A Tokyo sushi restaurant displays blocks of fat meat tuna cut out from a 269kg bluefin tuna. Yoshikazu Tsuno/AFP/Getty Images hide caption

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Plastic surgeon Amy Pare says it's important for doctors to know what kind of substances patients she's treating might have been exposed to. Susan Philips/WHYY hide caption

itoggle caption Susan Philips/WHYY

Researcher Hans Roy opens a core sample taken from the bottom of the Pacific Ocean. A core sample like this one contained bacteria that settled on the seafloor 86 million years ago. Bo Barker Jorgensen/Science/AAAS hide caption

itoggle caption Bo Barker Jorgensen/Science/AAAS

A working gas well head is fenced in just opposite of a home in Dish, Texas. Dish is about 30 miles north of Fort Worth. David Gilkey/NPR hide caption

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William Reigle has fibrosis, a disease that may be aggravated by nearby fracking. He's one of more than 2 million Pennsylvanians who get their health care from Geisinger Health System. The system wants to use its extensive database of patient records to study the health impact of natural gas production. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR