During the textile manufacturing process, excess dyes are sometimes discharged as wastewater resulting in water pollution downstream. In recent years, particular attention has focused on water pollution in China resulting from indigo dyes used to create the distinctive blue color of denim blue jeans.
Some nanoscientists are looking at ways to help remove potentially harmful dyes chemicals from water.
Scientists at Colombia’s Universidad Industrial de Santander and Cornell University have come up with a cheap and simple process using natural fibers embedded with nano particles to quickly remove dye from water.
The research takes advantage of nano-sized cavities found in cellulose; plant fibers can be immersed in a solution of sodium permanganate and then treated with ultrasound causing manganese oxide molecules grow in the tiny cellulose cavities. The treated fibers are able to quickly break down and remove the dye from the water.
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Courtesy Mark RyanOver the past couple years, Science Buzz has posted several stories (here and here) about the humongous patches of garbage and plastic debris found floating in the world's oceans. It's a serious problem and one that should raise red flags for anyone concerned with the Earth's environment. But even more troubling is the recent news that plastic particles have now been found in all five of the Great Lakes lining the border of the USA and Canada. Unlike the large globs of plastic clogging areas of the ocean, the plastics polluting the Great Lakes are microscopic particles detectable only in a microscope. But they're no less disturbing.
A team of researchers led by Dr. Sherri “Sam” Mason, professor of chemistry at SUNY-Fredonia has been gathering water samples and reported finding high concentrations of plastic particles in the chain of freshwater lakes. One of the researchers involved is environmental chemist Lorena Rios-Mendoza from University of Wisconsin-Superior. Both she and Mason have studied the Great Trash Island (aka Trashlantis) in the Pacific Ocean but has now turned their attention to the Great Lakes.
Most of the plastic found in the water is visible only under a microscope, but has been found in all five of the Great Lakes, both in the water column, and in lake sediment. The amount of micro-plastic varies between lakes with Lake Erie - the shallowest and smallest by water volume - containing the largest ratio and Lake Superior - the largest and most voluminous - a much smaller ratio. But it doesn't matter; the point is that we're polluting some of our important sources of fresh water with plastic.
It's thought that cosmetics with could one of the sources, since the industry relies heavily on using micro-beads in its products. These tiny plastic particles used on our faces, skin, and teeth, eventually get washed off into the water supply where they're too small to get filtered out. But cosmetics certainly aren't the only source.
Courtesy tedxgp2Think of the ungodly amount of plastic material we use and discard every year. Surprisingly, only about five percent of the bags, bottles, cups, electronics, etc. get recycled; most plastic trash ends up in landfills where it slowly degrades and eventually finds its way into the world's favorite garbage dump: the oceans.
“We have no idea how long some of these plastics stay in the ocean, could be more than 40 years,” Rios-Mendoza said. She also worries if organic toxins in the water can attach themselves to the tiny plastic particles, and end up in the food chain. In this regard, Rios-Mendoza has been sampling Great Lake fish to see if such toxic particles are present in their guts.
It's important to remember that only 3 percent of the world's water is freshwater and the five Great Lakes - Superior, Huron, Michigan, Ontario, and Erie - together contain 20 percent of that freshwater. That's a large portion of a relatively scarce and essential life ingredient. Last fall, I posted an interesting graphic that illustrates nicely Earth's total water supply versus fresh water and puts things in perspective.
Courtesy Mark RyanRios-Mendoza and Mason have been collaborating with a research and education group called 5Gyres Institute that monitors and studies garbage patches found in five subtropical gyres in the world's oceans. Rio-Mendoza presented a preliminary study of their work on the Great Lakes at a recent meeting of the American Chemical Society. The team's future studies involve pinpointing the sources of plastic pollution and acquiring a better understanding of how plastics degrade in the environment.
"We all need to become aware of how much plastic we use in our lives and avoid using single-use products. Don’t buy water in plastic bottles or cosmetic products with micro beads. Bring re-usable bags to the store with you. Simple things like this make a big difference, but it’s also important to keep talking about this issue and raising awareness about how it affects the Great Lakes and the world’s oceans.” --- Dr. Sherri Mason“
By the way, here in Minnesota, and situated at the western tip of Lake Superior, the city of Duluth was recently proclaimed to have the best tasting drinking water in the state. By best-tasting, I'm assuming they mean it has no taste whatsoever since water is described as a colorless, tasteless liquid. Whatever the case, I always thought Duluth's drinking water was the best while growing up there (my grandparents lived in a Twin Cities' suburb and I never liked the taste of their softener-treated water).
In another water-related story, it's estimated that life on Earth can survive for at least another 1.75 billion years until we move out of the habitable zone and our oceans (and other water sources) will evaporate in the increased heat. So it's probably best that we take care of what water we have - it needs to sustain us for a long time.
Courtesy NASA/JPL-Caltech/MSSSAfter last week's disappointing news that no signs of current life have been found living on Mars, NASA scientists have just confirmed some pretty exciting news: the Mars rover, Curiosity, has found water on the Red Planet. Analysis of dirt and fine soil scooped up from the Rocknest site on the surface of Mars has revealed that it contains water. This is big news. Read here what NASA has to say about it.
