Distribution of heavy metals in water, particulate matter and sediments of Gediz River (Eastern Aegean).

The present paper is the first document of heavy metal levels in surficial sediment, water and particulate matter of the Gediz River collected from five different sites in August, October 1998, February, June 1999. The present work attempts to establish the status of distribution and environmental implications of metals in the sediment, water and particulate matter and their possible sources of derivation. The concentrations of mercury ranged 0.037-0.81, 120-430; lead 0.59-1.5, 190-8,100; copper 0.24-1.6, 30-180; zinc 0.19-2.9, 10-80; manganese 30-170, 20-490; nickel 0.39-9.0, 100-510; iron 1.3-687, 100-6,200 microg/l in water and particulate matter, respectively. The maximum values in water were generally obtained in summer periods due to industrial and agricultural activities at Muradiye. The particulate metal concentrations also generally showed increased levels from the upper Gediz to the mouth of the river. Calculation of metal partition coefficients shows that the relative importance of the particulate and the water phases varies in response to water hydrochemistry and suspended solid content, but that most elements achieve a conditional equilibrium in the Gediz River. The metals ranged between Hg: 0.25-0.49, Cr: 59-814, Pb: 38-198, Cu: 15-148, Zn: 34-196, Mn: 235-1,371, Ni: 35-175, and Fe: 10,629-72,387 mg/kg in sediment. The significant increase of metals found in Muradiye suggested a pollution effect, related to anthropogenic wastes. Also, relatively high concentrations of Ni and Mn occurred in sampling site upstream, due to geochemical composition of the sediments. Maximum values of contamination factor for metals were noticed for sediment of Muradiye. The sampling stations have very high degree of contamination indicating serious anthropogenic pollution.

Heavy metal contaminants in Red Pandora (Pagellus erythrinus) tissues from the Eastern Aegean Sea, Turkey.

Heavy metal contents were investigated in different organ tissues of Red Pandora (Pagellus erythrinus) from the eastern Aegean Sea between May 1996 and July 1998. The concentrations of mercury in the muscle tissue ranged between 16 and 716, in liver 125-5451, in gonad 2.0-1858; cadmium in muscle nd-9.6, in liver 1.4-2245, in gonad nd-192; lead in muscle nd-1397, in liver 112-8311, in gonad nd-2927; zinc in muscle 1352-6693, in liver 2710-78705, in gonad 7273-168655; copper in muscle nd-383, in liver nd-21986, in gonad nd-20499 (microg/kg wet weight). The highest concentrations were generally found in the Southern Aegean Sea. All metal levels in muscle tissues are lower than the limits of European Dietary Standards and Guidelines. The metals ratios between liver and muscle indicated that the liver accumulated higher levels of metals than the muscle tissues. The bioaccumulation factor (BAFs) of metals was measured in muscle, liver and gonads. BAFs among the analysed elements showed the descending orders as Zn>Cu>Cd>Pb for muscle and gonads and Cd>Zn>Cu>Pb for liver.

Assessment of marine pollution in Izmir Bay: nutrient, heavy metal and total hydrocarbon concentrations.

