BOULDER COUNTY, Colo.— The level of chemicals measured in spared homes near the Marshall Fire burn area do not pose an immediate health risk, but residents should still use protective measures, according to the Colorado Department of Public Health and Environment.
Fires leave chemicals behind in ash, soot and smoke, and the CDPHE said that could impact homes' furniture, walls, floors and other surfaces.
Kristy Richardson, state toxicologist at the CDPHE, said she understands residents in the area may be worried about those chemicals in their home.
“We want to reassure you that so far the levels of chemicals seen in these measurements do not reflect an immediate health risk," she said. "We do need more information about how long benzene and other chemicals might stay at these levels to evaluate the potential for long-term health impacts.”
These findings come from a University of Colorado Boulder research team that started conducting indoor air sampling for volatile organic compounds in a home that was severely impacted by the Marshall Fire's smoke. The testing occurred about a week after the blaze.
"Preliminary results show that the level of benzene in that home is higher than outdoors, but the indoor measurements have consistently been below the short-term or acute health guideline value of 9 parts per billion for benzene," the CDPHE reported. "When windows were opened to improve ventilation, the levels of chemicals went down significantly, but rose again when windows were closed."
READ MORE: All Denver7 coverage of the Marshall Fire
The team said it will continue to monitor the air in that home, and will then analyze the data from this home, plus a limited number of other homes that were impacted on a smaller scale. CU said this sampling will help them understand how long the levels of chemicals last and what can help reduce exposure.
Chemicals will continue to release into the affected home in the upcoming days and weeks, but will decrease over time, the CDPHE said.
Residents can speed the process up by cleaning their homes and using precautions to reduce their exposure. The CDPHE said that can include the following:
- Wear a well-fitted NIOSH-certified mask or respirator (such as an N95 mask or more protective respirator)
- Wear gloves, long-sleeved shirts, long pants, shoes and socks to avoid skin contact with ash or debris. If you get ash on your skin, in your eyes, or in your mouth, wash it off as soon as you can
- Avoid cleanup activities if you have heart or lung disease (including asthma), are an older adult, or are pregnant
- Keep children and pets away from ash and cleanup activities
- Air out your indoor spaces by opening windows and doors when possible and after cleaning out any ash and debris
- Use air cleaners with HEPA filters for particles and activated carbon filters for volatile organic compounds such as benzene
- Deep clean the surfaces of your home
- Keep air cleaners on until the smells go away
- Do not use ozone generators in homes if anybody is staying in the home. Ozone is toxic to breathe, and using one of these devices in the home can create a potential health risk. High ozone levels also can damage plants and materials such as paints, rubber, other natural materials, electrical wire coatings, fabrics, and artwork
- If you do use an ozone generator in an empty residence, thoroughly air out the space for at least four hours before re-entering
- Vacuum floors/carpet/rugs, drapes, and furniture using HEPA-type vacuum cleaner, or steam clean these surfaces
- Avoid doing anything that can stir up particles, such as dry sweeping and dusting. Before sweeping hard surfaces, mist them with water to keep dust down
- Do not use harsh chemical cleaners or vinegar as they can react with chemicals in the ash. Soap and water are adequate to clean ash from hard surfaces
If you start cleaning your home but notice concerning symptoms — such as repeated coughing, shortness of breath or difficulty breathing, wheezing, chest tightness or pain, palpitations, headaches, and nausea or unusual fatigue or lightheadedness — leave the home and contact your healthcare provider. Those symptoms may be related to exposure to ash or soot. The symptoms could also indicate an infection of COVID-19, the CPDHE said.
To learn more about air quality after a fire in an indoor space, click here.
Earlier this month, the Boulder County Public Health released guidance on what people should consider when spending time outside near where the fire burned.
