By Kate Abnett and Simon Jessop
BRUSSELS (Reuters) - The European Union should do more research on the potential harm caused by nuclear power before deciding whether to label it as a sustainable investment, one of the two expert committees tasked with assessing the fuel's green credentials said on Friday.
Brussels is mulling a decision on whether to include nuclear energy in its sustainable finance taxonomy, a list of economic activities that will from next year define which can be labelled as green investments.
The EU's science arm said in March that nuclear power should get a green label.
However, given disagreement among other experts over whether its low CO2 emissions make up for a lack of analysis on the environmental impact of radioactive waste disposal, two expert committees were later tasked with scrutinising its findings.
On Friday, environment experts on the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) said they backed many of the initial report's findings, but were concerned about others.
To be considered green, activities must "do no significant harm" to specific environmental aims, yet SCHEER said the original report had instead considered whether nuclear would "do less harm" than other energy technologies.
"It is the opinion of the SCHEER that the comparative approach is not sufficient to ensure 'no significant harm'," it said in its report, posted on the Commission's website.
The second report, from a group of experts on radiation protection and waste management, was broadly supportive of the original findings.
The Commission said it will now follow up on the findings of both expert reports.
"The inclusion of nuclear in the taxonomy regulation has been subject of intense debate," a spokesperson said in emailed comments.
"While nuclear energy is consistently acknowledged as a low-carbon energy source, opinions differ notably on the potential impact on other environmental objectives, such as the environmental impact of nuclear waste."
EU countries are split over nuclear energy, with some, including France, Hungary and Poland, in favour of the fuel, while others, including Austria, oppose it.
(Editing by Jan Harvey)