Izmir Bay (western Turkey) is one of the great natural bays of the Mediterranean. Izmir is an important industrial and commercial centre and a cultural focal point. The main industries in the region include food processing, oil, soap and paint production, chemical industries, paper and pulp factories, textile industries and metal processing. The mean concentrations showed ranges of 0.01-0.19 and 0.01-10 microM for phosphate, 0.10-1.8 and 0.12-27 microM for nitrate+nitrite, and 0.30-5.8 and 0.43-39 microM for silicate in the outer and middle-inner bays, respectively. The TNO(x)/PO(4) ratio is significantly lower than the Redfield's ratio and nitrogen is the limiting element in the middle-inner bays. Diatoms and dinoflagellates were observed all year around in the bay and are normally nitrogen limited. Metal concentrations ranged between Hg: 0.05-1.3, Cd: 0.005-0.82, Pb: 14-113 and Cr: 29-316 microg g(-1) in the sediments. The results showed significant enrichments during sampling periods from Inner Bay. Outer and middle bays show low levels of heavy metal enrichments except estuary of Gediz River. The concentrations of Hg, Cd and Pb in the outer bay were generally similar to the background levels from the Mediterranean. The levels gradually decreased over the sampling period. Total hydrocarbons concentrations range from 427 to 7800 ng g(-1) of sediments. The highest total hydrocarbon levels were found in the inner bay due to the anthropogenic activities, mainly combustion processes of traffic and industrial activities. The concentrations of heavy metals found in fish varied for Hg: 4.5-520, Cd: 0.10-10 and Pb: 0.10-491 microg kg(-1) in Izmir Bay. There was no significant seasonal variation in metal concentrations. An increase in Hg concentration with increasing length was noted for Mullus barbatus. A person can consume more than 2, 133 and 20 meals per week of fish in human diet would represent the tolerable weekly intake of mercury, cadmium and lead, respectively, in Izmir Bay. Heavy metal levels were lower than the results in fish tissues reported from polluted areas of the Mediterranean Sea.

Monitoring of eutrophication and nutrient limitation in the Izmir Bay (Turkey) before and after Wastewater Treatment Plant.

The distribution of inorganic nutrients and phytoplankton chlorophyll-a was investigated and N/P ratios were determined in Izmir Bay during 1996-2001. The average concentrations showed ranges of 0.01-0.19 and 0.01-10 microM for phosphate-phosphorus; 0.11-1.8 and 0.13-27 microM for (nitrate+nitrite)-nitrogen, 0.30-4.1 and 0.50-39 microM for silicate and 0.02-4.3 and 0.10-26 microg l(-1) for chlorophyll-a in the outer and middle-inner bays, respectively. The results are compared with the values obtained from the relatively unpolluted waters of the Aegean Sea. The N/P ratio is significantly lower than the assimilatory optimal (N/P=15:1) in conformity with Redfield's ratio N/P=16:1. Nitrogen is the limiting element in the Izmir Bay. Phosphate, which originates from detergents, is an important source for eutrophication in the bay, especially in the inner bay. In early 2000, a Wastewater Treatment Plant (WTP) began to treat domestic and industrial wastes. This plant treats the wastes about 60% capacity between 2000 and 2001. The sampling periods cover before and after treatment plant. Although the capacity of wastewater plant is sufficient for removal of nitrogen from the wastes, it is inadequate for removal of phosphate. This is also in accordance with the decreasing N/P ratios observed during 2000-2001 (after WTP) in the middle-inner bays.

Trace metal and organochlorine residue levels in red mullet (Mullus barbatus) from the eastern Aegean, Turkey.

The levels of trace metals and organochlorine residue were determined in red mullet (Mullus barbatus) in the framework of a MED-POL II Project for the Aegean Sea during 1994-1998. Samples were analyzed seasonally from July 1994 to January 1998. The concentrations of trace metals found varied with Hg: 16-200 microg kg(-1), Cd: 0.57-4.5 microg kg(-1) and Pb: 40-207 microg kg(-1) wet weight. The order of trace metal concentrations found in Mullus barbatus was Pb > Hg > Cd. Correlation coefficients were calculated between Hg, Cd, and Pb concentrations and fork lengths to be Hg: 0.5852, Cd: -0.081, Pb: 0.5823, respectively. Cadmium levels are lower than the results in fish tissues reported from Mediterranean regions. The results of organochlorine residues measured varied between Aldrin: 0.10 and 0.61 microg kg(-1), t-DDD: 0.86 and 4.5 microg kg(-1) and t-DDE: 10 and 18 microg kg(-1) wet weight. Correlation coefficients for measured organochlorine residues and fork lengths are Aldrin: 0.6422, t-DDD: 0.2237 and t-DDE: 0.5484. The levels of mercury, lead and organochlorine residues are similar to the results in fish from Mediterranean countries.