The state Health Department and Maui County officials are advising residents to be cautious of toxic hazards and to use personal protective equipment when returning to burn sites.

“The Hawaii Department of Health advises avoiding the burn area until it is cleared of hazardous waste and structural ash,” said Diana Felton, chief of DOH’s Communicable Diseases and Public Health Nursing Division in a statement. “The burn area is hazardous — enter at your risk.”

The burn area in Lahaina includes many buildings that were constructed before 1970 and may have included these contaminants in building materials, she said. Arsenic may be present in the soil in Hawaii as it was used as an herbicide.

Maui County warns of dangerous conditions and potential exposure to toxic materials that include, but are not limited to:

>> Hazardous materials including asbestos, lead, ash, heavy metals, oils, fire retardants, pesticides, silica dust, and other hazardous materials;

>> Puncture hazards including broken pipes, exposed nails, broken glass, and damaged structural elements;

>> Explosive hazards including propane tanks and solvents;

>> Toxic airborne particles such as asbestos, silica dust and lead

>> Unstable or slippery surfaces and holes in septic systems and burn pits.

Officials recommend that children be kept away from these sites, and say children should not be near or play near areas with ash or debris. Both children and those who are pregnant are at higher risk from hazards, officials said, and should not help with clean-up efforts.

Those who can return to their properties should take the following precautions:

>> Protect yourself. Wear protective face masks, goggles, gloves, long sleeves, pants, socks and closed-toed shoes (to avoid skin contact with ash). DOH recommends a tight-fitting respirator mask. Look for the words NIOSH or N95 printed on the mask.

>> Protect others. DOH recommends changing clothes and showering before being in contact with sensitive groups like children, pregnant people, those who have asthma or COPD, and kupuna.

>> Beware of ash. It may cause irritation of the skin, nose, and throat, and may cause coughing. Ash and dust (particularly from burned buildings) may contain toxic and cancer-causing chemicals including asbestos, arsenic, and lead. Avoid washing ash into storm drains. Do not use vacuums or leaf blowers which will push more ash into the air.

>> Beware of ash pits, or holes full of hot ashes created by burned trees and stumps. Falling into ash pits or landing in them can cause serious burns.

>> Do not eat in or around any burned areas or food that may have been exposed to ash, dust, or smoke. Wash and rinse all fruit and vegetables that may have been exposed.

>> Clean all recovered items thoroughly with soap and safe/clean water. Smoke-damaged properties and objects may need professional cleaning if heavily exposed or damaged.

>> Contact a doctor as soon as possible if you experience any health problems.

An unsafe drinking water advisory remains in effect for Lahaina and Upper Kula. Maui County officials say tap water continues to be unsafe in affected areas detailed on their maps, and that bottled water should be used for all drinking, for brushing teeth, and ice and food preparation.

More information is available at health.hawaii.gov/mauiwildfires.