The CDPH Environmental Health Laboratory Branch (EHLB) provides technical expertise and new measurement methods for air quality and biochemical speciation to identify emerging environmental pollutants and promote the health of all Californians. EHLB has a multidisciplinary staff of 30 experts in chemistry, toxicology, aerosol science, ventilation, engineering, and epidemiology. The EHLB Biochemistry Section conducts environmental testing for lead-poisoned children; biomonitoring of heavy metals, organic pollutants, and chemical metabolites; emerging contaminants identification; and intervention studies. The EHLB Air Quality Section provides measurements and technical guidance on indoor air pollutants, including control measures and infectious aerosols; emerging product emissions; commun