As many as one in 12 hospitalizations and emergency room visits by Baltimore area residents with respiratory conditions have been blamed on smog, in a new study that quantifies for the first time the health impact of ozone pollution on Baltimore and a dozen other cities across the country.
Largely because this region's ozone levels were so high, the Baltimore region ranked second -- just after Los Angeles -- in the percentage of cases linked to ozone. Released yesterday, the study estimated that locally, as many as 600 hospital admissions and nearly 2,000 emergency room visits during the summer of 1994 were caused by ground-level ozone.
Researchers from the Harvard School of Public Health analyzed hospital records from 13 metropolitan areas that consistently experience high levels of ozone during the summer, the chief component of smog. They included Dallas; Detroit; Hartford, Conn.; Houston; Milwaukee; New Haven, Conn.; New York City; Philadelphia; San Diego; St. Louis; and Washington.
"If there was one big episode [of bad-air quality], you would be outraged. It would be a real public health emergency. But the fact that it's happening over dozens of days to a subset of our population -- we don't even see it," said John D. Spengler, one of the authors, and director of Harvard's Environmental Science and Engineering Program.
Overall, Spengler and his colleagues estimated that high concentrations of ozone were linked with up to 15,000 hospital admissions and 50,000 emergency room visits in the 13 cities.
Ozone is formed when emissions from cars, power plants and even lawn mowers are "cooked" by the summer sun. Ten or 15 miles above the earth, ozone protects people from ultraviolet radiation. But close to the ground, it can cause wheezing and shortness of breath, and can worsen lung conditions. It even affects trees and plants, discoloring their leaves.
Previous studies have demonstrated a connection between smog and increased hospitalizations. This study was conducted for the American Lung Association, which is urging the U.S. Environmental Protection Agency to set a strict new ozone standard. EPA officials are reviewing the standard and expect to announce revisions by November.
The local area measured by the study includes Baltimore City and six counties: Baltimore, Anne Arundel, Carroll, Harford, Howard and Queen Anne's. So far this year, the area hasn't experienced any "bad air" days, when ozone reaches unhealthful levels. But Spengler said people are still being hurt when levels are considered "healthful."
The American Lung Association of Maryland is working with local television stations to make an "ozone map" part of each night's weather forecast during the summer.
"It's clear that ozone pollution makes people sick, and this study attempts to quantify just how many people are going to the hospital," said Glen Besa, the group's director of environmental programs. He added that more than 400,000 Marylanders suffer from respiratory illnesses such as bronchitis. "This is not a small number of people being affected."
Dr. Jonathan Samet, professor and chair of the Department of Epidemiology at the Johns Hopkins School of Public Health, cautioned that the study's numbers are only estimates.
"There's no way to know that you're exactly right. They're based on assumptions," Samet said. "We use this approach as a policy-making tool because we can't go to every location and sort of line up how big a problem we're facing."
At the Johns Hopkins Hospital Emergency Department, Dr. William Mysko said health workers are used to seeing asthmatics and others with lung conditions coming to the hospital on high smog days.
'Felt like a dishrag'
One Harford County woman knows exactly what that's like. Last June, after spending a day outside when the ozone levels were high, she found herself slumped by her bed, trying to call a friend to take her to the hospital.
"I felt like a dishrag. I couldn't even keep my head afloat," said Carol Kwiatkowski, 39. She suffers from a rare lung condition called bronchiectasis. For her, breathing can be like trying to slurp a thick, lumpy milkshake through a straw.
"I just laid there, praying and hoping that something wasn't going to happen before someone got there. It's a terrible feeling to feel that you can't breathe," she said.
Kwiatkowski said her family moved from their home near Interstate 95 and the Harbor Tunnel partly because of the smog, only to discover their new house, in Jarrettsville, is in another area where the airstream easily carries in ozone.
Cumulative cell damage
Among the healthy, the chronic effects of ozone are just beginning to be studied. Evidence from animal studies suggests that there might be cumulative cell damage, Spengler said.
But physicians advise those with lung conditions, and particularly children, whose lungs are still developing, to stay indoors on high ozone days and refrain from strenuous activity.
That's a lesson Leah Schestag and her 12-year-old daughter, Lilli, of Clarksville have struggled with. Since she developed asthma at age four, Lilli can't go to the pool or play outside when the ozone levels are high.
"It upsets me -- not just because of my daughter's problem -- but to see what has happened to our environment," Schestag said. "It upsets me that nobody is doing anything about it, despite rules and regulations to the contrary."
Pub Date: 6/21/96