New EPA rules label a dozen more Collier, Lee waterways as polluted

More Southwest Florida streams and canals would violate water quality standards under a proposal by the U.S. Environmental Protection Agency to limit pollution in Florida waters, according to a Naples Daily News analysis.The EPA is proposing to set specific numeric limits for nutrient pollution, replacing Florida's more general standard that requires only that nutrients not upset the natural balance of a waterway.Nutrients, such as nitrogen and phosphorus, end up in Florida waters from urban and farm runoff, triggering ugly algae blooms that can poison water supplies, kill fish and smother marine life.A dozen Collier and Lee county streams and canals considered not polluted under current state rules would be considered polluted under the EPA proposal, the analysis shows.They include the L-28 tieback canal on the eastern edge of the Big Cypress National Preserve, the Tamiami Trail canal, the Faka Union canal, Camp Keais south of Immokalee, canals that drain into Rookery Bay National Estuarine Research Reserve and the Golden Gate canal that drains into Naples Bay.In Lee County, the newly designated polluted water bodies would include the eastern Caloosahatchee River above the Franklin locks and Palm Creek as well as Bayshore Creek/Chapel Creek, which drain into the Caloosahatchee.Some water bodies — the Estero Bay drainage area and the Ten Mile canal in southern Lee County — would be dropped from the polluted waters list under the EPA proposal, the analysis shows.The Daily News analysis compared the DEP's current lists of polluted waters with a database created by the DEP, applying the EPA's proposal to water bodies around the state.A spot on the list of polluted waters triggers cleanup requirements under the federal Clean Water Act.The EPA proposal is an outgrowth of a settlement of a lawsuit that environmental groups filed in 2008 after Florida missed a 2004 deadline to shore up the state's water quality standards.Agribusiness groups and utilities have objected to the EPA proposal, saying it will be too costly and questioning the science behind it.Collier County commissioners are set to decide in the coming week whether to formally object to the EPA proposal."This seems to be the sledgehammer instead of a little mallet approach," said Jerry Kurtz, the county's principal stormwater project manager.He said the county hasn't estimated how much it might cost to comply with the EPA proposal — or even whether it would be possible."We can't get our arms around it at all," Kurtz said.The longer list of polluted waters shows that the state's current standards aren't doing the job, said Earthjustice attorney David Guest, who represented environmental groups in the 2008 lawsuit."When you have numeric standards, you learn things you didn't know before," he said.The state's current standard is akin to waiting for a fish kill or a toxic slime outbreak to determine a water body is polluted, Guest said."That's too late," he said.Guest accused the DEP of using the database as "scare literature" to whip up opposition to the EPA's proposal on the grounds that it will cost too much to clean up all the newly designated water bodies.The DEP database is meant to try to determine whether the EPA proposal is properly assessing water quality in the state's streams, lakes and canals, said Julie Espy, environmental administrator in the DEP's watershed assessment section."If a canal seems to have good water quality to you and it fails (the EPA criteria), you might wonder why is that," she said.Naples News

Robotic fish a step forward for zoologists

ast Lansing, MI - Unless it's a pseudo-fish named NEMO (Navigating EAP-Controlled Module with Onboard Resources) - designed to monitor water temperature, oxygen levels, invasive populations and pollutants.

For example, a robofish will be able to navigate independently and transmit information about the location of toxic algae blooms.

"We chose to fit these fish with sensors for toxic algae blooms, but I think other researchers will use this technology in the future to monitor different aspects of water quality," Michigan State University zoology professor Elena Litchman said.

According to Litchman, excess nutrients and warmer temperatures create an ideal growth environment for algae, which release toxins that are dangerous to other aquatic organisms and humans.

"Although it's hard to remove these blooms, knowing where they are allows us to warn people not to go in those areas," Litchman said. "We can remove them by aerating the water, but that uses electricity, which increases global warming."

By giving researchers and scientists an accurate picture of what's going on underwater, the robofish will aid in the early identification of problems like an expanding invasive species population or other causes of declining native species.

"At first it was like science fiction, but now I think it's going to be a reality," Litchman said.

According to chief developer Xiaobo Tan, assistant professor of electrical and computer engineering at MSU, the robots won't disturb their aquatic neighbors with loud electrical motors or awkward or jerking movements. They'll be able to maneuver themselves in the water like real fish.

The polymer material Tan used in the prototype operates on electricity, activating fins that function like muscle fibers. The fins, which are powered by an internal lithium battery, move either when the remote control tells them to or, much like biofeedback, when the robot's sensors and GPS indicate there is a reason to move.

Tan said he believes this technology should be affordable enough that it will have multiple applications. He said he's designing the robofish to cost less than $1,000 per fish, but he doesn't know when it will go into full production.

The project, funded by the National Science Foundation, cost about $410,000, Tan said. The background research for the project was another half-million dollars.

First Successful Use Of New Ocean Observation Technology – Investigation Of Ocean Acidification In The Baltic Sea

For the first time scientists and technicians from the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany, successfully used an offshore observing system to study environmental changes in the oceans.

The so-called mesocosms resemble oversized test tubes with a length of 20 metres. They are used to simulate the future ocean in situ, i.e. under realistic conditions. IFM-GEOMAR scientists used six of these mesocosms, each encompassing about 60,000 litres of sea water, at the observing station Booknis Eck in the Baltic Sea in order to study the effects of ocean acidification.
Above the sea surface they seem unimpressive: six vertical orange sticks connected by a transparent plastic roof. The dimension of these devices which were installed at Booknis Eck in the western Baltic Sea is revealed under water. A 20 metre long, flexible plastic tube is affixed on a rack that serves for buoyancy and stability of the system. In this tube scientists can isolate about 60 cube metres of seawater under natural conditions in terms of temperature, stratification and ecosystem.
“So far we had studied the impact of changes such as the increase of fertilizers or of the carbon dioxide concentrations in small tanks in the laboratory. The new mesocosms enable us to study the developments under natural and controlled conditions Thus, we can better estimate their impact on the ecosystem,” states project leader Prof. Ulf Riebesell from IFM-GEOMAR.
The first mission of the mesocosms, a technology developed at IFM-GEOMAR, was dedicated to research on the impact of ocean acidification. “The ocean absorbs more than a third of the carbon dioxide produced by human beings. As a consequence the pH-value decreases and the ocean acidificates,” says Prof. Riebesell. Many marine scientists regard this process as equally dangerous as the ocean warming. “Now we want to know how the impact of the acidification on the marine ecosystem looks like,” Riebesell explains. A final assessment of the experiments at Booknis Eck cannot be given yet. But according to Riebesell the experiments were very successful since a large amount of data was generated.
The study was conducted together with partners of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, the Leibniz Institute for Baltic Sea Research in Warnemünde, the Leibniz Institute of Freshwater Ecology and Inland Fisheries in Berlin and 19 students from Kiel. It is part of the joint project SOPRAN (Surface Ocean Processes in the Anthropocene) funded by the Federal Ministry of Education and Research that has also part-financed the development of the worldwide unique mesocosm systems. International parties from the USA and the UK have already expressed interest in the new technology.
The experiment in the Baltic Sea was a test for a large-scale project which will take place off the coast of Svalbard in spring 2010 under the leadership of IFM-GEOMAR with contributions of 15 other European partners in the context of the European project EPOCA (European Project on Ocean Acidification). The main focus will be again the ocean acidification.
A decision on proposals seeking for funding of additional mesocosm experiments in the context of SOPRAN is expected soon.
Adapted from materials provided by Leibniz Institute of Marine Sciences (IFM-GEOMAR), via AlphaGalileo.

Voyage to the centre of the 'Plastic Vortex'

