Distribution of Halogenated Organic Material in Sediments from Anthropogenic and Natural Sources in the Gulf of Finland Catchment Area

The paper gives an overview of Estonian experiences with hazardous substances monitoring, as well as some recent results on this kind of monitoring in the aquatic environment, biota and sediments of the heavily industrialized North Estonia. Owing to its specific local conditions, the present list of priority hazardous substances of Estonia includes 1-and 2-basic phenols, heavy metals (Cr, Cu, Ni, Zn) and persistent organic pollutants (HCH, HCB, PCB, DDT, PCDD, PCDF, DL-PCB). The concentrations of hazardous substances in the sea and surface waters are currently low, but elevated concentrations may appear in bottom sediments of river estuaries and in fat tissues of fish. During recent decades the state of the North Estonian environment regarding the hazardous substances has continuously improved due to a decreased pollution load, ban of certain compounds, self-purification processes and sinks.

Section: The Main Pollution Sourcesmentioning

confidence: 99%

Hazardous substances in the water, biota and sediments of the North Estonian coastal sea

Roots

Suursaar

2010

Section: Pulp and Paper Industrymentioning

confidence: 99%

North-East Estonian coastal sea: recovery from the past anthropogenic pressure and new stressors on the background of natural variability

Suursaar

Aps

Kotta

et al. 2009

The heavily industrialized NE part of Estonia has been an environmental hot spot for decades. The oil shale industry, thermal power plants, a cement factory and a Soviet-era depository of radioactive wastes have seriously impacted virtually every component of the environment. This study focuses on environmental changes in the coastal sea, which comprises the southern part of the Gulf of Finland. It is based on national marine monitoring data (since 1968), as well as on recent in situ measurements on hydrodynamics, pollution spread, and on bottom habitat recovery. Starting from the 1990s, improvement of the water quality in the Gulf of Finland is evident. After re-orientation into market economy, substantial economic recession took place in Estonia in the 1990s. The pollution load from both industrial sources and from Narva River decreased. On the other hand, new water protection directives were introduced. However, together with economic growth in the 2000s, some new threats arose, e.g. in relation with the construction of ports at Kunda, Muuga, Sillamäe, and a new pulp mill at Kunda. The replacement of oil shale-based energetics with a nuclear power plant is currently under discussion.

“…Until 1989, untreated waste from the Tallinn mill was discharged to the southern part of the Tallinn Bay, which was the most polluted zone along the Estonian coastline in those days [1]. The Bay featured very low pH, low oxygen and high N-NH 4 content. The quality of the water also failed markedly by organoleptic standards.…”

Section: Introductionmentioning

confidence: 99%

“…Today, most pulp mills utilize a chlorine-free bleaching process. However, about 50% of the total organochlorine inputs from pulp mills since the early 1940s still reside in the Baltic Sea -mainly in the bottom sediments [4].…”

Section: Introductionmentioning

confidence: 99%

Monitoring of pulp mill effluents in the coastal waters of North Estonia

Suursaar¹,

Aps²,

Martin³

et al. 2008

In September 2006, AS Estonian Cell, a brand new aspen pulp mill was opened near Kunda. Partly due to ill memories of past environmental problems in the region, the environmental standards for the plant were set very high. The factory features sulphur free production, chlorine free bleaching and low fresh water consumption. High requirements were put on environmental monitoring. The purified wastewater is conducted via a pipe into the Baltic Sea at a depth of 10 m, about 1.5 km from the coast, and monitoring of the fate and possible effects of the effluents was launched. The monitoring programme includes repeated water and biota samplings and a study of the hydrodynamic regime. It appeared that due to good dilution conditions, the impact of the factory on the abiotic environmental components is barely visible in the background of normal seasonal and storm-generated variability. There may be small changes in bottom organisms in the vicinity of the outlet, though. The preliminary results basically confirm that the impact of the pulp mill on the coastal sea is not large and the environmental risks are generally well handled.