Food supply chain causes a larger burden on the Baltic Sea than previously thought, as the majority of the nitrogen and phosphate load comes from food production. Consequently, hazardous substances accumulated in the marine ecosystem can pose a risk to the safety of what we eat. Both the burden and the risks caused by hazardous substances can be diminished by selecting the right foods and following dietary guidelines.
Foodweb is a project coordinated by the MTT Agrifood Research Finland that aims to produce information on environmental load of different foods and the environmental risks associated with them, making it easier to select what to eat and what not. The first phase of the project has studied the impacts of food supply chain on the Baltic Sea. A particular emphasis is on the food production and consumption in the Central Baltic Sea region. Participants to the project include the Finnish Environment Institute, the Universities of Latvia and Tartu and the AHHAA Science Centre in Tartu.
Cattle farming is the largest nitrogen producer
The majority of the nitrogen and phosphate load in the Baltic Sea is caused by primary production, while eutrophication is mostly caused by animal feed production that takes up more than half of the arable land area in the Baltic Sea region.
According to Yrjö Virtanen, Senior Research Scientist at the MTT Agrifood Research Finland, meat and milk production are accountable for the major share of the burden.
Their nitrogen load has been found to be larger than previously thought. In life-cycle assessments, the nitrogen load of beef has usually been calculated to be between 30 and 50 grams of nitrogen per one kilo of beef.
– The assessment in this study was based on a model of the entire food supply chain. It shows that the nitrogen load of one kilo of beef is 78 grams, Virtanen concludes.
The nitrogen generated in pork and egg production is about one third, while the amount in poultry production is only one seventh of that in beef production.
The production chains of one kilo of grain or one litre of milk only generate about one fifteenth of the nitrogen load in beef production. For one kilo of potatoes, the nitrogen load is only one hundredth compared to that of beef.
For phosphorus load, the production chain of one kilo of pork generates about one fourth of the phosphorus load from the production chain of one kilo of beef, while for poultry and eggs the share is about one tenth, and for milk it is about one fifteenth compared to beef. These figures vary from country to country according to how efficiently nutrients are used.
Selecting the right foods may help diminish eutrophication
As the financial situation of households has improved, the consumption of meat has also been on the rise. During the last 20 years, the meat consumption in Finland has increased by 20 per cent. The same trend also exists in Estonia and Latvia: compared to the situation 10 years ago, meat consumption in Estonia has increased by 20 per cent, while in Latvia it has doubled.
Researchers believe that every Finn could contribute to bringing down the nutrient load in the Baltic Sea by eating less meat. At the moment, meat consumption, i.e. the share of animal protein of the total energy intake, exceeds dietary guidelines.
– By following the national dietary guidelines we can decrease the load caused by agriculture by about seven per cent, estimates Virpi Vorne, Research Scientist at MTT Agrifood Research Finland.
Fish may be risky
Environmental risks are evident in the Baltic Sea fish, including the Baltic herring. Hazardous concentrations can be made up of PCBs, dioxins, fire protection agents, water-repellent perfluorinated compounds as well as heavy metals, such as mercury and organic tin compounds.
– When eating fish from the Baltic Sea, recommendations should be followed. Fish should be eaten once or twice a week, but there should be variation in the fish species, just to be on the safe side. According to the recommendations of the Finnish Food Safety Authority, people in fertile age, small children and pregnant women should not eat large Baltic herrings, salmon or trout caught from the Baltic Sea more than once or twice a month, says Matti Verta, Chief Scientist from the Finnish Environment Institute.
– But the Baltic Sea is not the only risk source. Hazardous substances gathered from elsewhere in the environment and created when the food is being prepared can also accumulate in what we eat, Verta adds.
Recycled nutrients, transparent risks
Professor Sirpa Kurppa, MTT Agrifood Research Finland, the responsible manager of the Foodweb project, says that every food producer and consumer should now rise up to the task. The nutrient load of the Baltic Sea caused by food production can be decreased significantly by increasing harvests and the ecological efficiency of nutrient use.
– Farming techniques and methods can be improved and the use of fertilisers can be optimised. Nutrients should be recycled efficiently everywhere in society.
Kurppa emphasises the differences in the efficiency of nutrient use in Finland, Estonia and Latvia.
– Consumers should be aware of the most significant challenges in the production chain in their own country. Consumers and the production chain could join forces to significantly reduce the nutrient load in the Baltic Sea.
For more information, please contact:
Sirpa Kurppa, Professor, MTT Agrifood Research Finland,
tel. +358 40 548 6968, [email protected]
Virpi Vorne, Research Scientist, MTT Agrifood Research Finland,
tel. +358 40 487 8522, [email protected]
Yrjö Virtanen, Senior Research Scientist, MTT Agrifood Research Finland, tel. +358 40 763 8441, [email protected]
Matti Verta, Chief Scientist, the Finnish Environment Institute,
tel. +358 40 740 2613, [email protected]