It is important to stop incinerating our wastes not only because
incinerators contaminate local air, but also because they are
destroying the productivity of the oceans and other large water-bodies
such as Chesapeake Bay, Puget Sound, and the Great Lakes.
You might think the oceans are so large that puny humans could not
contaminate them to any significant extent. But you would be wrong.
The uppermost surface of the ocean forms a peculiarly important and,
until recently, poorly understood, ecosystem. Scientists refer to it as
the "sea-surface microlayer." The sea-surface microlayer is the top 50
micrometers of the ocean--a layer half the thickness of the period at
the end of this sentence, yet critically important to life in the
oceans or, for that matter, in any large body of water such as the
Great Lakes, the Gulf of Mexico, Puget Sound, or Chesapeake Bay. The
microlayer is composed of bacteria, yeasts, and molds in concentrations
as much as 10,000 times greater than in the water below. Microscopic
plants and animals also concentrate in the microlayer, creating an
invisible organic film on the surface of the water, rich in lipids
(fats and oils) and fatty acids.
The sea-surface microlayer is a highly productive habitat for a broad
array of living things. Numerous species of fish, including cod,
sole, menhaden, hake, anchovy, mullet, flying fish, greeling, saury,
rockfish, bluefish, mackerel, halibut and many others have surface-
dwelling egg or larval stages. In estuarine, coastal, and shelf areas,
blue crab, Dungeness crab, and lobster larvae also concentrate in the
surface film during mid-day, drawn there by the abundance of sunlight.
Because of its importance as a nursery for fish eggs and larvae, the
microlayer has great economic value.
In a Georgia salt marsh, 21-43% of the total productivity is
concentrated in the upper 0.55 mm. Average productivity (measured by
oxygen consumption) was 3000 times greater in the microlayer than in
the water below.
Unfortunately, the sea-surface microlayer is specially vulnerable to
pollution. Contaminants that settle out from the air (such as emissions
from incinerators, or from combustion of gasoline or coal) tend to
accumulate in the microlayer. So do contaminants deposited on the land,
many of which eventually wash into rivers and then the oceans.
Toxins in the microlayer typically occur at concentrations 100 to
10,000 times higher than in the water below.
Contaminants that have low solubility in water or that attach to
floatable particles (chlorinated hydrocarbons, pesticides and metals)
concentrate in the microlayer. Concentrations of these contaminants
hundreds or even thousands of times greater than EPA water quality
standards have been measured in the sea-surface microlayer of Puget
Sound, Chesapeake Bay and elsewhere.
Contaminants build up in the microlayer. Combustion byproducts called
polycyclic aromatic hydrocarbons (PAHs) in the Lake Michigan microlayer
range from 0.15 to 0.45 ppb [parts per billion], a million-fold
enrichment compared to the air above. The surface film of Biscayne
Bay, Florida, contained 2670 times higher concentration of DDT compared
to the water below. In a San Francisco salt march, lead was measured
at a concentration 6 to 14 times higher than in the water below and
in Narragansett Bay lead was 5 times more concentrated in the surface
microlayer than in the water below.
Atmospheric deposition (fallout) accounts for around 50% of the PAHs
and metals entering some coastal waters. As airborne particles
settle onto the surface of a water body, they become solubilized and
are rapidly introduced into the food chain via the high concentration
of microorganisms found in the microlayer.
Fish eggs are sensitive to environmental toxicants. So are embryos and
larvae, which are deformed or killed by hydrocarbons, metals, and
pesticides. In the ocean, most fish eggs, because of their high
content of lipids (fat or oil), float on the surface in direct contact
with the microlayer. Careful measurements in Puget Sound have shown
that the hatching success of larvae decreases with increasing
concentration of PAHs and heavy metals in the microlayer. Significant
contamination of the microlayer is considered to be any concentration
greater than 1 ppb PAHs and greater than 50 ppb metals. By this
criterion, in Chesapeake Bay, 30% of samples of the microlayer were
The killing power of contaminants in the microlayer is exemplified by
benzo(a)pyrene, or BaP, one of the PAHs. BaP is a strong carcinogen
created by the combustion of coal, gasoline, and many wastes, including
municipal trash. Experiments have shown that 0.3 ppb of benzo(a)pyrene
causes 2 to 5 times more misshapen trout larvae than normal. There was
a 30% death rate among sole embryos exposed to 0.1 ppb benzo(a)pyrene.
Yet in Puget Sound many samples from the sea-surface microlayer
measured 3 to 123 ppb benzo(a)pyrene.
Samples of the sea-surface microlayer from Los Angeles harbor induced
severe malformations in 100% of surviving larvae of kelp bass.
A contaminated microlayer can be carried by wind and surface currents
and deposit on beaches and along shallow coastlines where it can
contaminate shellfish and other species, such as herring, that lay
their eggs in such areas.
U.S. Environmental Protection Agency water quality criteria for PCBs is
30 parts per trillion (ppt). But sea-surface microlayer concentrations
of PCB in Puget Sound are up to 130 times higher than EPA's water
In Puget Sound in 1985 PAHs, which are carcinogenic, mutagenic and
teratogenic occurred in the majority (57%) of sea-surface microlayer
samples. Pesticides were detected in 28% of the sea-surface microlayer
In controlled tests, more than half the samples from the Puget Sound
microlayer caused a significant reduction in the normal hatching
success of fertilized sole eggs.
There seems to be little doubt that incineration, the combustion of
petroleum products, and of coal, is greatly reducing the productivity
of near-shore regions of the world's oceans. Unfortunately, these near-
shore regions are the most important from the viewpoint of
The consequences of this contamination are real. At a fish store in
Washington, DC, flounder now sells for $10 per pound, red snapper for
$12 per pound. At these prices, only the wealthiest among us can afford
to eat fish regularly. Until recently, fish was a free or low-cost
source of protein.
Fortunately, a possible legal mechanism already exists to protect the
oceans from land-based incineration.
In the FEDERAL REGISTER Vol. 39 (October 17, 1974), pg. 37058, EPA
(U.S. Environmental Protection Agency) stated that "in any case where
it can reasonably be anticipated that incineration of wastes at sea
will result in any such material, or emissions from the incineration of
such material, entering ocean waters, such incineration will require a
permit under the Ocean Dumping Act [the Marine Protection, Research and
Sanctuaries Act, 33 U.S.C. 1401-1444].
In a court case, EPA argued that incineration on ocean-going ships
constituted ocean dumping because incinerator emissions would enter the
oceans. The case was Seaburn, Inc. vs. United States Environmental
Protection Agency, Civ. A. No. 88-637, United States District Court,
District of Columbia, April 20, 1989. Seaburn, a waste disposal
company, had challenged EPA's decision to suspend its evaluation of the
company's application for an ocean-incineration permit. The District
Court held that the Agency's interpretation of the Ocean Dumping Ban
Act, to equate ocean incineration dumping with ocean dumping, was
reasonable. On pg. 7 of its motion for summary judgement the EPA argued
that "Ocean incineration is a process that converts some of the liquid
wastes into "residues" or emissions which are then "dispersed into the
atmosphere and generally deposited into the ocean." Thus, the EPA
argued, ocean incineration is really a form of ocean dumping.
The same logic leads to the conclusion that land-based incineration
anywhere within several hundred miles of an ocean constitutes ocean
dumping. U.S. policy on ocean dumping is firmly established: it is
banned. It is time to ban incineration too.
 J.T. Hardy, "The Sea Surface Microlayer: Biology, Chemistry, and
Anthropogenic Enrichment," PROGRESS IN OCEANOGRAPHY Vol. 11 (1982),
 John Hardy and others, "The Sea-surface Microlayer of Puget Sound:
Part I. Toxic Effects on Fish Eggs and Larvae." MARINE ENVIRONMENTAL
RESEARCH Vol. 23 (1987), pgs. [227-249.]227-249.
 J.T. Hardy and others, "The Sea-surface Microlayer of Puget Sound:
Part II. Concentrations of Contaminants and Relation to Toxicity."
MARINE ENVIRONMENTAL RESEARCH Vol. 23 (1987), pgs. 251-271.
 Jeffrey N. Cross and others, "Contaminant Concentrations and
Toxicity of Sea-surface Microlayer Near Los Angeles, California,"
MARINE ENVIRONMENTAL RESEARCH Vol. 23 (1987), pgs. 307-323.
 712 F. Supp. 218 (D.C.C. 1989). Thanks to Rick Parrish of
Charlottesville, VA, for alerting us to this important court case and
Descriptor terms: water pollution; incineration; waste disposal
technologies; puget sound; chesapeake bay; los angeles harbor;
wildlife; ga; fish; pahs; heavy metals; water quality;