A group of conservationists and scientists is due to set sail for an obscure corner of the Pacific Ocean in the coming months to explore a vast swirl of waste known as the "Plastic Vortex."The giant gloop -- which some scientists estimate is twice the size of Texas -- has been gradually building over the last 60 years as Asia and the United States tossed their unwanted goods into the ocean.Everything from flip-flops to plastic bags have been slowly broken down by the sun's rays into small particles, and ocean tides have meant much of it has settled in a spiralling pattern just below the ocean surface between Hawaii and the mainland United States.After only coming to scientific attention in recent years, little remains known about the vortex, also known as the "Eastern Garbage Patch," so the expedition hopes to find out if the plastic can be fished out of the sea -- and what can be done with it.Jim Dufour, a senior engineer at Scripps Institution of Oceanography in California, who is advising the trip, said establishing the extent of the problem was vital for the future health of the oceans."Importance is an understatement, it's imperative. It will take many years to understand and fix the problem," he told AFP.The United Nations Environment Programme says around 13,000 pieces of plastic litter are found in every square kilometre of sea, but the problem is worst in five ocean gyres, or spiralling ocean currents, the worst of which is in the North Pacific.The plastic has become so small most of it cannot be seen by satellite pictures, but the volume means the poisonous soup is being unknowingly vacuumed up by marine life and birds, and much of it is heavy with toxic chemicals, organisers of the trip say."That means the little piece of plastic the fish eats is actually a little toxic bomb," said Doug Woodring, an entrepreneur and conservationist who lives in Hong Kong and will lead the expedition.As a result, a lot of the toxins could be getting into the human food chain.Woodring said the location of the swirl -- more than 500 nautical miles from the west coast of the United States -- meant it remains a mystery for scientists."It is like going to outer space," he told AFP.The 50-day voyage will head from San Francisco to Hawaii and back, passing through the vortex twice.It will be led by a 150-foot-tall (45-metre-tall) ship, the "Kaisei" -- which means Ocean Planet in Japanese. Accompanying will be a fishing trawler, which will be trying out techniques to catch the waste without destroying too much marine life."You have to have netting that is small enough to catch a lot but big enough to let plankton go through it," said Woodring.Ocean scientists and a documentary crew will be on the trip, which also hopes to examine whether the waste can be recycled or even used to create fuel.The mission -- which is still looking for funding to meet its two million US dollar budget -- has received the backing of the United Nations Environment Programme and sponsorship from water company Brita.But the swirl's location in international waters meant it was difficult to get any government support to clean it up."There is no jurisdiction, no government who is entirely responsible, so there has been no push to clean it up. The world doesn't know it is out there," said Woodring.Several other trips have either made or planned journeys to the vortex, but Dufour says this will be the most scientific-focused venture."It will be the first scientific endeavour studying sea surface pollutants, impact to organisms at intermediate depths, bottom sediments, and the impacts to organisms caused by the leaching of chemical constituents in discarded plastic," he said.But for everyone involved in the project, the phenomenon only highlights the wider issue of reducing waste."The real fix is back on land. We need to provide the means, globally, to care for our disposable waste," said Dufour. By Guy Newey, AFP

Death From Above for Plankton

Nutrient-rich particles sifting out of the atmosphere can be a boon for phytoplankton, the tiny floating algae that support ocean food webs. But new research suggests that some particles are poisoning phytoplankton, potentially disrupting marine ecosystems and altering the amount of greenhouse gases withdrawn from the atmosphere.These atmospheric particles, or aerosols, can be natural or humanmade and include mineral-rich dust, soot, organic molecules, and sea salt crystals. Previous studies have emphasized the benefits of aerosol deposition in the ocean. This delivers high concentrations of phosphate, nitrogen, and iron that stimulate growth of phytoplankton. But aerosols don't contain only nutrients. They're a dry cocktail of substances that also include pollutants responsible for acid rain. Until now, scientists have overlooked their potential harm to the ocean. Oceanographer Adina Paytan of the University of California, Santa Cruz, and colleagues wanted to get a wider view of aerosols' effects on ocean productivity, so they decided to determine how several components of aerosols, not just the nutrients, affected phytoplankton communities in the Red Sea. The team collected aerosols blowing in from Europe and Africa and mixed them with water samples from the Red Sea. Phytoplankton exposed to the European samples thrived, but the ones mixed with the African aerosols took a nose-dive. The researchers noticed that the aerosols derived from Africa had nearly three times as much copper as the European samples. Further experiments confirmed that the copper levels in African aerosols are lethal to two groups of phytoplankton, as the team reports online this week in the Proceedings of the National Academy of Sciences. To get a global view of the possible impact, Paytan and her team modeled the amount of copper deposition in the oceans. They identified two hot spots for human-induced copper deposition: the Bay of Bengal just east of India, and areas in the Pacific Ocean near southeast Asia and China. Paytan says that phytoplankton in these areas may be more sensitive to the toxic element because they probably aren't accustomed to the current levels, which are globally 50% higher than before the industrial revolution. "This is a useful heads-up to a potential new problem," says marine and atmospheric chemist Alex Baker of the University of East Anglia in the U.K. Bill Landing, an oceanographer at Florida State University in Tallahassee, says that although extrapolating their findings to the world's oceans may be a bit premature, the study is a good first step. "They do a good job of pointing out the potential impacts, and most of them aren't good," he says.

