European markets started the session ahead boosted by positive economic data from China, but turned negative after new figures showed euro zone industrial output plunged again in April.The European Union’s statistics office said production fell by 21.6 percent, worse than March’s 19.3 percent, which was the previous record year-on-year decline. That pushed the euro down against the dollar. Mining and energy companies suffered as oil and metals prices slipped. Crude fell with investors concerned that the doubling of prices since February has been too much and is getting ahead of the recovery in the real economy. Pharmaceutical companies rose as the World Health Organisation declared a pandemic for the A (H1N1) flu strain.