Poor recent economic data and an uncertain outlook on the global recovery sparked a broad sell-off in the industrial metals and mining sector on Thursday. Worries of a US downgrade, an escalating debt crisis in the Eurozone and slowing manufacturing growth in China have fuelled demand concerns for industrial metals as of late. As such, the price of copper tumbled close to a one-month low. Copper futures were 1.46% lower at $426.30 at 15.41pm in London.International Ferro Metals, Discovery Metals and Talvivaara Mining were all in the red, Talvivaara being the worst performer, losing over 10%.Meanwhile, strong gains for FTSE 100 giant Unilever boosted the food producing and processing sector, which was the best performing sector of the day. Strong growth in emerging markets helped Anglo-Dutch food and household goods giant Unilever post higher sales and profits in the first half. The maker of Dove soap, Magnum ice creams and a host of other brands, posted turnover of €22.79bn for the first half, up 4.1% from the same period a year ago, while net profit climbed by 9% to €2.4bn. BCTop performing sectors so far todayFood Producers & Processors 5,206.46 +3.03%Tobacco 31,934.80 +0.54%Mobile Telecommunications 3,880.51 +0.24%Bottom performing sectors so far todayIndustrial Metals & Mining 6,256.07 -5.75%Industrial Engineering 6,682.49 -5.68%Oil Equipment, Services & Distribution 21,780.77 -5.44%Chemicals 6,746.40 -4.86%Aerospace and Defence 2,989.01 -4.63%