Frog and fish reveal how humans might react to pharmaceuticals in water, scientist says
By Robin Grant
Science Reporting Class, Carleton University School of Journalism
Fish and frogs aren’t cute and cuddly. They aren’t even the often-thought-of test subjects in scientific experiments. But that doesn’t deter University of Ottawa’s Research Chair in Neuroendocrinology, Dr. Vance Trudeau, who studies the animals’ reproductive system – or lately – both animals’ lack of reproduction.
In fact, fish and frogs play the key role in Trudeau’s award-winning research in the emerging field of endocrine disruption – the science of how pollutants affect the hormone system in animals, including humans.
Endocrine disruption was not coined as a science until the ‘80s. But the public first learned about the phenomena in the 1950s with the pesticide called DDT.
One of the chemical’s most infamous affects on animals was seen in the eggshells of predatory birds. After coming into prolonged contact with the chemicals, birds like the bald eagle, the peregrine falcon and the brown pelican could not lay a shell thick enough for it to sit on and hatch the chick.
While DDT is still used in controlled circumstances, mainly to combat malaria in developing countries, the public outcry on the effect the pesticide had on wildlife resulted in its discontinued use in many countries, including Canada and the United States.
Today, Trudeau’s research in endocrine disruption focuses specifically on how pharmaceutical pollutants in water affect fish and frogs.
Fish are important in his study, because being purely aquatic animals, they are completely dependent on water. This means they can’t escape pollutant-saturated water, and absorb the chemicals into their bodies.
“Fish can’t avoid pollutants. So they’re are like a monitor. They take up pollutants. They can metabolize some, but they keep others. And they’re really heavily affected,” Trudeau says.
One of Trudeau’s most significant experiments used goldfish to look at how the common antidepressant Prozac, found in mass amounts in human drinking water, inhibited the animal’s sexual activity.
Published in the journal Aquatic Toxicology in 2010, the study found that male goldfish exposed to water treated with Prozac experienced a 50 per cent decrease in sperm production.
The research tested fish in two levels of treated water for week-long periods. Water type one had the same levels of Prozac found in sewage effluent. The other level had an even higher Prozac concentration. In both levels, the male frogs didn’t respond when the females released the chemical pheromones. In a natural environment, the female’s natural bodily function should have induce the males to produce sperm.
Trudeau is interested in frogs for two reasons. One reason is because there is a worldwide species decline, and he has conducted a study that helps a certain species of frog reproduce in captivity. And two, because the tadpole, as a scientific model, closely resembles the human embryo.
“Frogs are interesting because most are aquatic at the tadpole stage. The tadpole stage is like an embryo. It’s like studying the human embryo, but it’s easier. And that’s the most sensitive phase of life.”
According to Trudeau, because the tadpole is so sensitive it reacts to powerful pharmaceutical pollutants, like estrogen-based, oral contraceptives found in drinking water. With a hormonal system similar to humans, frogs are affected by the drugs in similar ways.
“The concentration of estrogen in the skin ends up affecting its sexual development. For example, male tadpoles retrain ovary cells in their testicles,” Trudeau says.
And while the public can’t seem to find an economic benefit in protecting frog species, Trudeau considers the species decline to be one of the foremost issues in environmental science, because of the key role the frogs play in the ecosystem.
“They play a very important role in the ecosystem. They eat bugs and other pests, which have caused problems in farming,” he says. “Other animals eat them; they are a food source for humans.”
In 2011, Trudeau used a hormone trick that made it possible to breed certain species of frog in captivity – a feat nearly impossible to do in some species.
“In that case, I adapted fish breeding techniques to leopard frogs, and it worked,” he says. The technique was later dubbed: “Vance’s Love Potion.”
So how are pharmaceuticals getting into the waterways and causing reproductive deficiencies in fish and frogs, which results in the worldwide decline of both species?
Trudeau says it happens because sewage treatment plants neglect to separate the chemicals, which contain hormones like estrogen, from the waste. The chemicals filter through the system, and are released back into lakes and rivers. And bacteria convert it back into a biologically active form, containing the original hormone.
“The sewage system is good for some things, but it was not designed for removing these chemicals,” he says.
Also, certain studies suggest we are entering a “vicious cycle” where the presence of pharmaceuticals in aquatic animals results in their re-ingestion by humans, which could cause damages to human fetuses.
And Trudeau agrees.
“If [the chemicals] get into the drinking water and the fish, for example, some of these chemicals cause harmful defects in humans,” he says.
