Mildew odor in stuffed animals is caused by the growth of microscopic fungi, such as Aspergillus or Penicillium species, which thrive in damp conditions. These organisms metabolize organic material within the fabric and stuffing, releasing volatile organic compounds (VOCs) that produce the characteristic musty smell. Stuffed animals are made of porous materials that easily trap moisture, and when combined with poor ventilation, this creates the perfect environment for fungal growth. Eliminating the smell requires a systematic approach to remove the fungi and ensure the toy is completely dry.
Assessing the Stuffed Animal’s Washability
Before cleaning, check the manufacturer’s care tag for specific washing instructions, which dictate whether the toy can withstand machine agitation. Items containing electronic components, such as battery packs, music boxes, or internal wiring, should never be submerged in water and require a surface-only cleaning method. Fragile elements, including glued-on plastic eyes, delicate trims, or very old fabrics, also necessitate avoiding the washing machine. For toys with bright or dark colors, perform a spot test by dabbing a small, inconspicuous area with a damp, soapy cloth to ensure the dyes do not bleed before proceeding with a full wash.
Step-by-Step Odor Elimination
Machine Washing
For durable stuffed animals, use a mesh laundry bag to protect the toy from friction and agitation during the wash cycle. Select the gentle or delicate cycle setting and use cold water to prevent shrinkage and damage to synthetic fibers. Use a small amount of mild, enzyme-based laundry detergent to break down the organic residue that feeds the fungi.
Hand Washing
If the toy is too fragile for a machine, hand washing is the safer alternative. Submerge the item in cool water mixed with a small amount of mild soap. Gently squeeze the toy repeatedly to push the soapy water through the dense stuffing, ensuring the solution reaches the odor source. Rinse the toy thoroughly under running water until no suds remain.
Baking Soda Treatment
Stubborn odors may require a natural deodorizer like baking soda, which absorbs odor molecules. Place the completely dry stuffed animal in a large, sealable plastic bag with about half a cup of baking soda. Shake the bag gently to coat the exterior, then allow the toy to sit undisturbed for at least 24 hours to maximize absorption. Remove the toy and use a soft brush or a vacuum cleaner hose attachment to remove all traces of the powder.
Safe and Thorough Drying
Thorough drying is important, as any residual moisture allows dormant mildew spores to reactivate. Air drying is the preferred method and should be done in an area with excellent air circulation, such as near a fan or dehumidifier, to accelerate evaporation. Sunlight acts as a natural disinfectant because ultraviolet (UV) radiation helps kill remaining mold spores on the fabric surface.
Prolonged exposure to direct sunlight can cause fading, especially on dark or brightly colored fabrics, so limit sun exposure to a few hours. If using a machine dryer, select only the lowest heat setting or the air-only cycle to prevent damage. High heat can melt synthetic materials like polyester fur or stuffing, causing the toy to become misshapen or stiff. The stuffed animal must be 100% dry, including the dense stuffing deep inside, before it is stored or returned to use.
Preventing Future Mildew Smells
Long-term storage requires maintaining a dry environment to inhibit fungal growth. Avoid storing stuffed animals in areas prone to high humidity, such as unfinished basements, damp closets, or unventilated attics. Use breathable containers like cotton bags or ventilated plastic bins instead of sealed plastic bags, which trap moisture and restrict airflow.
Maintaining a relative humidity level below 50% in storage areas prevents mold proliferation. Give the toys a periodic “sun bath” for an hour or two to remove latent moisture absorbed from the air. If a stuffed animal becomes wet from a spill or rain, dry it immediately using a fan or a low-heat dryer cycle to prevent mildew.