SACRAMENTO (AP) — Wet wipes, those single-use wet tissues for babies and adults wanting something more than just toilet paper, are the scourge of sewer systems nationwide, according to several cities challenging claims that the products are safe to flush.

Legislation in California that advanced on Thursday would require products that cannot be flushed down the toilet to be clearly labeled as such. Cities including New York and the District of Columbia have also attempted to cut down on what manufactures call “flushable wipes,” saying they can actually clog pipes and require costly repairs.

Some environmentalists worry the wipes end up in waterways, and the bill is among a number of efforts in California to keep harmful products out of the waste stream. A bill to replace California’s faltering recycling program by requiring beverage distributors to buy back their bottles and cans also moved forward in the California Senate on Thursday. Activists and celebrities lobbied in Sacramento on Wednesday for a proposal to cut statewide waste from single use plastics by 75% within the decade.

The California Assembly bill on wet wipes was watered down Thursday amid industry resistance, but only to bring opponents to the table, the bill’s author said.