Organic or conventional? It’s a choice many grocery shoppers are faced with, over and over. The price difference is easy to see; it’s right there on the product. The quality difference is much harder. Is the organic milk better for your kids? Is the conventional lettuce more likely to carry pathogens? Do organics do us more good (in the form of better nutrition), and do they do us less harm (in the form of fewer contaminants and pathogens)?