50 years ago, scientists discovered the Great Pacific Garbage Patch

Setting sail into a plastic sea — Science News, February 10, 1973

Scientists on an oceanographic voyage in the Central North Pacific last August became startled about the number of manmade objects littering the ocean surface. [Far from civilization and shipping lanes], they recorded 53 manmade objects in 8.2 hours of viewing. More than half were plastic. They go on to compute that there are between 5 million and 35 million plastic bottles adrift in the North Pacific.

Update
The Great Pacific Garbage Patch is larger now than it was in 1973, containing an estimated 1.8 trillion pieces of plastic within an area twice the size of Texas (SN Online: 3/22/18). In recent years, marine biologists have started seeing evidence that garbage is disrupting ocean ecosystems. For instance, large pieces of trash have helped species cross into new territories (SN: 10/28/17, p. 32). But an even greater threat may lurk beneath the waves. Tiny bits of plastic concentrate hundreds of meters deep where they can be eaten by filter feeders and potentially make their way into the guts of larger predators (SN: 7/6/19 & 7/20/19, p. 5).