Using Rust to Remove Arsenic From Water

  • Scientists have been using tiny particles of rust to draw arsenic out of water (Source: Roger McLassus at Wikimedia Commons)

You might be surprised to hear that a lot of drinking water has arsenic in it. It’s a problem all over the globe, especially when drinking water comes from deep under the ground. Julie Grant reports that some researchers are using tiny particles – at the nano-scale – and plain old rust, to remove arsenic from the water:

Transcript

You might be surprised to hear that a lot of drinking water has arsenic in it. It’s a problem all over the globe, especially when drinking water comes from deep under the ground. Julie Grant reports that some researchers are using tiny particles – at the nano-scale – and plain old rust, to remove arsenic from the water:

You can’t see, smell, or taste arsenic – but prolonged exposure to it can lead to skin discoloration and even cancer.

Vicki Colvin studies chemistry and nanotechnology at Rice University in Houston.

She says arsenic has a chemical bond with rust – and sticks to it. So they’ve been using tiny particles of rust to draw arsenic out of water in the lab.

Now Colvin says they’re working with a city in Mexico. They’re trying to make what they call nano-rust in the field, so the city can cheaply remove arsenic from its water.

“So, we’ve developed procedures and processes that help people make nano-rust not at a major university with a nanotechnology facilty. But you know literally in a restaurant setting, more maybe in a ceramics factory.”

Colvin says they will be experimenting in Mexico over the next two years.

For The Environment Report, I’m Julie Grant.

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Neighbors Reclaim Abandoned Urban Land

  • Maria Graziani (in green) teaches neighborhood kids about farming. (Photo by Lisa Ann Pinkerton)

It can take years for city government to demolish or develop abandoned property. In one urban neighborhood, a group of neighbors has found a new way to reclaim land that has been left behind. The Great Lakes Radio Consortium’s Lisa Ann Pinkerton has their story:

Transcript

It can take years for city government to demolish or develop
abandoned property. In one urban neighborhood, a group of neighbors has
found a new way to reclaim land that has been left behind. The Great Lakes
Radio Consortium’s Lisa Ann Pinkerton has their story:


Maria Graziani’s house was built on a hillside. At the top of the hill, people have dumped old refrigerators, broken air conditioners, dried up paint cans, worn out tires… lots and lots of junk on the abandoned property. Last year she brought her neighbors and the city together to clean up the mess. This year, she’s farming it.


(Sound of rusty metal squeaking)


On her front porch, she lifts a manual reel mower onto her shoulder to carry to the top of the hill. She’s made this trip so many times before, she’s carved a path through the weeds. On her way, she has to step over and around various pieces of rusted junk.


“There’s like a wooded area that’s owned by the city that, I guess, used to be people’s backyards because there’s trash and cars up here.”


Graziani’s not your typical urban developer. Her orange knitted headband keeps her brown dreadlocks at bay, her paint-splattered overalls are ripped, and her pockets are stuffed with tools. At the top of the hill, she leans on her knees to catch her breath. Ahead of her, is a field covered by invasive knotweed.


“This is where the farm property starts.”


Despite field’s condition, it has a breathtaking view. Nearly the entire Pittsburgh skyline is framed by trees and lit by a gold setting sun.


“It’s one point seven acres, nineteen lots that the Urban Redevelopment Authority and the city own.”


Graziani formed a non-profit organization to get foundation money to pay for the block and the back taxes. In five years, it will all belong to The Healcreast Urban Community Farm.
The farm doesn’t have a lot of rules. If you help out, you can have some food.
If you’re needy, there’s food available for the asking. Besides the theft of the farm’s tomato plants, Graziani says it works pretty well.


As the sun falls and the evening cools off, another workday begins.
Volunteers trudge up the hill from every conceivable direction.


(Sound of shovels, talking)


The volunteers say once they heard about the urban farm they wanted to help. Even if they weren’t sure how.


VOLUNTEER 1: “I know close to nothing about farming, so I just need to learn – I need to dig in and learn how to do it.”


VOLUNTEER 2: “I work for the Bloomfield Garfield Corporation So that’s how I learned about this; it’s a small office.”


