Scientists monitor with phosphorus the algal blooms in European lakes

Aug 28, 2013
Scientists monitor with phosphorus the algal blooms in European lakes
Cyanobacteria bloom in a lake. Credit: CEDEX

An international research team has analysed the relationship between the amount of phosphorus recorded in 1,500 European lakes and reservoirs, and the growth of cyanobacteria, a toxin-producing microorganism. The results show that 23% of these water masses in Spain exceed the level established by the World Health Organisation (WHO). This percentage is closer to 50% for Germany and the Netherlands.

"Toxins produced by cyanobacteria represent a significant health risk both in water used for consumption and for recreation. However, levels of said toxins are not usually measured in , so the WHO has provided risk levels related to the quantity of these in water," Caridad De Hoyos, researcher from the Centre for Studies and Experimentation in Public Works (CEDEX), explained to SINC.

Specifically, the WHO established two cyanobacteria concentrations (2 mm3/l and 10 mm3/l) which should not be surpassed in recreational waters as they could be harmful to human health representing low and moderate probabilities respectively. The potential effects identified range from to allergic reactions and serious .

Now, a study carried out by scientists from the Joint Research Centre (JRC) and other European centres - including CEDEX - reveals that 23% of lakes and reservoirs in Spain exceed the first level established by the WHO, which could lead to cyanobacteria blooms in some of them. The data is published in the Journal of Applied Ecology.

In general, the lakes in central Europe present the most significant health risk. In some countries, over half have exceeded the level 1 - 53% in the Netherlands and 47% in Germany. The situation is better in the Nordic countries such as Norway and Sweden, where this problem affects barely 5% of their water masses.

To obtain this data, the researchers have compared the amount of cyanobacteria with recorded levels of phosphorus in 1,506 European lakes. "The increase of cyanobacteria detected in the last few decades is due to the increase of nutrients in water masses, especially phosphorus," De Hoyos explains.

Phosphorus from agriculture and industry

Scientists have developed a model which gives the maximum potential capacity of water masses to produce cyanobacteria at different phosphorus concentrations reaching lakes and reservoirs from agricultural or industrial activities.

The results show that the probability of exceeding the WHO's level 1 for recreational waters increases from around 5% when there are 16 micrograms per litre (µg/l) of phosphorus present, to over 40% if there are 54 µg/l of the nutrient.

It has also been observed that approximately 50% of lakes studied do not exceed the cyanobacteria levels given by the WHO even though they have high concentrations of phosphorus. According to De Hoyos, "this shows the importance of other factors, such as the water renewal rate, in cyanobacteria growth".

The researcher highlights that the model "can be used to identify nutrient levels which allow us to keep used for recreational purposes, in accordance with required risk levels and the service they provide".

[www.agenciasinc.es/var/ezwebin… balses_image488_.jpg] Cyanobacteria bloom in a lake. / CEDEX

Explore further: Tourists evacuated amid Iceland volcano concerns

More information: Laurence Carvalho, Claire McDonald, Caridad de Hoyos, Ute Mischke, Geoff Phillips, G_abor Borics, Sandra Poikane, Birger Skjelbred, Anne Lyche Solheim, Jeroen Van Wichelen, Ana Cristina Cardoso. "Sustaining recreational quality of European lakes: minimizing the health risks from algal blooms through phosphorus control". Journal of Applied Ecology 50: 315-323, 2013.

add to favorites email to friend print save as pdf

Related Stories

Potent human toxins prevalent in Canada's freshwaters

Aug 14, 2012

Nutrient pollution, one of the greatest threats to our freshwater resources, is responsible for the algal blooms that blanket our lakes and waterways in summer months. Large blooms of cyanobacteria ('blue green algae') can ...

Global warming harms lakes: study

Jul 16, 2012

Global warming also affects lakes. Based on the example of Lake Zurich, researchers from the University of Zurich demonstrate that there is insufficient water turnover in the lake during the winter and harmful ...

Study pinpoints nutrient behind fresh water algae blooms

Aug 22, 2012

University of Alberta ecologist David Schindler has reviewed data from studies of controlling human-caused algae blooms in lakes and says controlling the input of the nutrient phosphorus is the key to fighting the problem.

Novel testing device for detecting toxic blue-green algae

Jun 24, 2013

VTT Technical Research Centre of Finland has developed a fast and affordable testing device for detecting the presence of toxic blue-green algae in water. There is currently no fast, affordable and user-friendly way for consumers ...

Recommended for you

NASA image: Signs of deforestation in Brazil

15 hours ago

Multiple fires are visible in in this image of the Para and Mato Grosso states of Brazil. Many of these were most likely intentionally set in order to deforest the land. Deforestation is the removal of a ...

Sunblock poses potential hazard to sea life

16 hours ago

The sweet and salty aroma of sunscreen and seawater signals a relaxing trip to the shore. But scientists are now reporting that the idyllic beach vacation comes with an environmental hitch. When certain sunblock ...

Is falling recycling rate due to 'green fatigue'?

16 hours ago

It's been suggested that a recent fall in recycling rates is due to green fatigue, caused by the confusing number of recycling bins presented to householders for different materials. Recycling rates woul ...

Study to inform Maryland decision on "fracking"

19 hours ago

The Maryland Department of Environment and Department of Health and Mental Hygiene released on August 18, 2014, a report by the University of Maryland School of Public Health, which assesses the potential ...

User comments : 0