San Mateo neighborhood blocked off for hours due to mysterious gray dust

JACKSONVILLE, Fla. — The Jacksonville Fire Rescue Department now knows the identity of the mysterious dust that worried some neighbors in the San Mateo neighborhood on Friday: humic powder.

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According to JFRD, the owner of Humic Growth Solutions contacted officials and helped them identify the dust. The owner said his company had a system malfunction that caused the dust to get loose. The wind then may have carried the dust elsewhere.

The San Matero neighborhood was blocked off by police while officials worked to identify the substance.

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Captain Eric Prosswimmer said the owner saved JFRD and the hazmat team hours of work by coming out to the neighborhood and helping them.

According to JFRD, the dust is a little acidic. If it gets on your skin, you should wash it off with mild soap and water. If you get it in your mouth or eyes, flush it with water.

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