A hearing last month in federal court will set the stage for upcoming litigation against Syngenta, manufacturer of Paraquat. More than 600 lawsuits alleging the agrochemical giant knew its flagship weedkiller causes Parkinson’s were combined into what is known as multidistrict litigation. As Yogi Berra might say: It’s déjà vu all over again. Five years ago, the once seemingly invincible Monsanto Co. was dealt its first searing courtroom loss over allegations that its glyphosate weed killer causes cancer and Monsanto worked to hide the risks. That loss was followed by another, and another and the global recognition of damning internal Monsanto documents that ultimately led Monsanto owner Bayer AG to agree to pony up more than $11 billion to settle thousands of cancer claims. The litigation still lingers as Bayer wrestles with angry investors and plans to remove glyphosate-based products, such as the widely used Roundup herbicide, from the U.S. consumer market. Now it’s Syngenta’s turn. The mass tort …