Warfarin
WASTE ANESTHETIC GASES
Water
Weeping fig
Welding fumes (not otherwise specified)
West Indian sandalwood oil
West Nile virus
Western red cedar, dust
Wheat flour
Wheat weevil
Whey
White mineral oil
Wolframite
Wollastonite
Wood dust, all soft and hard woods
Wright's stain
Wucheria bancrofti