Watershed meeting will seek solution to pollution

The Lemon Bay watershed is under siege. But, Sarasota County officials said, it doesn't have to stay that way. And that will be the goal of an interactive workshop, open to the public and aimed at discussing ways to protect and preserve the quality of the area's creeks and bays. The meeting will be held at 9:30 a.m. to 11:30 a.m. March 21 at the Englewood Sports Complex, 1300 River Road. Sarasota County staff members will lead a discussion with residents about ways they can continue to work together to maintain and improve sea life habitat and water quality in this particular watershed. The watershed workshop is a cooperative effort of Sarasota County and the Southwest Florida Water Management District. The workshop will open with a discussion of the land and water bodies that comprise the Sarasota County portion of the Lemon Bay watershed. The watershed drains into northern Lemon Bay and consists of Alligator Creek, Woodmere Creek, Forked Creek, Gottfried Creek, Ainger Creek and Manasota Key. Project manager Michael Jones said urban development has brought major changes to the watershed over the past half century. "Natural areas were converted to residential, commercial, agricultural and public use," Jones said. "Area residents, builders and developers certainly didn't set out to threaten sea life or water quality." However, he added, "more people and development have placed greater stress on all our natural systems, including the Lemon Bay watershed." Jones said many of the pollution problems in the watershed can be traced to the fact that without the benefit of natural filtration, rainfall streams directly into the bay. That means it is carrying with it pollutants from stormwater runoff. The good news, he said, is that there are opportunities to protect natural systems throughout the watershed through stormwater and landscaping guidelines. "Low-impact design manages rainfall by capturing it on-site," he said. "This approach closely mimics nature by helping to control downstream flooding, reducing water pollution and the imbalance of fresh and saltwater in the estuaries." Sarasota County's landscape and fertilizer management ordinances prescribe appropriate plant materials, as well as fertilizer type and application schedules, he said. For more information about the workshop, call 941-861-5000.

Cleanup Method Uses Activated Carbons To Anchor Toxins To Bottom Of The Bay

Imagine a Brita filter big enough to clean up San Francisco Bay। Richard Luthy, chair of Stanford's Department of Civil and Environmental Engineering, has a plan to clean polluted sediment at Hunters Point in San Francisco with activated carbon—the same technology in many water filters. Luthy proposes to sequester dangerous toxins by mixing activated carbon, a type of carbon with a large surface area, into the bay's contaminated sediment.

