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Field Notes
News Articles
Migration: A Wing and a Prayer
Chemistry: Corexit Break Down
Interview: Cool Mix with DJ Spooky
Solar Power: Space Race
Food: Carp for Dinner
Energy: Catching a Wave

Briefs
Chimpanzee sexcapades; surfing crocodiles; lazy crows; cologne for cats; more.

Plane: Natalie Fobes/Corbis

Chemistry
Break Down
Sprayed from planes and pumped into the Gulf of Mexico to disperse oil, Corexit has literally colored our perception of the spill—it gives the crude it envelops an orange-brown hue. The chemical cocktail breaks the oil down into smaller globules that microorganisms can ingest and degrade faster than if it remained in a slick. Corexit is EPA-approved and has been used in other oil spills, but its long-term effects on human health and the environment are largely undetermined. EPA tests have found that the dispersant is “practically nontoxic” for fish and “slightly toxic” for shrimp; however, the agency hasn’t yet tested its toxicity when mixed with oil. “We don’t know what the broad ecosystem effects will be,” says David Andrews, a chemist at the nonprofit Environmental Working Group. “That’s still a big unknown, and we’ve made the Gulf of Mexico a giant science experiment.” BP has poured about two million gallons of Corexit into the Gulf, leading scientists to speculate that the chemical bath could result in toxic zones where life can’t survive. Here’s a look at Corexit’s ingredients.—Susan Cosier

Propylene glycol
This substance is a food coloring and flavor solvent. It’s also used in the paint and plastics industries, and helps create artificial smoke used in movies and theaters.

Dioctyl sodium sulfosuccinate
Found in cosmetic products, gelatin, and beverages, it functions as a moisturizer.

2-butoxyethanol
This clear liquid, which smells like ether, is in paint thinners, varnish removers, herbicides, liquid soaps, household cleaners, and cosmetics. Studies show that high doses can cause reproductive problems in animals.

Sorbitan oleate
This shows up in skin cream, body shampoo, and juice. (It’s an emulsifier, so it binds substances together.)

Dipropylene glycol monobutyl ether
Used in household cleaners, disinfectant sprays, paints, and adhesives, this chemical can irritate skin and eyes. High doses have been shown to be lethal to fish.

Polysorbate-80
Both mouthwash and face lotion contain this chemical, which is also used as an emulsifier in food.

Distillates (petroleum), hydrotreated light
These are put in cleaners and air fresheners. OSHA set a limit of 500 parts per million of petroleum distillates for workplace air.

Polysorbate-85
This substance is commonly found in face lotions, body lotions, and tanning lotions.

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