In Paradise, many families are still combing through the wreckage of the 2018 Camp Fire that burned over 150,000 acres. Camille Von Kaenel of the Chico Enterprise-Record in her article "Residents still trying to understand Camp Fire contamination at standing homes" writes,

One hurdle has been getting a good understanding of the extent of possible health risks from the smoke and ash that soaked into the homes that day and the following months. There are no industry-wide recognized standards specifically regarding contamination from urban wildfire smoke and ash in homes. So in the Camp Fire areas, insurance companies and environmental health professionals have taken a sometimes uneven approach, leaving homeowners to compare notes and request the clean-up they want.

Von Kaenel interviewed UC Davis Air Quality Research Center Director Tony Wexler who commented that during this clean-up phase, a big worry should be around the ash that surrounds the homes and it constantly being tracked into the home. Ash can be a toxic substance composed of the cars, plastics and other household chemicals that burned as a result of the wildfire. Director Wexler warns families to take care in not tracking the ash into homes. 

You can read more of Von Kaenel's article online here