2.6 billion pounds of arsenic and other toxic pollutants flooded over nearby farmland and into the river.
(Photo courtesy of the Tennessee Department Of Health)
When a dam broke a year ago in Kingston,
Tennessee, the town experienced one
of the biggest environmental disasters
in US history. Billions of gallons
of waterlogged coal ash from a nearby
power plant streamed into the Emory
River. Tanya Ott reports
the contamination was even greater
than originally thought:
Transcript
When a dam broke a year ago in Kingston,
Tennessee, the town experienced one
of the biggest environmental disasters
in US history. Billions of gallons
of waterlogged coal ash from a nearby
power plant streamed into the Emory
River. Tanya Ott reports
the contamination was even greater
than originally thought:
2.6 billion pounds of arsenic and other toxic pollutants. That’s how much
contamination flooded over nearby farmland and into the river.
That comes
from a report by the Environmental Integrity Project.
Eric Schaeffer is the
project’s Executive Director and a former official with the Environmental
Protection Agency. He says 2.6 billion pounds is more than the total
discharges from all U-S power plants last year.
“The toxic metals, once they get into the environment,
and especially once they get into sediment, are notoriously difficult to
clean up.”
Difficult and expensive. The Tennessee Valley Authority puts the price tag
at about a billion dollars.
The EPA was supposed to propose tougher
disposal standards for toxic ash by the end of 2009. But the agency delayed
that decision.
Some people say wastewater treatment plants might not be doing a good job taking out pollutants like household chemicals and pharmaceuticals.
(Photo courtesy of the US EPA)
A new study is looking at just
how well wastewater treatment
plants remove household chemicals
and pharmaceuticals from water.
Samara Freemark reports
on why some researchers are worried
that the plants aren’t doing a good
enough job:
Transcript
A new study is looking at just
how well wastewater treatment
plants remove household chemicals
and pharmaceuticals from water.
Samara Freemark reports
on why some researchers are worried
that the plants aren’t doing a good
enough job:
Most wastewater treatment plants clean water with a mix of chemicals and bacteria. But that process is decades-old. And it was designed mostly to deal with industrial pollutants.
Some people say treatment plants might not be doing a good job taking out other pollutants like household chemicals and pharmaceuticals. In fact, the treatment process can actually cause many of these pollutants to mutate – for example, some detergents break down into compounds that cause reproductive problems.
Anthony Hay is studying the issue at Cornell University.
“Hopefully they’re degraded into something non-toxic, but in some cases microbial degradation of some pollutants can actually make things worse. We need to understand what those changed products do, how they behave, and what risks they might pose.”
That’s what Hay hopes his study will help clarify.
Pharmaceuticals and other toxins have been found in lakes like this one, Lake Champlain. (Photo by Kinna Ohman)
Less than ten years ago, the U.S. Geological Survey found household drugs and
chemicals in almost every body of water they sampled. Each year since then, at least twenty
studies come out showing these chemicals can affect the hormone systems of wildlife –
and some studies have begun to look at effects on humans. Kinna Ohman reports that,
despite all this, little has been done to address the issue:
Transcript
Less than ten years ago, the U.S. Geological Survey found household drugs and
chemicals in almost every body of water they sampled. Each year since then, at least twenty
studies come out showing these chemicals can affect the hormone systems of wildlife –
and some studies have begun to look at effects on humans. Kinna Ohman reports that,
despite all this, little has been done to address the issue:
Every major water body in the United States, whether it’s a river, lake, or wetland,
probably has at least one scientist keeping an eye on it. Lake Champlain is no exception.
This large lake, forming much of the border between Vermont and northern New York,
has its share of scientists… and Mary Watzin is one of them.
Watzin’s the director of the Rubenstein Ecosystem Science Laboratory in Burlington,
Vermont. She’s been studying how human pollution and activities impact the lake’s fish,
birds, and other water wildlife.
Watzin’s been around long enough to see quite a few of the big pollution problems resolved,
but you can’t help noticing some frustration when she talks about the latest issue:
“We’re cleaning up our act, at least with PCBs – we’re working on mercury – and
then there’s all this new generation stuff coming along.”
