Supplemental Table 1. E-Liquid Flavour Categories E-Liquid Flavour Categories (N=71) Alcoholic Beverage (Absinthe/Amaretto/Bourbon/Brandy/Champagne/Cherry Liqueur/Cognac/Daiquiri/Fuzzy Navel/Kahlua/Lemoncillo/Liqueur/Margarita/Mojito/Pina Colada/Rum/Spiced Rum/Tequila/Vodka/Whiskey/Baileys Irish Cream) Almond Nuts/Milk/Toasted/Marzipan/Candied Apple Fruit/Juice/Candied/Baked/Red/Green/Sour/Granny Smith/Spiced/Fritter Apricot Fruit/Jam Banana Berry (Acai/Blackberry/Red/Boysenberry/Elderberry/Mixed/Huckleberry) Blueberry Fruit/Jam/Syrup Blueberry muffin/cobbler/cake/pie/tart/crumble/danish Bread/Rolls/Croissant/Bagel/English Muffin/Biscuit/Scone Cake/Torte (Yellow/Vanilla/Chocolate/Lemon/Carrot/Coconut/Crumb/Coffee/Pound/Cream/Pineapple Upside Down/Red Velvet/Raspberry/Sponge/Strawberry Shortcake/Tres Leches/almond) Candied Fruit/Apple/Nuts Candy/Gum Brand (Good & Plenty/Jolly Rancher/Reeses/Pixie Sticks/Pop Rocks/Skittles/Smarties/Starburst/SweetTart/Red Hots/Gummy Candy/Swedish Fish/Lifesaver Candy/Butterfinger/Fireballs/Red Hots/Big Red/Double Mint/Fruit Stripe/Juicy Fruit) Candy/Gum Generic (Hard/Grape/Kettle Corn/Peach Ring/Peppermint/Cinnamon/Rainbow/Root Beer/Soda- Flavoured/Sour/Sprinkles/Jimmies/Taffy/Violet/Watermelon/Candy Cane/Bubble Gum/Butterscotch/Turtle/Bear Claw) Caramel (Salted/Plain) Cereal Brand (Apple Jacks/Cap'n Crunch/Froot Loops/Cinnamon Toast Crunch/Cocoa Puffs/Corn Flakes/Franken Berry/Frosted Flakes/Fruity Pebbles/Golden Grahams/Kix/Rice Krispies/Trix) Cereal Generic (Corn/Rice/Wheat/Bran/Chocolate/Fruit Flavoured/Oatmeal/Granola) Cheesecake (plain/New York Style/Strawberry/Blueberry) Cherry (Black/Wild/Maraschino/Blossom) Chocolate (Milk/Dark/White/Syrup/Hot Fudge/Fudge) Cinnamon Citrus Fruits (Lemon/Lime/Orange/Grapefruit/Clementine/Tangerine/Blood Orange/Mandarin) Cocoa (Hot Chocolate) Coconut (shredded/toasted/milk/juice/water/cream) Coffee/Cappucino/Espresso/Café au Lait/Machiatto/Mocha Cookie/Brownie/Bars/Biscotti/Macaroon (Chocolate/Chocolate Chip/Vanilla/Peanut Butter/Chocolate Mint/Snickerdoodle/Sugar/Ginger Snap/Gingerbread/Fig Newton/Macaroon/Oatmeal Raisin/Shortbread/Oreo/Brownie/Rice Krispie Treat/Biscotti) Cotton Candy/Spun Sugar Cranberry Fruit/Juice Cream, Custard, Pudding (Vanilla/Whipped/Chantilly/Bavarian/Chocolate/Crème Brulee/Blueberry/Banana/Coconut/Strawberry/Dulce de Leche) Crepes/Pancakes/Griddle Cakes/Waffles/French Toast Energy Drink (Monster, Red Bull, Extreme Energy Moose Juice) Floral (Hibiscus/Honey/Honeysuckle/Jasmine/Lavender/Perfume/Rose/Violet/Sweet Woodruff) Fruit Flavour (Fruit, Tutti Fruitti, Tropical Fruit, Exotic Fruit) Graham Cracker Grape fruit/juice/jam (Concord/White/Red) Herbal (Basil/Bergamot/Oregano/Aloe/Cactus/Prickly Pear/Eucalyptus) Ice Cream/Frozen Yogurt/Gelato/Sherbet/Sorbet Icing/Butter Cream/Glaze/Ganache/Frosting/Fondant Jam / Jelly / Preserves Juice/Soft Drink/Soda(Cola/Cherry Cola/Mtn Dew/Citrus/Cream/Root Beer/Orange/Grape/Ginger Ale/Sarsaparilla/Sprite) Licorice (Black/Red) Maple (Sugar, Syrup, Glaze) Marshmallow (Regular/Toasted/Cream/Spread Melon (Cantaloupe, Honeydew, Watermelon) Milk (Plain/Chocolate/Strawberry/Vanilla/Coffee/Buttermilk) Milk Shake/Frappe/Smoothie (Vanilla, Chocolate, Strawberry, Blueberry) Mint (Menthol/Peppermint/Spearmint/Wintergreen) Nuts (Black Walnut/Walnut/Peanut/Cashew/Pistachio/Pecan/Macademia/Lychee/Hazelnut) Other Baked Goods (Banana bread/nut bread/Gingerbread) Other Dairy (Butter/Yogurt/Greek Yogurt/Lassi/Marscarpone/Cheese/Cream Cheese) Other Desserts (Meringue/Bananas Foster/Fried Dough/Funnel Cakes/Fritters/Churro/Snack Cakes) Other Flavour (Spicy/Ice/Lemongrass/Chicken/Cannabis/Malt/Molasses/Butternut/Wafer/Pepper/Pumpkin /Raisin/Rhubarb/Savory/Worcestershire/Taro/Tomato/Truffle/Cucumber/Yam/Popcorn/Pop pyseed/Currant/Passionflower) Pastry (Danish/Donut/Cinnabun/Muffin/Sticky Bun/Biscuit/Cannoli/Cream Puff) Peach/Nectarine (Georgia/White) Peanut (Peanut Butter) Pear Pie/Tart/Cobbler (Apple/Blueberry/Lemon Meringue/Coconut Cream/Banana Cream/Key Lime/Cinnamon/Boston Cream/Pecan) Pineapple Fruit/Juice Plum Fruit/Juice Popsickle/Creamsickle Raspberry Fruit/Juice/Cooler/Syrup Rice (Grain/Milk/Sticky/Sweet) Slushie/Shaved Ice/Italian Ice/Blue Spice (Anise/Cardamom/Clove/Ginger/Holiday/Mulled/Nutmeg/Pumpkin/Salt) Strawberry Fruit/Jam/Preserves/Syrup Sugar (White/Brown/Powdered/Glaze) Tea (Black/Green/Herbal/Iced/Thai Iced/Chai/Sweet/Earl Grey/Milk/Gyokuro) Tobacco (Cigar/Pipe/Turkish/American/RY4) Tropical or Exotic Fruit (Guava/Dragon Fruit/Fig/Guava/Kiwi/Mango/Papaya/Passion Fruit/Pitaya/Pomegranate) Unflavoured Vanilla (Bean/French) Woodsy/Smokey (Hickory/Mesquite/Oak/Sandalwood/Leather)