Trudeau points to two main ways to address the problem. The first is that people need to ask their doctor if the drug they are prescribed is really necessary. The second is to improve the purification systems.
Canada has a cooperative network, which includes the University of Ottawa, that is developing technologies that eliminate certain pharmaceuticals in purification plants.
“Upgrading sewage treatment plants will be expensive, but in the long run, it is necessary and effective,” Trudeau says.
Ultimately, Trudeau hopes his work will contribute to helping two aquatic creatures that are defenseless against human-caused pollutants. Not only that, because both animals are so integral to to the food chain, their disappearance would be an ecological disaster. So, in the end, his science just might help humans, too.
Science Behind Sandy
By Robin Grant
Written for a Science Reporting Class, Carleton School of Journalism
When Hurricane Sandy made landfall south of Atlantic City, New Jersey on October 29th, it had barreled north toward the East Coast from the Caribbean, leaving disaster in its wake.
Around the same time, a cold front moved across the middle of the United States, bringing cold temperatures and snow.
In a rare meteorological phenomenon, the two weather systems collided as the hurricane came ashore at 8 p.m. EST. The National Hurricane Center in the U.S. received reports of hurricane-force winds gusting over Long Island and the New York metropolitan areas.
The hurricane’s massive and unprecedented storm surge – the wall of seawater pushed ashore by Sandy’s winds and low atmospheric pressure – caused more damage to the East Coast shores than its powerful surface winds, torrential rains and mountain snows.
New York City and the surrounding neighborhoods were inundated with rushing seawater flowing in from the Hudson River. Lower Manhattan, parts of Brooklyn, Queens and Staten Island flooded. Many neighborhoods on the New Jersey coastline were destroyed. Flash floods, falling trees, hurricane-force winds and power outages caused billions of dollars in damage, and killed and injured people in the affected areas.
Three days later, as the city grappled with the catastrophic damages, New York City Mayor Michael Bloomberg, who had remained undecided on whom to back in the election, penned an opinion piece addressing the issue of climate change, and announcing he backed President Barack Obama. The reason, he gave, was because the President showed more leadership on the issue than the competitor, Governor Mitt Romney.
“We need leadership from the White House. And over the past four years, President Barack Obama has taken major steps to reduce our carbon consumption, including setting higher fuel-efficiency stands for cars and trucks,” Bloomberg wrote. “His administration also has adopted tighter controls on mercury emissions, which will help to close the dirtiest coal power plants, which are estimated to kill 13,000 Americans a year.”
As the second major storm to hit land in New York City in 14 months, Hurricane Sandy determined Bloomberg’s vote and caused him to seriously address the effects of global warming.
Across the United States scientists weighed in on whether the hurricane was the result of global warming and whether storms like it would hit coastal areas more frequently in the future. In Canada, the reaction in the scientific community was the same.
In a blog post for Sierra Club Canada, Paul Beckwith, a University of Ottawa Ph.D. candidate in climatology, wrote about what he called Sandy’s “unnatural behavior.”
Beckwith described how as Sandy moved northward off the East Coast, it uncharacteristically shifted left and hit land. Under normal circumstances, the natural progression of a hurricane in the Northern hemisphere would be to move right, because of the tilt of the earth on its access.
Beckman attributed this “abnormality” to what he called an increase in “nonlinearity events” in global weather patterns, resulting from rising temperatures and melting ice caps.
In short, he said, “global warming.”
According to Beckwith, the increase in nonlinearity means that weather patterns like the new trajectory of Hurricane Sandy will become more unpredictable and unprecedented.
“We’re leading toward a completely different climate system distinguished by old climate verses new climate. The statistics of weather patterns are completely changing,” Beckwith said. “If you think this storm is bad, get used to it.”
In an article for the Montreal Gazette, Damon Matthews, a professor in the department of geography at Concordia University and a member of the Global Environmental and Climate Change Center, agreed with Beckwith that rising temperatures cause disruptions in global weather patterns.
“We are living in a new world. The globe is warming, and will continue to do so as long as we continue to fill the atmosphere with greenhouse gases,” Matthews wrote.
“With a warming climate will come increasingly bizarre, and unusual, weather phenomena. Against this backdrop, every strange and bizarre weather event that occurs does so in the context of global warming.”
In an interview, Matthews said that although scientists can’t definitively say Hurricane Sandy was caused by global warming, he said scientists do confirm that violent storms raise serious questions about what lies ahead.