This new generation of pollutants includes the active parts of household chemicals and
drugs which have the potential to impact the hormone systems in wildlife. They’re in
detergents, cleaning products, and many types of drugs such as antidepressants, steroids,
and even birth control pills. Chris Hornback is with the National Association of Clean
Water Agencies:
“They’re coming from consumer products. In the case of pharmaceuticals, they’re
coming from drugs that our bodies aren’t completely metabolizing. Or, in some
cases, from unused pharmaceuticals that are being flushed down the toilet.”
And the problem is, once these drugs and chemicals leave our house, many of them aren’t
filtered out at wastewater treatment plants. Treatment plants were not designed to handle
these types of pollutants. So any lake or river which receives treated wastewater can also
receive a daily dose of these active chemicals.
Because these pollutants can number in the hundreds, just how to study them is under
debate. Mary Watzin says the old way just doesn’t work anymore:
“The classic way to examine one of these compounds is just to test it by itself. But
the fish aren’t exposed to these things by themselves, because they swim around in
the general milieu of everything that gets dumped out.”
But looking at how mixtures of household chemicals and drugs affect fish and other
wildlife can bring up more questions than answers. Because of this, Pat Phillips, a
hydrologist with the U.S. Geological Survey says we might want to concentrate on just
keeping these pollutants out of the environment:
“One of the things we see is that we see mixtures of many different compounds
coming into the wastewater treatment plants and coming into the environment.
And its very difficult to figure out what effect these mixtures have. But if we can
remove some of them, that makes a lot of sense.”
In the past, when the issue was industrial toxins, the solution was to control these toxins
at their source. This is because wastewater treatment plants weren’t made to deal with
industrial toxins in the same way they’re not made to deal with household drugs and
chemicals. But now, Chris Hornback says controlling this new generation of pollutants at
their source just isn’t practical:
“A lot of the substances that we’re talking about now including pharmaceuticals
and other emerging contaminants are coming from the households. So, those
sources are much harder to control. You can’t permit a household. A wastewater
treatment plant can’t control what a household discharges so that’s where public
outreach, and education, and pollution prevention efforts come into play.”
These efforts are really only starting. Some states have begun pharmaceutical take-back
programs to keep people from flushing unused medicines down the drain, but
participation is voluntary.
Everyone involved agrees that in order to solve this problem, it’s going to take people
thinking about what they’re sending down their drains. But just how to broach this
somewhat private topic is yet another question.
Triclosan is an active ingredient in many products claiming antibacterial properties. (Photo by Kinna Ohman)
A wastewater treatment plant which is equipped to produce sludge (or biosolids) ready for agricultural use. (Photo by Kinna Ohman)
Sludge will be sent through this press for dewatering and to get it ready for the farmer. This wastewater treatment plant provides Class B biosolids, or sludge for the farmers. Class A biosolids need to go through more complex treatment and screening. (Photo by Kinna Ohman)
After sewage is cleaned at a wastewater treatment plant, sludge is left behind. This
sludge is often used on farms as fertilizer. But the wastewater treatment doesn’t get
rid of all the drugs and chemicals we flush down the drain. Kinna Ohman reports
researchers are finding some of these chemicals are affecting wildlife and could be
getting into our food:
Transcript
After sewage is cleaned at a wastewater treatment plant, sludge is left behind. This
sludge is often used on farms as fertilizer. But the wastewater treatment doesn’t get
rid of all the drugs and chemicals we flush down the drain. Kinna Ohman reports
researchers are finding some of these chemicals are affecting wildlife and could be
getting into our food:
Take a tour of any wastewater treatment plant and you’ll soon understand the main
objective: to separate the liquids from the solids. Until the mid 90s, most of these solids,
or sludge, used to go into landfills or were dumped in the ocean. But in 1994 the U.S.
Environmental Protection Agency started a program to promote the use of sludge on farm
fields as fertilizer. The EPA thought this was the perfect solution… turning waste into a
useful product.
But scientists have found something which could turn the EPA program on its head.
Rolf Halden is an assistant professor at the Johns Hopkins Center for Water
and Health. He says sludge contains most of the chemicals we use:
“If you look at municipal sludge, it really is a matrix that reflects the chemical footprint
of our society.”
