Currently, Lake Tahoe’s location is the poorest place for wildfire smoke as it is situated downwind from the Caldor Fire.

The Reno Tahoe region and the central Sierra Nevada were said by the air quality officials to have the most toxic air in entire North America.

A southwesterly wind has been blowing a massive cloud of smoke from the Caldor Fire immediately to the Lake Tahoe basin since Friday. It is wrapping the region with toxic, thick air that surpasses the hazardous classification according to the Air Quality Index.

Readings on AirNow on Monday morning said a 620 AQI in Tahoe City, which exceeded the 500-mark and therefore tagged as “beyond index.”

 “Anything beyond 500, there isn’t really a number that can be calculated,” Washoe County Health District’s air quality specialist Brendan Schnieder, said. “It’s really 500-plus. It’s the worst it can get.”

The air is already labeled as “hazardous” when the Air Quality Index surpasses 300. AirNow calls it a “health warning of emergency conditions” that affects everyone. 

“Everyone should avoid outdoor activity,” Schnieder said. “And even if you’re inside your home, you should be doing light activity. It can cause a variety of health issues.”

A broad range of health concerns arise due to wildfire smoke, the Environmental Protection Agency said. Taking in toxic air can leave the lungs and eyes irritated. It can trigger asthma and heart failure as it lessens the function of the lungs. It can also be the reason for premature death. Among the vulnerable groups are children, pregnant women, and the elderly, EPA said.

Several residents in Lake Tahoe and Reno said that the current wildfire smoke is the worst they ever suffered. A resident of Reno since 2004, Schnieder said that the mountains were covered for a long period of time.

Another resident Ed Miller from Tahoe’s West Shore, in Tahoma, recalls how the current wildfire smoke resembles the one in 2013 during the Rim Fire in Yosemite.

“It’s changed our lives,” Miller exclaimed. “Our everyday activities. For example, we used to take our puppy swimming almost every day in Homewood. And we’re not doing that anymore. We just canceled an appointment in Truckee, because we don’t want to go out. It’s very gloomy. It’s depressing. It’s anxiety producing.”

Across North America, Lake Tahoe and parts of northern California as well as northern Nevada post worst measurements on the Air Quality Index.

According to Schiender, other areas in North America are having healthier and cleaner air as compared to Lake Tahoe, Carson Valley, Sierra Nevada, and the Reno area.

Record-breaking air quality was even logged for Reno on Sunday, Schnieder said, as the 24-hour average reached 251. Usually, Reno’s 24-hour average falls at around 25 to 30, SFGate reported.

“Since 2013, we’ve had wildfire smoke impacts every summer,” Schnieder said. “2018 was notable. 2020 was even worse. And now 2021 is even worse than 2020. So it does appear to be this sort of pattern of more wildfire smoke-affected days. But also, those wildfire smoke-affected days are worse than they have ever been.”