THE M/V SELENDANG AYUOIL SPILL SUBSISTENCE SEAFOOD SAMPLING PROGRAM AND PUBLIC HEALTH EVALUATION PROCESS

Abstract

ABSTRACT On December 8, 2004, the M/V Selendang AYU, a bulk freighter, ran aground on the western shoreline of Unalaska Island, Alaska, spilling an estimated 339,538 gallons of intermediate fuel oil and 14,680 gallons of marine diesel. A primary concern arising from this incident was the potential contamination of traditional subsistence seafood resources consumed by tribal members and others on Unalaska Island. The process of addressing this concern consisted of the following components: 1) formation of a subsistence seafood ‘core’ or management team that included representatives of the local tribe, native corporation, federal and state agencies, and the responsible party; 2) formation of an advisory team representing technical specialists from non-governmental organizations (NGOs), academia, and subsistence users; 3) identification of important subsistence seafood resources, including intertidal mussels, sea urchins, chitons, salmon, cod and sea lions; 4) a consumption survey of major subsistence seafood users from Unalaska Island; 5) the collection of 56 samples in 2005 and 9 in 2006 by teams that included representatives of the core and advisory teams; 6) polycyclic aromatic hydrocarbon (PAH) analysis and organoleptic and paralytic shellfish poison (PSP) testing of the collected samples; 7) a risk-based public health evaluation of the analytical results of collected samples by the State of Alaska Division of Public Health; and 8) communication of the results to the public. In the core spill area (Skan and Makushin Bays), only one subsistence sample contained PAHs exceeding risk-based screening criteria. This was a mussel sample collected in April 2005 prior to clean-up actions. No samples collected in 2006 exceeded public health screening criteria. In the main subsistence area (Unalaska Bay), only one chiton sample collected in June 2005 exceeded risk-based public health screening criteria. However, it was determined that the elevated PAH concentrations were not derived from the Selendang AYU. Subsequent samples collected from the same location could not confirm elevated PAHs. Overall, PAHs were not present at levels of health concern, but two samples contained PSP toxin above regulatory guidelines. Due to PSP concerns, the State of Alaska has an on-going advisory against the consumption of locally harvested shellfish that pre-dates the spill.