Halden’s focused on one chemical he’s found in sludge called Triclosan – and
there’s a lot of it out there. It’s in antibacterial soaps, and can even be in our toothpastes,
deodorants, and shampoos. Until recently, most if it was thought to break down. Now,
Halden says they found something different:
“In the work that we have done at Johns Hopkins, we have demonstrated for example that
Triclosan when it enters a wastewater treatment plant is not effectively being degraded
and half of the mass is left over.”
Halden and his colleagues found this leftover mass in sludge. And since half the sludge
produced each year in the US goes to fertilize farm fields, Halden says we might want to
think about our food supply:
“We really create a pipeline of contaminants that are first discharged into the water and
then accumulated in sludge and then applied in agriculture which opens a pathway for the
contamination of the food supply and the further distribution of these chemicals in the
environment.”
At this point, scientists are still studying levels of this chemical. They haven’t even
begun to understand Triclosan’s effects in agriculture. But there’s something they do
know about it.
Researchers found Triclosan can mimic a thyroid hormone in the North American
bullfrog and disrupt its growth. When its tadpoles were exposed to low levels of
this chemical for a short amount of time, their growth into a juvenile frog was impaired.
But this doesn’t sound like that big of a deal… the frog doesn’t die, it just doesn’t grow
properly, right? Keep in mind that this study tracked exposure to Triclosan over four
hours. Halden says by spreading wastewater sludge in agriculture, we could be exposing
wildlife to chemicals like Triclosan for their entire lives.
“When these chemicals are transported into the environment with the agricultural
fertilizer, which is the municipal sludge, then they sit there for in the soil, not only for
seconds but for days and weeks and for months and to even years and in some situations
in sediments, in aquatic sediments, they can sit there for decades and this implies that
organisms are, for their lifespan, exposed to very high levels of these contaminants.
What the outcome of that is really not fully understood right now and requires more research.”
The U.S. Geological Survey has also been looking for chemicals in sludge – or biosolids –
and they’ve found steroids, antihistamines, and antidepressants. Ed Furlong, a research chemist
with the USGS in Denver, Colorado, says they are now studying how these chemicals react in agricultural
fields:
“We’ve identified that many of the compounds are consistently present in biosolids from
across the country. We’re now trying to understand what happens after those biosolids
are applied to the soil.”
The USGS is not the only agency looking at this issue. The Environmental Protection Agency has been conducting its own survey of chemicals like Triclosan in sludge. They say the results of the survey won’t be released until next
summer. Then comes the complicated process of deciding what to do with the survey
results. A decision about whether to stop using sludge with hormone disrupting
chemicals to fertilize farm fields could be years away.
Some grocery stores are training their staff on the benefits and risks of eating some kinds of fish. Nels Carson (pictured) answers customers' concerns about fish contamination. (Photo by Lester Graham)
Some grocery stores are posting information about fish, but some of the major supermarket chains have done nothing to inform customers about fish contaminants such as mercury. (Photo by Lester Graham)
Fish advisories are confusing. Their guidelines change depending on your gender and age,
and on the type of fish you’re eating. Reporter Kyle Norris boils down
some of the information in advisories and comes up with a few things to think about
when you eat fish:
Transcript
Fish advisories are confusing. Their guidelines change depending on your gender and age,
and on the type of fish you’re eating. Reporter Kyle Norris boils down
some of the information in advisories and comes up with a few things to think about
when you eat fish:
So I did a little informal survey the other day where I asked my friends what they knew about
eating fish. Some of my friends said, “Hey, isn’t eating fish good for you?” Well, turns out they’re right. Fish are
great sources of protein. They’re low in “bad” fats and high in “good” fats, or omega-3
fatty acids, which help your heart stay healthy.
And some of my other friends knew that fish were bad for you. Turns out they’re also right. Fish
take in pollutants through their food and water. Toxins such as mercury, PCBs, and
dioxins. If humans eat enough contaminated fish, those contaminants can build up in our
bodies and cause serious health problems. Contaminants are especially threatening for
small children and women of childbearing age because they can affect children’s
developing nervous systems.
Governments put out advisories so we know which fish are safe to eat. But advisories aren’t
the easiest thing to understand. And anyway, what do you do if you’re in a restaurant, or
cruising through the grocery store and you just want some fish?
