TIME: “Colin Goddard lay in a pool of his own blood, hoping his racing heart would not tip off the approaching gunman that he was still alive. The shooter hovered over Goddard, paused and fired two more bullets into him anyway. Goddard survived the April 16, 2007 massacre at Virginia Tech, which killed 32 people and was the worst school shooting in U.S. history. Twelve years later, he tries not to dwell on the day, but he has dozens of constant reminders: bullet fragments lodged in his body, leaching toxins into his blood.

Like hundreds and possibly thousands of shooting survivors across the country, Goddard, a 33-year-old father of two, is suffering a lesser-known and often unrecognized side effect of gun violence: lead poisoning. When he was shot in his French class that spring day, one bullet pierced his right shoulder cleanly, but three others shattered when they hit his hips and left knee. Because the fragments did not pose life-threatening risks, trauma surgeons left them in his body—a common and widely accepted practice in emergency rooms throughout the United States. Now, with his blood lead levels seven times higher than what is considered safe, Goddard faces long-term health risks, including neurological problems, kidney dysfunction and reproductive issues.

The metal’s toxicity is well-documented, but only wildlife have so far benefitted from efforts to outlaw its use in bullets, and even those results have been limited. California on July 1 will become the first state to ban lead hunting bullets, the culmination of a yearslong battle that pitted environmentalists against the National Rifle Association and other gun-rights groups. “I was told, ‘You’re going to be fine in the long-term,’ and that’s not right,” Goddard says. “It throws you back when you realize you’re not out of the woods yet, and this terrible day is not entirely behind you.”