Oil producer Shell and German chemical company BASF agreed on Monday to pay compensation that could reach 620 million reais ($316 million) to workers exposed over three decades to toxic chemicals at a Brazil plant, prosecutors said…The companies have agreed to pay individual compensation to 1,068 former workers at the plant and provide them with lifetime medical care, which prosecutors estimated could total up to 420 million reais. Shell and BASF would also make a separate 200 million reais payment for collective moral damages which would be used to build a maternity clinic in Paulinia and for donations to special health centers. Shell has maintained throughout the case, brought in 2007, that it believed there was no link between the operations at the plant and injury to workers' health, but it said it regretted the environmental contamination that occurred. Seventy-six workers pursuing individual court action must also decide within 30 days whether to take the compensation offer which would require them to drop their own cases…