“Uh we’re standing in front of the seafood counter at Whole Foods and we’re looking at
our fresh case…”
That’s Nels Carlson. He heads up the seafood department at my local Whole Foods
Market. He says people ask him about fish safety everyday:
“It can be kind of a daunting topic, I think, because there is such a variety. It’s not just a
gross generalization. So it really, it takes a lot of dialogue between customers and team
members and having a very knowledgeable team member base here really helps that.”
They’ll ask him about mercury in the fish, a highly toxic metal that occurs naturally but is a lot more prevalent
mostly because of coal burning power plants. Mercury shows up in higher concentrations
in certain kinds of fish. It’s nice to have a knowledgeable guy like Nels to talk with. Good fish vendors, such as
Whole Foods, go through special training on fish safety. But what if there’s no seafood
expert hanging out next to the fish sticks in the freezer section, if you know what I mean?
Anita Sandretto teaches in the Environmental Health Sciences department at the
University of Michigan’s School of Public Health, and she said that my friends are right.
Okay, well, she didn’t really say that, but she said there are good things about fish and there are bad things about fish:
“If you want to have the benefit of the fat and the omega-3 fatty acids, eat fish with more
fat, but the fat will also be where you will see the contaminants such as PCBs, dioxin.
The flesh will also be where you might have the mercury contamination.”
See, that’s the thing about eating fish: it gets complicated and there are no hard and fast
rules. Sandretto says eating fish is all about treading a line between the advantages and
the risks. So, if there is a risk, you want to reduce it as much as possible:
“…Because if you have any risk in a particular type of food, if you only consume once in
while, you have a less risk of anything bad happening.”
So think in terms of moderation and variety. Sandretto says it’s cool if you want to eat fish once or
twice a week, and to try and vary the kinds of fish that you eat. She says moderation and
variety are actually great rules of thumb to apply to your entire diet. So you could eat a
turkey sandwich on white one day, tuna on whole wheat the next, and a veggie burger the day
after that.
If you eat fish caught from local waters, check with your regional or state health
departments for their fish advisories. Just because a waterway looks clean or is in a
picturesque setting does not mean that its fish are harmless. Contaminants enter the
water in all kinds of ways.
One last thought: imagine a little fish with a little bit of contamination in its body.
Now imagine a medium-sized fish, who swims along and eats that fish and 99 of its closest small
fish friends. That medium guy now has 100 times more contamination than the small fish.
And now let’s say a big fish swims up and gulps down ten medium fish. That big fish has a
concentration that’s 1000 times higher than what that origianal small fish had.
So the moral of that story is, eat smaller fish when possible, also called pan fish. And
at the end of the day, keep in mind that the majority of research, including a recent study
from Harvard’s School of Public Health, say that the benefits of eating fish in moderation
outweigh the risks.
Water contamination from sources that might include some wastewater treatment plants closes some beaches. (Photo by Lester Graham)
Municipal sewer plants are sometimes blamed for high E. coli bacteria counts that close beaches to swimmers. Some cities are working to find better ways to treat the water and put it back into nature. The Great Lakes Radio Consortium’s Chris McCarus reports:
Transcript
Municipal sewer plants are sometimes blamed for high E. coli bacteria counts
that close beaches to swimmers. Some cities are working to find better ways to treat the
water and put it back into nature. The Great Lakes Radio Consortium’s Chris McCarus
reports:
(sound of cars moving along a small street and a few people talking)
A typical summer day by the lake: SUVs pull boats on trailers. People saunter from an
ice cream shop to the city beach. Jet skis and water skiiers slice through the waves.
Carpenters raise trusses on homes being built into the remaining lakefront lots.
Just a few years ago it seemed towns like this were just for loggers and locals. But now
people are flocking to the lakes around the Midwest and staying there. And that’s putting
a strain on local sewer plants.
(sound of machines inside the water treatment plant)
For 40 years, the treated waste water from the Boyne City, Michigan sewer plant has
been released into the big lake it was built on…Lake Charlevoix.
“It’s located right adjacent to a public swimming beach, park, marina and some valuable
waterfront property. We are only a block off the downtown district.”
