Stories tagged Environmental Protection Agency

May
02
2010

BP oil spill projection for May 3, 2010
BP oil spill projection for May 3, 2010Courtesy uscgd8
Chemicals known as dispersants are now being used against the ever increasing amount of oil leaking out of a deep water well head. Dispersants help break the larger masses of oil into smaller droplets which will mix into the water. These dispersants are being sprayed onto the surface slicks and are also being injected directly into the oil flowing out almost a mile under the surface.

Officials said that in two tests, that method appeared to be keeping crude oil from rising to the surface. They said that the procedure could be used more frequently once evaluations of its impact on the deepwater ecology were completed. New York Times

How do chemicals disperse the oil?

Dispersant chemicals contain solvents to assist it in dissolving into and throughout the oil mass and a surfactant which acts like soap. Surfactant molecules have one end that sticks to water and one end that sticks to oil. This, along with wave action, breaks masses of oil into droplets small enough that they stay suspended under water, rather than floating back to the surface.

Are these chemicals safe?

Such cleanup products can only be used by public authorities responding to an emergency if they are individually listed on the National Contingency Plan Product Schedule.

Many of the first dispersants used in the 70s and 80s did show high toxicity to marine organisms. However, today there is a wealth of laboratory data indicating that modern dispersants and oil/dispersant mixtures exhibit relatively low toxicity to marine organisms.
On occasions the benefit gained by using dispersants to protect coastal amenities, sea birds and intertidal marine life may far outweigh disadvantages such as the potential for temporary tainting of fish stocks. ITOPF

Here is a link to one product on their list (Oil Gone Easy Marine S200

Hard choices

According to National Geographic News, "Dispersants only alter the destination of the toxic compounds in the oil." Moving the oil off the surface protects the birds and animals along the shoreline but will increase the oil exposure for fish, shrimp, corals, and oysters. I hate to mention what hurricanes will do to this situation.

Jul
04
2009

Awesome fireworks require a chemical bath

Fireworks color
Fireworks colorCourtesy Camera Slayer
Awesome Fourth of July fireworks can be viewed from our Science Museum of Minnesota each year during the Taste of Minnesota celebration. Fireworks are often shot over water to minimize fire danger. Ever wonder what kind of chemicals rain down into the Mississippi River during a fireworks display?

Chemical coloring

Part of learning chemistry is to understand what is called the flame test. Unknown chemical compounds, when heated in a flame, will generate different colors. Lithium yields red, copper gives blue or blue-green, sodium gives yellow, aluminum and titanium produce the whites.

Making fireworks more green

Chemists are attempting to make fireworks less harmful to the environment.

Perchlorates, which are used to help the fireworks’ fuel burn, were named in an EPA health advisory earlier this year (which recommended a maximum of 15 micrograms per liter of drinking water), as they have been linked to disruption of the thyroid gland.Scientific American

A 2007 U.S. Environmental Protection Agency (EPA) study found that perchlorates spiked by up to 1000 times normal after the fireworks display and took 20 to 80 days to return to normal depending on surface temperatures.

How to make fireworks whistle, crackle, and pop

Click this link where Live Science explains some of the strange ingredients in fireworks like:

"chemists add bismuth trioxide to the flash powder to get that crackling sound, dubbed "dragon eggs." Ear-splitting whistles take four ingredients, including a food preservative and Vaseline.
Tubes, hollow spheres, and paper wrappings work as barriers to compartmentalize the effects. More complicated shells are divided into even more sections to control the timing of secondary explosions.