Luthy, the Silas H. Palmer Professor of Civil Engineering, has discovered that certain toxins in mud stick so well to activated carbon that they are rendered much less harmful—like flies stuck to a fly strip. Luthy and his team want to apply this technique to contaminated waterways. They recommended their technique to the U.S. Navy, which is responsible for the cleanup at Hunters Point.
"This technique is radical because we are changing the chemistry of the sediment rather than digging up the mud and hauling it away," Luthy said.
There are a lot of toxins in the bay, but Luthy's work concerns PCBs, polychlorinated biphenyls. PCB is a long-lived industrial chemical and probable carcinogen. It has been banned since 1979, but the PCBs already in the environment show no signs of leaving. "Bacteria don't destroy them, and humans don't have an easy way to deal with them in our bodies," Luthy said.
The PCBs at Hunters Point, San Francisco's only Superfund site, oozed into the bay from contaminated soil in the nearby naval shipyard landfill. Although erosion from the landfill deposited PCBs into the bay, they don't mix well with water and instead attach themselves to the sediment on the mud flats. Since this land was leased to many different companies after the Navy ceased active operations there in 1974, it is impossible to point the finger of blame at one party, Luthy said. The Navy built a retaining wall around the landfill and recently excavated it, so no further PCBs can leak into the bay from this site
Like mercury, PCBs get into our bodies through fish. Small marine creatures, such as worms and clams, eat contaminated sediment and accumulate PCBs in their fatty tissues. When fish eat the clams and worms, the toxins concentrate even further in fish fat. So by the time the PCBs get to us, at the top the food chain, they are highly concentrated.
The land at Hunters Point will eventually be transferred to the city of San Francisco, but a 2002 bill requires it to be cleaned up first. At its current contamination levels, it is not safe for the city's planned use, which includes a new stadium for the San Francisco 49ers. Dredging, or scooping up, the contaminated sediment and dumping it elsewhere is currently a favored method for dealing with sediment contamination, but, as Luthy and other scientists wrote in a National Research Council committee statement released this July, it does not always work.
The dredge usually cannot get every inch of the sediment. And leaving behind just a small amount of contaminated sediment could actually make matters worse, Luthy said. The bottom few inches of sediment are sometimes more contaminated than what is taken away, since the lower, older layers of sediment could date back to days when PCBs were still in widespread use. Because the worms and clams live only in the top layer, organisms in that body of water could ultimately end up with higher levels of PCBs in their systems.
Even when dredging does work, "it's like a shell game; you have to put the contaminated sediment somewhere," Luthy said. "We have to learn how to solve our environmental problems where they are, and not ship the problems off somewhere else."
Luthy found that PCBs stick most readily to carbon particles naturally present in the aquatic environment and thought he might enhance this natural process by giving PCBs extra carbon to stick to. Luthy and his team members tested this theory in the lab by mixing soil from various polluted sites around the country, including Hunters Point, with activated carbon, a kind of porous carbon with extra surface area for the molecules of PCB to stick to.
They found that a clam left in a mixture of contaminated sediment and activated carbon for a month absorbed one-tenth the amount of PCBs in its fatty tissues as a clam that sat in contaminated soil with no carbon. The researchers then marked PCBs with radioactive labels and mixed them with activated carbon. When they fed this radioactive mixture to the clam, they saw that 98 percent of the radioactivity passed right through it; the PCBs were so tightly bound to the carbon that they could no longer enter the food chain.
The Department of Defense funded a study for Luthy to move his technique from the lab to the bay. In one test, Luthy and his team members dumped more than 1,100 pounds of activated carbon onto about 400 square feet of the muddy flats in South Basin, an inlet just south of the naval shipyard. They mixed the carbon into the bay's sediment using an Aquamog, a machine normally used as a big weed whacker for marine vegetation, which Luthy described as a giant rototiller attached to a barge. Luthy's team tested the water to make sure they were not kicking up extra PCB contamination with their mixing, a step Luthy said is an important part of the field test for any contaminated locale.
Seven months later, after the carbon and PCBs had had plenty of time to find each other, they put mesh cages containing clams in the mud-carbon mixture. After another month, they saw 50 percent less PCBs in these clams compared with clams left in untreated dirt. So Luthy felt confident recommending his technique to the Navy: "It's not some wacko idea of a professor," he said. "You could get real environmental contractors out there doing this."
Luthy does not think adding extra carbon to our waterways will significantly affect the local environment—field tests here have shown no major changes in the local organisms six months after carbon addition, and more tests are being done 18 months after mixing. However, Luthy is worried that the recent oil spill in the San Francisco Bay may have diminished the pool of healthy organisms that could repopulate Hunters Point once it is cleaned up.
It is hard to know how well this technique will translate into healthier fish, because fish will not stay put like clams and could be eating contaminated organisms from other waterways, Luthy said. But he sees smaller organisms, such as clams and worms, serving as the canaries in the coal mine for our bay: If their toxin levels go down, those of fish and humans will eventually follow suit.
Additional funding for Luthy's studies was provided by Stanford's Bio-X program, Schlumberger and Alcoa.
Adapted from materials provided by Stanford University.

Pollution from marine vessels linked to heart and lung disease

Pollution from marine shipping causes approximately 60,000 premature cardiopulmonary and lung cancer deaths around the world each year, according to a new report। The report benchmarks for the first time the number of annual deaths caused globally by pollution from marine vessels, with coastal regions in Asia and Europe the most affected.

Conducted by James Corbett of University of Delaware and James Winebrake from Rochester Institute of Technology, the study correlates the global distribution of particulate matter—black carbon, sulfur, nitrogen and organic particles—released from ships’ smoke stacks with heart disease and lung cancer mortalities in adults. The results indicate that approximately 60,000 people die prematurely around the world each year from shipping-related emissions. Under current regulation, and with the expected growth in shipping activity, Corbett and Winebrake estimate the annual mortalities from ship emissions could increase by 40 percent by 2012.
Corbett and Winebrake’s results come in the midst of current discussions by the International Maritime Organization to regulate emissions from ships.
“This study will help inform policymakers about some of the health impacts associated with ship emissions and the long range transport of those emissions to population centers,” says Winebrake, chair of RIT’s Department of Science, Technology and Society/Public Policy। “We now have a benchmark by which we can begin to evaluate the benefits of emission reduction policies.”