Plant manager Dan Meads wants to stop mixing the end product with the water where
tourists and the locals swim and play. He tests daily for E. coli bacteria. He
doesn’t want anyone getting sick. But it’s still a concern, and there are other concerns.
In recent years, the United States Geological Survey has reported on new kinds of
contaminants that they’ve found in ground and surface water. The USGS says treated
wastewater from sewer plants can contain hormones from birth control pills, antibiotics,
detergents, fire retardants, and pesticides.
USGS microbiologist Sheridan Haack says the effects of all these compounds are still
unknown. Most are found in tiny quantities, but combined they could cause any number
of chemical reactions.
“There are many different chemical structures and it would be very difficult to state for
all of them what we would actually expect the environmental fate to be and how they
would actually be transported through the environment.”
Haack says the medicines people take don’t disappear. They eventually leave the body
and are flushed down the toilet. Those drugs have been tested for safe human
consumption, but the question is: what happens when those chemicals are mixed in with
industrial waste, accidental spills and nature’s own chemical processes? Haack says they
just might come back around to hurt humans, fish and wildlife.
The Boyne City solution is to build a new wastewater treatment plant two miles from the
beaches up the Boyne River. Officials say contaminants will be diluted by the time they
flow back down into Lake Charlevoix.
(sound of the Boyne River)
Larry Maltby volunteers for a group called “Friends of the Boyne River.” The group
doesn’t like the city’s plan to discharge treated wastewater directly into the river. It wants
them to consider some non-traditional methods. They say the new sewer plant could run
a pipe under a golf course or spray the treated water on farm fields… or let it drain into
wetlands to let nature filter it out.
“It will seep into the soils which are very sandy and gravelly underneath the golf course
and then the filtration through the ground will have a great deal of effect of continuing to
purify that water. Much more so than it would be with a direct deposit, straight into the
surface waters of Michigan.”
Lawyers for the Friends of the Boyne River have appealed to the state dept of
environmental quality and filed a lawsuit.
But wastewater treatment plant manager Dan Meads says the city doesn’t want to please
just one group and end up angering another…
“There isn’t any guarantee that you can satisfy everybody. We think we have the best
option available.”
As municipalities are short on funds and personnel, they don’t want to wait for decades
for the perfect solution. Still, nobody wants any amount of pollution to affect their home
or their recreational area.
Sheridan Haack with the USGS won’t take either side in this dispute. She says not only
are the dangers from contaminants unknown, the best way to deal with them is unknown.
“I am not aware of any consensus in the scientific community on the nature or types of
treatment for this broad range of chemicals.”
In the meantime… communities such as Boyne City have the unenviable task of trying to
dispose of their residents sewage without polluting the beaches, the fishing, and the
environment that brought folks there in the first place.
For the Great Lakes Radio Consortium, I’m Chris McCarus.
When tires are balanced, lead weights are attached to the wheel rim. The weights make sure the tires wear evenly, and ensure a smooth ride. But the Ecology Center says the weights fall off, and the lead degrades easily, posing a risk to human health. (Photo by Mark Brush)
Lead wheel weights are about 95% lead. Two recent studies found that when the weights fall off of cars, they get ground up by traffic. Lead dust is deposited by roadways and sidewalks, and some researchers think the dust might be harmful to human health. The Ecology Center's "Lead-Free Wheels" program is trying to get tire retailers and local governments to switch to non-lead wheel weights. (Photo by Mark Brush)
For years, the government and environmentalists have been working to reduce lead exposure in the environment. Lead can cause developmental damage to children and cause other health problems. The government banned lead in gasoline. It banned lead shot in shotgun shells. There are efforts to get rid of lead sinkers in fishing tackle. And now, environmentalists are trying to ban lead weights used to balance wheels. And some companies and fleet operators seem willing to comply. The Great Lakes Radio Consortium’s Julie Halpert has the story about the move to a less hazardous alternative:
Transcript
For years, the government and environmentalists have been working to reduce lead exposure in the
environment. Lead can cause developmental damage to children and cause other health problems. The
government banned lead in gasoline. It banned lead shot in shotgun shells. There are efforts to get rid of lead
sinkers in fishing tackle. And now, environmentalists are trying to ban lead weights used to balance wheels.
