The department says it has been re-evaluating naphthalene, an active ingredient in mothballs and moth flakes used to control moths and larvae that eat clothes.
The labelling changes will include a reduction in the maximum application rate and directions to store the products well sealed and out of the reach of children and pets.
The new labelling will also instruct consumers to use mothballs and moth flakes in well-ventilated areas and in indoor settings only.
The department says the new packaging should be aimed at discouraging children from accidentally eating loose mothballs and to minimize the escape of vapours while the product is being stored.
Exposure to naphthalene vapours can cause headaches, nausea, dizziness and vomiting, and ingestion of mothballs or over-exposure to mothball-treated fabrics can lead to hemolytic anemia, the abnormal breakdown of red blood cells.