Particles in Mexico City Smog (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption Needle-like particles containing lead, zinc, and chlorine were among the several forms of metallic particles collected at the T0 site during the MILAGRO Campaign. Credit Brian Moffet, Lawrence Berkeley National Laboratory, MILAGRO Campaign Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.