Industry produces billions of tons of sewage
Concerns have been raised about the environmental impact of expanding the Manx cruise industry.
Canadian researcher Dr Ross Klein addressed a Positive Action Group meeting in Douglas last night, amid government discussions on how to attract more visitng ships into the Island.
His talk centred on the potential returns from a proposed £40 million cruise terminal - but also covered the negative effects ships can have on ocean and air quality.
It's estimated the industry produces a billion tonnes of sewage every year.
But the Manx government insists all liners have a duty to follow international conventions on rubbish dumping and fuel pollution.
Dr Klein says assessing the issue is complex:
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