Scientists have found clear evidence that whales are absorbing high
levels of toxic heavy metals, with cadmium found in the brains of pilot
whales which washed up in Scotland.
The research shows for the first time that cadmium – known to pass into
the brains of infant and unborn whales - had also passed across the
so-called blood-brain barrier in adult whales.
They said their findings also suggested that mercury concentrations could be increasing high enough in the seas “to lead to additional toxic stress in the long-lived marine mammals”, with higher concentrations increasing with age.
In three of the whales aged nine years or
older, the mercury concentrations were higher than the toxic levels
which would cause severe neurological damage in humans.
Mercury in some of the beached whales brains was at levels high enough
to cause severe neurological damage in humans, say scientists.
Photograph: Andrew Milligan/PA