NI Water has confirmed that it does not test drinking water for toxic organisms which have been detected in Ireland for the first time in algae at Lough Neagh.
The presence of the organisms, known as anabaenopeptins, was confirmed in research published last week which found much of the foul-smelling, so-called algal mats on the shore of the lough consist of bacteria primarily associated with livestock and human faeces.
Run-off from agricultural slurry, raw sewage and leaching septic tanks are said to be responsible for the environmental catastrophe that has befallen Ireland’s largest lough.
The research found more than 80% of the bacterial DNA recovered from the algae belonged to potentially hazardous microbes, including E coli, Salmonella and 11 others that cause human illness.
It identified the cause of the bloom as a common species of freshwater cyanobacteria, which under certain conditions produces what its lead author called a “suite of toxins”, known as cyanotoxins.
Dr Neil Reid of the Institute of Global Food Security at Queen’s University Belfast told The Irish News his most pressing concern was people who use the lough coming into direct contact with the toxic algae, which poses an immediate health risk.
He said some of the cyanotoxins exposures at Lough Neagh breach World Health Organisation (WHO) limits.
The biologist said that while NI Water “test for the most common” cyanotoxins, he is concerned that some are carcinogens and that their health impacts would be cumulative rather than immediate.
Lough Neagh provides more than 40% of the region’s drinking water.
The researchers also detected, for the first time in any Irish water body, what Dr Reid refers to as a “whole other class of toxins” called anabaenopeptins, which interact with the cyanotoxins to “produce even greater toxicity than any one by itself” .
He said because the anabaenopeptins had previously not been detected in Ireland, NI Water was unlikely to test for them. The government-owned utility has confirmed that it doesn’t test for the presence of anabaenopeptins, either before or after the water has been treated.
It said its “multibarrier” process would “effectively deal with and remove cyanobacterial cells and algae toxins”.
Dr Reid said: “One can only trust that a multi-filtration system, if effective against cyanotoxins, is likely effective against other compounds but there’s no explicit testing.”
NI Water said the quality and safety of drinking water was its “number one priority” and that its processes ensured the drinking water supplied to customers meets strict drinking water quality standards. It said its tests were in line with the Recast Drinking Water Directive and the WHO guidelines for drinking water quality.
“Where there is a risk for algae to be present in the raw water, the drinking water treatment processes are designed to deal with this risk,” a spokesperson said.
