Carbon Monoxide Levels in Lynwood Puzzle Experts : Environment: City violates standards more often than any area in the nation. The cause eludes researchers.

Carbon Monoxide Central lies at latitude 33 degrees, 55 minutes, 20 seconds and longitude 118 degrees, 12 minutes, 42 seconds--better known as 11220 Long Beach Blvd. in the working-class suburb of Lynwood.

The storefront at that address bears no identifying sign. Grime coats the drawn window blinds; an empty bird’s nest tops the door. Inside, electronic instruments deliver data to a far-off computer and on the roof, a weather vane twirls, checking wind speed and direction.

This spot violates federal carbon monoxide standards more frequently than any other in the nation. The store is a monitoring station run by the South Coast Air Quality Management District where the U.S. limit--an eight-hour average of 9.4 parts of carbon monoxide per million parts of air--was exceeded 47 times in 1990. The country’s runner-up, nearby Hawthorne, surpassed the limit only 11 times.

Concentrations of carbon monoxide--a colorless, odorless gas that steals oxygen from blood-- started dropping nationwide in the mid-1970s. Although Lynwood has followed that pattern, levels there remain consistently higher than in surrounding territory.

For more than two years, scientists from all over the West, recruited by the state Air Resources Board, have been trying to figure out why.

They have used tethered weather balloons, a Pontiac equipped with a carbon monoxide scanner and a roadside sensing device that measures emissions from passing cars.

They have pondered questions of chemistry, meteorology, sociology and traffic.

They are troubled by their findings. “I probably would personally worry about living there,” said physicist Robert C. Nininger, who headed the research team for a Monrovia consulting firm that conducted several Lynwood experiments.

Like a bully cutting in for a dance, carbon monoxide shoves aside oxygen that would otherwise attach to hemoglobin for a ride through the bloodstream. Medical researchers have linked oxygen shortages to coronary artery disease. Some also speculate that pregnant women exposed to carbon monoxide may be more likely to bear children with low birth weights, although few studies have been done.

The federal standard is the maximum amount of carbon monoxide deemed safe for the most vulnerable--people such as Lynwood’s mayor and the head of the local chamber of commerce, both multiple-bypass veterans.

Adding in daily exposures to car exhaust, cigarette smoke, kerosene space heaters and gasoline-powered lawn mowers, “people near that monitor (station) are actually exposed to even higher concentrations,” said Steven Colome, an environmental health consultant who has studied the effect of carbon monoxide on heart patients. “Yeah, I would have some concern.”

In probing the mysteries of Lynwood, researchers are exploring a form of foul air that has not received as much attention as the region’s notorious smog. Carbon monoxide is a very different kind of pollutant.

Smog’s prime time runs from May to October because sunlight, which plays a central role in its formation, is twice as strong in the summer as in the winter. Carbon monoxide is a winter phenomenon because cold air traps it close to the ground.

Smog’s major element, ozone, is created from many chemicals baking over time as they are borne east by the winds. The blending generally occurs quite far from the factories and exhaust pipes where the chemicals started out.

Carbon monoxide is spewed directly into the air, with no time lost to complex reactions. It becomes a problem close to the spot where it is generated. Motor vehicles are thought to be responsible for about 90% of carbon monoxide in the air.

And so it follows that smog is most dense in the Inland Empire--Lynwood’s ozone problem is relatively minor--while carbon monoxide concentrates in the western, more heavily populated parts of the Los Angeles Basin.

Why Lynwood is the worst of the worst is not so obvious. But researchers hope to have the answer by the end of the year, after one more carbon monoxide season has come and gone.

Already they speculate that causes include a fateful combination of light winds, a concentration of old, highly polluting cars and, most important, the hundreds of thousands of vehicles wending their way along commuter routes that bracket the city.

Still, riddles remain and researchers wonder if the key factor is eluding them.

At first glance, it seems clear that the culprits are cars.

The Long Beach Freeway forms Lynwood’s eastern border. The Harbor Freeway hovers to the west. Imperial Highway, a heavily traveled shortcut from the Los Angeles International Airport area, slices across Lynwood’s northern edge. Locals call it “the Imperial bottleneck.” The Artesia Freeway runs to the south.

To complicate matters, the Glenn M. Anderson Freeway--familiarly known by its former name, the Century--is being built through the center of town.

Now it is an empty stretch of concrete, but with plenty of graffiti testifying to the presence of visitors (“Smog King,” for one, has been there).

But the Anderson Freeway is scheduled to open in the fall of 1993. Despite a car-pool lane and, eventually, a light rail line in the median, the highway is expected to carry 147,000 tailpipes through Lynwood every day.

The prospect adds fuel to the debate over freeways’ impact on air quality. The Anderson’s course through Lynwood is “not going to help,” said Margaret Hoggan, an AQMD analyst.

