A survey of more than 250 lakes across Canada has found a potent liver toxin in every province, with the highest concentrations in central Alberta and southern Manitoba.
The survey published in a scientific journal has found the toxin in certain types of blue-green algae found throughout the country.
The toxin, called microcystin, is found in lakes heavily loaded with nutrients from agricultural runoff and development.
The survey found nearly 10 per cent of the 256 lakes surveyed had microcystin levels that exceeded Canadian guidelines even for recreational use.
Study author Diane Orihel said more research is needed to nail down the conditions that produce the toxin.
She says the ideal place for such research would be the Experimental Lakes Area in Ontario.
However, that has been targeted by recent federal government budget cuts.
