Europe’s commodities traders are warning that new regulations set to be released within days could roil markets and push up costs for a range of essentials from crude oil to chocolate. A final draft of expanded rules governing the European Union’s oversight of financial markets is expected to extend its authority over firms that focus on trading in oil, farm products, industrial metals like copper and a host of other commodities. It would add a new layer of scrutiny for an industry that has historically operated with limited oversight . These companies—like BP BP 0.80 % PLC, Glencore GLNCY -7.01 % PLC and Vitol Group—buy and sell huge volumes of oil and industrial metals on a daily basis, hedging their stocks of raw materials with sizable positions in financial markets. Though it is difficult to quantify just how big they are, Vitol stunned market watchers in 2008 when regulators […]