Concentrations of Mercury and Selenium in Alaskan Steller Sea Lion Populations

Abstract

Mercury (Hg) is a neurotoxin that can cause health issues or even death. In Alaskan Steller sea lion (SSL) populations, Hg concentrations were observed to vary by region and time. These observations are of interest because SSLs, particularly the western population segments, are classified as an endangered species. This study intends to investigate what may be causing regional Hg differences and if there are other elemental correlations. Blood and hair samples were obtained from SSL pups. The hair samples were formed while the pup was in utero, so concentrations are reflective of the mother’s diet. Hair samples were not received in time to be included for consideration in this document, but the blood samples were digested and then analyzed by inductively coupled plasma mass spectroscopy (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES), methods that are used to determine concentrations of elements in solution. These analytical methods were chosen because they may be used with different sample types, and they are capable of detecting a variety of elements. These techniques allow other elemental trends, in addition to the previously observed behavior of mercury and selenium, to be observed.