Researchers at Hebrew University, working with their colleagues at Fraunhofer Institute for Cell Therapy and Immunology in Germany, have just conducted research showing just how dangerous over the counter acetaminophen, marketed under Tylenol and other brands, can be.

Yet, equally important to the international teams’ findings is the way the researchers arrived at their results.

Instead of relying on traditional animal testing, the innovative scientists conducted the study using a tiny ‘organ-on-a-chip’ that allows researchers to assess effects on liver cells without using animal test subjects.

According to Prof. Yaakov Nahmias, the director of the Alexander Grass Center for Bioengineering at the Hebrew University and the lead author on the project, the ‘organ-on-a-chip’ merges both electronics and biological materials in an innovative way.

“The liver organs we created were less than a millimeter in diameter and survive for more than a month,” said “We realized that because we are building the organs ourselves, we are not limited to biology, and could introduce electronic and optical sensors to the tissue itself. Essentially we are building bionic organs on a chip.”

The bio-chip is a billion dollar idea, according to Yissum, the technology transfer corporation of Hebrew University, and is already yielding breakthrough results.

In their latest trial using the chip, for example, they have already discovered acetaminophen, even when taking at “safe” doses can harm the liver and damage cells.

One expert in acetaminophen who was not directly involved in the study said that the findings and further warnings about acetaminophen’s toxicity are important to better understanding the popular drug.

“We knew that acetaminophen can cause nephrotoxicity as well as rare but serious skin reactions, but up until now, we didn’t really understand the mechanism of such effects,” Prof. Oren Shibolet, head of the Liver Unit at the Tel Aviv-Sourasky Medical Center said, adding the group’s findings better explain some of the drug’s side effects.

He also added he was hoping the new ‘organ-in-a-chip’ technology will ultimate “transform” in drug research and safety while reducing the need for live animal tests.

“This new technology [the organ-in-a-chip] provides exceptional insight into drug toxicity, and could in fact transform current practice,” Shibolet said.