The plaintiff, Daniel Stephenson was a helicopter pilot in Vietnam from 1965 to 1970 and diagnosed with bone marrow cancer in 1998. He said his illness was due to contact with the herbicide.

Stephenson can now sue major chemical manufacturers such as Dow Chemical and Monsanto, the main producers of the substance, after the Supreme Court, split four-four and with one abstention, failed to reach consensus.

The plaintiff can go ahead and sue the herbicide manufacturers despite a 1984 out of court collective settlement since the court found Stephenson had inadequate representation at the time of the settlement.

However, the Supreme Court said it needed more time in the case of Joe Isaacson, who spent a year in Vietnam at a base from which planes and helicopters used to spread Agent Orange operated. Isaacson has been diagnosed with Hodgkins disease, a form of lymph cancer.

Between 1961 and 1971, the US and South Vietnamese armies used millions of litres of herbicides containing toxic dioxins to destroy jungle and crops and deny their communist enemies food and cover.

The dioxins ended up in the food chain and are today blamed for widespread health problems such as congenital malformation, cancer and paralysis.

Vietnam says as many as one million people have been affected by Agent Orange.

WAR.WIRE