Inmates sew protective masks at Las Colinas Women's Detention Facility in Santee, California, on April 22, 2020. (SANDY HUFFAKER / AFP)

SAN FRANCISCO — The University of California, San Francisco (UCSF), has unveiled an internal investigation about unethical medical experiments on at least 2,600 incarcerated men in the 1960s and 1970s.

The experiments included putting "pesticides and herbicides" on the men's skin and injecting them into their veins. In one experiment, "small cages with mosquitos" were placed close to the participants' arms or directly on their skin to observe "host attractiveness of humans to mosquitos," the investigation showed.

Two UCSF dermatologists — Howard Maibach and William Epstein — had conducted the experiments at the California Medical Facility

The men were paid for participating, but the investigation raised ethical concerns over how the research was conducted. In many cases there was no record of informed consent.

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"Only one of the remaining 13 publications indicated that informed consent was obtained from its seven human subjects and that the study had been approved by UCSF's Committee for Human Research," the UCSF said in a report.

Two UCSF dermatologists — Howard Maibach and William Epstein — had conducted the experiments at the California Medical Facility, a prison hospital in Vacaville, the report said.

Maibach and Epstein were trained at the University of Pennsylvania by Albert Kligman, a dermatologist who was found to have conducted the unethical research on prisoners, most of whom were Black men, at Holmesburg Prison in Philadelphia from the 1950s to the 1970s, the report said.

Both Kligman and Epstein died, while "Maibach is currently still an active member of the UCSF faculty," the university said.

Arthur Caplan, professor of bioethics at New York University's Grossman School of Medicine, said informed consent is the core protection against involuntary experimentation.

"Consent shows basic respect for dignity and autonomy of the person," Caplan was quoted by The San Francisco Chronicle as saying.

The Nuremberg Code of the late 1940s established that "the voluntary consent of the human subject is absolutely essential," Caplan said.

UCSF Executive Vice Chancellor and Provost Dan Lowenstein apologized in a statement for the university's role in the harm caused to the subjects.

"UCSF apologizes for its explicit role in the harm caused to the subjects, their families and our community by facilitating this research, and acknowledges the institution's implicit role in perpetuating unethical treatment of vulnerable and underserved populations — regardless of the legal or perceptual standards of the time," Lowenstein said.

The public, shocked by the news, expressed their concerns and said the university should do more.

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"An apology isn't enough. Conducting harmful medical experiments on a population of incarcerated, vulnerable men is disgusting. It is inhumane, it is criminal. One of the researchers is still at the university. He should be fired immediately," said Dyjuan Tatro, a resident in New York.

Violating the Nuremberg Code "doesn't need an apology. It needs justice," said Rupa Marya, a doctor of medicine.

"The University of California system, not just UCSF, must thoroughly review its involvement in medical and psychiatric research involving incarcerated people. The same goes for all other universities," said Ray Phillips, a retired college administrator.