Thiabendazole is a fungicide approved for use in a variety of crops in a number of methods: as a pre-planting treatment for soybean, wheat, and sweet potatoes; on growing mushrooms; and as a post-harvest dip or spray for a number of fruits and vegetables. This spray is typically applied at the same time as wax coating of produce occurs.
In animal studies, thiabendazole is carcinogenic and damaging to normal liver and thyroid function. Thiabendazole is assessed as safe to humans at the levels expected from a typical diet (and residue levels are, as a standard, restricted to levels well below those which cause negative effects in studies).
Thiabendazole is approved in the US but not in the EU, Australia, or New Zealand.
Residual on soybeans, wheat, and sweet potatoes, mushrooms, citrus, apples, pears, bananas, mangos, papaya, plantain, carrots, avocados, peas, potatoes
EPA
UK Government
Australian Government
TBZ, Tiabendazole