About a third of US rivers contaminated with agricultural runoff

The Snake River flowing through Grand Teton National Park. Photo by Ansel Adams (courtesy of U.S. National Archives).

At least our rivers don’t light on fire anymore. Inspired by a well-publicized fire on the Cuyohoga River in 1969, the passage of the Clean Water Act in the US led to huge reductions in water pollution. Despite those positive strides, maintaining water quality requires ongoing attention. A new survey of streams and rivers, performed by the EPA, provides a greater sense of the scale of the challenge. While industrial pollution, like mercury, remains a concern, agricultural runoff, in the form of sediment and fertilizers, is now far more widespread.

Water quality monitoring is performed by states using a variety of methods, which can make it difficult to accurately compile the national picture. The US Environmental Protection Agency has started carrying out nation-wide surveys to provide consistent, standardized snapshots of water quality. Following on the heels of the 2006 Wadeable Streams Assessment, the EPA recently released a draft comprehensive survey of streams and rivers.

The legwork was carried out in 2008 and 2009 by 85 crews that visited 1,924 sites in the lower 48 states. The sites were selected at random using an algorithm that ensured a representative sample. At each site, crews evaluated the stream’s surroundings, inventoried the species present, and collected samples for chemical analysis.

Read 10 remaining paragraphs | Comments

Anti-anxiety drugs in wastewater impact fish behavior

Washington.edu

Benzodiazepines are a highly effective group of pharmaceutical drugs that help millions of people cope with anxiety, insomnia, and panic disorders each year. These drugs work by binding to receptors in the brain and enhancing the effect of a neurotransmitter called GABA.

But humans aren’t the only animals with GABA and GABA receptors; several other species—including many types of fish—are similar to us in this aspect of their brain chemistry. And, thanks to the huge amount of prescription drugs that are flushed down the drain (American medical care facilities alone may flush as much as 250 million pounds of pharmaceuticals a year), these species are inadvertently being exposed to high concentrations of benzodiazepine in rivers, lakes, and streams.

In this week’s issue of Science, a group of researchers shows exposure to these drugs can cause significant behavioral changes in fish, changes that could potentially alter ecosystem dynamics.

Read 8 remaining paragraphs | Comments

Urban wind flows deposit pollutants in repetitive patterns

Shutterstock

Mathematicians have published a paper suggesting that pollutant-carrying urban flows—winds that navigate city obstacles—deposit particles in repetitive patterns leading to build-ups in specific city locations.

As wind weaves through the everyday fumes generated by a city, it gathers particles from car exhausts, dust and other minute pollutants. Using a mathematical dynamical systems formula dictated by Lagrangian mechanics, the Arizona State University and University of Notre Dame team plotted the random motion of these particles for the first time. The model, built to simulate the wind motion over long periods of time, found that the process was not random at all—a coherent pattern rapidly emerged, demonstrating that the particles were repeatedly deposited in the same area.

"In previous studies, the existence of these patterns in fluid flows was only verified with idealised 'theoretical' flows," said lead author Wenbo Tang. "It was not known if such structures were robust enough to manifest in the environment."

Read 4 remaining paragraphs | Comments

Hospitals can save money just sorting their trash

A report recently published in the Canadian Medical Association Journal suggests that hospitals could save considerable sums of money by adopting a handful of common sense measures to reduce waste. The report asserts that 50 to 85 percent of regular waste is incorrectly disposed of as biohazard waste, which is estimated to cost eight times more to process. This alone can result in a hospital spending tens of thousands of dollars per year in unnecessary costs.

Operating rooms are responsible for between a fifth and a third of a hospital's waste while consuming a much smaller proportion of a hospital's budget. It's on the operating room that Yoan Kagoma MD and co-authors from University of Western Ontario’s medical school have fixed their gaze. Using 65 prior studies, the team has come up with a series of money-saving waste management recommendations for hospitals and health care institutions.

The single most effective cost-saving measure a hospital can adopt is to ensure that its waste is properly segregated, the report claims. Biohazard waste costs an estimated $963 per ton to process compared to the $121 per ton for regular waste. At most, biohazard waste should make up 15 percent of a hospital's waste. But the report claims that, due to a simple "lack of awareness" among hospital staff, between 50-85 percent of the remaining non-hazardous waste is disposed of in the same costly manner (though it should be noted this finding is based on a paper published in 1996). By properly segregating waste in its operating rooms, the University of Pittsburgh's Magee-Womens Hospital saved more than $89,000 in 2010.

LA smog: more cows than cars?

Much to the chagrin of California tourism promoters, smog is likely one of the things you picture when you think about the city of Los Angeles. The haze of pollutants that often hangs over the region is more than just an eyesore; it's a source of considerable respiratory stress. And where does that air pollution come from? Smokestacks, tailpipes, and cows. You read that right—cows. In fact, a new study estimates that cows contribute at least as much as automobiles.

