County’s Air in 2000 Cleanest in 3 Decades

Ventura County residents breathed cleaner air in 2000 than in the past three decades as heavy smog days plummeted to only one for the entire year, according to a report on air pollution released Friday.

The drop in high smog days, from a 1974 peak of 122, comes even as the county’s population has doubled since monitoring for smog and its hazardous ozone component began in 1973, said officials with the Ventura County Air Pollution Control District, which compiled the report.

“Air quality in Ventura County has improved tremendously,” said Richard Baldwin, executive officer of the air pollution control district. “The year 2000 is the best on record for the one-hour federal ozone standard.”

The one day this year when residents breathed significantly dirty air occurred in Simi Valley--the county’s smog hot spot--in September during a heat wave, said Kent Field, district meteorologist.

Exceeding the one-hour federal ozone standard means that for at least 60 minutes on a given day, ozone concentrations averaged more than 0.12 parts per million. Levels that high can be detrimental to health, particularly in children or people with asthma, officials said.

Cool, breezy weather caused by coastal low-pressure systems dominated this year and helped blow away smog in Ventura County, which nevertheless remains on the Environmental Protection Agency’s list of areas with a severe smog problem.

“We are experiencing long-term, significant improvement in our air quality, both in the frequency and the magnitude of the smoggiest days,” said Doug Tubbs, manager of the district’s monitoring and technical services division.

The return of cleaner air in Ventura County follows a statewide trend “that’s largely due to cleaner cars each year and a reduction in diesel fuel emissions,” said Jerry Martin, a spokesman for the California Air Resources Board.

While the report is encouraging, Ventura County still has a long way to go before meeting many of the EPA’s standards.

To comply with federal standards, air quality in the county must not exceed the one-hour ozone standard more than three times in three consecutive years, officials said.

Ozone, which makes up about 95% of Southern California’s smog, is formed when hydrocarbons from vehicle emissions react with sunlight. It can cause severe respiratory problems and lung damage.

Ventura County also monitors the more stringent one-hour state standard and the federal eight-hour standard for ozone, said Barbara Page, a district spokeswoman.

The state standard of 0.09 parts per million was exceeded on 37 days this year. The federal eight-hour standard, which requires that ozone levels average 0.08 parts per million over an eight-hour period, was topped on 29 days.

The eight-hour federal standard, which the EPA is still defending in court challenges, is intended to protect people living and working in lower levels of ozone but facing constant exposure to the pollutant, Martin said.

“The feeling is that long-term exposure can be very detrimental to public health,” Martin said.

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SMOG DAYS

Number of days Ventura County’s air exceeded federal health standards in the past five years:

1995: 23

1996: 17

1997: 2

1998: 5

1999: 2

2000: 1

Source: Ventura County Air Pollution Control District