Pangaia is emblazoning textiles using a water-based dye derived from air pollution—a world’s first—but the London-based startup insists that it’s more than a click-baiting gimmick. Its latest capsule collection, which comprises hoodies, T-shirts, dresses, shorts, track pants, bucket hats, bags and even jersey slippers featuring prints using Air-Ink, is only the beginning, said Amanda Parkes,…