Luxembourg's Ministry of Sustainable Development and Infrastructure has announed that, following the recent detection of algae grouth in the water in the reservoir at Esch-sur-Sure, the samples have been analysed which have identified three species that can produce toxins are potentially harmful to human health.
As a result, current recommendations from the Administration of Water Management (EGM) remain in force, in that swimming in the lake is prohibited, and owners are requested not to let dogs and other pets drink water from the lake, and not to eat fish caught from the lake.
Anyone experiencing health problems after swimming is urged to contact a physician and mention any contact with toxic algae.
Additional analyses will be taken and analysed in the days and weeks ahead which will directly measure the levels of toxins in the lake.
The ministry has emphasised that there is no danger to drinking water from the water reservoir. The purification processes of natural waters by SEBES have proven very effective at the breakdown of toxins.
According to the Grand Ducal regulation of 19 May 2009, the outdoor swimming season ends in Luxembourg on 1 September 2016.
Luxembourg's Institute for Science and Technology (LIST) has stated that the presence of cyanobacteria, also called blue-green algae, shows the importance of having local scientific expertise, by way of their environmental microbiology team. LIST has confirmed that the algae are actually bacteria with a blue pigment that thrives in strong sunshine, little wind, nitrogen supply and abundant phosphorus, etc. These colonial bacteria proliferate and become dominant in the water column, eventually forming efflorescence, or "blooms" on the surface. Apart from the sometimes spectacular visual effect, many species of cyanobacteria produce toxins dangerous to humans and animals, including hepatotoxins (liver damage), neurotoxins (brain) or even dermatotoxins (skin).
LIST researchers are also testing new technologies for preventing the formation of such algae blooms, for example by using locally specific ultrasound waves.
