The organochlorine pesticides pentachlorophenol and dichlorodiphenyltrichloroethane increase secretion and production of interleukin 6 by human immune cells.

The environmental contaminants pentachlorophenol (PCP) and 4, 4'-dichlorodiphenyltrichloroethane (DDT) are detected in some human blood samples at levels as high as 5 μM (PCP) and 260 nM (DDT). Several cancers are associated with exposures to these contaminants. IL-6 is a pro-inflammatory cytokine that when dysregulated stimulates inflammatory diseases and tumor progression.