VOLUNTEER 3: “It seemed fairly absurd at first, but it makes a whole lot of sense when you think about it, with all the vacant spaces in town that aren’t being used.”


Everyone picks a spot and starts digging. Immediately they’ve got a problem: they’ve hit concrete. It’s the foundation of a demolished house. That’s only one of the obstacles the Healcrest farmers have faced. The volunteers had an easy time with their first garden. Not much junk was dumped in that area. But the rest of the property is contaminated with arsenic and lead, but Graziani has a plan.


“I would like to till it and put in some dwarf sunflowers. Which I want to use for phyto-remediation.”


The sunflowers will draw up the contaminants into their roots. In the fall, farmers will pull up the plants – roots and all – and dump them at a hazardous waste facility.


(Sound of rain)


Two days later it’s another workday. And it’s raining. But the Healcreast farmers hardly notice.
Because they uncovered the foundation of an old house, they’ve decided to build raised beds.
They layer peat moss, compost, and topsoil into mounds. And even though it’s raining the sun breaks through for a moment.


“And I think that I see it; it’s right there! So we’ve got a rainbow, just kind of right over the hill, it’s quite gorgeous.”


As summer has progressed, all kinds of vegetables are growing strong: peppers, collard greens, corn, squash. With a grant from the Health Department, Graziani can pay junior high school students a little bit of cash to help her once a week. They’re kids from the neighborhood, who’ve only known the hilltop as a dump. Soon, Graziani, the kids, and the volunteers, will have a harvest on the hilltop.


For the GLRC. I’m Lisa Ann Pinkerton.

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Solution for Arsenic in Drinking Water?

  • Researchers from the University of Illinois have discovered a way to remove arsenic from drinking water at its source. (photo by David Guglielmo)

Researchers believe they have found a way to reduce
arsenic levels in drinking water. They say, for people to drink water from wells or aquifers, the solution starts at the source. The Great Lakes Radio Consortium’s Jeff Bossert explains:

Transcript

Researchers believe they have found a way to reduce arsenic levels in drinking water. They say, for people to drink water from wells or aquifers, the solution starts at the source. The Great Lakes Radio Consortium’s Jeff Bossert explains:


Chronic exposure to arsenic in drinking water has been linked to a variety of health concerns, including hypertension, cardiovascular disease, and cancer.


Researchers from the University of Illinois collected groundwater samples from 21 wells. They found that the wells with almost no arsenic in the water also contained high levels of sulphate-reducing bacteria, which convert the arsenic into a solid, where it drops out of the water. Dr. Craig Bethke led the study.


“What we’re saying is that if there’s sulfate in the water, then there’s probably sulfate-reducing bacteria active in the subsurface, and that means that a simple field test, which is very inexpensive and very rapid to protect sulfate, could identify safe water sources.”


Bethke says places where aresenic levels are high, sulphate salts, such as gypsum and calcium sulphate, can be injected underground to reduce arsenic levels.


Researchers say this information could prove to be invaluable in places where aresenic contamination is a major problem, including parts of the U.S., Australia, and Mongolia. The researchers’ findings were published in the journal Geology.


For the Great Lakes Radio Consortium, I’m Jeff Bossert.

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Treated Lumber a Health Hazard?

A just-released study by two environmental groups has found high levels of arsenic on the surface of pressure-treated wood products. The Environmental Working Group and the Healthy Building Network tested pressure-treated wood purchased from home improvement stores in 13 cities. In releasing their findings, the groups are calling for a ban on the use of the lumber in construction. Their findings add to the growing concern about the safety of the chemicals used to treat this wood. Those chemicals are now being re-evaluated by both the Canadian and American governments. But as the Great Lakes Radio Consortium’s Karen Kelly reports, the two governments are approaching the issue differently:

Transcript

A just released study by two environmental groups has found high levels of arsenic on the surface of pressure-treated wood products. The Environmental Working Group and the Healthy Building Network tested pressure-treated wood purchased from home improvement stores in 13 cities. In releasing their findings, the groups are calling for a ban on the use of the lumber in construction. Their findings add to the growing concern about the safety of the chemicals used to treat this wood. Those chemicals are now being re-evaluated by both the Canadian and American governments. But as the Great Lakes Radio Consortium’s Karen Kelly reports, the two governments are approaching the issue differently.


