Why did researchers take a knife to a cute little plastic gingerbread man? To make him give up the source of his toxic fumes. Or so explained Bill Doucette, this morning, in a particularly entertaining session at the Society for Toxicology and Environmental Chemistry’s annual meeting. But the underlying message that this Utah State University scientist brought home to his audience was anything but funny. He graphically illustrated that hidden dangers may lurk in surprising places.

No one would choose to eat polychlorinated biphenyls, or PCBs — yet we unwittingly do. And a new study finds that the cost of their pervasive contamination of our food supply can be elevated blood pressure, a major risk factor for heart disease.

Prevention could begin with lifestyle in younger years, one researcher says during the American Public Health Association meeting.

Weather-monitoring stations in the Lower 48 have been logging record daily highs in temperature at twice the pace of record lows. Yet more evidence of climate warming. Many people have pointed to colder than normal winters — or summers — as evidence that global warming is a myth. Climatologists have countered that weather, the meteorological features that we experience at any given hour or day, may show anomalies even as Earth’s overall climate warms. So weather can locally mask the planet’s overall slowly rising fever. Except that any such mask appears to be disappearing throughout most of the United States, according to a new study.

Philadelphia — On brainstorming possible keynote speakers for a major public health conference, the granddaughter of ocean giant Jacques Cousteau does not exactly stand out. But in Philadelphia on Sunday, filmmaker and diver Celine Cousteau stood before the 11,000 or so attendees of the American Public Health Association's annual meeting to explain just why exactly she was there to give the opening session's address.

Negotiators representing 181 nations completed their final prep work in Barcelona, Spain, last Friday, on a new climate treaty — one that they hope to build a month from now at a major conference in Copenhagen, Denmark. But at least one scientist worries that what comes out of the Copenhagen deliberations may not have sufficient coordination and strength to meet the challenges that Earth’s climate has begun throwing at us.

Three groups of healthcare professionals sent a letter to President Obama yesterday asking that he instruct his administration to revise federal flu-mask guidance. What these groups want: formal recognition that two studies last month showed conventional surgical masks are about as protective as the fancy — but much more expensive — N95 respirators in limiting H1N1 infection.

A spot of encouraging news emerged yesterday on the medical-isotope front. The House of Representatives voted 440 to 17 in favor of a bill to reestablish domestic production of molybdenum-99. It’s the feedstock for the most heavily used nuclear agent in diagnostic medicine.

Efforts to get the Large Hadron Collider up and running just encountered a temporary snag, according to yesterday's online edition of The Times of London. A crusty chunk of bread “paralysed a high voltage installation that should have been powering the cooling unit.”

BLOG: Art and science meld during a musical performance for the Fermi Gamma-ray Space Telescope

Featured blog: Researchers are working to catalog the DNA sequences of just about every vertebrate genus.