Featured Research

from universities, journals, and other organizations

Plastics In Oceans Decompose, Release Hazardous Chemicals, Surprising New Study Says

Date:
August 20, 2009
Source:
American Chemical Society
Summary:
In the first study to look at what happens over the years to the billions of pounds of plastic waste floating in the world's oceans, scientists are reporting that plastics -- reputed to be virtually indestructible -- decompose with surprising speed and release potentially toxic substances into the water.

A boy in Japan points out Styrofoam debris from the ocean.
Credit: Katsuhiko Saido

In the first study to look at what happens over the years to the billions of pounds of plastic waste floating in the world's oceans, scientists are reporting that plastics — reputed to be virtually indestructible — decompose with surprising speed and release potentially toxic substances into the water.

Reporting at the 238th National Meeting of the American Chemical Society (ACS), the researchers termed the discovery "surprising." Scientists always believed that plastics in the oceans were unsightly, but a hazard mainly to marine animals that eat or become ensnared in plastic objects.

"Plastics in daily use are generally assumed to be quite stable," said study lead researcher Katsuhiko Saido, Ph.D. "We found that plastic in the ocean actually decomposes as it is exposed to the rain and sun and other environmental conditions, giving rise to yet another source of global contamination that will continue into the future."

He said that polystyrene begins to decompose within one year, releasing components that are detectable in the parts-per-million range. Those chemicals also decompose in the open water and inside marine life. However, the volume of plastics in the ocean is increasing, so that decomposition products remain a potential problem.

Each year as much as 150,000 tons of plastic debris, most notably Styrofoam, wash up on the shores of Japan alone, Saido said. Vast expanses of waste, consisting mainly of plastic, float elsewhere in the oceans. The so-called Great Pacific Garbage Patch between California and Hawaii was twice the size of Texas and mainly plastic waste.

Saido, a chemist with the College of Pharmacy, Nihon University, Chiba, Japan, said his team found that when plastic decomposes it releases potentially toxic bisphenol A (BPA) and PS oligomer into the water, causing additional pollution. Plastics usually do not break down in an animal's body after being eaten. However, the substances released from decomposing plastic are absorbed and could have adverse effects. BPA and PS oligomer are sources of concern because they can disrupt the functioning of hormones in animals and can seriously affect reproductive systems.

Some studies suggest that low-level exposure to BPA released from certain plastic containers and the linings of cans may have adverse health effects.

Saido described a new method to simulate the breakdown of plastic products at low temperatures, such as those found in the oceans. The process involves modeling plastic decomposition at room temperature, removing heat from the plastic and then using a liquid to extract the BPA and PS oligomer. Typically, he said, Styrofoam is crushed into pieces in the ocean and finding these is no problem. But when the study team was able to degrade the plastic, it discovered that three new compounds not found in nature formed. They are styrene monomer (SM), styrene dimer (SD) and styrene trimer (ST). SM is a known carcinogen and SD and ST are suspected in causing cancer. BPA ands PS oligomer are not found naturally and, therefore, must have been created through the decomposition of the plastic, he said. Trimer yields SM and SD when it decomposes from heat, so trimer also threatens living creatures.

Funding for Saido's research came from Nihon University.


Story Source:

The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.


Cite This Page:

American Chemical Society. "Plastics In Oceans Decompose, Release Hazardous Chemicals, Surprising New Study Says." ScienceDaily. ScienceDaily, 20 August 2009. <www.sciencedaily.com/releases/2009/08/090819234651.htm>.
American Chemical Society. (2009, August 20). Plastics In Oceans Decompose, Release Hazardous Chemicals, Surprising New Study Says. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2009/08/090819234651.htm
American Chemical Society. "Plastics In Oceans Decompose, Release Hazardous Chemicals, Surprising New Study Says." ScienceDaily. www.sciencedaily.com/releases/2009/08/090819234651.htm (accessed September 17, 2014).

Share This



More Earth & Climate News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins