Distribution and environmental risk evaluation of heavy metal in core sediments from Lake Çildir (NE Turkey).

This study examined the vertical distribution of heavy metals in core sediments taken from Lake Çildir, Turkey, and their potential ecological risks together with organic carbon content and chlorophyll degradation products. Samples were collected from six sampling stations determined along two main transections aligned in north-south and east-west directions. The enrichment (EF) and contamination factor (CF), potential ecological risk (PER) index, and pollution load index (PLI) were calculated from the obtained results. For the elements Pb, As, and Cd, a moderate level of contamination was detected, whereas a moderate-to-high concentration level was obtained for Mn. The highest contamination level was found for Hg. A pollutant accumulation exists particularly in the surface sediments. Cd and Hg are the only two metals considered to be a potential risk factor in the lake.

Temporal Changes in Concentrations of Some Trace Elements in Muscle Tissue of Crayfish, Astacus leptodactylus (Eschscholtz, 1823), from Keban Dam Lake.

Crayfish (Astacus leptodactylus Eschscholtz, 1823) is the native crayfish species in Turkey. It was exported regularly to Western Europe. In this study, bioaccumulation and temporal trends of some trace elements (arsenic: As, cadmium: Cd, copper: Cu, mercury: Hg, lead: Pb, and zinc: Zn) in edible abdomen muscle of crayfish from Keban Dam Lake (Elazig, Turkey) were investigated for the 2006-2012 period. Sequence of metal concentration levels was Zn > Cu > Hg > Pb > Cd > As in muscle tissues. The highest concentration of Zn (21.69 mg kg(-1)) was detected in 2006, while the lowest (4.35 mg kg(-1)) in 2009. In general, it was found that the concentrations of trace elements investigated were lower than the maximum permissible limits of the food regulations of the Ministry of Food, Agriculture, and Livestock (MFAL), the Turkish Food Codex and Commission Regulation (EC). If the crayfish selected for the study are recognized as bioindicators of environmental pollution, then it is possible to conclude that the changes in studied trace elements concentrations in the Keban Dam Lake are being steady.

Ecological risk assessment of heavy metals in surface sediments of northern littoral zone of Lake Çildir, Ardahan, Turkey.

In this paper, the heavy metal levels (Cu, Pb, Zn, Ni, Mn, Fe, As, Cd, Cr, Hg), organic carbon, and chlorophyll degradation products were studied to prove their ecological effects in Lake Çildir, where fossil fuels are used as an energy source in the studied area for most of the year, and domestic waste from settlements is discharged directly into the lake. Sediment samples were collected from six sites on the northern shore of Çildir Lake, Turkey in November 2012. Enrichment (EF) and contamination factor (CF) values were determined, and Pollution Load (PLI) and Potential Ecological Risk (PER) indices were calculated. Average concentrations of heavy metals in the sediments were, in descending order, Fe > Mn > Zn > Ni > Cr > Cu > Pb > As > Cd > Hg, respectively. According to mean values, the source of these elements may be considered natural due to lack of enrichment in Cu, Pb, Zn, Ni, and Cr in the sediment samples. Regarding enrichment of As, Cd, Mn, and Hg, the highest EF belongs to Hg. PLI and PER values indicate there are moderate ecological risk in the lake.

Determination of bioaccumulation of heavy metals and selenium in tissues of brown trout Salmo trutta macrostigma (Duméril, 1858) from Munzur Stream, Tunceli, Turkey.

The objective of the present work was to determine the bioaccumulation of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), uranium (U) and selenium (Se) in gill, liver, and muscle tissues of the fresh water fish Salmo trutta macrostigma (Duméril, 1858) in Munzur Stream, Tunceli, Turkey. The highest concentrations of U (1.83 µg kg(-1)), Pb (119.84 µg kg(-1)) and Se (1.31 µg kg(-1)) were recorded in the gills of S. t. macrostigma. Concentrations of As (46.27 µg kg(-1)), Cd (109.19 µg kg(-1)), Hg (16.40 µg kg(-1)), Cu (18.19 µg kg(-1)) were recorded at highest levels in the liver. The results showed that there were significant differences in concentrations of As, Cd, Cu, Pb, Se, U and Hg in gill, liver and muscle tissue (p < 0.05). Heavy metals were within the edible parts of the investigated fish were in the permissible safety levels for human uses.

Rubella immune status of pregnant and non-pregnant women in Istanbul, Turkey.

OBJECTIVE: Rubella immunization rates are not optimal and infections during pregnancy still occur since many countries incorporate no rubella vaccine in their national immunization program. The evaluation of immunity to rubella virus relies on the presence of specific antibodies. This study was undertaken to determine in a cross-sectional survey whether rubella virus circulation in the Istanbul city, induces detectable immunoglobulin G (IgG) antibodies with a protective level, in a random group of pregnant and non-pregnant women. METHODS: One hundred and sixty women of 20-41-years of age (average 24-years) were grouped as follows: 1. Forty-eight married women. Among these were 41 pregnant women (33 delivered normally, 8 aborted). 2. One hundred and twelve single women. Samples were collected during the periods from October 2000 through to March 2001 and from November 2001 through to May 2002. Rubella specific IgG antibodies were detected (by the ELISA test) in all women tested. RESULTS: Quantitative analysis of the IgG levels showed noticeable variability that ranged between 24-143 IU/ml (average 94). One hundred and forty-five (91%) out of 160 women had rubella IgG levels of above 50 IU/ml with a range of 54-143 IU/ml (average 92) while 15 (9%) had a level between 24-46 IU/ml (average 38). Rubella IgG-avidity test revealed that 116 (73%) of women had high IgG avidity, 22 (14%) had intermediate avidity and 20 (13%) showed low avidity. Two women who were IgM positive, each had either high or intermediate IgG avidity. CONCLUSION: All women tested were seropositive for rubella specific IgG antibodies suggestive of natural virus circulation within the community. Although the majority appeared to possess protective level of such antibodies, screening for protective immunity appears always to be a necessity for future protection against reinfection.