Comprehensive environmental monitoring and assessment of protected wetland and lake water quality in Croatia and Serbia.

The irresponsible and uncontrolled use of water bodies for long period of time leads to pollution and water quality degradation, particularly in sensitive protected terrestrial and aquatic areas as lakes and wetlands situated in the vicinity of human habitations. Vulnerable ecosystems, the Lake Zobnatica, Serbia and the Wetlands of Tompojevci, Croatia, are characterized as protected natural areas and are surrounded by agricultural land and developed anthropogenic activities. In the samples of surface, ground water and agricultural runoff the key physicochemical parameters were determined. The results of analysed water characterized the Lake water quality class as IV-V. The measured parameters for the Lake show the high values of nutrients, particularly in ground water and agricultural runoff, pH value higher than 8.5 and lower values of dissolved oxygen (DO) than 5 mg/L in the most of the examined water samples. According to the results and maximal allowable values Wetlands belong to the class V water quality, with high trophic state and poor eco-status according to Croatian and Serbian national Laws and By-Laws. The pH value higher than 8.5 of ground water in Wetlands of Tompojevci signifies alkaline groundwater. The maximum concentrations of orthophosphates in ground water and agricultural runoff (10.875 and 10.886 mg/L, respectively) imply the high level of agricultural pollution. Research study of water samples has been performed from 2017 to 2019 within the Interreg IPA CBC Croatia-Serbia Project AF_HR-RS135_SeNs_Wetlands. This type of parallel and comparative research in Serbia and Croatia was conducted for the first time.

Comparison of spectrolyser device measurements with standard analysis of wastewater samples in Novi Sad, Serbia.

On-line monitoring was performed using spectrolyser equipment, coupled with laboratory analysis for samples collected from wastewater discharge in the city of Novi Sad, Serbia, during first 24 h of three and 48 h of six monitoring campaigns from December of 2012 to April of 2013. Significant correlation with R(2) > 0.9 was observed between laboratory analysis and spectrolyser measurements for chemical oxygen demand (COD) and biological oxygen demand (BOD) concentrations. COD/BOD5 ratio in combined industrial and municipal wastewater ranged from 1.2 to 2.0 indicating the presence of biodegradable organic matter which could be easily removed using aeration treatment process. Micro/trace element and/or heavy metals in wastewater samples were within the limits as per the standard prescribed for wastewater, and should not pose any serious hazard risk. However BOD, COD, ammonia and total phosphorus concentrations were measured above the limit value according to Serbian and EU legislation and should be reduced before discharging wastewater directly into the Danube River.

Human milk POPs and neonatal risk trend from 1982 to 2009 in the same geographic region in Serbia.

Three groups of POPs - DDT, HCH and PCBs were monitored in early human milk for 27 years (1982-2009), as a measure of environmental pollution in the same geographic region (South Backa, Voyvodina, Serbia). Measurements were performed using ECD GC Varian 3400. Concetrations of DDT and HCH had general decreasing trend from 1982 to 2009. However, the concentrations of both groups of compounds showed small rises in 1994. Concentrations of PCBs had general decreasing trend from 1982 to 2009 - smooth and steep only till 1994 and with two small peaks in 2003 and 2009. The latest estimated daily intake of DDT and HCH was well below the EU upper limit for pesticides in food intended for infants and small children. Although the estimated daily intake of PCBs was far below the upper limit for daily milk products in Serbia, its increase in 2003 and 2009 is a clear indication of environmental influx of these compounds after the 1994 measurements. The likely explanation for such POP profiles in South Backa could have been a series of negative environmental impacts escalating in 1999, after which four hot spots were identified in Serbia (Novi Sad, Pancevo, Bor and Kragujevac) by UNEP. The results of this monitoring showed that although a long standing environmental presence of POPs has a decreasing trend, their occasional output in the environment may cause bioaccumulation and biomagnification in human organisms which already start in the neonatal age through mother-child transfer via human milk.