The amount of household rubbish being rejected for recycling in England has increased by 84% over the past four years, government figures show.
A BBC Freedom of Information request found councils were unable to recycle 338,000 tons of waste in 2014-15 – up from about 184,000 tons in 2011-12.
But Department for Environment data shows total recycled waste rose from 10.7m to 11m tons a year in the period.