Air Pollution

The California Air Resources Board on Thursday banned popular in-home ozone air purifiers, saying studies have found that they can worsen conditions such as asthma that marketers claim they help to prevent. The regulation, which the board said is the first of its kind in the nation, will require testing and certification of all types of air purifiers. Any that emit more than a tiny amount of ozone will have to be pulled from the California market.

That fresh, pine-scented mountain air that you happily breathe in the Sierra Nevada could be hazardous to your health. Samples taken by federal scientists in Devils Postpile National Monument , southeast of Yosemite National Park, show that ozone levels occassionally exceed state air pollution standards. “Even at remote eastern Sierra locations, ozone air pollution may be a problem for human and ecosystem health,” said Andrzej Bytnerowicz, a U.S. Forest Service research ecologist and lead author of a study recently published in the journal Atmospheric Environment.

The product: Dust, cigarette smoke, pollen and pet dander: With so many irritants floating around our homes and work places, clean air is a hot commodity. Americans spend hundreds of millions of dollars on furnace filters and air cleaners each year. Though some consumers are simply trying to bring a little extra freshness into their lives, many others hope that their investment will help relieve their asthma or allergies.

Two years ago researchers outfitted an electric Toyota RAV4 with a set of test instruments and drove back and forth near four Los Angeles County freeways between 4:30 a.m. and 6:30 a.m., sampling the air. The results confirmed that in the early morning, concentrated plumes of air pollution from freeways can travel more than a mile downwind, exposing more residents than previously thought to harmful pollution levels. Most previous air quality studies, based on measurements taken during the day or evening, have found that vehicle emission plumes generally blow no more than about 1,000 feet downwind from a major roadway before they break up. But in the hours just before sunrise, weather conditions are different.

While some Americans are congratulating themselves on switching to fuel-sipping cars, their old gas guzzlers just won't die. Lowered trade barriers are giving them new life south of the border. Thousands of used vehicles from as far away as Colorado and Missouri jam tiny car lots and auto salvage yards in this gritty border city. An estimated 25,000 families make a living here hustling U.S. castoffs. Among them is Jose Zavala, a wiry used-car dealer with a trucker's cap and an eye for bargains.

When UC Davis scientists collected air pollution particles in Fresno and then exposed laboratory mice to them, they found that one of the most toxic sources was the backyard grill. Along with particles from vehicle and wood-burning emissions, particulates from residential cooking had the greatest measurable impacts on mice lung function.   “That was like, wow!,” said Anthony Wexler, the study's coauthor and director of the Air Quality Research Center at UC Davis. “It's not that you're cooking; it's how you're cooking.

Nearly a third of older-model cars stopped for roadside smog tests in Southern California failed them, despite having received a passing grade at inspection stations within a year, a state audit has found. The results of those surprise inspections of 6,000 models manufactured before 1996 have led law enforcement officials to crack down on unscrupulous stations, step up fines and file more criminal charges. Legislation introduced in the California Assembly this week would allow the state to bar low-performing test stations from conducting smog checks.

Two years ago researchers outfitted an electric Toyota RAV4 with a set of test instruments and drove back and forth near four Los Angeles County freeways between 4:30 a.m. and 6:30 a.m., sampling the air. The results confirmed that in the early morning, concentrated plumes of air pollution from freeways can travel more than a mile downwind, exposing more residents than previously thought to harmful pollution levels. Most previous air quality studies, based on measurements taken during the day or evening, have found that vehicle emission plumes generally blow no more than about 1,000 feet downwind from a major roadway before they break up. But in the hours just before sunrise, weather conditions are different.

  Whether it's fog or smog, thousands of people have been delayed during the last few days by the almost-opaque air around Beijing Capital International Airport. The delays since Sunday evening at one of the busiest, most modern airports in the world raise questions about whether air pollution in China has gotten bad enough to derail the country's economic growth. Nearly 1,000 flights have been canceled and 10 highways in northern China had to be closed due to lack of visibility.

L.A.'s smog problem might not be as visible as it was in the bad old days of the 1970s and '80s, but city residents might be at an increased risk of stroke even at levels of pollution that meet EPA standards. Oh yeah, and memory loss. A new study published Monday in the Archives of Internal Medicine found that Boston residents experienced more strokes when exposed to “moderate” amounts of particulate air pollution, as opposed to “good” amounts of pollution, according to EPA standards.

