Unless your loss was declared to be the result of a federally declared disaster, your mold remediation expenses are not deductible. Per the instructions for SCH A line 15 at https://www.irs.gov/pub/irs-pdf/i1040sca.pdf on page A-13:

You can only deduct personal casualty and theft losses resulting from a fed-erally declared disaster to the extent that:

1.The amount of each separate casualty or theft loss is more than $100, and

2.The total amount of all losses during the year (reduced by the $100 limit discussed in (1)) is more than 10% of the amount on Form 1040 or 1040-SR, line 8b

Losses You Can Deduct

For tax years 2018 through 2025, if you are an individual, losses of personal-use property from fire, storm, shipwreck, or other casualty, or theft are deductible only if the loss is attributable to a federally declared disaster (federal casualty loss). See Pub. 547 for more information.

https://www.irs.gov/instructions/i4684