In collaboration with the Guandong Poison Control Center, NCI carried out a cross-sectional study of early biologic effect biomarkers of genotoxicity and immunotoxicity in workers exposed to trichloroethylene (TCE) and unexposed controls in the Guangdong Province, China in 2006. Investigators found that the total lymphocyte count and all major lymphocyte subsets were statistically significantly lower in workers exposed to TCE than in controls, and there was a significant dose–response relationship across the categories of controls and lower- and higher-exposed workers. Given that altered immunity, including immunosuppression, is a risk factor for non-Hodgkin lymphoma, these results add to the biologic plausibility that TCE is a lymphomagen. Urine samples are currently being analyzed for TCE and its key metabolites to provide insight into the human metabolism of TCE across a wide range of exposure levels. Investigators have reported for the first time that TCE exposure is associated with increased levels of the urinary kidney injury molecule‑1, a kidney-specific membrane protein that is strongly up-regulated in injured cells throughout the kidneys. This could help add to the biologic plausibility that TCE causes kidney cancer.