Lanolin is a natural wax coating on sheep wool that is removed by boiling the wool and collecting the wax. The sheep are treated with a pesticide dip which contains chemicals such as DDT, lindane, and diazinon to control parasites.

The OP Insecticide Diazinon Alters the Wiring of the Developing Brain

Almost every issue of Environmental Health Perspectives contains a new study exploring the ways organophosphate (OP) insecticides disrupt the developing brain and nervous system. In the March 2008 issue the focus is on diazinon. The team of government-funded scientists found that very low levels of diazinon reduced the number of brain cells, altered the function of acetylcholine synapses, and disrupted the normal pattern of brain development, leading to "lasting deficits in cognitive performance and alterations in emotional responsiveness."
The Organic Center
Source: "T.A. Slotkin et al., "Neonatal Exposure to Low Doses of Diazinon: Long-Term Effects on Neural Cell Development and Acetylcholine Systems," Environmental Health Perspectives, Vol. 116, No. 3, March 2008