Featured Research

from universities, journals, and other organizations

Chesapeake Bay pesticides: Some diminish, some persist

Date:
July 9, 2011
Source:
USDA/Agricultural Research Service
Summary:
Scientists are identifying factors that influence pesticide levels in the Chesapeake Bay airshed, including traces of "legacy" pesticides that still linger even though they are no longer being used.

ARS chemists Cathleen Hapeman (left) and Laura McConnell have found that traces of some "legacy" pesticides that are no longer used linger in the Chesapeake Bay airshed.
Credit: Peggy Greb

Scientists with the U.S. Department of Agriculture (USDA) are identifying factors that influence pesticide levels in the Chesapeake Bay airshed, including traces of "legacy" pesticides that still linger even though they are no longer being used.

Related Articles


Agricultural Research Service (ARS) chemists Laura McConnell and Cathleen Hapeman obtained weekly air samples and rain samples for precipitation events from 2000 to 2003 at three sites in Maryland and Delaware. Both scientists work at the ARS Environmental Management and Byproduct Utilization Laboratory in Beltsville, Md. ARS is USDA's chief intramural scientific research agency.

The samples were tested for several types of legacy pesticides, including chlordane and related chemical products such as heptachlor and breakdown products of chlordane; lindane; aldrin and dieldrin; DDT and its degradation products (DDD and DDE); and mirex. Nearly all the air samples contained lindane and chlordane products, and pesticides measured at the highest mean concentrations were dieldrin and DDE.

The scientists found that some of the legacy pesticides detected in the samples -- including chlordane compounds, lindane, DDE, and dieldrin -- came from local and regional sources, possibly from contaminated soils. When disturbed, the generally sandy soils on the Delmarva Peninsula are more likely to release pesticides than soils that contain higher levels of organic carbon. But the researchers also concluded that most of the lindane, heptachlor, and many of the chlordanes detected in the air samples came from sources more than 60 miles away.

Modeling results indicated that the variability in air temperature and wind conditions only accounted for 30 to 60 percent of the variability in compound levels. And there was some good news: With the exception of dieldrin, the half-life values measured for the pesticides in the samples indicated that legacy pesticide levels were decreasing over time in the Delmarva.

Results from this study, which support the USDA priority of promoting sustainable agriculture, were published in Science of the Total Environment and Environmental Toxicology and Chemistry.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Ann Perry. Note: Materials may be edited for content and length.


Cite This Page:

USDA/Agricultural Research Service. "Chesapeake Bay pesticides: Some diminish, some persist." ScienceDaily. ScienceDaily, 9 July 2011. <www.sciencedaily.com/releases/2011/07/110707111031.htm>.
USDA/Agricultural Research Service. (2011, July 9). Chesapeake Bay pesticides: Some diminish, some persist. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2011/07/110707111031.htm
USDA/Agricultural Research Service. "Chesapeake Bay pesticides: Some diminish, some persist." ScienceDaily. www.sciencedaily.com/releases/2011/07/110707111031.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Lava on Track to Hit Hawaii Market

Raw: Lava on Track to Hit Hawaii Market

AP (Dec. 19, 2014) Lava from an active volcano on Hawaii's Big Island slowed slightly but stayed on track to hit a shopping center in the small town of Pahoa. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Birds Might Be Better Meteorologists Than Us

Birds Might Be Better Meteorologists Than Us

Newsy (Dec. 19, 2014) A new study suggests a certain type of bird was able to sense a tornado outbreak that moved through the U.S. a day before it hit. Video provided by Newsy
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Arctic Warming Twice As Fast As Rest Of Planet

Arctic Warming Twice As Fast As Rest Of Planet

Newsy (Dec. 18, 2014) The Arctic is warming twice as fast as the rest of the planet, thanks in part to something called feedback. 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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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