Chemical threats to the Baltic Ecoregion

Baltic Sea is one of the world's most polluted seas

The cocktail of hazardous substances in the Baltic Sea includes persistent and bio-accumulative substances such as PCBs, DDT and lindane as well as endocrine-disrupting substances such as TBT (tributyltin) and dioxin.

Such substances are of very high concern since effects may occur with a long delay in time, including future generations. Persistent chemicals can travel a long distance via the atmosphere or water currents and accumulate in biota, including humans, far away from the source of pollution.

Substances that interfere with the endocrine system can cause effects at very low concentrations and a safe dose is often unpredictable. Numerous wildlife species, including mammals, birds, fish, reptiles, and mollusc have been already affected.

In the Baltic region, hazardous substances are emitted from all stages of the industrial product chain – from the raw material handling, transport and the production processes, to the use of products and the handling of these as waste. The major pathway into the marine environment is wastewater (industrial and urban), air, agricultural run-off and direct emissions from ship transport, harbour operations and offshore installations.

Environmental impacts
Due to international endeavours in environmental protection, the concentration of well-known contaminants such as mercury, lead, PCBs, dioxins, DDT, lindane and other organochlorine components in sea-water and biota has decreased during the last 20 to 30 years.

The improvement of the breeding success of marine birds (white-tailed sea eagle and guillemot) and the recovery of populations of the three seal species are thought to be related to the diminishing levels of organic contaminants. However, there are still serious concerns with regard to the level of contamination and evidence of toxic effects in biota.

• Many female seals are still unable to produce pups due to uterine occlusion related to PCBs and dioxins in the environment. The concentration of these contaminants seems to have remained stable during the 1990s, indicating that some relevant, possibly regional, inputs still exist. As a consequence the Swedish Food Administration recommended in 1995 that women of childbearing age should limit their consumption of Baltic Herring and Salmon.
• Another emerging problem is chronic intestinal ulcers, which are affecting an increasing number of young grey seals. These are probably caused by contaminants disrupting the seals immune system. The precise mechanisms, however, remain unknown
  

Overall goal
WWF's Baltic Ecoregion Programme supports the adoption of a new European chemical policy and works to halt the release of the most dangerous hazardous substances into the Baltic Sea within one generation.

Related Links

• Stockholm Convention on persistent organic pollutants (POPs) 
• Our work to reduce the threat of toxics chemicals