with massive toxic contamination.
Though PCB levels have generally declined slightly in Puget Sound since they were banned in the 70's, they continue to accumulate in long-lived mammals such as orcas, and are passed on to their young through the placental wall and in mother's milk. Present orca generations carry loads that may have begun to accumulate in their mothers' bodies even before they were born. For example J18, or Everett, a young male who died early in his maturity in January 2000, lacked immunity to common diseases and his sperm count was zero. He carried a massive load of PCBs in his tissues.
www.epa.gov/superfund/sites/npl/wa.htm (October, 2001)
For more background on PCBs, see Ohio State University's PCB fact sheet.
Recently scientists have become aware of a new threat to both orcas and humans, in the form of fire-retardant chemicals called PBDEs, found in everyday household products.
For information on PBDEs, see:
Fireproof killer whales (Orcinus orca): flame-retardant chemicals and the conservation imperative in the charismatic icon of British Columbia, Canada by Peter S. Ross (270KB)