HELCOM publishes reports on hazardous substances and input of nutrients to the Baltic Sea through the region biggest rivers
HELCOM says it has recently published two reports on hazardous substances and inputs of nutrients through the seven biggest rivers in the Baltic Sea region.
The reports show the results from the HELCOM Pollution Load Compilation (PLC) project that carries out pollution load assessment of the Baltic Sea from waterborne, diffuse and natural sources.
"Both reports provide valuable information for assessing progress in reaching the HELCOM Baltic Sea Action Plan (BSAP) reduction targets for hazardous substances and nutrients," said Dmitry Frank-Kamenetsky, the HELCOM Professional Secretary handling matters related to hazardous substances and nutrient inputs.
The first report, Inputs of hazardous substances to the Baltic Sea, presents the findings on heavy metals cadmium, mercury and lead, as well as atmospheric deposition of selected organic pollutants, pharmaceutical residues, and persistent organic pollutants – chemicals that can't biodegrade or take a long time to do so.
According to the report, the inputs of heavy metals and organic pollutants are on the decline overall. On the other hand, pharmaceuticals and persistent organic pollutants are already causing apprehension, despite having been added only recently to the assessment.
First estimates on pharmaceuticals residues released to the Baltic Sea through wastewater treatment could amount to 1800 tonnes per year. Some of these residues have already been detected in various compounds of the Baltic Sea ecosystem.
Nonylphenols, octylphenols and PFOS – persistent organic pollutants which are mainly used for treating metals and textile products, and as flame retardants – were particularly identified as of high concern by the HELCOM countries. Some of these chemicals can disrupt the hormonal balance in living organisms.
The second report published by HELCOM, Input of nutrients by the seven biggest rivers in the Baltic Sea region, highlights the inputs of nitrogen and phosphorous to the sea from the Daugava, Gota, Nemunas, Neva, Oder, Tornio and Vistula.
These rivers cover about half of the Baltic Sea catchment area. 55 million people inhabit this region, leading to high man-made, or anthropogenic, pressure. The nutrient loads are highest in the southern catchments, where population is densest and agricultural activity is intense.
According to a recent HELCOM assessment, the riverine inputs of total nitrogen and total phosphorus contribute about 80 percent and over 90 percent to the total input of these nutrients respectively. The report emphasizes the importance of measures in upstream parts of river basins, including transboundary parts, to reduce nutrient loads and achieve the environmental targets set by the BSAP.
Over-supply of nitrogen and phosphorous remains the lead cause for eutrophication and the growth of algae in the Baltic Sea.
