By Belinda Goldsmith, July 21 (Thomson Reuters Foundation)

As British retailer Lush expands globally, the head of ethical buying at the handmade cosmetics company says he is facing an almost impossible challenge - ensuring all products are free of slave labour and other human rights abuses.

Simon Constantine, the son of two of Lush's founders, said sales doubling and an almost 50 percent jump in profits to 31 million pounds ($40 million) since 2013 created the potential for wider social impact by sourcing from more local communities.

But he said this growth had also opened a labyrinth of new problems for privately-owned Lush - which prides itself on products ethically sourced, environmentally friendly and not tested on animals - particularly as it expands in Asia....