This study provides a global baseline for barium, gold, titanium and strontium as marine pollutants using the sperm whale (Physeter macrocephalus) as an indicator species. Barium, gold, titanium and strontium are metals that are little studied in marine environments. However, their recent emergence as nanomaterials will likely increase their presence in the marine environment. Moreover, nanosized particles are likely to exhibit toxic outcomes not seen in macrosized particles. Biopsies from free ranging sperm whales were collected from around the globe. Total barium levels were measured in 275 of 298 sperm whales tested for barium and collected from 16 regions around the globe. The global mean for barium was 0.93 +/- 0.2 ug/g with a detectable range from 0.1 to 27.9 ug. Total strontium levels were measurable in all 298 sperm whales producing a global mean level of 2.2 +/- 0.1 ug/g and a range from 0.2 to 11.5 ug/g. Total titanium levels were also measured in all 298 sperm whales producing a global mean level of 4.5 +/- 0.25 ug/g with a range from 0.1 to 29.8 ug/g. Total gold levels were detected in 50 of the 194 sperm whales collected from 16 regions around the globe. Detectable levels ranged from 0.1 to 2.3 ug/g tissue with a global mean level equal
to 0.2 +/- 0.02 ug/g. Previous reports of these metals were much lower than the mean levels reported here. The likely explanation is location differences and consistent with this explanation, we found statistically significant variation among regions. These data provide an important global baseline for barium, gold, titanium and strontium pollution and will allow for important comparisons to be made over time to assess the impact of nanomaterials on whales and the marine environment.
Last date updated on June, 2014