temperature of coastal water of Balochistan during 2004 and 2006 varies from 25℃to 37℃,water temperature ranged from 15.00℃to 33.00℃,pH ranged from 7.08 to 8.95,salinity ranged from 37.4‰to 41.3‰and dissolved oxygen ranged from 5.32 to 8.67 mg/L.Conclusions:Results showed that these parameters of Balochistan coast of Pakistan is not dangerous for marine habitat and the use of these parameters in monitoring programs to assess ecosystem health has the potential to inform the general public and decision-makers about the state of the coastal ecosystems.To save this vital important habitat,the government agencies and scientists should work with proper attention.