2010 February 14 Sunday
Highway Pollution Speeds Artery Wall Hardening

Living near freeways is bad for your health. Of course, you get exposed to particulates when driving on freeways as well.

Researchers at the Keck School of Medicine of the University of Southern California (USC), in collaboration with international partners in Spain and Switzerland and colleagues in California, have found that exposure to air pollution accelerates the thickening of artery walls that leads to cardiovascular disease.

The study, published this week in the journal PloS ONE, is the first to link outdoor air quality and progression of atherosclerosis in humans. Researchers found that artery wall thickening among people living within 100 meters (328 feet) of a Los Angeles highway progressed twice as quickly as those who lived farther away.

This result is an argument for electric cars, tougher regulations on coal electric plants, and accelerated retirement of old belching diesel trucks that were manufactured under easier regulations.

Here's an excerpt from the full paper which you can read in full.

We examined data from five double-blind randomized trials that assessed effects of various treatments on the change in CIMT. The trials were conducted in the Los Angeles area. Spatial models and land-use data were used to estimate the home outdoor mean concentration of particulate matter up to 2.5 micrometer in diameter (PM2.5), and to classify residence by proximity to traffic-related pollution (within 100 m of highways). PM2.5 and traffic proximity were positively associated with CIMT progression. Adjusted coefficients were larger than crude associations, not sensitive to modelling specifications, and statistically significant for highway proximity while of borderline significance for PM2.5 (P = 0.08). Annual CIMT progression among those living within 100 m of a highway was accelerated (5.5 micrometers/yr [95%CI: 0.13–10.79; p = 0.04]) or more than twice the population mean progression. For PM2.5, coefficients were positive as well, reaching statistical significance in the socially disadvantaged; in subjects reporting lipid lowering treatment at baseline; among participants receiving on-trial treatments; and among the pool of four out of the five trials.

Moving more freight to trains would also cut pollution since trains use much less diesel fuel per ton of freight moved. Also, trains lend themselves to electrification. A fully electrified train system with major bottlenecks sped up would move freight with far less harm to human health both due to less pollution and fewer deaths and injuries in accidents.

By Randall Parker    2010 February 14 06:38 PM   Entry Permalink | Comments (9)
2010 January 28 Thursday
Lead A Cause Of Attention Deficit?

While genes are thought to be the biggest cause of hyperactivity and attention deficit exposure to lead might explain some cases.

ADHD, or attention-deficit/hyperactivity disorder, is among the costliest of behavioral disorders. Its combination of inattention, impulsivity and hyperactivity leads to accidental injuries, school failure, substance abuse, antisocial behavior and more. Yet despite nearly a century of study, the disorder’s roots remain mysterious. Much of modern ADHD research has focused on heritability of the condition, and indeed evidence suggests that genes may account for as much as 70 percent of hyperactivity and inattention in children. But that leaves 30 percent unexplained, so recently the focus has shifted to the environment. What is it that triggers an underlying susceptibility and changes it into a full-blown disorder? New research suggests that the culprit may be an old villain—lead—and what’s more it explains the causal pathway from exposure to disability.

Lead also lowers IQ. So it is certainly something we should keep away from children. Old lead paint and other sources of lead pollution do real harm.

The first study compared children formally diagnosed with ADHD to controls, and found that the children with the disorder had slightly higher levels of lead in their blood. This study showed a link only between blood lead and hyperactivity/impulsivity symptoms, not inattention. But a second study showed a robust link between blood lead and both parent and teacher ratings of ADHD symptoms, including both hyperactivity and attention problems. In both studies, the connection was independent of IQ, family income, race, or maternal smoking during pregnancy.

Vitamins B1 and C will help against lead.

By Randall Parker    2010 January 28 11:38 PM   Entry Permalink | Comments (1)
Air Quality Improvements Cut Child Ear Infections

An example of why we should make more strides to cut pollution.

A new study by researchers at UCLA and Brigham and Women's Hospital in Boston suggests that improvements in air quality over the past decade have resulted in fewer cases of ear infections in children.

Ear infections are one of the most common illnesses among children, with annual direct and indirect costs of $3 billion to $5 billion in the United States.

"We believe these findings, which demonstrate a direct correlation between air quality and ear infections, have both medical and political significance," said study co-author Dr. Nina Shapiro, director of pediatric otolaryngology at Mattel Children's Hospital UCLA and an associate professor of surgery at the David Geffen School of Medicine at UCLA. "The results validate the benefits of the revised Clean Air Act of 1990, which gave the Environmental Protection Agency more authority to implement and enforce regulations reducing air-pollutant emissions. It also shows that the improvements may have direct benefit on health-quality measures."

A new US Environmental Protection Agency regulation to cut back nitrogen dioxide to cut smog formation will help. A third of human-caused NO2 emissions in the US come from electric power generation. If we shifted away from oil and natural gas for electric power and used more nukes and wind we'd breathe cleaner and healthier air. Electrified rails in place of diesel trucks would also help.

By Randall Parker    2010 January 28 11:03 PM   Entry Permalink | Comments (4)
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