I would monitor the oil level very carefully for now. Usually blue smokes means leaky piston rings or some how oil is getting into the cylinder area. If it is bad enough, you will foul your plugs and clog your cat. Has your car over heated recently and how is your coolant level? You could use a thicker oil such as a diesel oil, but if the leak is big enough you will need a compression test and likely an overhaul.
My neighbor's 2003 Camry (2.4L) had the same issue. The cause was 2-fold, first there was sludge built up under the valve cover and the 2nd needing a head gasket and engine block because the head bolt threads pulled out of the block. I would keep a close eye on your oil level, pull the valve cover and check for sludge, inspect for leaks around the head gasket area, and most definately check for loose head bolts as the threads may be stripped in the block.