I agree with Buck and Michael
Just like Buck, I have driven its entire length from Cali to Florida and I can assure you that I-10 is a very safe interstate. I have also traveled by myself on most secondary roads that run along the border from California to Texas and I even driven on a few stretches of Mexican highways with a friend of mine and nothing bad happened. Anyway, I seriously doubt any drug smuggler would want to hang out anywhere near I-10 since it's a crowded area and the border patrolers are overly present. And even if they did, they won't want to get noticed just like any illegal immigrant. Plus, except for the El Paso area, I-10 doesn't run that close to the border.