Caltrans engineer Ralph Thunstrom believes it will. He said the freeway will divert traffic off Lynwood’s surface streets and ease congestion, leading to a reduction in the number of idling engines that emit large amounts of carbon monoxide.

Whoever is right, there is more to the Lynwood dilemma.

After all, there are plenty of freeways crisscrossing the rest of Los Angeles County, in areas where the carbon monoxide readings are not nearly so high.

But the cars traveling Lynwood’s surface streets also tend to be older and the contents of their exhausts dirtier than in other parts of the county, ARB and University of Denver researchers found.

In December, 1989, they used a roadside sensor--sort of a radar gun for pollutants--in Lynwood, the Mid-Wilshire area and Long Beach. When they detected cars with high carbon monoxide emissions, they captured the license plates on videotape and sought more details about the offenders from the Department of Motor Vehicles.

The cars measured in Lynwood had a mean age of 8.73 years, compared to 5.3 in the other two locales. Previous tests of the sensing device in Chicago found vehicles with a mean age of 5.5 years, said University of Denver chemist Donald H. Stedman.

The older cars spewed out considerably higher amounts of carbon monoxide than their newer counterparts, Stedman said. Some were built before pollution control devices were required, some have been the object of tampering and many were not well-maintained, he said.

That comes as no surprise to Charlie Redner, shop foreman for a charter bus company on Long Beach Boulevard. He has been known to pass time classifying the busy traffic by the color of its exhaust: black smoke, blue smoke, white smoke. Each bears witness to a different mechanical problem. “I saw a beauty the other day, the worst I’ve ever seen,” he said. “It looked like a ’63 Cadillac.”

There is a reason for the aging fleet in Lynwood: money, or rather, the lack of it. Lynwood is no Beverly Hills. Santiago Regis bought a 20-year-old truck for his ice cream route because it was all he could afford. “I’m my own mechanic,” he said, as he checked out the running engine while in a supplier’s lot. “I have to be, to make it.”

Air pollution is not something he thinks about much, and when he does, he accepts it as part of living in the city. “I don’t smoke, but you don’t have to smoke to get bad air in Los Angeles,” he said. “That’s just how it is.”

But adding old cars to the equation does not provide a full answer. There are plenty of old cars outside Lynwood, too.

So investigators also have looked for clues in the lay of the land and the currents of air.

In winter, the inversion layer is much lower than in summer--cold stagnant air traps pollutants at the rooftop level of a one-story house.

The inversions are even stronger in Lynwood because of slight ridgelines to the west and south. “It acts sort of like a very shallow basin,” said AQMD senior meteorologist Joseph Cassmassi.

The morning and evening winds are light, significantly slower than in Vernon, a suburb just more than six miles away. There is little to push out the carbon monoxide cloud.

That cloud tends to cover the entire city, the research team found. They had wondered if the AQMD monitor, situated on a busy street, was in a particularly sensitive spot. But 30 extra monitors and the roving Pontiac with on-board sensors determined that that was not the case.

Even that information does not complete the puzzle. The data gatherers have found two more pieces that do not easily fit.

For one thing, Lynwood’s carbon monoxide levels tend to peak twice during the day. The first is from 6 a.m. to 8 a.m., during morning rush hour. That makes sense. The second, though, is from 10 p.m. to midnight, well after the evening commute has ended.

Instruments in anchored weather balloons discovered something else that cannot be readily explained. Carbon monoxide levels were higher above the inversion layer than below.

Does Lynwood’s carbon monoxide problem stem from something besides cars? Is it coming from somewhere else?

“I don’t know right now,” said John L. Bowen, an analyst with the Desert Research Institute, part of the University of Nevada. His duty is to take the parts the various scientists are contributing and work the sum.

Meanwhile, according to the AQMD, Lynwood had two first-stage carbon monoxide alerts this winter. An alert is called when levels rise 5.6 parts per million over the standard, triggering requests for car-pooling and use of mass transit.

They were the only carbon monoxide alerts in the Los Angeles region this year.

The Lynwood Mystery

The carbon monoxide levels in Lynwood are among the worst in nation. Scientists are working to learn why. Here is some background: A Grim Picture

In terms of carbon monoxide emissions: U.S. Standard: 9.4 parts per million on average over eight hours.

Worst in Nation: In 1990, the city of Lynwood exceeded federal standard 47 times over 37 days.

Lynwood also had four carbon monoxide alerts -- when levels exceed 15 parts per million -- the only ones in California in 1990.

The Runner-Up: The city of Hawthorne, which exceeded federal standard 11 times in 10 days in 1990.

Car Trouble

Following are the number of vehicles that pass through the Lynwood area on freeways each day:

Freeways Vehicles Per Day Glenn M. Anderson 147,000* Long Beach 193,000 Harbor 219,000 Artesia 237,000

*Projected number of vehicles for freeway, formerly known as the Century, now under construction

SOURCE: Caltrans