SAN FRANCISCO (CBS SF) – The inaugural Virgin Sport Festival of Fitness that was scheduled for this weekend in San Francisco has been canceled because of air quality problems caused by the North Bay wildfires.

The events Saturday and Sunday, which were going to include a one-mile race at Twin Peaks on Saturday and a half-marathon on Sunday, will not go forward.

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“Air quality is a major concern,” Virgin Sport CEO Mary Wittenberg said in a statement. “Another priority for us is making sure that city and local officials, as well as first responders, have no distractions in doing what they need to do to help affected communities manage this situation.”

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Wittenberg said, “This was a big decision, given that this was our inaugural event and many stakeholders, including volunteers and of course the athletic community, worked hard to make it a reality. It’s also the right and necessary thing to do, for the sake of everyone’s health and safety.”

Entry fees will be refunded to all participants. Virgin Sport is also making a $25,000 donation to the American Red Cross.

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