And some companies and fleet operators seem willing to comply. The Great Lakes Radio Consortium’s Julie
Halpert has the story about the move to a less hazardous alternative:
When you buy a new car or get your tires replaced, manufacturers use lead weights, which clip onto the wheel
rim to make sure it’s evenly balanced. They use lead, because it’s heavy, dense. So a small amount by
volume is used.
Still, a few ounces of lead can be used on each wheel. And nearly every car and truck on the road has lead
weights. They’re the second largest use of lead in cars, next to lead acid batteries.
As long as the weights stay on the tires, they’re not a huge problem. But environmentalists are worried that
they come off too often. Many fall off when a car hits a pothole or collides with a curb. Then they’re run
over, ground down and get into the environment.
Each year, roughly 30-million pounds of lead are used to make wheel weights. A recent study estimates that
more than 300 tons of lead fall off vehicles each year in the Midwest alone. Jeff Gearhart is with the Ecology
Center which conducted that study.
“Many people don’t realize there’s a lot of lead in vehicles for this particular use and this is actually a fairly
small percentage of that lead actually falls off. But when you look at it as quantity, it’s pretty significant.”
The weights don’t just pose a problem on the road. Gearhart says there’s also danger when they’re not
properly recycled when new tires are put on and the weights are replaced. Another problem is when a car is
scrapped and then later when the parts are melted down, the lead can be released into the environment.
“Lead wheel weights are not managed very well as vehicles are scrapped and the difficulty in correcting the
management of these at the end of a life in a salvage yard or in a vehicle crusher or a shredder is very
challenging.”
He says the solution is to make sure lead is not used in the first place. Concerned about lead’s potential
health effects, Europe has already decided to ban lead wheel weights starting next year. And Gearhart is
pushing manufacturers who design for the U.S. market to do the same. He says substitute materials, such as
zinc, iron and tin, are readily available and work just as well as lead.
And with funding from the Environmental Protection Agency, the Ecology Center is making lead-free weights
available to those who service vehicle fleets.
(sound of weights being hammered onto wheel rims)
At the city of Ann Arbor, Michigan’s garage, a technician is banging zinc weights onto wheels. Tom
Gibbons helps manage this fleet of 400 city vehicles. Ann Arbor is the first city to switch to lead-free
weights.
“We realize lead is a problem in the environment and in the city, we’re really concerned about the
environment. We’re committed to doing as much as we can to protect it, so if we can take lead out of the
system, why not do it.”
Gibbons says the substitutes work just as well as lead weights. He says once the Ecology Center’s free
supply of weights runs out, the city will began buying non-lead weights, even though they’ll cost slightly
more.
But not everyone agrees with the idea of using other materials for wheel weights. Daimler/Chrysler doesn’t
plan to switch to lead-free weights for its U.S. models. The company is concerned the substitutes are costlier
and more difficult to install on wheels.
Other automakers are looking at eliminating the use of lead weights. Terry Cullum is with General Motors.
He agrees they’re currently an issue, but says the Ecology Center’s estimate of the number of weights that fall
off cars seems high to him. And, he says there’s no imminent danger to the public.
“I think if you look at this from a risk-based situation, we don’t view lead being used in wheel weights
applications as a risk, well, as a large risk, let’s put it that way.”
Even so, General Motors is considering moving to lead free weights. Cullum says that everywhere the
automaker uses lead is a concern. And since the company will have to stop using lead weights on the cars and
trucks it sell in Europe, he says it might be easier just to take them out of all GM vehicles. Still, Cullum says
the substitutes present a big engineering challenge: because they’re not as dense. It takes bigger pieces of
metal to make the same weight. So, they take up more space on the wheel than lead weights.
“It becomes an issue, in terms of where do you put it on the wheel, how do you do it in such a way that it
doesn’t actually interfere with the actual operation of the wheel or the brake systems. That is an issue that is
going through research and engineering right now.”
But Cullum’s optimistic that the issue can be addressed. And other auto makers, such as Honda, are forging
ahead with lead-free weights on at least one of their model.
Still there’s resistance from U.S. tire retailers. The Tire Industry Association says the weights don’t fall off
wheels. And the tire retailers say the lead weights are properly recycled. The group has no plans to stop
using lead weights if they’re not legally required to.