For years, Don Houston at the Canadian Institute of Child Health has been calling for warning labels on pressure-treated wood. The lumber is used in playground structures and picnic tables throughout North America. And it’s treated with a preservative called Chromated Copper Arsenate, which protects the wood from insects and fungi. The preservative is made from arsenic, chromium and copper. And Houston says children who are exposed to the wood may be exposed to those chemicals, as well.


“It’s not just children’s play structures. I’d rather suspect even more problematic is the deck that’s on the back of their house because often times children spend more time there. It’s all sorts of structures that are put in outdoors – decks, balconies, retaining walls; even the telephone pole that might be in a schoolyard might be problematic.”


Houston says the problem arises when arsenic and chromium, which are both carcinogens, remain on the surface of the wood. A study of ten playgrounds conducted by Health Canada in the late 1980’s detected both substances on the surface of play structures made with pressure treated wood. Arsenic and chromium were also found in the nearby soil. Health Canada warns people who work with pressure-treated wood to wear gloves and a mask and to thoroughly wash clothing and exposed skin once they’re finished. The agency also warns against burning pressure treated wood. But Houston says there are still no guidelines for children.


“It doesn’t make a lot of sense for the guy who’s building it to use gloves and then the child ten minutes after it’s built to be walking over it and running on it barefoot and having greater potential health impact from the exposure.”


But scientists at Health Canada say the research findings have been mixed. They point to studies conducted by the U.S. EPA in the late 1980’s that found minimal health risks. Now, fifteen years since they last evaluated these chemicals, both Health Canada and the EPA are taking another look. The update is required by law in both countries. Richard Martin is a toxicologist at Health Canada’s Pest Management Regulatory Agency. He says the presence of arsenic is not always a cause for concern.


“Although there’s a number of reports out there of arsenic being found in soil, and although they’re useful, arsenic is found in all soil. So we need to go the extra step to determine to what extent there’s potential for exposure to children and that type of thing.”


Martin says his agency is reviewing research to determine the effect of exposure on both adults who work with cca-treated wood and children who play near it. But the U.S. Environmental Protection Agency is taking the review a step further. Jim Jones, the deputy director of the EPA’s office of pesticide programs, says they’re concentrating on the exposure to children first.


“It was the children’s exposure through cca-treated wood we think are the most important to look at as they’re the group in the population that is likely to have the greatest exposures, just because of the way in which they interact with playground equipment and on decks.”


The EPA also plans to take soil samples near cca-treated wood structures in 75 playgrounds around the United States. And it’s considering a recommendation that people apply sealants to pressure-treated wood in the interim. The EPA’s scientific advisory panel suggested the agency take that measure. The EPA and Health Canada are collaborating on the re-evaluation – sharing their findings and their recommendations. Don Houston of the Canadian Institute of Child Health hopes that will lead to legislation in both countries that will restrict the use of this lumber in places where children play. The EPA and Health Canada are expected to announce their recommendations next spring.


For the Great Lakes Radio Consortium, I’m Karen Kelly.

Commentary – Epa Misses an Opportunity

Last month (April) the U.S. Environmental Protection Agency decided
against regulating ash and sludge from coal-burning power plants as a
toxic hazardous waste. Instead, the EPA will develop voluntary coal-ash
disposal standards. Great Lakes Radio Consortium commentator Suzanne
Elston says the move is a major setback in the war against global
warming:

Scientists Push for Tougher Arsenic Standards

Groundwater in some Great Lakes states has been found to meet or exceed
acceptable levels of naturally occurring arsenic. Growing concern about
the health effects of arsenic consumption recently prompted the U-S
Academy of Sciences to recommend that the federal government create more
stringent standards for human consumption of arsenic. The Great Lakes
Radio Consortium’s Marisa Helms has the story:

EPA Re-Examines Effects of Pesticides on Children

For the past few years, environmentalists have been warning consumers that pesticides applied to fruits and vegetables could be extremely dangerous to children. Soon, the Environmental Protection Agency will tackle the issue. Armed with a new federal law, the EPA is taking a fresh look to see if pesticides applied to produce carry health hazards. The Great Lakes Radio Consortium’s Julie Edelson Halpert has more: