- Impact of PCB and p,p -DDE Contaminants on Human Sperm Y:X Chromosome Ratio: Studies in Three European Populations and the Inuit Population in Greenland. Tiido, T., Rignell-Hydbom, A., Jönsson, B.A., Giwercman, Y.L., Pedersen, H.S., Wojtyniak, B., Ludwicki, J.K., Lesovoy, V., Zvyezday, V., Spano, M., Manicardi, G.C., Bizzaro, D., Bonefeld-Jørgensen, E.C., Toft, G., Bonde, J.P., Rylander, L., Hagmar, L., Giwercman, A., Inuendo, I. Environ. Health Perspect. (2006)