The once pristine Baltic Sea waters have become strongly eutrophicated, i.e. saturated with nutrient components. That is a serious problem threatening the sea’s ecosystem as well as the Baltic Sea coastal inhabitants.

The major nutrients that stimulate eutrophication are phosphorus and nitrogen. The amount of natural phosphorus and nitrogen in the Baltic Sea has increased dramatically due to modern human economic activities. Presently the sea contains four times the amount of nitrogen and eight times the amount of phosphorus it had in 1900, and coastal waters are in bloom thirty to forty times more often than they were at the beginning of the twentieth century.

As nutrients, various forms of phosphoric and nitrogenous aggregates stimulate the photosynthesis process, which in turn produces biomass. Yet when water is enriched with too large an amount of nutrients, algae and other plants grow in excess, leading to a disruption of balance of living resources. This phenomenon is called eutrophication.

In water bodies, eutrophication degrades the clarity of water, while the suspended biomass of phytoplankton is a wonderful substratum for the proliferation of bacteria; some algal blooms can even release toxic chemicals. Other processes follow later: the putrification of biomass and the formation of sulphuretted hydrogen and other water-polluting materials. As a result, fish and other water organisms suffocate on a massive scale, and there is a risk that people might contract various diseases.

Around eighty percent of the nutrients are delivered to the Baltic Sea by rivers or directly from the surrounding territories. The major sources of nutrients are high-yield agriculture and urban runoff.

Although the inflow of nutrients to the Baltic Sea has dwindled over the last year a little, the symptoms of eutrophication did not diminish.

The governments of the Baltic countries have acknowledged that eutrophication is of the main problems facing the Baltic Sea and have pledged to reduce the nutrient pollution. One of the major goals of the action plan regarding the Baltic Sea—which was prepared by the Helsinki Commission, or HELCOM, and approved by the Ministers of Environment Ministries in the Baltic countries—is to reduce phosphate and nitrogen inputs into the Baltic Sea by forty-two and eighteen percent, respectively, yet the taken measures have appeared too weak for achieving the set goals or their implementation is facing difficulties.

Agriculture

About forty percent of phosphorus and sixty percent of nitrogen are deposited into the Baltic Sea waters by means of agricultural activities. Nitrogen and phosphorus appear in the composition of mineral fertilizers and animal dung. As early as 1950, Western Europe increased the use of nitrogen and phosphorus in its agricultural practices, and in 1980 these nutrient aggregates were used in immense quantities. When the dung or mineral fertilizers are accumulated, transported, or used to fertilize fields, a large proportion of them remains in the environment. In the form of nitrate and ammonia compounds, nitrogen aggregates dissolve in water very easily and are delivered to rivers by underwaters. Phosphates are not deposited into the deeper layers, as they are washed away by rainwater from the surface of fields, especially during heavy rain seasons or the melting of snow. Earlier or later, these aggregates are deposited into the Baltic Sea. Therefore, it is crucial that the Baltic Sea coastal countries engage in environmentally friendly farming if they want to reduce the level of eutrophication in the Baltic Sea.

Phosphates in Urban Runoff

Phosphate compounds are delivered to water bodies with the discharge of chemicals (that include phosphate compounds) from households, industries, utilities sectors, and other spheres of modern life. The use of these chemicals is growing rapidly. Most often, those are various washing and cleaning detergents.

In particular, a large amount of phosphates, in the form of sodium tripolyphosphates, are found in laundry detergents that are used to soften water and improve the effectiveness of washing. Phosphorus increases the effectiveness of the washing process as it binds hardness-inducing salts (by making them soluble) and removes deposits or prevents their formation. The carrier of the other components of the laundry detergent works in a similar way.

We can also find phosphates, in the form of orthophosphate acids, in the composition of chemicals designated for cleaning, processing of metals against corrosion, and other materials.

According to the data collected by the Helsinki Commission HELCOM, the level of eutrophication in the Baltic Sea would decrease by twenty-four percent if the above compounds were not used in washing detergents. Having understood the damage that was being done by these detergents, some manufacturers began introducing a phosphate-free technology. If phosphate-free detergents enter the market and replace phosphate-rich detergents, in a few years we will see some positive results in the Baltic Sea.

Moreover, phosphates can be easily removed by setting up efficient cleaning technologies for water runoff. We could reduce the level of discharged nutrients if we improved the cleaning of water runoff and began using phosphate-free detergents. The application of both measures, not just one, would be much more beneficial to the sea environment.