Organochlorine compounds in surface sediments from the northern coast of Cyprus, Eastern Mediterranean: Levels, possible sources and potential risk.

Organochlorines (OCs) were determined in sediments collected from different regions of northern coast of Cyprus. The OCPs and Aroclors had a wide range from 2.78 to 306 and 15 to 325ngg(-1), respectively. The highest level was found at Yedi Dalga site. DDE was the most abundant compound. The ratios of metabolites to parent DDT showed that DDTs were derived mostly from the aged and weathered inputs. Comparing our results with the previous studies showed that POPs in sediments were found to be lower than those in samples for Mediterranean and Black Sea coasts. The SQG implied that, Aroclor1254 exceeded the TEL values, showing that adverse biological effects are expected occasionally at some of the sediment samples. DDTs were dominant and more ecotoxicological concern in the northern Cyprus. Altogether, it may be summarized that DDTs will impose ecologically hazardous impacts in the sedimentary environment at the present.

Assessment of heavy metal contamination in Hediste diversicolor (O.F. Müller, 1776), Mugil cephalus (Linnaeus, 1758), and surface sediments of Bafa Lake (Eastern Aegean).

In the present study, the bioaccumulation of six heavy metals (Cd, Cr, Cu, Hg, Pb, and Zn) in Hediste (Nereis) diversicolor (O.F. Müller, 1776) and also in the muscle and liver of Mugil cephalus (Linnaeus, 1758) collected from seven stations in the Bafa Lake was investigated. Sediment samples were also collected in each site to assess heavy metal levels and to provide additional information on pollution of the lake. The mean concentrations of heavy metals in sediment, H. diversicolor, and muscle and liver of the fish were found to be in the magnitude of Cr>Pb>Zn>Cu>Cd>Hg, Zn>Cu>Cr>Pb>Hg>Cd, Zn>Cu>Pb>Cr >Hg>Cd, and Cu>Zn>Cr>Cd>Pb>Hg, respectively. Hg, Cu, and Zn in H. diversicolor and Hg and Zn in muscle and also Hg, Cd, Cu, and Zn in liver of fish accumulated in a higher degree than in sediment. There was no clear relationship between metal concentrations in sediments, polychaetes, and fish, except Cr. According to international criteria and Turkish regulations, Pb and Zn values in edible muscle of the fish collected from stations S6 and S5 exceeded the food safety limits, respectively. The results of this study suggest that these sentinel species can be considered as good anthropogenic biological indicators for heavy metal pollution along the Bafa Lake.

Temporal and spatial biomonitoring of heavy metals in eastern Aegean coastal waters using Amphibalanus amphitrite.

This biomonitoring study presents the spatial and temporal distributions of heavy metals in the soft tissues of a major fouling species Amphibalanus amphitrite living on hard substrate at different sites along the eastern Aegean coast. A. amphitrite has been chosen as a strong candidate for monitoring heavy metals. Sediment and seawater samples were also collected to detect their metal contents in order to gain more information on the environmental conditions and possible bioaccumulation patterns. The physico-chemical characteristics of sampling stations have been measured in order to characterize the sampling area. The order of metal concentrations in barnacles, sediment and seawater decreased in the following order Cu>Fe>Zn>Mn>Cd>Cr>Pb>Hg, Fe>Mn>Zn>Cu>Pb>Cr>Hg>Cd and Fe>Zn>Mn>Cu>Pb>Cr>Cd>Hg, respectively. These results showed that barnacles accumulate Cu in a higher degree than both sediment and seawater. Moreover, metal concentrations in barnacle have the potential for use in any future regulatory framework monitoring and eventually controlling ambient metal pollution levels.

Assessment of organotin (butyltin species) contamination in marine biota from the Eastern Aegean Sea, Turkey.

The marine environment continues to be adversely affected by tributyltin (TBT) release from maritime traffic. Therefore the concentrations of TBT, dibutyltin (DBT) and monobutyltin (MBT) were measured in barnacles, mussels and fish along the Eastern Aegean coastline. The average concentrations of TBT ng Sn g⁻¹ were found to be 235 in fish, 116 in mussels and 635 in barnacles. The highest concentrations of TBT, DBT and MBT were observed in the barnacles which had been sampled in marinas and harbors. All mussels sampled showed values of TBT+DBT, which were below the "tolerable average residue level (TARL)" as currently accepted. This indicates a lack of risk to the consumer. However, 7 out of the 15 fish sampled displayed TBT+DBT levels above the TARL, which indicates that a fish consumer group may be at risk. Barnacles have high potential as biomonitors for the presence of organotin in the Aegean Sea.

Distribution and sources of organochlorinated contaminants in sediments from Izmir Bay (Eastern Aegean Sea).

Eighteen surface sediment samples representative of the entire Izmir Bay were analyzed for organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). This was in order to provide extensive information concerning the recent deposition of these compounds in this area, together with levels, distribution, possible sources and potential biological risk. Sites that were contaminated by high concentrations of organochlorine compounds were associated with dense population, such as the harbour and the Gediz River estuary. Relatively higher ΣDDT concentrations and high DDT/DDE+DDD ratios in the Gediz River estuary indicated DDT usage, probably linked to public health emergencies. According to the established guidelines for sediment quality, the risk of adverse biological effects from such levels of OCPs and PCBs as recorded at most of the study sites was insignificant. But the higher concentrations in Inner bay and in the Gediz River estuary could cause biological damage.

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.