Sifting through the burnt rubble and cleaning brings health risks to Maui residents and responders.
"The soil is now contaminated. The water is contaminated where the harbor is, as well as the air is contaminated," says Andrew Whelton, a civil, environmental and ecological engineering professor at Purdue University.
Emissions worsen when a large fire — like the one in Maui — include items like construction materials, cars, paints and appliances.
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West Maui canceled community weekend meetings because they're worried about air quality and ash.
Hawaii's Department of Health has told Lahaina and Upper Kula in the western and central parts of the island not to drink the water.
They're also concerned about ash containing cancer-causing chemicals like lead, arsenic and asbestos. Those hazards could impact brain, lung, kidney, liver or blood functioning
"Folks who have underlying lung diseases like asthma, COPD, chronic scarring in the lungs would be more susceptible to this," says Dr. Mike Shea, pulmonologist and critical care physician with Maui Health.
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Shea is caring for patients in Maui. He says his biggest concern are those with chronic health conditions. Children and seniors are also more vulnerable.
"Some of the symptoms would be chronic cough, wheezing, shortness of breath, tightness in the chest, burning in the chest," he said.
On a press call Friday, FEMA said it and the EPA are working to test drinking water. Until then, for the people living there, everything from brushing their teeth to laundry must be done with bottled water.