WASHINGTON - President Obama's pick to lead the Environmental Protection Agency, Gina McCarthy, faced tough questioning from Senate Republicans at her confirmation hearing Thursday, in a clear signal to the White House that they will continue fighting environmental regulations as vigorously as they did in the first term. Obama's reelection, the gradual revival of the economy and the effects of climate change have not altered the viewpoint of some Republicans that climate change is suspect and environmental rules kill jobs.

Who knew that being a smoggy place might be good for business? Gov. Jerry Brown is in China, and one of the things he's pitching is California's expertise in dealing with smog. Because if there's one thing we have in common with the Chinese, it's air pollution. Now, some of what Brown is doing is, well, kind of squishy. As my colleague Anthony York reported : On Wednesday, he held a private meeting with Environmental Protection Minister Zhou Shengxian. They signed a nonbinding agreement "to enhance cooperation on reducing air pollution," the first such accord between China's government and a U.S. state and one of several Brown is scheduled to secure while here.

BEIJING -- The local media have given it a name: "Beijing Ke," or the Beijing Cough, defined by the China Daily as "a bout of persistent dry cough or throat tickle because of Beijing's poor air quality. " Earlier this year, the local air-quality reading was so bad that citizens were warned to stay in doors for days on end. The international media called it the "Airpocolypse. " For Beijing's 20 million residents, pollution has become a way of life. Even on the relatively good air-quality days, such as the ones that cold winds have brought here this week, locals take precautions.

Researchers have linked air pollution and birth defects among pregnant women in the San Joaquin Valley, according to a study by Stanford University School of Medicine. The study looked at women between 1997 and 2006, including 806 whose pregnancies were impacted by birth defects and 849 not impacted. Researchers determined that the women who spent their early weeks of pregnancy living in areas with worse air pollution had a higher risk of having a birth defect in their babies.

WASHINGTON -- President Obama is expected Monday to name Massachusetts Institute of Technology nuclear physicist Ernest J. Moniz to lead the Energy Department, and the Environmental Protection Agency's clean-air chief, Gina McCarthy, to run that agency, according to a White House official.   The nomination of McCarthy, 58, is likely to draw fire from congressional Republicans who, over the last four years, have attacked the EPA's new regulations to cut air pollution, including emissions of greenhouse gases, as job-killing government overreach.

Meat is murder, as the singer and animal activist Morrissey reminded us earlier this week. It's also incredibly bad for the environment. Livestock is among the causes of greenhouse gas emissions , which is responsible for global warming. (Watch this incredible video , and if you only have a minute to spare, fast forward to the 9-minute mark.) If that's not bad enough, a new study from the Air Quality Research Center at UC Davis shows that grilling is responsible for toxic air pollution.

Air pollution caused by hydraulic fracturing, a controversial oil and gas drilling method, may contribute to “acute and chronic health problems for those living near natural gas drilling sites,” according to a new study from the  Colorado School of Public Health . The study , based on three years of monitoring at Colorado sites, found a number of “potentially toxic petroleum hydrocarbons in the air near the wells including benzene, ethylbenzene,...

BEIJING -- Few have experienced more rapid success in China than the auto industry, which has doubled its volume sales in just the last four years. But as anger simmers over the country's air pollution, fingers are increasingly pointing at the millions of new cars clogging Chinese roads. Following a weekend in which the country experienced some of its worst smog on record , the Ministry of Environmental Protection pledged Monday to reduce vehicle emissions, the source of about a quarter of China's air pollution.

When UC Davis scientists collected air pollution particles in Fresno and then exposed laboratory mice to them, they found that one of the most toxic sources was the backyard grill. Along with particles from vehicle and wood-burning emissions, particulates from residential cooking had the greatest measurable impacts on mice lung function.   “That was like, wow!,” said Anthony Wexler, the study's coauthor and director of the Air Quality Research Center at UC Davis. “It's not that you're cooking; it's how you're cooking.

NORTH POLE, Alaska - In Krystal Francesco's neighborhood, known here as the "rectangle of death," the air pollution recently was so thick she could hardly see across the street. Wood stoves were cranking all over town - it was 40 below zero - and she had to take her daughter to the emergency room. "She's crying because she can't breathe, and I can just see her stomach rapidly going in and out. Sometimes, she's coughing to the point of throwing up," Francesco said of her 2½-year-old daughter, Kalli, who uses two different inhalers.