“At a minimum” (line 41) and “in the team's previous study” (lines 41-43) are examples of

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Americans May Add Five Times More Plastic to the Oceans Than Thought

The United States is using more

plastic than ever, and waste exported for

recycling is often mishandled, according

to a new study.

The United States contribution

to coastal plastic pollution worldwide is

significantly larger than previously

thought, possibly by as much as five

times, according to a study published

Friday. The research, published in Science

Advances, is the sequel to a 2015 paper

by the same authors. Two factors

contributed to the sharp increase:

Americans are using more plastic than

ever and the current study included

pollution generated by United States

exports of plastic waste, while the earlier

one did not.

The United States, which does

not have sufficient infrastructure to

handle its recycling demands at home,

exports about half of its recyclable waste.

Of the total exported, about 88 percent

ends up in countries considered to have

inadequate waste management.

“When you consider how much

of our plastic waste isn’t actually

recyclable because it is low-value,

contaminated or difficult to process, it’s

not surprising that a lot of it ends up

polluting the environment,” said the

study’s lead author, Kara Lavender Law,

research professor of oceanography at

Sea Education Association, in a

statement.

The study estimates that in

2016, the United States contributed

between 1.1 and 2.2 million metric tons of

plastic waste to the oceans through a

combination of littering, dumping and 

mismanaged exports. At a minimum,

that’s almost double the total estimated

waste in the team’s previous study. At the

high end, it would be a fivefold increase

over the earlier estimate.

Nicholas Mallos, a senior

director at the Ocean Conservancy and an

author of the study, said the upper

estimate would be equal to a pile of

plastic covering the area of the White

House Lawn and reaching as high as the

Empire State Building.

The ranges are wide partly

because “there’s no real standard for

being able to provide good quality data on

collection and disposal of waste in

general,” said Ted Siegler, a resource

economist at DSM Environmental

Solutions, a consulting firm, and an

author of the study. Mr. Siegler said the

researchers had evaluated waste-disposal

practices in countries around the world

and used their “best professional

judgment” to determine the lowest and

highest amounts of plastic waste likely to

escape into the environment. They settled

on a range of 25 percent to 75 percent.

Tony Walker, an associate

professor at the Dalhousie University

School for Resource and Environmental

Studies in Halifax, Nova Scotia, said that

analyzing waste data can amount to a

“data minefield” because there are no

data standards across municipalities.

Moreover, once plastic waste is shipped

overseas, he said, data is often not

recorded at all.

Nonetheless, Dr. Walker, who

was not involved in the study, said it

could offer a more accurate accounting of

plastic pollution than the previous study,

which likely underestimated the United

States’ contribution. “They’ve put their

best estimate, as accurate as they can be

with this data,” he said, and used ranges,

which underscores that the figures are

estimates.

Of the plastics that go into the

United States recycling system, about 9

percent of the country’s total plastic

waste, there is no guarantee that they’ll

be remade into new consumer goods. New

plastic is so inexpensive to manufacture

that only certain expensive, high-grade

plastics are profitable to recycle within the

United States, which is why roughly half

of the country’s plastic waste was shipped

abroad in 2016, the most recent year for

which data is available.

Since 2016, however, the

recycling landscape has changed. China

and many countries in Southeast Asia

have stopped accepting plastic waste

imports. And lower oil prices have further

reduced the market for recycled plastic.

“What the new study really underscores is

we have to get a handle on source

reduction at home,” Mr. Mallos said. “That

starts with eliminating unnecessary and

problematic single-use plastics.”

From: https://www.nytimes.com/2020/10/30/