"It's tough," Casandra said, "especially when you're involved in sports. It's hard to take in a deep breath, and your lungs feel like they're 10 times smaller."
She added, "You want to work hard, but you can't. You can't breathe."
Major ripple effects
The effects of nitrogen pollution combined with climate change aren't just an issue for humans. Scientists at the Woods Hole Research Center say excess nitrogen can wreak havoc on the environment, causing damaging ripple effects.
What goes up must eventually come down -- often in the form of acid rain. Excess nitrogen corrodes buildings, kills plant species and can harm sensitive crops. Nitrogen that seeps into the water supply causes ocean acidification and destroys coral reefs, a natural barrier that prevents damage to coastal property. It also reduces the oxygen level within the water, asphyxiating marine life.
"Once in the environment, nitrogen cascades from one negative environmental impact to another," according to the study.
The United States has come a long way in reducing nitrogen emissions, mainly by increasing motor vehicle engine standards and regulating power plants, but there's a lot more that needs to be done, Davidson said. Nitrogen reduction has to be a large-scale affair in order to protect the nation's health and its natural resources, he added.
Yesterday, Casandra played a volleyball game -- Linden High School against Amador High School. The match was intense, and by the end of it, she was out of breath. Her mother, sitting on the sidelines, watched her daughter closely for signs of distress.
Outside the gym, ozone concentrations in the Central Valley continued to increase, reaching levels unsafe for people in sensitive groups like Casandra.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500