Annual deaths related to shipping emissions in Europe are estimated at 26,710, while the mortality rate is 19,870 in East Asia and 9,950 in South Asia. North America has approximately 5,000 premature deaths, concentrated mostly in the Gulf Coast region, the West Coast and the Northeast, while the eastern coast of South America has 790 mortalities.
Ships run on residual oil, which has sulfur content thousands of times greater than on-road diesel fuel. “Residual oil is a byproduct of the refinery process and tends to be much dirtier than other petroleum products,” Winebrake says.
“We needed to know what the benefits are of cleaning up this fuel,” he explains. “Now we can evaluate the human health impacts of policies to require low-sulfur fuels for the shipping industry or that require ships to put emissions control technology on their vessels. Our study will help inform this policy debate.”
Up until recently, researchers had little information with which to work; emissions data for marine vessels had to be linked with data tracking the movement of these vessels around the world. In their report, Corbett and Winebrake mapped marine pollution concentrations over the oceans and on land, estimating global and regional mortalities from ship emissions by integrating global ship inventories, atmospheric models and health impacts analyses.
The focus on long-term exposure to particulate matter in this study does not extend to impacts on children or other related health issues such as respiratory disease, asthma, hospital emissions and the economic impact of missed workdays and lost productivity.
“Our work will help people decide at what scale action should be taken,” says Corbett, associate professor of marine policy at University of Delaware. “We want our analysis to enable richer dialogue among stakeholders about how to improve the environment and economic performance of our freight systems.”
This study was supported in part by the Oak Foundation, the German Helmholtz-Gemeinschaft Deutscher Forschungszentren and by the German Aerospace Center within the Young Investigators Group SeaKLIM.
Research article: “Mortality from Ship Emissions: A Global Assessment” is scheduled to appear in the Dec. 15 issue of Environmental Science and Technology, the journal of the American Chemical Society.
Adapted from materials provided by Rochester Institute of Technology.

Firefly fish for pollution monitoring

Schools of glowing fish could become a tool for monitoring water quality. The US government's National Institute of Environmental Health Services (NIEHS) has been funding research into fish that glow like a firefly when exposed to polluted water.Fireflies light up when an enzyme in their stomach called luciferase oxidises luciferin. The NIEHS hopes to insert luciferase-producing genes from fireflies into the eggs of zebrafish. Other genes would then be injected into the zebrafish making them sensitive to a particular pollutant. This could make the fish generate luciferase in the presence of mercury, for example.The genetically modified fish could then be dangled in a cage into water at risk of pollution. After half an hour they could be removed and dunked into a solution containing luciferin. If they start to glow, it means the water is polluted. The brightness of their glow could even reveal just how bad the pollution is. And the fish should survive the process for re-use later.

An US patent was claimed for this work and the abstract is as follows

The present invention provides methods and systems that uses transgenic zebrafish with an easily assessable reporter gene under the control of pollutant-inducible DNA response elements. Transgenic zebrafish, carrying pollution-inducible response elements, are placed in the water to be tested, and the contaminants become bioconcentrated (generally 1,000- to 40,000-fold, relative to the water) in the tissues of the fish thereby activating specific response elements, which up-regulate the LUC reporter gene. Fish are then removed from the test water and placed immediately in a luminometer cuvette and incubated with luciferin. Luciferin is rapidly taken up into the tissues of the fish, oxidized by luciferase, and light is produced. The luminescence is proportional to the environmental concentration of the pollutant (to which the fish had been exposed), which drives the expression of the LUC gene by means of the various DNA motifs. The luminescence is quantitated in the luminometer. In each response element-containing construct, a specific class of polluting chemicals, allowing for differential identification of pollutants in a complex mixture activates the expression of the LUC gene. This assay does not require killing the fish and allows for repeated analysis of the same site with the same fish. The sensitivity of the system can be manipulated by varying the sequence of the response element.

Like to see the full US patent document for this work click me