NEW YORK — Remember when teenagers were grubby? Well, they’re scrubbed, powdered and perfumed now, thanks to the efforts of mass marketers. This year will see the introduction of no fewer than five bath lines, all aimed at the under-20s. Above, from left, items from Target’s Buttercup line, Caboodles, Delhar’s Body@Best, which helped launched the trend, and Burlington’s Cafe Society. For more on the trend, see page 10.