Yes. There are urban planter box options that are safe for growing vegetables, but “safe” depends on the material, the liner, the soil mix, and where the planter sits. For edible gardening, choose materials that are food-contact-safe or inert, and avoid materials that can leach harmful chemicals into the root zone.
Good options include food-grade HDPE or polypropylene plastic planters, untreated rot-resistant wood such as cedar or cypress, stainless steel, and galvanized steel lined with a food-safe HDPE liner. Concrete and stone can also work if they are fully cured and, if needed, lined; unsealed concrete may raise soil pH over time. Food-grade fabric grow bags are another practical urban choice because they drain well and are usually made from woven polypropylene. Terracotta is safe when unglazed and naturally fired, but avoid unknown glazes that may contain lead.
Be cautious with pressure-treated wood. Older CCA-treated lumber contains arsenic and should not be used for vegetables. Newer copper-based treated wood is less concerning but still not ideal for edible roots, especially in acidic soil; if you use it, line the inside with food-grade HDPE and ensure drainage. Avoid recycled tires, railroad ties, unknown pallets, PVC, unidentified recycled plastics, and painted containers with chipping or lead-based paint. Galvanized steel is generally acceptable, but zinc can leach in acidic, fertilizer-heavy soil, so a food-safe liner is a smart precaution. Stainless steel is a low-risk metal choice.
For urban gardens, the bigger risk is often contaminated soil or air pollution rather than the box itself. Use a clean potting mix or tested compost instead of digging up unknown urban soil. If you must use site soil, test it for lead, arsenic, cadmium, and pH first. Place planters away from busy road dust, old painted buildings, and industrial drip zones. Add mulch to reduce dust and splash, grow leafy crops and herbs in clean media, and wash produce before eating.
Also check drainage, container depth, and irrigation. Most herbs and lettuce need about 20–30 cm of soil depth; tomatoes, peppers, and root crops need 30–45 cm. Use potable water, avoid roof runoff unless tested, and keep coatings and liners intact. With food-grade materials, clean soil, and sensible placement, urban planter boxes can be a safe and productive way to grow vegetables.