Retention of Fall-Out Constituents in Upper Layers of the Pacific Ocean as Estimated From Studies of a Tuna Population.

Hodge, Vernon F.; Folsom, T.R.; Young, D. R.

doi:10.2172/4610482

Cited by 10 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This value is about one-half of physical half-life of 8°Co (5.263y). A similar trend is found for the S°Co levels in the livers of albacore (Hodge et al, 1973;Krygier and Pearcy, 1977) which also show an apparent half-life of about 2 y for the period 1963 to 1969. Table 2 shows 6°Co content in sperm whale viscera: liver, kidney, and heart.…”

Section: Resultssupporting

confidence: 73%

Transfer of60Co from midwater squid to sperm whales

Umezu¹,

Ebihara

Minamisako³

et al. 1984

Journal of the Oceanographical Society of Japan

View full text Add to dashboard Cite

Sperm whales are notable squid-eaters. They feed mainly on medium to largesized cephalopods at midwater levels and defecate near the surface. This suggests the existence of an upward transport of 8°Co by sperm whales from the mesopelagic zone (150-1,200 m). To elucidate this squid-whale route for this artificial radionuclide, 6°Co content was determined in squid and in predator whales captured by commercial whaling. In the Cephalopoda livers 8°Co levels of 30-500 mBq kg -~ wet were found and in the viscera of Odontoceti (toothed whales)15-40 mBqkg -~ wet. About 0.3 % of 8°Co ingested was estimated to be retained in a 23-year-old male sperm whale. In the livers of Bryde's whales, ~°Co levels of 40-80 mBqkg -~ wet were detected, but not in euphausiids and sardines, their possible prey. The level of Co in sperm whales was nearly the same as in Bryde's whales. Specific radioactivity 6°Co/SgCo in mBq pg-i was several times higher in sperm whale (1.1-1.6) than in cephalopods (0.19-0.77). Eating prey with a high content of 6°Co in the 1960's may have contributed to the present body burden in sperm whales with a long-life span. However, the origin of 8°Co in Bryde's whales is unknown.

show abstract

Section: Resultssupporting

confidence: 73%

Transfer of60Co from midwater squid to sperm whales

Umezu¹,

Ebihara

Minamisako³

et al. 1984

Journal of the Oceanographical Society of Japan

View full text Add to dashboard Cite

show abstract

“…Previous studies that measured radionuclides from the Bikini atoll weapons tests in the 1940s–1960s attempted to infer migration patterns of pelagic animals, including yellowfin tuna T. albacares and albacore tuna Thunnus alalunga . − However, nuclear detonations led to extensive, widespread fallout from the atmosphere, and results of those pioneering studies could only provide general, highly inferential results. In contrast, the Fukushima plant failure represents a more discrete point source of radionuclides.…”

Section: Discussionmentioning

confidence: 99%

Radiocesium in Pacific Bluefin Tuna Thunnus orientalis in 2012 Validates New Tracer Technique

Madigan

Baumann

Snodgrass

et al. 2013

Environ. Sci. Technol.

View full text Add to dashboard Cite

The detection of Fukushima-derived radionuclides in Pacific bluefin tuna (PBFT) that crossed the Pacific Ocean to the California Current Large Marine Ecosystem (CCLME) in 2011 presented the potential to use radiocesium as a tracer in highly migratory species. This tracer requires that all western Pacific Ocean emigrants acquire the (134)Cs signal, a radioisotope undetectable in Pacific biota prior to the Fukushima accident in 2011. We tested the efficacy of the radiocesium tracer by measuring (134)Cs and (137)Cs in PBFT (n = 50) caught in the CCLME in 2012, more than a year after the Fukushima accident. All small PBFT (n = 28; recent migrants from Japan) had (134)Cs (0.7 ± 0.2 Bq kg(-1)) and elevated (137)Cs (2.0 ± 0.5 Bq kg(-1)) in their white muscle tissue. Most larger, older fish (n = 22) had no (134)Cs and only background levels of (137)Cs, showing that one year in the CCLME is sufficient for (134)Cs and (137)Cs values in PBFT to reach pre-Fukushima levels. Radiocesium concentrations in 2012 PBFT were less than half those from 2011 and well below safety guidelines for public health. Detection of (134)Cs in all recent migrant PBFT supports the use of radiocesium as a tracer in migratory animals in 2012.

show abstract

“…Hodge et al (1973) The low 6zZn specific activities in abyssobenthic fishes could be explained by the long time f;or passage through the food web to these carnivores. However, the low G"Zn activity in deep sea detrital-deposit feeders ( Osterberg et al 1963;Carey 1972) argues that little 65Zn reaches the deep sea floor.…”

Section: Discussionmentioning

confidence: 99%

“…The ,transit times for zinc-%, and perhaps other biologically utilizable materials, appear to be relatively long. Hodge et al (1973) also concluded from the long term decline of radionuclides in albacore that trace elements may be retained for decades in the upper layers of the ocean. The low 6zZn specific activities in abyssobenthic fishes could be explained by the long time f;or passage through the food web to these carnivores.…”

Section: Discussionmentioning

confidence: 99%

Biological transport of zinc‐65 into the deep sea1

Pearcy

Krygier

Cutshall

1977

Limnology & Oceanography

View full text Add to dashboard Cite

The specific activities of zinc-65 ('"Zn : Zn) in pelagic and benthic animals collected off Oregon were correlated with depth of capture to estimate vertical biological transport rates. Results suggest that about 2 yr are required for transport of aZn from near-surface to abyssobenthic animals. Vertical transport appears to be slower in upper waters, suggesting recycling of zinc within biological communities, and more rapid below 500 m. The long vertical transport time for zinc contrasts with the shorter times estimated for transport of zinc and other elements by fecal pellets. This raises questions about the importance of fecal pellets as a rapid transport mechanism for biologically required materials into the deep sea.

show abstract

Retention of Fall-Out Constituents in Upper Layers of the Pacific Ocean as Estimated From Studies of a Tuna Population.

Cited by 10 publications

References 5 publications

Transfer of60Co from midwater squid to sperm whales

Transfer of60Co from midwater squid to sperm whales

Radiocesium in Pacific Bluefin Tuna Thunnus orientalis in 2012 Validates New Tracer Technique

Biological transport of zinc‐65 into the deep sea1

Contact Info

Product

Resources

About