Model
Digital Document
Description
Odontocetes obtain nutrients including essential elements through their diet and are exposed to
heavy metal contaminants via ingestion of contaminated prey. We evaluated the prevalence,
concentration, and tissue distribution of essential and non-essential trace elements, including
heavy metal toxicants, in tissue (blubber, kidney, liver, skeletal muscle, skin) and fecal samples
collected from 90 odontocetes, representing nine species, that stranded in Georgia and Florida,
USA during 2007–2021. Samples were analyzed for concentrations of seven essential (cobalt,
copper, iron, manganese, molybdenum, selenium, zinc) and five non-essential (arsenic, cadmium,
lead, mercury, thallium) elemental analytes using inductively-coupled plasma mass spectrometry.
Risso’s dolphins (Grampus griseus) and short-finned pilot whales (Globicephala macrorhynchus) had
the highest median concentrations of mercury, cadmium, and lead, while dwarf sperm whales
(Kogia sima) had the lowest. Adult pygmy and dwarf sperm whales that stranded in 2019–2021
had higher concentrations of arsenic, copper, iron, lead, manganese, selenium, thallium, and zinc
compared to those that stranded in 2010–2018, suggesting an increasing risk of exposure over
time. The highest concentrations of many elements (e.g., cadmium, cobalt, copper, manganese,
molybdenum, thallium, zinc) were in fecal samples, illustrating the usefulness of this noninvasively
collected sample. Aside from fecal samples, hepatic tissues had the highest concentrations
of iron, manganese, mercury, molybdenum, and selenium in most species; renal tissues
had the highest concentrations of cadmium; skin had the highest concentrations of zinc; and
copper, arsenic, and lead concentrations were primarily distributed among the liver and kidneys.
Phylogenetic differences in patterns of trace element concentrations likely reflect species-specific
differences in diet, trophic level, and feeding strategies, while heterogeneous distributions of
elemental analytes among different organ types reflect differences in elemental biotransformation,
elimination, and storage. This study illustrates the importance of monitoring toxic contaminants in stranded odontocetes, which serve as important sentinels of environmental
contamination, and whose health may be linked to human health.
heavy metal contaminants via ingestion of contaminated prey. We evaluated the prevalence,
concentration, and tissue distribution of essential and non-essential trace elements, including
heavy metal toxicants, in tissue (blubber, kidney, liver, skeletal muscle, skin) and fecal samples
collected from 90 odontocetes, representing nine species, that stranded in Georgia and Florida,
USA during 2007–2021. Samples were analyzed for concentrations of seven essential (cobalt,
copper, iron, manganese, molybdenum, selenium, zinc) and five non-essential (arsenic, cadmium,
lead, mercury, thallium) elemental analytes using inductively-coupled plasma mass spectrometry.
Risso’s dolphins (Grampus griseus) and short-finned pilot whales (Globicephala macrorhynchus) had
the highest median concentrations of mercury, cadmium, and lead, while dwarf sperm whales
(Kogia sima) had the lowest. Adult pygmy and dwarf sperm whales that stranded in 2019–2021
had higher concentrations of arsenic, copper, iron, lead, manganese, selenium, thallium, and zinc
compared to those that stranded in 2010–2018, suggesting an increasing risk of exposure over
time. The highest concentrations of many elements (e.g., cadmium, cobalt, copper, manganese,
molybdenum, thallium, zinc) were in fecal samples, illustrating the usefulness of this noninvasively
collected sample. Aside from fecal samples, hepatic tissues had the highest concentrations
of iron, manganese, mercury, molybdenum, and selenium in most species; renal tissues
had the highest concentrations of cadmium; skin had the highest concentrations of zinc; and
copper, arsenic, and lead concentrations were primarily distributed among the liver and kidneys.
Phylogenetic differences in patterns of trace element concentrations likely reflect species-specific
differences in diet, trophic level, and feeding strategies, while heterogeneous distributions of
elemental analytes among different organ types reflect differences in elemental biotransformation,
elimination, and storage. This study illustrates the importance of monitoring toxic contaminants in stranded odontocetes, which serve as important sentinels of environmental
contamination, and whose health may be linked to human health.
Member of