Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




FROTH AND BUBBLE
Legacy Soil Pollution Higher lead levels may lie just below surface
by Staff Writers
Providence RI (SPX) Sep 24, 2013


Prevailing winds can carry flakes of lead paint farther downwind, especially from taller towers. Researchers suggest monitoring contamination by taking samples at various depths - and more than 200 feet from old water towers.

newly published analysis of data from hundreds of soil samples from 31 properties around southern Rhode Island finds that the lead concentration in soil at the surface is not always a reliable indicator of the contamination a foot deeper. The study, led by Brown University Superfund Research Program researchers at the request of the Rhode Island Department of Health (RIDOH), informs ongoing efforts to assess the impact of the state's legacy of lead-painted water towers.

Towers all over the state, including at six sites analyzed in the study, were often coated with lead paint until the practice stopped in 1979. Over time paint could flake off onto properties below.

In 2004, residents near a water tower in Westerly, known as "Site 19," learned that some local properties become contaminated, leading to investigations that highlighted differences in the standards of RIDOH and the Rhode Island Department of Environmental Management (RIDEM).

One key difference between the regulations is whether they require looking at depths below the soil surface to determine whether remediation is required. RIDEM requires that but RIDOH does not.

The main finding of the new study, published in the journal Science of the Total Environment, is that solely looking at surface contamination would have missed higher lead concentrations at lower depths in soil core samples from four of the 31 properties.

In other words, samples on 13 percent of the properties could have been classified by RIDOH standards as "lead-safe," when higher than lead-safe concentrations lurked either six or 12 inches beneath the surface. (RIDOH defines lead-safe as a lead concentration of more than 150 milligrams per kilogram in soil but less than 400 milligrams per kilogram).

Importantly, because multiple samples were taken on each property, no property was ever actually misclassified, according to the analysis, said lead author and Brown researcher Marcella Thompson. In all, the study considered data from 498 samples, including 348 with soil at depths of six and 12 inches.

Still, Thompson said, the findings are important because the health stakes of exposure to lead are so high. Lead exposure has known neurobehavioral and neurodevelopmental consequences for people and animals. For every 1,000 mg/kg increase in lead-soil contamination, blood lead levels can rise 1 ug/dL to 5 micrograms per deciliter, Thompson said. The greater the exposure, the greater the potential for harm, particularly to children.

"Especially when you are talking about children's health and the health of the people who live there, one mistake is one too many," Thompson said. "Better safe than sorry. If there is a potential for [misclassification] to occur, we should take the more conservative route."

A surprising finding of the study, Thompson said, was that significant amounts of lead were sometimes able to accumulate as far as 400 hundred feet from the water towers. The direction-specific patterns she and her co-authors observed suggest that wind carried paint flakes over those distances.

"In general it became rather apparent which way the wind blew," she said.

Study's origin and impact
Bob Vanderslice, toxicologist and team lead for Healthy Homes and Environment at RIDOH, said the department asked the researchers to conduct the study based on the questions posed by Westerly residents in the vicinity of the town's water tower.

"Residents questioned the effectiveness of the soil sampling methodology used to investigate the contamination," he said. "Core samples up to two feet deep are used by the DEM to investigate environmental contamination. The top one inch of soil is sampled by the Department of Health to investigate lead contamination of residential properties that pose risks of childhood lead poisoning."

Now that the study is done, Vanderslice said, it confirms RIDEM's methodology and will inform that of RIDOH.

"The results of this study indicate that concerns about the DEM methodology were not warranted. The DEM sampling methodology correctly identified all properties that needed remediation," he said.

"The study provides recommendations for the Department of Health to consider in revising its Rules and Regulations for Lead Poisoning Prevention, including to evaluate soil standards to ensure that they protect children from reaching blood levels of five micrograms per deciliter, the more recently adopted level of concern, and to ensure that the sampling methodology adequately addresses the possibility that surface soil samples may not identify lead hazards at depth."

Thompson said the study provides a good example of how policies such as those of RIDOH, which are informed by sound scientific evidence and theory, can still be further informed by real-world field assessment, a process called "practice-based evidence."

The study's recommendations for future contamination monitoring efforts in Rhode Island include sampling soil at multiple depths and farther away than 200 feet, depending on prevailing winds and tower height. The authors also call for state agencies to sample from properties around other old water towers, to adopt more uniform definitions of terms, and to update standards to reflect new stricter exposure guidelines from the U.S. Centers for Disease Control and Prevention.

In addition to Thompson, other authors on the paper are Kim Boekelheide, professor of pathology and laboratory medicine at Brown, and University of Rhode Island nursing student Andrea Burdon.

The National Institutes of Health National Institute of Environmental Health Sciences fund the Brown University Superfund Research Program with grant P42-ES013660.

.


Related Links
Brown University
Our Polluted World and Cleaning It Up






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





FROTH AND BUBBLE
PNG makes BHP liable for environmental damage from mine
Sydney (AFP) Sept 19, 2013
Papua New Guinea's government wrested full control of the controversial Ok Tedi copper and gold mine and quashed former owner BHP Billiton's legal immunity for environmental damage, officials said Thursday. Prime Minister Peter O'Neill moved late Wednesday to give the government 100 percent ownership of Ok Tedi, which was involved in a major waterways pollution scandal in the 1990s. Orig ... read more


FROTH AND BUBBLE
US Navy moves to tighten security checks after shooting

Australians should be told of boat turn-backs, ex-navy chief

Obama: Navy Yard shooting must inspire gun law change

In Mexico, storms dredge up human errors

FROTH AND BUBBLE
New Model Should Expedite Development of Temperature-Stable Nano-Alloys

Balkans gold rush prompts pollution fears

Environmentally friendly cement is stronger than ordinary cement

X-ray science taps bug biology to design better materials and reduce pollution

FROTH AND BUBBLE
Spinning CDs to Clean Sewage Water

Current pledges put over 600 million people at risk of higher water scarcity

Algorithm finds missing phytoplankton in Southern Ocean

Worst watershed stresses may become the new normal

FROTH AND BUBBLE
Achilles' heel of ice shelves is beneath the water, scientists reveal

Research: Strong winds may contribute to more sea ice in Antarctica

Arctic Sea Ice Minimum in 2013 is Sixth Lowest on Record

Russia mulls piracy charge against Greenpeace protesters

FROTH AND BUBBLE
China takes 12.5% stake in Russian potash giant: company

Smithfield agrees to takeover by China's Shuanghui

Research minimizes effects of federal produce standards on mushroom industry

Brazil rancher's conviction upheld in US nun's death

FROTH AND BUBBLE
Seismologists puzzle over largest deep earthquake ever recorded

GOES Satellite Catches Three Tropical Cyclones in One Shot, Sees Gabrielle Absorbed

Heavy toll feared as big quake hits Pakistan

Heavy rains kill 36 in Vietnam, Cambodia

FROTH AND BUBBLE
Akgeria: Bouteflika seeks to outflank rival generals

160 UN peacekeepers desert Mali posts: military

Three Ivorian police killed in attacks

Uganda suspends 24 officers over Somalia corruption

FROTH AND BUBBLE
Findings in Middle East suggest early human routes into Europe

Paleorivers across Sahara may have supported ancient human migration routes

Orangutans plan their future route and communicate it to others

New evidence that orangutans and gorillas can match images based on biological categories




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement