June 28, 2005

Group publishes milk toxin study over US objection

By Maggie Fox, Health and Science Correspondent

WASHINGTON (Reuters) - The National Academy of Sciencespublished a report on Tuesday saying the U.S. milk supply isvulnerable to being poisoned with botulinum toxin, rejectingarguments from the Health and Human Services Department that itmight instruct would-be attackers.

The report, written by Lawrence Wein and Yifan Liu ofCalifornia's Stanford University, outlines one way a smallamount of the paralyzing poison could sicken up to 500,000people. It recommends measures, such as better pasteurizationand careful sampling, to reduce the threat.

The Proceedings of the National Academy of Sciencesoriginally scheduled publication of the paper in late May, butwithdrew its embargoed release to reporters after theU.S.Department of Health and Human Services objected.

It was an unusual move and the academy recommended thatthis be a test case for a debate over whether studies thatcould pertain to biological or chemical warfare be classifiedin the way studies related to nuclear weapons often are.

The academy, an independent body that advises the federalgovernment on scientific and medical matters, met withofficials to discuss concerns.

"Following this meeting, the Council of the NationalAcademy of Sciences decided to publish the article asoriginally accepted, accompanied by this editorial to makeclear our reasons for doing so," Academy President BruceAlberts wrote in a commentary.

All of the information in the analysis was easily availableon the Internet, Alberts argued. He said open publication anddebate can make the nation safer.

"Because science advances through the combination ofknowledge in unexpected ways, the discoveries of eachindividual scientist must be made available to a wide varietyof other scientists, who can then either build upon orcriticize them," he added.

This "scientific free-for all," he said, almost alwaysimproves understanding.


"There is a second advantage to openness. Protectingourselves optimally against terrorist acts will require thatboth national and state governments, as well as the public, becognizant of the real dangers."

The Department of Health and Human Services disagreed.

"Our concern is that if the academy is wrong, theconsequences can be dire," department spokeswoman ChristinaPearson said in a telephone interview.

"Anything that publicizes vulnerabilities in the systemthat could facilitate an attack on the food supply, that is aconcern," she added.

Botulinum toxin, made by bacteria, is the cause of botulismfood poisoning. It is considered a leading potential biologicalweapon, and milk, because it is so widely consumed, isconsidered a vulnerable target.

Wein and Liu set up a hypothetical scenario in which thetoxin was put into milk early in the distribution process.

Because milk is pooled before being packaged anddistributed, this would be an efficient way to try to poisonmany people, they argued.

Other products might be similarly vulnerable -- fruit andvegetable juices, canned foods and some grains.

"In the absence of any detection (i.e., every gallon ofcontaminated milk is consumed), the mean number of people whoconsume contaminated milk is 568,000," Wein and Liu wrote.

"Less than 1 gram of toxin is required to cause 100,000mean casualties (i.e., poisoned individuals), and 10 gramspoison the great majority of the 568,000 consumers."

Quick, on-site testing could foil such an attempt, andslightly better pasteurization would inactivate the toxin, theysaid.

Better security could help, too, they said.