And the storm, he said, was stronger than it should have been because of rising temperatures.
“Every record from every credible source tells us the temperature of the oceans are getting warmer. And it’s making hurricane weather worse.”
But not everyone espouses this view. There are scientists in Canada, and around the world, who call themselves the climate skeptics. Many of them belong to a group called the International Climate Science Coalition, an organization that promotes global warming skepticism.
A policy series put out by the International Climate Science Coalition states that climate science has been politicized which has boosted alarmism. In fact, some of these scientists have said the scientific foundation of human-caused global warming is exaggerated or false.
“The fundamental scientific foundation of the anthropogenic CO2 -caused dangerous global warming hypothesis is wrong or grossly exaggerated,” said Brian Pratt, a Professor of Geology at the University of Saskatchewan, in the organization’s series.
Tad Murty, a professor who specializes in Tsunami research at the University of Ottawa,said people should question the dominate view on climate change and whether it fueled the hurricane’s catastrophic effects.
“If you look at the Accumulated Cyclone Energy you see that Sandy is not that big,” he said. “These are the facts we have to look at.”
According to Murty’s research, there has been a worldwide decline in the number of large, destructive hurricanes in the last one hundred years. The problem with Sandy is a lack of preparation and people building homes in coastal areas prone to hurricanes.
“I’m not minimizing the damage from Sandy. But the problem is lack of preparation. Three to four metres is not a big deal. You have to protect your post,” Murty said, referring to the great number of people living in coastal areas. “There needs to be civil engineering solutions, sea walls. Sea walls can completely it stop it. You can design seawalls that completely stop it.”
Bill McKibben tells Daily Beast how to talk to climate skeptics:
Invasive Ant Finally Gets Its Real Name
By Robin Grant
Written for a Science Reporting Class, Carleton School of Journalism
An invasive ant ravaging Gulf Coast states for over a decade is now confirmed to be a species of a crazy ant native to South America and the Caribbean, according to a recent study.
And classifying the far-ranging pest was a nuance, too, as researchers had to compare the miniscule genitalia of many different ant types to determine this one’s scientific moniker.
“Sort of a running joke among entomologists who do taxonomy is that we spend a lot of time looking at the naughty bits of insects,” said study researcher John LaPolla, a taxonomist at Towson University to LiveScience in September. “And the reason for that is because there are often some distinct features that help separate the species.”
Popularly known as the Rasberry crazy ant, the ant is named after Tom Rasberry, the local exterminator in South Texas who discovered it.
In 2002, Rasberry noticed a growing number of ant colonies housed insects that swarmed rapidly and moved in erratic circles. In his early attempts to eradicate the pest, Rasberry said he knew the infestation would spread and reach uncontrollable numbers.
“The reproductive capability of this ant was unlike anything I’d ever seen,” Rasberry said.
In the years since its discovery, the ant has spread from South Texas to 21 counties and into parts of Mississippi and Louisiana.
The ants cause serious problems in rural communities, such as shorting out important electrical equipment, asphyxiating small livestock and causing ecological damages unprecedented in the region.
“Once the ants get into rural communities, they pretty much take out the entire food chain,” Rasberry said.
In the study released in September, LaPolla and his colleagues compared the body parts of several ants to pinpoint this ant’s exact genus. They compared specimens of the Rasberry crazy ant with another species called Nylanderia, which are found in North America, the Caribbean and tropical zones in Europe, Asia and Africa.
The classification process was difficult because two possible species, the N. fulva and N. pudens, have almost similar worker ants, according to the study.
So, by using genetic data and measurements of the ant bodies, the researchers determined the ants’ species by examining the male ants’ genitals.
Looking at the genital features and genetic data, the scientists learned that the Rasberry crazy ant belongs to the N. fulva category found in South America.
The study argues that knowing the ant’s scientific classification is important to deal with invasive species that are a consequence of human-caused global change. The study also says the findings could help uncover ways of eradicating the pest. Determining the species point of entry into the country, which is assumed to be the Port of Houston, can give custom officials something to watch for.
Back in South Texas, Rasberry still deals with the ants on a daily basis. He says the new research should help find and fund ways of controlling the ant, which is too expensive for citizens to undertake on their own.
He said he is angry the government did nothing about the infestation when he first reported it 2002.
“Government entities are inept. They wait until after the problem happens before they respond,” he said. “Now we’ll never get rid of the ants.”