Tungsten accumulation in bone raises health concerns

McGill University scientists have identified exposure to tungsten as problematic after they determined how and where high levels of the metal accumulate and remain in bone.

“Our research provides further evidence against the long-standing perception that tungsten is inert and non-toxic,” said Cassidy VanderSchee, a PhD student and a member of a McGill research group headed by chemistry professor Scott Bohle.

Tungsten is a hard metal with a high melting point and, when combined with other metals and used as an alloy, it’s also very flexible.

Because of these properties and under the assumption that tungsten is non-toxic, it has been tested for use in medical implants, including arterial stents and hip replacements, in radiation shields to protect tissue during radiation therapy, and in some drugs. Tungsten is found in ammunition as well as in tools used for machining and cutting other metals.

Tungsten also occurs naturally in groundwater where deposits of the mineral are found. Exposure to high levels of tungsten in drinking water in Fallon, Nevada, was investigated for a possible link with childhood leukemia in the early 2000s. This investigation lead scientists to question the long-held belief that exposure to tungsten is safe and prompted the Centers for Disease Control and Prevention in the U.S. to nominate tungsten for toxicology and carcinogenesis studies.

>Read more on the Canadian Light Source website

Image: Cassidy VenderSchee

Success in clinical trials driving a shift in the treatment of blood cancers

The Australian Synchrotron is proud to be growing Australia’s capacity for innovative drug development, facilitating the advance of world-class disease and drug research through to local drug trials. Recent success in clinical trials of Venetoclax, the chronic lymphocytic leukaemia (CLL) drug developed by researchers from the Walter and Eliza Hall Institute and two international pharmaceutical companies is driving a major shift in the treatment of a range of blood cancers, according to a media information from the Peter MacCallum Cancer Centre.

>Read more on the Australian Synchrotron website

 

Gold protein clusters could be used as environmental and health detectors

Peng Zhang and his collaborators study remarkable, tiny self-assembling clusters of gold and protein that glow a bold red. And they’re useful: protein-gold nanoclusters could be used to detect harmful metals in water or to identify cancer cells in the body.
“These structures are very exciting but are very, very hard to study. We tried many different tools, but none worked,” says Zhang, a Dalhousie University professor.

Peng Zhang and his collaborators study remarkable, tiny self-assembling clusters of gold and protein that glow a bold red. And they’re useful: protein-gold nanoclusters could be used to detect harmful metals in water or to identify cancer cells in the body.

“These structures are very exciting but are very, very hard to study. We tried many different tools, but none worked,” says Zhang, a Dalhousie University professor.

>Read more on the Canadian Light Source website

Image: The protein-gold structure. The protein, which both builds and holds in place the gold cluster, is shown in grey.

Investigation of metal deposition in organs after joint replacement

Synchrotron analysis shows potentially harmful metals from implants can find their way into human organs.

The hip replacement is considered to be one of the most successful orthopaedic interventions, with 75,000 performed each year by the NHS alone. However, the implants used to replace hips contain metals, such as chromium and cobalt, which are potentially toxic and which can be deposited into tissues around the implant site due to wear and corrosion. A team of researchers used X-ray absorption spectroscopy (XAS) on the I18 beamline to show that these metals can also find their way into organ tissues. Their results suggest that chronic diseases, such as diabetes, may create conditions in which mildly toxic trivalent chromium (CrIII) particles from replacement joints are reoxidised within the body to form carcinogenic hexavalent chromium (CrVI). Their results have been published in the Journal of Trace Elements in Medicine and Biology.

>Read more on the Diamond Light Source website

Image: Overview of the study (entire figure to see here).