N APRIL 15, 1970, Dr. Jesse L. Steinfeld, the Surgeon

General of the United States, appeared before a hearing

of the Senate Subcommittee on Energy, Natural Resources,

and the Environment, headed by Senator Philip A. Hart,

which was investigating the potential hazard to human

health of the widely used phenoxy herbicide 2,4,5-T. He

announced a series of governmental actions aimed at limit-

ing the use of 2,4,5-trichlorophenoxyacetic acid around

homes, on farms, and on other areas in the United States.

On the same day, the Deputy Secretary of Defense,

David Packard, announced that the American armed forces,

which had been using 2,4,5-T in the Vietnam war, would

stop using it. The employment of the compound in aerial

defoliation operations over huge tracts of South Vietnam

for the stated purpose of denying cover to vietcong forces

but also for the unstated purpose of creating a flow of

refugees from villages controlled by the Communists into

areas controlled by the South Vietnamese government

had aroused increasing protests from biologists in this

country, who maintained that the 2,4,5-T had a potential

for causing birth defects among the offspring of Vietnamese

women exposed to it. Indeed, studies made for our govern-

ment from 1966 onward by an organization known as

Bionetics Research Laboratories, of Bethesda, Maryland,

had shown that the herbicide caused a significant number

of deformities in the unborn offspring of female mice and

rats.