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These known characteristics suggest there are at least three scientifically acknowledged modes of material transport from the deep ocean to

shallow

waters:

Upwelling;

and

Biographic

Transport;

Meridional

Circulation

Overturning. The EPA itself recognizes that persistent organic pollutants (POPs) such as PCBs, “circulate globally via the atmosphere, oceans, and other pathways, POPs released in one part of the world can travel to regions far from their source of origin. Therefore, they are chemicals of both local and global concern.”45

1.

Biographic Transport: Marine life

that has taken up PCBs in deep water at the disposal site can transport PCB material via migration and predatory consumption to the shallow marine ecosystem, which can continue up the food chain to humans. Sunken SINKEX vessels typically rest in the bathylpelagic zone (1,000-4,000 meters). Biographically speaking, organisms from each zone have contact with organisms from the zone above and below, allowing for food transfer and PCB uptake through the water column. “Undoubtedly, there is considerable trophic [feeding] interaction among these larger epipelagic fishes [albacore, blue shark, swordfish, etc.] and their meso- and bathypelagic counterparts during diel

[daily] vertical migration.” 46

Additionally, an assemblage

of

vertically

migrating marine organisms, called the Deep Scattering Layer (DSL), travel from the deep ocean to the shallows at night to feed where

trophic interaction occurs.47 recorded at all depths to 3,000

DSLs have meters.48

been

Chemosphere, Volume 40, Issue 6, March 2000, Pages 651- 660

http://www.epa.gov/oppt/tribal/pubs/TribalNewsletter1of2.pdf Monterey Bay National Marine Sanctuary Site Characterization – Biological Communities and Assemblages – Pelagic Zone. http://montereybay.noaa.gov/sitechar/pelagic5.html 45 46

IBID. Opdal, A.F., Godo, O.R., Bergstad, O.A., Fiksen, O, 2007. Distribution, identity, and possible processes sustaining meso- and 47 48

HUMAN HEALTH RISK

The ocean food web is interconnected, with humans acting as quaternary (fourth layer) consumers (consuming tertiary consumers). PCB’s ability to accumulate in the environment and in organisms means that organisms at higher trophic levels (higher in the food chain), such as humans, are at higher risk of toxic concentrations of PCBs than marine organisms themselves.49 Marine mammals such as whales and dolphins are also at higher risk.

The conceptual model used by the Navy and MARAD to evaluate the human health and ecological risks of sunken warships suggests the deep sea community does not interact with the shallow marine ecosystem, and as such, they failed to recognize the realities of the ocean food

web.

2.

Upwelling:

The

physical

marine

transport process called upwelling routinely moves materials from deep water to surface water.50 Upwelling can occur in coastal regions as well as the open ocean,51 and can be wind or tide-induced. Both types of upwelling do not typically occur in isolation, but rather coexist.52

Open ocean winds cause surface waters to diverge from a region (causing upwelling) or to

converge

toward

some

region

(causing

downwelling).53 These movements are essential to stirring the ocean, delivering oxygen to depth, distributing heat, and bringing nutrients to the surface.54

bathypelagic scattering layers on the northern Mid-Atlantic Ridge

Barnthouse, Glaser, Young, 2003 Tomczak, M.,1998. Shelf and Coastal Oceanography. http://www.es.flinders.edu.au/~mattom/ShelfCoast/notes/chapte r06.html 49 50

http://oceanmotion.org/html/background/upwelling-and- downwelling.htm 51

Tomczak, M.,1998. Shelf and Coastal Oceanography. http://www.es.flinders.edu.au/~mattom/ShelfCoast/notes/chapte r06.html 52

http://oceanmotion.org/html/background/upwelling-and- downwelling.htm 53

54

azmanian Aquaculture and Fisheries Institute http://www.redmap.org.au/resources/impact-of-climate-change-

BASEL ACTION NETWORK

23

2011

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