The southern Essonne department specialises in science and technology, and the south-eastern Val-de-Marne, with its wholesale Rungis food market, specialises in food processing and beverages. The Paris region's manufacturing decline is quickly being replaced by eco-industries: these employ about 100,000 workers. In 2011, while only 56,927 construction workers worked in Paris itself, its metropolitan area employed 246,639, in an activity centred largely around the Seine-Saint-Denis (41,378) and Hauts-de-Seine (37,303) departments and the new business-park centres appearing there.

What does the southern Essonne department specialize in?