There is ongoing concern about the potential toxicity of nanoparticles of various materials, and a new study in Chemical Research in Toxicology reports that certain sunscreens that contain zinc oxide nanoparticles may be toxic if ingested.

The research found that particle size affects the toxicity of zinc oxide. Particles smaller than 100 nanometers were slightly more toxic to colon cells than conventional zinc oxide and solid zinc oxide was more toxic than equivalent amounts of soluble zinc. Direct particle to cell contact was required to cause cell death, according to the study.

Astronomers have directly observed the mysterious dark companion in the Epsilon Aurigae star system that has puzzled skywatchers since the 19th century.

Scientists captured close-up pictures of Epsilon Aurigae during its eclipse, which happens every 27 years. "Close up" in this case is a relative term, but the images zoom in enough to show the shape of the dark object's shadow. A new paper in Nature describes the images in detail.

Although beneficial for health in general, a diet high in fruits and vegetables probably won't reduce your risk of cancer, according to a study led by researchers at Mt Sinai Hospital.

The analysis, published in the Journal of the National Cancer Institute, looked at over eight years of dietary data from more than 400,000 people and found that the relationship between high consumption of fruits and vegetables and a reduced risk of cancer is not nearly as strong as previously reported.

Many studies have tested the idea and the results have been mixed; but none of the research so far has been able to confirm a link between fruit and vegetable intake and cancer resistance.

Last year, several studies suggested that individuals in Canada who had previously been vaccinated against seasonal influenza faced an increased risk of pandemic H1N1 (pH1N1).

Those studies have undergone further peer review and researchers writing in PLoS Medicine say their conclusions may be valid, though more research needs to be done to confirm the results.

Russian and US physicists have created a superheavy element made of atoms containing 117 protons that is roughly 40% heavier than lead.  The achievement fills in the final gap on the list of observed elements up to element 118.

The team produced the elusive element 117 by fusing together atoms of calcium and another rare, heavy element known as berkelium. The research will appear in a forthcoming issue of the  Physical Review Letters.

Using CT scans to measure blood flow in the lungs of people who smoke may offer a way to identify which smokers are most at risk of emphysema before the disease damages and eventually destroys areas of the lungs, according to a new study published in PNAS

The study found that smokers who have very subtle signs of emphysema, but still have normal lung function, have very different blood flow patterns in their lungs compared to non-smokers and smokers without signs of emphysema.This difference could be used to identify smokers at increased risk of emphysema and allow for early intervention.