Not plastic bottles of water or soda, but soft and flexible things like shower curtains. They're also in shampoos and carpeting.
Phthalates are so ubiquitous, we all have traces in our bodies.
Recently the Environmental Protection Agency, EPA, put phthalates on a list of chemicals that "may present a risk" to the environment or human health. That's because they disrupt hormone activity and some preliminary studies show that they may be causing a slow and steady demasculinizing of men.
But if phthalates were on trial, a jury might find the evidence against them conflicting and inconclusive. And yet last year Congress took action, doing what Europe had already done: it banned certain phthalates in children's toys.
Congress came under pressure to act because of a study by Dr. Shanna Swan, an epidemiologist at the University of Rochester Medical School. Dr. Swan compared the levels of phthalates in a group of pregnant women with the health of the baby boys they gave birth to.
Swan told "60 Minutes" correspondent Lesley Stahl she found that the higher the level of phthalates in the mother's urine during pregnancy, the greater the problems occurred in young boys.
Asked what she found in babies, Swan said, "We found that the baby boys were in several subtle ways less completely masculine."
Dr. Howard Snyder, a pediatric urologist at Children's Hospital in Philadelphia, says Swan's findings line up with what he's seeing in newborn baby boys: an alarming increase in deformed sex organs.
Dr. Snyder operated on one-year-old Griffin to correct something called "hypospadias," a birth defect that causes problems in urination.
"He's a healthy little guy who's, I think, going to get through the rest of life aiming without any difficulty at all," Snyder told Stahl.
"We hear that there are more and more and more cases of hypospadias. Are you seeing a lot?" Stahl asked.
"Thirty, 40 years ago, the best data we had then was that hypospadias occurred in about one in every 300 live male births. It's up to now about one in 100. So there's been a threefold increase," Snyder explained.
There's also been a two-fold increase in another abnormality: un-descended testicles. Snyder says something seems to be interfering in the womb with the production of testosterone, causing the male organs to form improperly. And he suspects it may be phthalates.
"You're moving in on these chemicals," Stahl remarked. "You don't think whatever we're seeing is smoking or diet or something else?"
"I think it's the chemical exposure that are most telling," Snyder replied.
He points to studies beyond Shanna Swan's that seem to link phthalates to low sperm counts and low testosterone levels in adult males.
"There's just too much incremental data that has built up to be ignored. I think it's a real phenomenon. I really, honestly do," Snyder said.
Look around Dr. Snyder's hospital and you see how phthalates can make their way into our bodies. They're in the IV bags and the tubing for instance. When premature babies - hooked up like this - were studied, researchers found that their phthalate levels soared.
Who would've thought chemicals embedded in plastic leach out. Well they do, in small amounts. But studies are beginning to suggest that even small amounts can have an effect. If it is shown definitively that phthalates are dangerous, it won't be easy to get rid of them.