 The western Mediterranean Sea and the south-west Iberian Peninsula were identified as “hotspots”.Monsanto manufactured PCBs at its chemical plant in Newport, South Wales, until the mid- to late-1970s.During this period, waste matter, including PCBs, from the Newport site was dumped at a disused quarry near Groes-faen, west of Cardiff, and Penhros landfill site from where it continues to be released in waste water discharges.