Officials with The Ride to Conquer Cancer say that because of extremely poor air quality, they are cancelling Day Two of the event.

The organization tweeted the following information on Saturday afternoon:

All riders are being told to come back to the starting line and efforts are being made to help riders who need assistance to get back to Canada Olympic Park.

The organization says that all bikes and gear will be gathered at COP and can be picked up later on Saturday as well as on Sunday from 7:00 a.m. to 7:00 p.m.

Just over 1,600 riders started the race on Saturday morning that would have taken them 200 km to the halfway point in Sundre, but air quality concerns have made an overnight camping stay unsafe, according to officials.

The decision to end the race was a bitter pill to swallow for many of the riders, but they understood that health does come first.

"It was the right call, but it's just disappointing that we didn't get to do the entire ride," said Alex Marin.

"It's pretty disappointing, but I can see why they called it off because it is pretty polluted out there, especially when you got in the woods," said Mitch Penny.

Race staffs says they had been monitoring the air quality in the days leading up to the event and were expecting things to be a lot better.

"After about an hour and a half into the race, there was a little shift in wind direction and everything changed," said George Andrews.

He says that all the money from the race will still come in and will be well spent to support cancer research and patients.

Environment Canada has had a special air quality statement in place since Wednesday and the AQHI currently sits at 10 in Calgary.

Anyone with further concerns is asked to contact race officials.

This year's race raised $8.12M for cancer research and in the 10 years since the first ride, over $74M has been raised.