Consumers turning to organic food in the wake of warnings about antifreeze-laden toothpaste, poisoned pet food, and antibiotic-laced fish may be in for a surprise. The same country blamed for those scares, China, is quietly muscling in on the organic market. Upscale grocery chains like Trader Joe's and Whole Foods now import popular organic snacks such as edamame and canned staples such as kidney beans from China. That has made some buyers looking for pristine, all-natural food a bit skittish. ......Organic produce imported from China carries the U.S. Department of Agriculture's organic logo and is certified by private firms authorized...