17 May 2013

from Dr.DK Website

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Researchers from the United Kingdom, the Netherlands and Sweden

have shown great interest in the five girls’ biology experiment.




Take 400 cress seeds and divide them into 12 trays.


Then place the trays in two rooms at the same temperature, six in each room. Give the trays the same amount of water and sunlight over 12 days, but expose six of the trays to mobile phone radiation.

This is the recipe for a biology experiment so ingenious that it has attracted international attention from leading biologists and radiation experts.


The experiment is the brainchild of five girls from class 9.b at Hjallerup School in North Jutland, and it all started when the girls were finding it difficult to concentrate in their lessons.

“We all thought we experienced concentration problems in school if we slept with our mobile phones at the bedside, and sometimes we also found it difficult sleeping,” explained Lea Nielsen, one of the five budding researchers.


The experiment


The school did not have the equipment to test the effect of mobile phone radiation on the girls themselves, which, as it turned out, was probably a good thing.


Consequently, the girls had to find an alternative, and the solution they came up with was cress seeds.

Six trays of seeds were placed in a room with no radiation, while six were placed in another room alongside two routers emitting roughly the same type of radiation as an ordinary mobile phone.



The “healthy” cress,

which was not exposed to radiation from the routers.

Then the girls just had to wait 12 days, observe, measure, weigh and take photos.


The results spoke for themselves: the cress seeds alongside the routers did not grow at all, and some even mutated or died.

“It’s really frightening that there was such a big effect, and we were really struck by the results,” said Nielsen.


The “sick” cress,

which was exposed to radiation from the routers.



The reactions


The experiment secured the girls a place in the final of the “Young Researchers” competition, but that was only the beginning.


So far, leading researchers from the United Kingdom, the Netherlands and Sweden have shown great interest in the girls’ project.



Foto: Kim Horsevad

From the left: Lea Nielsen, Mathilde Nielsen,

Signe Nielsen, Sisse Coltau and Rikke Holm.

Professor Olle Johanson of Karolinska Institutet in Stockholm is among those to have been impressed.


Johanson considers the experiment to be ingenious and now wants to repeat it with a Belgian research colleague, Professor Marie-Claire Cammaert of the Université libre de Bruxelles.

“Within the limitations of their understanding and ability, the girls have carried out and documented a very elegant piece of work. The wealth of detail and precision is exemplary, the choice of the right cress is very intelligent, and I could go on,” said Johanson.

Johanson also wasted no time in issuing an invitation:

“I really hope they spend their future working lives in research because I definitely think they have a natural aptitude for it. Personally, I would love to have them in my team!”



No more bedside mobiles


The five girls from North Jutland have not yet made any decisions about their future careers.


They are still taken aback by all the sudden attention.

“This has given me a constant buzz. I still can’t quite take it all in,” said Nielsen.

There has also been another rather more down-to-earth consequence of the cress seed experiment.

“None of us sleep with our mobile phones at our bedside any more. Either we keep them at a distance or in another room. And we always turn off the computer,” she said.