SAN DIEGO (AP) — The smell of rotten eggs permeates Steve Egger’s Southern California home, especially at night as the nearby Tijuana River foams up with sewage from Mexico before emptying into the Pacific Ocean. Egger, 72, says he and his wife have frequent headaches and wake up congested and coughing up phlegm. Their home is outfitted with a hospital-grade filtration system that cycles the air every 15 minutes. Despite those measures, “most nights we breathe in a horrible stench,” he said. “