Defoliants and Herbicides

• A Study Is Retracted, Renewing Concerns About the Weedkiller Roundup - Problems with a 25-year-old landmark paper on the safety of Roundup’s active ingredient, glyphosate, have led to calls for the E.P.A. to reassess the widely used chemical.
• What to Know About Colombia’s Role in the Global Drug Trade Amid Trump’s Feud With Petro - President Gustavo Petro is locked in a war of words with President Trump over Colombia’s major role in the global drug trade. The issue is complicated.