Jeff Gearhart with the Ecology Center says that denial of the problem is a big mistake. He says if
manufacturers and tire retailers cooperated, they could get a substantial amount of lead out of the
environment within a few years.
“There is the potential to make a really significant impact here. We’re talking hundreds of tons of lead
released into the U.S. to the environment that can be eliminated. So we think this is a high priority project,
not just for us, but we think it will be for states and for EPA to look at how to facilitate this transition to
cleaner wheel balancing.”
The Environmental Protection Agency is starting to look at the issue. It plans to conduct a study within the
next year to get a better understanding of the problem and see how lead weights are handled. Then, they’ll
issue guidelines for consumers and tire recyclers late next year. That means the public will be more aware of
the use of lead wheel weights and the potential for toxic exposure. Usually, that means public pressure for
change, whether some automakers and tire retailers like it or not.
For The Great Lakes Radio Consortium, I’m Julie Halpert.
Often our first impulse to clean up a mess is to reach for a chemical cleaner. It’s the same kind of approach in environmental clean-ups. Often the experts first turn to chemicals to clean up badly polluted areas. A new approach to cleaning up pollution has been evolving in recent years. Instead of creating new chemicals to clean up contaminated areas, researchers are trying to use what Mother Nature already provides. The Great Lakes Radio Consortium’s Victoria Fenner has more:
Transcript
Often our first impulse to clean up a problem is to reach for a chemical cleaner. It’s the same kind
of approach in environmental clean-ups. Often the experts first turn to chemicals to clean up
badly polluted areas. A new approach to cleaning up pollution has been evolving in recent years.
Instead of creating new chemicals to clean up contaminated areas, researchers are trying to use
what Mother Nature already provides. The Great Lakes Radio Consortium’s Victoria Fenner has
more:
Nathalie Ross is standing in front of a big water tank divided into three sections. She’s a scientist
at Canada’s National Water Research Institute. She’s working on a different kind of approach
towards environmental cleanup. She explains she’s letting Mother Nature clean up different
aspects of pollution in each section of the tank.
“The first one is what we call natural attenuation, which is based on the natural process to
degrade contaminants, so that’s what we can call our control.”
In the second section, nutrients are added to the water to feed the existing bacteria to see if they
can be stimulated to clean up the water that’s polluted with chlorinated products.
“The third tank, in addition to the nutrients, we add bacteria. And those bacteria were shown to
degrade the chlorinated products, so we are hoping that it would speed up and also complete the
process to the end where we are hoping to see no contaminant at all.”
What Ross is demonstrating is “Green Chemistry.” Also known as Green Technology, the
concept is simple – instead of creating brand new chemicals, it’s becoming increasingly possible
to use the chemicals and processes already available in nature. The thought is that naturally
occurring compounds will be less harmful than the ones that we invent in the lab.
There are two streams of green chemistry – one is using environmentally conscious principles in
the production of new products and processes – water based paints and fuel produced from corn
are a couple of examples. Nathalie Ross is demonstrating the other stream – using naturally
occurring substances and biological agents such as bacteria to clean up the pollution we’ve already
created.
Jim Nicell is doing similar work. He’s an associate professor in the Department of Civil
Engineering at McGill University in Montreal. He’s working with enzymes that will clean up
toxic waste. He’s found a surprisingly ordinary source of the enzymes – a piece of horseradish
root.
“You can take your horseradish, put it in a blender, get the horseradish sauce if you want and
have it for supper. But before you do that, squeeze out the juice which is pretty awful, raw,
smelly stuff, which actually has a high concentration of this enzyme. I literally took that juice
and added some hydrogen peroxide and into a solution that contained some pretty toxic materials
and they just precipitate out. And so with a very small quantity of this enzyme we can actually
have a major impact on reducing the toxicity of that waste.”
The simplicity of Green Chemistry has been gradually attracting the attention of scientists and industry over
the past fifteen years. In terms of scientific developments, it’s still pretty young. But it’s a
concept that makes a lot of sense to Nicell.
“Nature is a whole lot smarter than we are. It’s had a lot more time than we’ve had to optimize
the way things are carried out. Now, we have a whole bunch of industrial catalysts that we have
made in the past but we don’t have nearly the time or, I guess, the capability, the experimental
setup that nature has had to produce the optimal catalysts.”