There are two main factors that control the formation of smog. The first is the air pollution. This includes a range of volatile organic compounds, as well as oxides of nitrogen (referred to as NO_x compounds). These pollutants react in sunlight to produce the ground-level ozone that triggers asthma advisories. The second necessary condition is stagnant air. A stiff breeze moving through the city will clear away pollution before it can collect. Areas that experience smog typically have the right topographical and meteorological conditions for air masses to hang around for a while.

Read the comments on this post

LA smog: more cows than cars?

Much to the chagrin of California tourism promoters, smog is likely one of the things you picture when you think about the city of Los Angeles. The haze of pollutants that often hangs over the city is more than just an eyesore; it's a source of considerable respiratory stress. And where does that air pollution come from? Smokestacks, tailpipes, and cows. You read that right—cows. In fact, a new study estimates that cows contribute at least as much as automobiles.

There are two main factors that control the formation of smog. The first is the air pollution. This includes a range of volatile organic compounds, as well as oxides of nitrogen (referred to as NO_x compounds. These pollutants react in sunlight to produce the ground-level ozone that triggers asthma advisories. The second necessary condition is stagnant air. A stiff breeze moving through the city will clear away pollution before it can collect. Areas that experience smog typically have the right topographical and meteorological conditions for air masses to hang around for a while.

A large portion of the small particles, or aerosols, that contribute to the haze are comprised of ammonium nitrate (NH₄NO₃). The nitrate comes from NO_x emissions, but the ammonium mostly comes from a couple specific sources.

EPA’s carbon rules to grandfather existing coal plants, limit new ones

Although the EPA has not yet made an official announcement, it is apparently ready to issue its first regulations regarding carbon dioxide emissions. The process dates back to the Clinton years, when states first asked the EPA to use the Clean Air (CAA) act to regulate greenhouse gasses as pollutants, with carbon dioxide getting extra attention due to its role in ocean acidification. After years of delay, the Supreme Court ruled that the EPA must determine whether CO₂ is a pollutant according to the CAA's definition. The Bush Administration's EPA found that it was, but its findings were never made public or acted upon (they have since been obtained by the press). The Obama EPA reached a similar conclusion, but deferred acting on it, at least until now.

According to various press reports, the EPA has been briefing stakeholders on its planned regulations. They would put the limit on emissions at 1,000 pounds of carbon dioxide per megawatt-hour of electricity produced, but will only apply to new construction. A modern natural gas plant should be able to meet that limit with little difficulty. Most coal plants in existence, however, produce roughly double that amount, and will not be able to meet it without adopting some form of carbon capture and storage technology.

The regulations will send a clear signal to the market: either find a way to capture carbon cheaply, or don't build new coal capacity. Although they do very little for existing emissions directly, they're likely to have an indirect effect, since many of the oldest and least efficient plants in use burn coal at costs that are significantly higher than that of natural gas. In addition, the renewable energy mandates adopted by many states will displace some existing power sources; these old plants will again be the primary target.

Read the comments on this post

New study suggests cap-and-trade results in decreased innovation

Among those interested in addressing the problem of climate change, one of the primary debates is about the best way to induce the private sector to develop innovative technologies. Although some favor a simple carbon tax, the US' success with a cap-and-trade system has led to its use both in Europe and in regional systems within the US. A new analysis of past US programs, however, suggests that cap-and-trade hasn't quite been the success many think it is. Its rapid early gains have been followed by a period of stagnation.

The US implemented cap-and-trade systems in the 1990s as a response to the problem of acid rain. Chemicals produced by combustion of fossil fuels (primarily coal) had previously been regulated by standard environmental regulation. However, over the course of the 1990s, SO₂ and NO_x were both subject to a cap-and-trade system that gave industries the option of taking different approaches to the control of these emissions. All significant sources of these chemicals were given allowances targeted to keep the total emissions below levels deemed acceptable. Innovators that cut their emissions substantially could sell their allowances to sources that found it too difficult or expensive to do so.

On some levels, this was a significant success. Emissions dropped and the cost of reaching that goal turned out to be far less than many had predicted. But Berkeley's Margaret Taylor has now gone through the numbers and found data suggesting not all is as rosy as it appears.

Read the comments on this post

Test of 400 options shows we can save money while limiting climate change

If a group of scientists announced that reducing emissions of some pollutants would prevent global warming, it wouldn’t make headlines—we’ve been hearing that for years when the pollutant is carbon dioxide. However, if they added that those reduced emissions would also prevent millions of premature deaths per year and increase annual crop yields by tens to hundreds of millions of tons, you would probably take notice. But the part that will really blow your mind—and what might make some people reconsider their stance—is that all of this could be done at a profit.

A large group of scientists identified 14 emissions reduction measures—out of around 400 considered—that primarily reduce ozone and black carbon (BC; think soot) using existing technology. The study was authored by Drew Shindell, of NASA Goddard and Columbia University, who had 23 coauthors from a total of 13 different institutions around the world (from countries including the US, UK, Italy, Austria, Thailand, and Kenya). The group concluded that the economic benefits of improved air quality and diminished global warming exceed the typical costs of these 14 approaches.

Read the comments on this post