What are we studying? | Why are we studying? | What are we finding? | What does it mean? | Where can I read more?
What are we studying?
We are studying cobalt and its ability to cause cancer. Cobalt exposure is increasing as cobalt demand rises worldwide due to its use in rechargeable batteries, super-alloys, and magnetic products. Cobalt is classified as a possible human carcinogen meaning there is some evidence it may be a carcinogen, but not enough data to be sure. Cobalt exposure can come from a variety of sources including joint-replacement implants and occupational exposure in industry. We are investigating the lung and the bladder as two key targets of cobalt in order to understand whether cobalt causes cancer in these two organs.
Why are we studying it?
People are increasingly exposed to cobalt including both industrial workers and the general population. A primary route of exposure to cobalt occurs by breathing it in. Currently, there are limited data investigating the ability of cobalt to damage lung cells and cause cancer. To help understand cobalt’s ability to cause lung cancer, we are studying the toxic effects of cobalt in lung cells.
People who have prosthetics such as hip implants may also be exposed to cobalt. Often these implants are made of a mixture of cobalt, chromium and molybdenum. Sometimes, these implants can fail in the body and patients who have them may experience exposure to metal ions and particles released by the implants into their body. Cobalt released from prosthetics in this manner can enter the bloodstream and accumulate in the bladder. Indeed, data show patients with failed hip implants have increased urinary and blood cobalt levels. If cobalt can cause cancer, cobalt that has accumulated in the bladder might damage bladder cells (called urothelial cells) and cause bladder cancer. To help understand cobalt’s ability to cause bladder cancer, we are studying the toxic effects of cobalt in urothelial cells.
What are we finding?
We have investigated both particulate and soluble forms of cobalt in lung and urothelial cells. We have found that both particulate and soluble cobalt cause cell death and damage chromosomes in these cell types, which supports the possibility that cobalt may cause human lung and bladder cancer.
What does it mean?
Our data supports the suggestion that cobalt poses a potential health risk to people who are exposed to it through either inhalation of cobalt or other routes such as systemic release of cobalt from joint implants. Furthermore, because our data indicate that cobalt damages chromosomes, cobalt exposure may contribute to the development of cancer.
Where can I read more?
- Smith, L.J., Holmes, A., Mason, M.D., Zheng, T., and Wise, Sr., J.P. The Cytotoxicity and Genotoxicity of Soluble and Particulate Cobalt in Human Lung Fibroblast Cells. Toxicology and Applied Pharmacology, 278: 259-265, 2014. PMID: 24823294. https://www.ncbi.nlm.nih.gov/pubmed/24823294
- Xie, H., Smith, L.J., Holmes, A.L., Zheng, T., and Wise, Sr., J.P. The Cytotoxicity and Genotoxicity of Soluble and Particulate Cobalt in Human Lung Epithelial Cells. Environmental and Molecular Mutagenesis, 57(4):282-277, 2016. PMID: 27040722. https://www.ncbi.nlm.nih.gov/pubmed/27040722