Courtesy Welome ImagesResearchers from the University of Amsterdam have found that nanomachines work more efficiently when water is added as a "lubricant". Nanomachines are structures just one molecule in size (a few dozen atoms or so) that do work. When researchers added a small amount of water to the solvent that surrounded the nanomachines, the machines moved much faster.
Discovering how to optimize these tiny machines is important for the development of things like molecular computers and surfaces that can change properties.
Courtesy US Geological SurveyThis cool graphic from the USGS Water Science School website gives you a really good idea of just how much water there is on Earth. Compared to the Earth itself, it doesn't look like much. The large blue globe represents the volume of all the water present on Earth, i.e. in the oceans, lakes, icecaps, atmosphere etc. The next size is the volume of the all fresh water - much of which is located underground. Don't overlook the very tiny blue globe positioned beneath the mid-sized water globe and just northwest of Florida in the graphic. That's how much fresh water is contained in all the lakes and rivers on Earth - the sources of life's drinking water. Feeling thirsty now?
Courtesy Tomas CastelazoIt was just a few weeks ago we posted incredible pictures and video of devastating floods ripping through Duluth. Now, on a national scale, the weather story is drought. But how bad is it really?
Depends on where you live, but much of the Midwest is falling into drought conditions. It's bad, but not as wide spread as the peak of U.S. drought conditions from 1934. USA Today has an interesting toggle map that allows you compare today's conditions with that record drought.
Even earlier this summer, heavy rains in the Twin Cities had lockmasters along the Mississippi River shutting their gates to control fast-flowing river water. Now downstream, the Mississippi is approaching record-level lows. In some areas around Memphis, the river level has fallen 55 feet from highs set last summer. This CNN website report has interesting satellite images of the newly slimmed Mississippi compared to last year's look.
What do you think of this crazy weather? Share your thoughts here with other Buzz readers.
I've been checking out some of the visual material taken of yesterday's massive flooding in Duluth and thought this one was pretty interesting. The video of the raging Miller Creek in Lincoln Park was taken while it was still raining and you see can visible change in the water level by the end of it.
Courtesy Mark RynThe recent floods in Duluth and other communities in northern Minnesota illustrate the incredible erosive power of running water. I was living in Duluth in 1972 when floods then ripped up the entire length of 6th Avenue East from top to bottom. This go-round appears to be even more devastating. I was particularly saddened to hear that the Swinging Bridge at Jay Cooke State Park has been destroyed by the force of the St. Louis River. The Lake Superior Zoo was inundated with water killing several of animals there. Several animals escaped, including the polar bear which was quickly tranquilized, recaptured, and sent to Como Zoo in St. Paul. One seal was more successful in its escape and made it out of the zoo compound to Grand Avenue where it stopped traffic. Recovery from all the damage is going take a while.
About a month ago, a frack-sand mining operation near Grantsburg, WI, spilled some fine-grained sediment from a settling pond into a tributary of the St. Croix River. Local news media covered the story, and more details, for example, can be found in the Pioneer Press story by Dennis Lien.
So what’s the big deal?
Well, there are standards regarding water turbidity, which means that as a society we’ve decided that we don’t like cloudy water, at least in some settings and at some levels. For a naturally clear-water system like the St. Croix, increasing turbidity would alter the food chain at all levels. Algal primary producers rely on sunlight blocked by turbidity. Sight-based predation at the top of the food change would be altered. Benthic (bottom-dwelling) organisms that depend on coarse substrates could be smothered by siltation. Especially in the St. Croix, one of the last refugia for freshwater endangered mussel species, we must be on guard against too much fine sediment. And finally, where does the sediment end up? It’s filling up not only man-made reservoirs but also treasured natural lakes, iconically Lake St. Croix and Lake Pepin. These lakes are filling in with fine-grained sediment at about 3X and 10X their natural rates, respectively. (How do we know? See work done by the Museum’s St. Croix Watershed Research Station.)
Hey, it’s only a little bit...
Or was it? How much is a little? A little here, a little there, and a little more from over there -- it starts to add up. All water in a watershed runs downhill to the river, efficiently carrying both particles and dissolved materials. The river ultimately sees it all: all the disturbances, however seemingly minor, throughout the watershed. Rivers die a death of a thousand cuts. We have enough difficulty trying to control nonpoint sources of sediment and other pollutants. Stopping discharge of fine-grained materials from a mining operation is eminently fixable. It’s the right thing to do. Fortunately, all parties seem in agreement on this, including the mining company, which has repaired its leaky dike.
"The New York Department of Environmental Protection installed a prototype "algal turf scrubber" at once of its wastewater treatment plants in Queens. The scrubber--two 350-foot metal ramps coated with algae that grows naturally--is designed to use algae to remove nutrients and boost dissolved oxygen in the water that passes through it. John McLaughlin, Director of Ecological Services for the New York City Department of Environmental Protection (DEP), and Peter May, restoration ecologist for Biohabitats, explain how the scrubber works, and where the harvested algae goes."