It might seem like an ideal solution, but critics say we need to be careful. One of the concerns
which has been raised is ecological balance – whenever large quantities of any substance are
released, even natural ones, there is often a risk that we’ll change the environment in ways we
don’t want to.
Brian McCarry is a scientist with the Department of Chemistry at McMaster University in
Hamilton, Ontario. He says, despite that concern, we shouldn’t be overly worried.
“They’re natural organisms, they’re not pathogenic. I don’t think they’re going to disrupt the
balance of nature. They’re not like putting in some really vigorous organism that takes over.
These are also not mutant, genetically engineered organisms so I don’t think anybody should be
terribly worried about having all sorts of strange genetic material floating around that are now
going to get into the ecosystem and run amok.”
There’s one other big concern about Green Chemistry: the cost. Both Nathalie Ross’s water
project and Jim Nicell’s horseradish experiments are still in the early stages. It’s not clear yet
whether it will be cost effective for large-scale industrial applications. But given the benefits of
green chemistry, advocates hope that the value of using the simple answers nature offers will also
be considered, not just the cost.
For the Great Lakes Radio Consortium, I’m Victoria Fenner.
Columbia University professors say they have found the first evidence that two banned pesticides are harmful to humans. They say their study vindicates a decision by the Environmental Protection Agency to phase out the chemicals based only on preliminary research on animals. The Great Lakes Radio Consortium’s Tracy Samilton reports:
Transcript
Columbia University professors say they have found the first evidence that two banned pesticides
are harmful to humans. They say their study vindicates a decision by the Environmental
Protection Agency to phase out the chemicals based only on preliminary research on animals.
The Great Lakes Radio Consortium’s Tracy Samilton reports:
Chlorpyrifos and diazinon were once found in over-the-counter products for
in-home pest control. The EPA started to phase out the chemicals four
years ago, after preliminary research showed the chemicals could be
harmful. The new study tracked a group of pregnant women in New York
before, during and after the ban. It found that women with the highest
concentration of the pesticides in their blood had smaller and shorter
babies than those with less exposure. Robin Whyatt is with Columbia’s
Mailman School of Public Health. She led the study. She says there’s no
question the research vindicates the EPA’s decision.
“It certainly supports that that was a good regulatory decision and this also shows that regulation
works.”
While Whyatt says the ban was good policy, she says more studies should be
done to confirm her results. Chlorpyrifos and diazinon are still widely
used in agriculture. Some environmental groups say the chemicals should
also be phased out there.
For the Great Lakes Radio Consortium, I’m Tracy Samilton.
The Clean Air Act says gasoline must contain additives to help it burn more cleanly. But the common additive MTBE is a proven environmental threat. And a new study says the alternatives could be just as dangerous. The Great Lakes Radio Consortium’s Corbin Sullivan reports:
Transcript
The Clean Air Act says gasoline must contain additives to help it burn more cleanly. But the
common additive MTBE is a proven environmental threat. And a new study says the alternatives
could be just as dangerous. The Great Lakes Radio Consortium’s Corbin Sullivan reports:
Underground storage tanks at gas stations can leak. Fuel
additives like MTBE leak faster than the gas and can
cause groundwater pollution.
For that reason, seventeen states, including New York,
Michigan and Illinois have restricted or will restrict the use
of MTBE in gasoline.
That means other fuel additives intended to reduce air
pollution will have to be used instead.
Mel Suffet co-authored a new study published in the
journal Environmental Science and Technology.
He says some of the alternatives to MTBE can cause the
same problems.
They can be toxic and can make groundwater
undrinkable. Suffet says to solve the problem, leaks need
to be prevented.
“The first thing you have to do is develop a design of
underground fuel storage tanks to emphasize containment
leak detection and repair.”
Suffet says even modern tanks are prone to leaks. So he
says designers need to go back to the drawing board to
create a leak free tank.
For the Great Lakes Radio Consortium, I’m Corbin
Sullivan.
2.6 billion pounds of arsenic and other toxic pollutants flooded over nearby farmland and into the river. (Photo courtesy of the Tennessee Department Of Health)
