Dear EarthTalk: What is the environmental impact of an oil spill into the sea?
—Sarah, Baton Rouge, LA
According to the U.S. Environmental Protection Agency (EPA), the United States uses approximately 250 billion gallons of petroleum products every year. With so much demand, it is not surprising that spills do occur during various stages of production, transportation and distribution. A spill"s specific environmental impact depends upon the type and amount of oil, and the local conditions.
According to Alaska Sea Grant, a marine research program at the School of Fisheries and Ocean Science at the University of Alaska Fairbanks, oil spills into water place an enormous variety of animals and plants at severe risk from smothering and poisoning. The group says that the infamous 1989 Exxon Valdez disaster off the coast of Alaska—America"s largest oil spill to date—directly killed between 300,000 and 645,000 birds, including bald eagles and many types of ducks and other sea birds.
The Valdez spill also wreaked untold harm on the health and reproductive success of surviving birds in the surrounding area. Seals, otters, killer whales and fish were also killed and injured in alarming numbers. Sea Grant says the oil critically damaged beach ecosystems and contaminated sediments, and that the accident seriously disrupted local economies dependent upon fishing and sightseeing. Beyond the immediate effects of such a spill, oil particles can linger in the environment for decades.
According to Judith McDowell of the Woods Hole Oceanographic Institution, less than 10 percent of the oil that makes its way into marine environments is actually due to spills like that of the Exxon Valdez. Most oil ends up in seawater from a combination of natural seeps from the ocean floor and "run-off" from both offshore drilling facilities and land-based automobiles and machinery. Indeed, a significant amount of oil eventually makes its way into both marine and freshwater environments—including underground aquifers and other sources of drinking water—from the millions of cars and trucks that routinely leak oil onto driveways, parking lots and roads. Scientists do not have enough data to assess the long-term threats that such a persistent presence of oil has on local ecosystems, but they surmise that it can have significant impact on the health of a wide range of plant and animal populations, as well as on human health.
To help mitigate damage from oil spills following the Exxon Valdez accident in 1989, Congress passed the Oil Pollution Act (OPA) in 1990, establishing provisions to improve the federal government"s ability to respond to spills. Congress also created the Oil Spill Liability Trust Fund, which provides up to $1 billion per accident to cover removal costs or damages resulting from discharge of oil. The EPA also performs inspections and requires oil storage owners to report their prevention policies.
CONTACTS: U.S. EPA Oil Program, (800) 424-9346, www.epa.gov/oilspill/index.htm; Alaska Sea Grant, (907) 474-7086, http://www.uaf.edu/seagrant; Woods Hole Oceanographic Institution, (508) 289-2252, www.whoi.edu.
Dear EarthTalk: I’ve heard that compact fluorescent light bulbs, known for their long life and low energy consumption, contain toxic mercury. Is this true and, if so, what precautions should I take when disposing of them?
—Greg Newswanger, Freedland, MD
Compact fluorescent light bulbs do contain small amounts of mercury vapor, which, when catalyzed by voltage, give off ultraviolet energy, the key building block for generating light. When these bulbs burn out or break, they need to be discarded responsibly so as to avoid unleashing mercury into the environment and food chain.
Mercury—a toxic metal known to cause brain, spinal cord, kidney and liver damage in humans—does not break down easily and, once airborne, often finds its way into groundwater, rivers and the sea, where it can cause a host of contamination issues for wildlife and people alike.
The first thing to do when a compact fluorescent bulb breaks is to open all the windows to disperse any mercury vapor that may have escaped. Then put on gloves, sweep up the fragments, and wipe the area with a disposable paper towel. Using a vacuum is a bad idea, as it will only stir up any lingering airborne mercury. Lastly, the fragments should be sealed into a plastic bag and recycled or disposed of.
The best way to dispose of burned-out or broken compact fluorescent bulbs is to take or mail them (in the sealed plastic bag) to a mercury recycling facility. The website of the Association of Lighting and Mercury Recyclers provides contact information for locating such facilities state by state. If mercury recycling is not an option in your area, the bulb or fragments should be placed in sealed plastic bags and disposed of at your local Household Hazardous Waste (HHW) collection site.
Ironically, compact fluorescent bulbs are responsible for less mercury contamination than the incandescent bulbs they replaced, even though incandescents don’t contain any mercury. The highest source of mercury in America"s air and water results from the burning of fossil fuels, such as coal, at utilities that supply electricity. Since a compact fluorescent bulb uses 75 percent less energy than an incandescent bulb, and lasts at least six times longer, it is responsible for far less mercury pollution in the long run. A coal-burning power plant will emit four times more mercury to produce the electricity for an incandescent bulb than for a compact fluorescent.
CONTACTS: Association of Lighting and Mercury Recyclers, www.almr.org; Earth911.org; EPA Household Hazardous Waste Page, www.epa.gov/epaoswer/non-hw/muncpl/hhw.htm; EPA Fact Sheet: Mercury in Compact Fluorescent Lamps, www.nema.org/lamprecycle/epafactsheet-cfl.pdf