By LISA FELSTON, Associated PressWASHINGTON (AP) A mysterious new chemical pollutant may cause cancer in laboratory animals, raising new questions about the role of CO2 in climate change.
The chemical, COX-2, is a powerful greenhouse gas, but its effects on animal health have not been fully explored, and there’s no way to know how long it lingers in the environment, scientists say.
Scientists have long debated whether humans are causing CO2 to accumulate in the atmosphere.
But this is the first time they have found evidence that the pollutant is causing tumors.COX-1 is an enzyme that converts carbon dioxide to oxygen.
COX2, on the other hand, can form on surfaces, causing the growth of tumors.
So scientists had thought that COX enzymes might work together to produce tumors.
Scientists were surprised to find that the enzyme produced tumors on a small percentage of animals that were exposed to COX inhibitors, but that effect disappeared on animals exposed to a mixture of COX1 and COX 2 inhibitors.
The result, the study authors said, is that there might be a synergistic effect between the COX inhibitor and the CO2-depleting enzyme.
The study was published Wednesday in the journal Nature Climate Change.
It is the latest in a series of scientific papers that have looked at the effect of COex inhibitors on cancer.
The new study is one of several papers that are raising questions about COex.
Its authors say it suggests that COex may be contributing to the growth and proliferation of cancer cells.
The research also adds to a growing body of research that suggests that cancer cells are capable of adapting to COex in a way that increases their ability to survive and reproduce.
COex has been linked to a variety of cancers, including breast, prostate and colon cancers.
Researchers are also trying to figure out how COex might be causing other kinds of tumors, including tumors in the lungs.
In the study, researchers found that COEX-2 did not increase tumor growth on a subset of laboratory mice that were genetically altered.
The researchers said the result was a result of differences in the gene coding for the enzyme and not an increased mutation rate.
In addition to raising new scientific questions about why COex is causing cancer, the finding is also raising more questions about how COEx works.
COEx is a member of the enzyme group of enzymes called COX3, and it can alter how much CO2 is converted to oxygen, the researchers wrote.
It was unclear whether the enzyme could have been involved in the effects of COEx on cancer cells or whether it might simply be a byproduct of its function.
The researchers also did not test COEx for its effects in humans.
COEX was initially thought to be a benign enzyme, but it is not.
And because COex’s effects are not known, researchers are not sure if its effects are beneficial or harmful.
It is unknown how long COex can remain in the body.
Scientists are working on a technique that could remove COex from the environment without harming human health, the authors said.
Scientists at the University of Colorado at Boulder and the University in Washington, D.C., used the enzyme to study mice that are genetically engineered to produce COX, which can be produced by dividing mice in a laboratory.
They used the genetic alterations to produce mice with tumors.
When the researchers switched to COEX inhibitors, the mice grew tumors at rates that were far lower than controls, the investigators said.
The mice showed signs of increased cancer and a decrease in fertility, including decreased eggs and a decreased number of sperm cells, the team wrote.
The scientists said the results suggest that the tumors were more likely to grow in the COex-inhibitor-treated animals, but they did not say why the tumors grew.
The authors did not explain how the tumors might be more likely in the control animals.
They also did no testing COex for its effect on human health.
The University of Washington in Seattle said it has found no evidence that COx inhibitors could cause cancer.
However, it said in a statement that the new study “addresses a number of questions about whether COex1 and 2 are interacting and could be involved in tumorigenesis.”
The new paper, “A complex relationship between COex and cancer,” was published online Aug. 25 in the Journal of Biological Chemistry.
It was co-authored by Daniel B. Smith, a scientist at the U.S. Department of Energy’s Pacific Northwest National Laboratory.