Dr. Benjamin G. Ferris Jr. '40, a former professor at the School of Public Health and longtime director of environmental health and safety at Harvard, died Thursday at his home in Weston. He was 77.

Ferris spent his entire professional life at Harvard. He earned his bachelor's degree at the College, received his M.D. from the Medical School and completed his residency at the Harvard-affiliated Children's Hospital.

He joined the School of Public Health as a research fellow in physiology in 1948, was made an associate professor in 1958 and earned tenure in 1971. Ferris served as professor of environmental health and safety until his retirement in 1989.

Ferris also served as director of environmental health and safety for 32 years, from 1957 until his retirement.

Associates said that Ferris separated the department from University Health Services and led its extraordinary--if uneven--growth over the succeeding decades.

"He built the department from the ground up," said Mary J. Corrigan, the current associate director of environmental health and safety. "Our office used to be in Holyoke Center and I think had many homes between there and where the office is now."

As director, Ferris was responsible for the maintenance of environmental health and safety services and for dispensing technical advice to all Harvard students, staff and faculty members.

Among the issues he dealt with were radiation protection, sanitation, industrial hygiene and pest control.

"He was a very wonderful person to work for: very kind, knowledgeable, sincere and dedicated," said Ann Marie Centrella, a member of Ferris' support staff for nearly a decade.

Ferris spent only about 20 percent of his time as director of environmental health and safety. Four days per week, he was teaching and doing research on respiratory disease at the School of Public Health.

Among the highlights of his career was a major prospective epidemiologic study of the health effects of air pollution in six U.S. communities. The study, commonly known as the Six-Cities Study, has been hailed as the premier investigation of the health effects of air pollution.

Ferris was also the first recipient of the Distinguished Achievement Award from the American Thoracic Society.

"We are only beginning to appreciate Ben's contribution to our understanding of respiratory disease, the development of respiratory and environmental epidemiology into mature sciences and the training of a generation of researchers in environmental and occupational health," said Douglas W. Dockery, associate professor of environmental epidemiology. "His passing marks the end of an extraordinary era."

Ferris was also an accomplished mountain climber who served as director of the American Alpine Club. He was part of the first team to climb the second-highest peak in North America, Mt. St. Elias.

Ferris is survived by his wife Stefana, five daughters and nine grandchildren.

Ferris' funeral was held Saturday in Claremont, N.H. A memorial service will be held in First Parish Church in Weston on September 7, according to Dockery.