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Program Focuses On Tracking Air Pollution At US-Mexico Border

Reported by Nicholas Mcvicker

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San Ysidro residents may know soon whether the heavy traffic that moves through their community is carrying an air pollution risk.

Four-year-old Bruno Lopez grabs a crossbar on a playground structure on San Ysidro’s Howard Lane Park. He swings out, lets go of the bar and slides down to the ground. Moments later he’s on top of the slide, ready for more.

Rudy Lopez smiles as his son runs around the play structures. But dad is also keeping a close eye on his son. That’s because Bruno suffers from asthma.

“He was about a year old when he first started having respiratory issues. Around two-and-a-half, he came down with pneumonia, asthma-related pneumonia,” Rudy Lopez said.

The California Department of Health says asthma afflicts more than 400,000 San Diego County residents. That’s more than one in 10 people, and the rates are higher in congested urban neighborhoods like San Ysidro.

“The doctors told us if we could get it under control now, it wouldn’t be a permanent condition. And that’s when we really wanted to see what can we do to help control it,” Rudy Lopez said.

Exposure to smoking and air pollution are two primary causes of asthma.

Lopez doesn’t smoke, so that got him thinking about San Ysidro.

Even here at the expansive Howard Lane Park, traffic is hard to escape. The Interstate 905 and a heavily traveled surface street border two sides of the green space.

“I hadn’t really thought about it before he started having asthma, but now that we look around, we see we are so close to one of the biggest vehicle ports of entry in the world. We have three freeways here in San Ysidro, one of which carries considerable truck traffic,” Lopez said.

Air pollution data is hard to find

San Ysidro is a community with around 22,000 residents. Most of the homes are rentals. The tightly clustered houses are squeezed in between the international border and the freeways that funnel traffic north and south.

The California Environmental Protection Agency and the state Office of Environmental Health Hazard Assessment track pollution, especially in economically challenged areas like San Ysidro. But getting good air pollution data near the border is a problem.

Photo by Nicholas McVicker

Traffic at the U.S.-Mexico border crossing at San Ysidro, Dec. 19, 2016.

“We are trying to get a better measurement of that pollution, and as you say, pollution doesn’t respect borders, and it's something we have to do a better job in terms of gathering data around the border,” said Alex Barnum, CalEPA spokesman.

That’s important because the state’s analysis identifies priorities for funding. If there’s a pollution problem, the region could get help building parks or more bikeways.

And while cross-border pollution isn’t well measured, gathering data north of the U.S.-Mexico border isn’t especially effective either. San Diego’s Air Pollution Control District did have a pollution monitor at the border, but its findings were inconclusive.

“There were some slightly elevated levels of particulate matter from diesel exhaust, but nothing out of the ordinary,” said Bob Kard, San Diego’s air pollution control officer.

The pollution monitor isn’t currently taking measurements. It was taken down because of renovations to the Port of Entry. But it remains clear that 70 percent of the county’s air pollution comes from cars and trucks. The lack of a monitor doesn’t change that.

“There are increased pollutant levels,” Kard said. “And frankly, if you’re by the road, and a diesel truck comes by, and it is smoking, and you’re downwind of it, you’re inhaling a lot more than even we would be recording.”

Rudy Lopez wants to know if there is a serious pollution issue in San Ysidro. He would like to see proof.

“There hasn’t been a constant monitoring of the situation. I think that’s one of the problems. There isn’t anything tangible. People say, 'You think there’s a problem, but until we monitor it, and we can show, hey these are the numbers, these are the cold hard facts,' not many people are going to pay attention to it,” Lopez said.

Answers may be coming

David Flores, a community advocate who works for Casa Familiar, stands on the roof of an old stucco church in the heart of a residential San Ysidro neighborhood. Mexico is less than a mile to the south.

Photo by Katie Schoolov

David Flores stands next an air pollution monitor in a San Ysidro neighborhood, Jan. 10, 2017.

Flores looks at somewhere else, however. He looks toward a gray metal box, big enough to put a pair of work boots inside.

“So this is the box; this is the equipment the University of Washington has developed. Really compact and in a weather-proof cover. You can hear the fan sucking up the air,” Flores said.

The air that’s drawn inside is exposed to several sensitive monitors. Flores points to the largest piece of equipment inside the box.

“This is the one that measures. [It's] taking all the data and measurements for all the different pollutants,” Flores said. “And here, each one of these represents a different pollutant: nitrous oxide, carbon monoxide, ozone and nitrogen dioxide."

The monitors take readings, and they send the data wirelessly to a computer that can analyze and interpret the findings. Jenny Quintana, a San Diego State University public health researcher, runs the pollution monitoring project.

She is working with University of Washington researchers to make sure the air pollution data is accurate and meets rigorous academic standards.

“Actual numbers are very useful,” Quintana said. “In addition, we can find potential sources of air pollution. People have speculated that the border crossing is a source. They have speculated that burning activity and vehicle emissions in Tijuana can affect communities north of the border, but there’s no actual studies and data that can be provided for that, for this community.”

Scientifically verifiable information can be used to confirm the region has air quality issues.

Accurate data

A study that used high-end monitors back in 2008 was inconclusive, but if this effort turns up hard data on pollution, that could help San Ysidro. The community could push for state and federal money to build parks and bikeways, add air filtration systems to schools and senior centers, and build affordable housing.

Quintana says that’s why she and other researchers are working with the San Diego Air Pollution Control District. The community monitors are being tested right beside the district’s significantly more expensive and sensitive equipment.

“Because the technology is up and coming — not well-developed yet, not well-vetted. But this is all part of the vetting process where they can determine whether these things truly give an accurate picture of air quality at what I call the 'microscale level' — the street level — near sources of traffic or maybe a local industry,” said Kard.

Quintana said getting it right is crucial. If the monitors are effective, they will be able to help researchers determine what’s in the air and even where it may be coming from.

“I think data accuracy, to the extent possible, is a really important focus of this study and will help inform other communities as they try to carry out these activities,” said Quintana.

The possibility that this technology could play a similar role in other neighborhoods is pushing those involved in the research to make sure this study is done right. The team will monitor the air through the summer with the hope that they can develop an easy to read web page the community can use to monitor pollution in real time.


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