Hansi Lo Wang

A group of Democratic senators have introduced a bill on Tuesday that would require the U.S. census and the country's largest survey to start directly asking about sexual orientation and gender identity.

If the Census Equality Act becomes law, sexual orientation and gender identity questions would have to be added to forms for the census by 2030 and for the American Community Survey — a survey that about 1 in 38 households are required by federal law to complete every year — by 2020.

NPR's "Take A Number" series is exploring problems around the world — and solutions — through the lens of a single number.

One of the places many people are first prescribed opioids is a hospital emergency room. But in one of the busiest ERs in the U.S., doctors are relying less than they used to on oxycodone, Percocet, Vicodin and other opioids to ease patients' pain.

President-elect Donald Trump said he's finishing a plan to replace the Affordable Care Act with a proposal that would provide "insurance for everybody," according to a report by The Washington Post.

In the marshy woods of Secaucus, N.J., a mosquito can make a happy home.

With water and shade under a canopy of maple trees, you could barely ask for more to start your own bloodsucking family.

For Gary Cardini, though, this is a battleground.

"You want to get them in the water before they're flying," explains Cardini, who supervises the field team for Hudson County Mosquito Control. "In the water, they're captive. You know where they are."

There's a new tool for battling the opioid epidemic, compressed inside long, metal tanks at an emergency room in Paterson, N.J.

It's laughing gas, also known as nitrous oxide.

Water safety concerns aren't just in Flint, Mich., these days. Communities in three states in the Northeast have found elevated levels of a suspected carcinogen — perfluorooctanoic acid, or PFOA.

Used to make Teflon, the chemical has contaminated water supplies in New York, New Hampshire and Vermont.

After a four-month ban in the village of Hoosick Falls, N.Y., the New York State Department of Health declared the water safe to drink and cook with again on Wednesday. A temporary filtering system has brought PFOA levels down to nondetectable levels for weeks.

A street drug made of various chemicals sprayed on tea leaves, grass clippings and other plant material continues to send thousands of people suffering from psychotic episodes and seizures to emergency rooms around the country.

In 2015, calls to poison control regarding the drug already have almost doubled, compared to last year's total, and health professionals and lawmakers are struggling to keep up with the problem.