(WHTM) — Almost every one of us has a recycling bin where we live. But how many of us know exactly what is allowed in one? And how many of us have wondered how much good recycling does these days?

“We get 5,000 bowling balls every year in our recycling facilities. None of these balls are accepted in any recycling program,” Brett Bell, Vice President of Recycling for WM, formerly known as waste management, said.

Most of us know bowling balls are not accepted in recycling bins, but Bell says there are many other items that are not allowed in the bins either.

“Batteries, lithium-ion batteries, [and] propane tanks. These can actually cause explosions or fires within our recycling facilities and the trucks that carry them,” Bell said.

Bell says many people do not know a lot of other stuff we should know about recycling.

“All recyclables should be loose, clean, and dry,” Bell said.

But Bell said that cleaning does not mean wasting water washing those items out.

“Don’t spend a lot of time trying to get the last scoop out. Just empty it out as much as it can and throw it in the bin,” Bell said. “Just take out that last slice of pepperoni or cheese pizza [out of the box] and throw that away. We don’t want the pizza, but we do want the box.”

But how much good do all the pizza boxes, cans, and bottles we recycle even do?

Erica Smithwick, the director of Penn State’s Earth and Environmental Systems Institute, says we have already recycled as much plastic at this point in the year as the world can use all in a whole year.

Smithweick says there is a reason people like her say to “reduce, reuse, recycle” in that order.

“First, it’s really important to use less. That really should come after reducing and reusing – recycling is the third option. But it’s a very important option because it can take items out of the waste stream. Every recycling community in the US accepts paper, cardboard, plastic bottles, and cans,” Smithwick said.

So what do you do with the rest of it?

“You definitely should always check with your local programs and what they accept and what they do not accept,” Bell said.