Letter: Low pollution risk from supertankers

Sir: By stating that "between 30 and 60 per cent of all supertankers cause a devastating pollution incident during their lives" (Letters, 12 February), Professor Disney and his son have totally misrepresented the data in the reference they quote.

The NAS report gives a rate for serious casualties for the whole tanker fleet and not for major oil spills from "supertankers". The rate of major oil spills is much lower, as is indicated by the very next section of the same report.

Our own database shows that, based on the period since 1974, the actual percentage of "supertankers" suffering a spill of over 10,000 tonnes during their lifetime is, at most, between 2 and 4 per cent. Even this is an over-estimate, since the annual incidence of oil spills has dropped significantly since the 1970s.

CATHERINE GREY

International Tanker Owners Pollution Federation

London EC3