Air and Water Quality Advisory – Eaton Canyon Fire Response

Last updated: April 2025

The Eaton Canyon Fire has raised serious, ongoing concerns about environmental health in Altadena and surrounding communities. Recent Caltech research and expanded monitoring by AQMD and public health agencies confirm that hazardous materials—particularly lead, VOCs, and particulates—have been widely dispersed. This page presents the latest facts, safety protocols, and a comprehensive Q&A to guide you and your family.

What’s New and Urgent

  • Elevated levels of lead, cadmium, and arsenic have been detected in indoor dust, outdoor ash, and soil samples up to 7 miles from the fire.

  • Mobile and stationary air quality monitoring is now active in areas downwind of the burn zones.

  • Tap water remains safe based on current testing, but vigilance is advised—especially with private wells or post-fire plumbing.

South Coast AQMD Monitoring Phases

Stage One: Mobile Monitoring

  • Duration: Four weeks

  • Focus: Real-time detection of VOCs and heavy metals using mobile labs.

  • Goal: Identify toxic hotspots and determine placement of stationary monitors.

Stage Two: Stationary Monitoring

  • Locations: Based on mobile results, community risk, wind, and proximity to schools and homes.

  • Substances Measured:

    • PM2.5 / PM10

    • Lead, arsenic, cadmium

    • Asbestos

    • Volatile Organic Compounds (VOCs)

View updates and maps: aqmd.gov/lawildfires

Air Quality Index (AQI): What It Tells You & What It Doesn’t

AQI does not measure heavy metals, VOCs, or persistent toxic ash particles. Rely also on community-specific updates and EPA/Caltech monitoring.

Ash, Smoke & Toxic Exposure Risks

  • Lead levels in urban fire ash exceeded 300 μg/g in many locations​.

  • Ash deposits extended 5+ miles southwest, including Pasadena, Highland Park, and Sierra Madre.

  • No asbestos was found in outdoor street-collected ash samples​.

  • Cleaning debris without PPE or wet methods can re-aerosolize toxic metals.

Water Safety Advisory

Current Status

  • Tap water from 52 homes tested safe; all samples were below EPA lead limits​.

  • No evidence of toxic metals entering municipal water systems to date.

  • Wells and heat-damaged plumbing may still pose risk.

Risks to Watch

  • Plastic pipes may leach benzene or other VOCs if exposed to high heat.

  • Backflow from burned homes can introduce contaminants into home plumbing.

  • Private well users must test independently before use.

Recommendations

If You Smell Smoke Indoors

  • Use a HEPA air purifier.

  • Seal gaps with damp towels under doors.

  • Ventilate only once AQI improves.

For Indoor Air Safety

  • Install HEPA or MERV-13+ filters in HVAC systems.

  • Avoid vacuuming ash without HEPA filter units.

  • Do not use swamp coolers or fans that pull air from outdoors.

For Outdoor Air Safety

  • Avoid exercising or yard work when AQI > 100 or wind kicks up ash.

  • Wear N95 or P100 masks—surgical masks are not protective against fine particles or VOCs.

  • Keep windows closed even on days with low AQI if near burn zones.

Safe Water Practices

  • Use bottled water for drinking, cooking, and brushing teeth until notified otherwise.

  • Do not use well water until tested by a certified lab.

  • Avoid boiling water to “purify” it—this does not remove VOCs like benzene.

  • Replace any melted or damaged pipes or tanks—especially plastic components.

Air & Water Quality Q&A (Expanded)

Air Quality & Indoor Safety

Q: How reliable is the AQI?
A: AQI is a helpful baseline but doesn’t reflect metal or VOC exposure. Combine it with local data from AQMD and Caltech Phoenix Project.

Q: Are HEPA filters effective against fire-related toxins?
A: Yes, for PM2.5, PM10, and some ash particles. They do not filter VOCs or gases, so combine with activated carbon filters for added protection.

Q: What about my HVAC system?
A: Use MERV-13 or higher filters and close outside air intakes. Consider adding portable purifiers indoors.

Q: Is outdoor play safe for kids?
A: Not if AQI > 100 or if ash has recently settled. Lead can be inhaled as dust or ingested from contaminated surfaces.

Q: How long will air hazards last?
A: Heavy metals persist for months, especially indoors or in sheltered outdoor areas. Monitor remediation progress and recheck air quality post-cleanup.

Water Safety & Use

Q: Is my water safe if it tastes normal?
A: Taste is not a reliable indicator. Use only water confirmed safe by Kinneloa Irrigation District or Lincoln Avenue Water Company.

Q: Can I use water for showering or cleaning?
A: If water is officially declared unsafe, avoid contact entirely—VOCs can be absorbed through the skin or inhaled.

Q: Do whole-house filters remove toxins?
A: Most do not remove benzene, lead, or arsenic. Use certified NSF/ANSI filters or seek expert testing.

Q: What about water for pets?
A: Use bottled or pre-tested water. Pets are also vulnerable to VOCs and lead.

Q: Should I flush my plumbing after the fire?
A: Yes, especially if power/water was disrupted. Consider testing water from the tap, not just the source.

Schools, Parks & Public Spaces

Q: Are schools safe for my kids?
A: Only if they have implemented air filtration and regular surface cleaning. Parents should advocate for:

  • HEPA filtration in classrooms.

  • Dust/wipe testing.

  • Soil testing in play areas.

Q: Is it safe to hike or visit parks near the fire zone?
A: Not yet. Soil and air contaminants may persist. Avoid high-traffic trails and dusty areas until testing clears them.

Where to Stay Updated

  • Air Monitoring Results: aqmd.gov/lawildfires

  • Caltech Phoenix Project: scienceexchange.caltech.edu/fires

  • L.A. County Public Health Soil/Water Testing Town Hall: YouTube Recording

  • Kinneloa & Lincoln Ave Water Quality Notices: Check provider sites or call.

Resources for Residents

For assistance and further information, residents can utilize the following resources: