Santa Clara County’s worsening air quality is reflected in its failing “State of the Air” grades, according to the American Lung Association. 

With ozone levels and annual particle pollution consistently reaching unhealthy levels, the county has struggled to pass air quality assessments since 2016. 

Data from the Bay Area Air Quality Management District shows that Redwood City’s highest January ozone levels have risen by 30 points over the last 20 years, highlighting a troubling trend that experts like Michael Flagg, Principal Air Quality Specialist at the BAAQMD, continue to monitor closely.

Flagg said the agency tracks pollutant particles in the air.

“Pollutants are regulated by the Department of Health Protection Agency under the Clean Air Act, so that’s particulate matter, ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide and lead,” Flagg said. “These are the pollutants that we track over time. If we’re looking back 20 plus years, air quality has decreased since the early 2000s. What’s been happening more recently, like the last 10 years, is that concentrations generally have been fairly stable.”

Stanford Clinical Assistant Professor of Pulmonology and Critical Care Lauren Eggert said PM 2.5 particles, particles that are 2.5 micrometers in diameter and smaller, are of particular concern because they can pass through masks and handkerchiefs.

“AQI is the air quality index and that measures the levels of that 2.5 µm (micrometer) particulate matter in the air, and PM 2.5 is particulate matter that’s 2.5 µm in size,” Eggert said. “That is the small particulate matter that we worry about because it’s so small, it easily gets into the lungs. It goes through a regular surgical mask.”

Flagg also said ozone pollution poses a major health risk.

“The other main pollutant is ozone,” Flagg said. “It’s not emitted directly into the atmosphere. It’s essentially emissions from sources of air pollution, and then in the presence of sunlight and heat, they form ozone.”

Due to air pollution, California has made efforts to improve its air quality. However, Stanford Associate Professor of Pulmonary and Critical Care Medicine Peter Kao said recent wildfires have offset recent progress in reducing emissions.

“We’re having a higher frequency of wildfires in California where the sky turns orange, and the air quality can be as bad as 200 or 300,” Kao said. “There’s been simultaneous efforts over the past three decades to reduce smog by improving pollution controls on cars — that’s helped, but that has been counterbalanced by the increasing incidences of wildfires.”

Kao also said poor air quality can affect breathing and other health problems.

“Poor air can exacerbate and worsen asthma bronchitis, which is a production of large amounts of sputum asthma, wheezing, shortness of breath,” Kao said. “There are more rare diseases, some of the cardiac diseases, cardiac arrhythmia or congestive heart failure. I have some patients who are exposed to dust down in the Central Valley, and there’s fine particulate matter — not necessarily for fire smoke — that can also exacerbate their respiratory illnesses.”

Eggert said poor air not only affects healthy individuals, but it is particularly problematic for vulnerable demographics like children.

“Unfortunately, our children are the most affected because they have smaller airways, and so when they get inflamed, they’re gonna have worse symptoms,” Eggert said. “Developing lungs are at the highest risk when they have these exposures. Children that are living near major highways and roadways in LA or elsewhere develop more asthma and have worse lung function and respiratory health. There’s a lot of people now looking at the effects of these wildfires and how they may also be impacting respiratory health long-term.”

Kao said poor air quality also disproportionately affects socioeconomically disadvantaged people who may not have access to treatments.

“For the last five years, I’ve been telling many of my patients to buy an indoor air purifier and keep it in their bedroom so that they can at least sleep in a protected space where the air quality’s a little bit better,” Kao said. “Unfortunately, my poorest patients don’t have the resources to buy an air purifier.”

Flagg said in an attempt to combat this inequality, the Bay Area Air Quality Management District has been working to monitor air quality in multiple locations, especially those near refineries.

“We’re expanding our air monitoring to help better understand what’s going on,” Flagg said. “We have our core monitoring network that we operate throughout, 30 locations throughout the air district. We’re working on partnering with community-based organizations to expand access to air monitoring or access to air monitoring data in communities that live in close proximity to sources of pollution, what we call overburdened communities, which share a disproportionate amount of exposure to poor air pollution.”

To improve breathing, Eggert recommends avoiding outside activities when the AQI reaches unhealthy levels.

“In terms of how you can protect yourself on a personal level, when the air quality is poor you should avoid going outside or spending time outside and if you do, you should wear a fitting mask at least a KN or an N95 that filters 95% of that small particulate matter,” Eggert said.

Kao said a treatment he recommends is a salt water clearance.

“I’ve had firefighters be exposed to wildfire smoke, and I have recommended to them that at the end of a workday they do airway clearance therapies, which involve inhaling a mist of sterile salty water,” Kao said. “This salty water in the air tubes by osmosis pulls water across the cells and liquidizes the mucus. It was proven to be effective in patients with cystic fibrosis with very sticky glue-like mucus, but it can benefit even patients without cystic fibrosis by enhancing mucociliary clearance.”

Flagg said a bigger move to solve air quality is by targeting the source.

“The core tenets of controlling air pollution is limiting emissions,” Flagg said. “A lot of pollution also comes from cars, both passenger vehicles, heavy duty trucks and mobile source emissions that are associated with diesel engines. There have been a lot of improvements in fuel efficiency around automobiles that have definitely had a big impact on air quality. It’s not a single technology that’s going to solve the problem. It’s going to be working on a number of different ways to reduce emissions across the board for all types of different sources.”

Ultimately, Kao said protecting the air is protecting the body. 

“The body is a miracle — take nothing for granted and be grateful for your health and preserve it, don’t risk it,” Kao said. “You win the game if you live a long rewarding life. Keep your eye on the long game and honor your health, preserve your health and be grateful for it.”