Credit: NASA Earth Observatory
Gulf drilling disaster
The biggest oil spill in U.S. history began April 20, when an explosion and fire on the Deepwater Horizon offshore drilling platform sent oil spewing into the Gulf of Mexico at rates at times exceeding 65,000 barrels a day (SN Online: 9/23/10). By the time the well was capped 12 weeks later, an estimated 5.2 million barrels of oil had been released, all but 800,000 of which ended up in the water. Much of the oil drifted in diffuse subsea plumes (SN: 7/3/10, p. 5) that may have contained twice as much natural gas as oil (SN: 10/9/10, p. 10). Although native bacteria began degrading the oil (SN: 9/11/10, p. 5), much of the gas — especially methane — was expected to prove more resistant to rapid biodegradation. In late September, scientists reported that significant quantities of oil had landed in sediment or were headed there (SN Online: 9/28/10), where the crude is expected to resist breakdown.
Paper chase Bisphenol A, an estrogen-mimicking compound, has been found in the paper used for many store receipts (SN: 8/28/10, p. 5). The compound is linked to a variety of health concerns including heart disease in adults (SN: 2/13/10, p. 13) and increased risk of diabetes in pregnant animals and their young (SN Online: 5/19/10). Health concerns have led the federal government to recommend that parents minimize their kids’ exposure to plastics containing BPA (SN Online: 1/15/10), and led the only U.S. supplier of BPA-free cash register paper to tag its product (SN Online: 11/8/10).
Herbicide concerns Studies link water polluted by the common farm weed killer atrazine with birth defects and low birth weights in newborn humans (SN: 2/27/10, p. 18). Other work suggests the chemical itself can cause male tadpoles to develop into egg-laying adults that mate with other males (below) (SN: 3/27/10, p. 9).
Acid-spiked oceans Ocean acidification caused by increasing concentrations of dissolved carbon dioxide in seawater is found to threaten virtually all forms of marine life: compromising reproduction of corals (SN: 12/4/10, p. 10), confusing reef-dwelling fish (SN Online: 7/6/10) and reducing iron uptake by marine microorganisms, which may stifle the growth of phytoplankton that help absorb carbon dioxide emissions (SN Online: 1/14/10).
Dioxins down the drain Researchers show that once washed down the drain, triclosan, the germ-fighting chemical in most liquid hand soaps, can generate dioxins of unknown toxicity (SN Online: 5/18/10).
In with the new Replacements for the toxic flame retardants found in many household products can also escape into and persist in the environment (SN: 4/24/10, p. 12).
New thyroid threat Scientists link relatively high blood levels of PFOA, a common stain repellent widely used in everything from fabrics and carpeting to popcorn bags, with thyroid disease in people (SN Online: 1/22/10).
Diabetes link to pollution Air pollution may negatively influence blood sugar control in a large and growing number of people, new studies indicate (SN Online: 10/4/10).
Dumbfounded Researchers link lower IQs in kids to phthalates, chemicals found in some plastics and food packaging (SN Online: 4/5/10).
Infected tobacco Tests find hundreds of disease-causing bacteria species in major cigarette brands, suggesting a possible source of smokers’ respiratory infections (SN: 3/13/10, p. 10).
Pollutants and obesity Some babies exposed in the womb to a breakdown product of DDT grow fast, putting them on track for obesity, a study finds (SN Online: 10/5/10).
Forests falter In the last decade, carbon uptake by the world’s vegetation has slowed considerably, largely because of droughts (SN Online: 8/19/10).