Gulf of Maine Council on the Marine Environment

ironment The Gulf of'meCouncil on the Marine Environment Marine Environmental QualiCvI/ in the Gulf of Maine The Gulf of Maine is among the world's mosl pro- ton Harbour that have been heavily polluted in the ductive water bodies. It has enjoyed a reputation for past. pristine waters, unspoiled beaches, and high quality All densely populated and industrialized R- seafood. It also has been considered the standard by gions of the Gulf have been affected, to greater and which other coastal environments should be lesser degrees, by local sources of pollution. Per- judged. Recent studies, however, have shown that haps the best example of the widespread nature of certain nearshore regions of the Gulf, thought to be Althalrglr the GraH the problem is the closure of shei1fish harvesting relatively clean, are as polluted as other heavily of Maine as a areas all along the Gulf coast, largely due to patho- populated and industrialized East Coast sites wRlale remains gens from human waste. The economic loss of tbis (Gottholm and Turgeon 1992; Larsen 1991). For- clasn, some fishery and accompanying threat to human health tunately, widespread degradation of the rich Gulf nearshare areas are unequivocal signs of degradation of marine en- ecosystem has not yet occurred. At the same time, are as polfutcd as vironmental quality. On rare occassions, health of- contaminants are declining in some areas like Bos- most other east ficials also have issued advisories due to unaccept- Fact Sheet No. 94 - 1 in fish, sheIlfish, mnment and overfishing bas bad long term effects on offshore fishing stocks, such as herring on Georges Bank. This State of the Environment (SOE)Fact Sheet focuses on the threat to the marine environment from pollution. It examines the con- A#ar.ine prsii~rionIs such as tidal power in the the Introdrrclian by taminants in water, sediments, and tissues of the humans, directly ar region's marine organisms, especially in the indlrsrtly, of substances or energy Flgure 1 to the rnirrins . Indlcatlng niajor drelnage basins and underwater banks. environment result- ing 111 such rldalerl- orrs effects as harm to living resources; hazards to human tleaith; hlndrclrlee of marine activitjes; lmpslirrnaaf of f he quality far use of seawnter; and redudion of ameni- ties, including aesthetic waiua {Clark 1986). Gulf of kin- on the Marine Environment, 1991 nearshore environment, within 10 km uZ the coast. coal-fired generating plants (Gottholm and Possible biological effects and implications for hu- Turgeon 1992). These so-called point suurces dis- man health are discussed, as well as remedial action charge contaminants directly to the environment now being undertaken. through an effluent pipe or smoke stack. ~owever, indirect, nun-point sources in the Gulf of Maine Vie rzetwark of f he watershed are large and ubiquitous (Figure 21, region's rivers from urban and agricultural run-off to septic sys- carries a steady tems (Van Dusen and Hayden 1989). The Gulf of Maine is a "sea within a sea." The stream af corrhrni- coastlines of three New England States-Massa- Tbree-quarters of marine pollution comes nunls-pathogens, chusetts, New Hampshire, and Maine--and two from human activities on the land. The network of heavy nle2al%, Canadian Provinces-New Brunswick and Nova the Gulf's rivels carry a steady stream of contami- sediments! rrutrl- Scotia+nclose it on three sides. On its seaward nants-pathogens, heavy metals, sediments, nutrients, and synthetic edge, underwater banks isolate the Gulf from the ents, and synthetic compounds-and deposits campounds+ind full influence of the open Atlantic Ocean (Figurel). them in the nearshore environment. Activities on deposits them In Tagether the Gulf of Maine and Bay of Fundy form the coast also contribute to this loading. As well, tila r=arshsn a single oceanoghpbic system that, twice daily, re- prevailing winds transport significant amounts of envimnrncnt. ceives an ebb and flow 2000 times the volume of the airborne contaminants from populated and indus- St. Lawrence River. The Gulf also includes offshore trialized regions to the west, and dump them into areas such as Georges Bank which has been called the Gulf. Due to their low flushing capacity, New "an oceanic miracle," for its fish-producing capac- England estuaries tend to retain contaminants. ity. However, tides, currents, wind action, and storm The geography and oceanography of the Gulf surges eventually distribute them along the coast of Maine make it particularly vulnerable to human and out to sea. activities on its shores (Cdgan 1989). The total drainage area of the Gulf of Maine, 179 000 km2,is vast and, within the US.,the Gulf is the third most densely populated coastal region (pop 4 593 000). Contaminants that cause harm to organisms or bio- Compared to other U.S. coastal regions, there are logical comlnunities are called pollutants. Glo- relatively few large industrial sources of pollution, bally, the contaminants that pose the greatest such as wastewater treatment, pulp and paper, and threat to the marine environment are: sewage (bac- teria and viruses), excessive nutrients (e.g., phos- .- .- and nitrogen), synthetic organic corn- tion is as valid now as it was then. litter and plastics, metals, The presence of contaminants in the envimn- including oil and ment, for example, in wakr and sediments, does not necessarily imply any hadleffects. Their presence in living tissues, however, indicates potential not easily broken down and for ham. It confirms that the contaminants are the environment. These sub- biologically available and may spread throughout the food web. Health Canada and the U.S. Food and Unnatural levels of Drug Administration have set standards for fish contaminants In consumption for a limited number of potentially water, redlmerrts, toxic substances. In rare instances when these lev- or llvlng tlssuss els have been exceeded, authorities have issued should act as a'n health advisories. early warning that Some su bsrances can cause harm at extremely an ecosystem or nsidous process is known as low dosages. For example, dioxin is toxic in parts organism is under Concentrations of contaminan& per trillion. At the very least, unnatural levels of stress. progressively through the food web in contaminants-whether in water, sediments, or living tissues-should act as an early warning that an ecosystem or organism is under stress. Ultimately, ecosystem health and human welfare may be affected. f the food web. Heavy metals Heavy metals have been with us as major contami- I.. I.. as nants since tbe beginning of the Industrial Revolu- -'act. an early warning tion. Many New England rivers were contaminated :are poisons, for there is nothing without heavily with metals during the 19th century from aqualities. It is only the dose which makes industries which exploited local sources of ore and a thing a1 poison," wrote Paracelsus, the 16th-cen- tbe abundant hydropower of the region. High levels tury Swi s physician and philosoplier. His observa- i of chromium are still found in estuaries, such as the 3 Figure.. ,...-.. .. ... Saco River, Maine, and Great Bay, New Hampshire, --'end blomagnlflcatlon In due to the past activities of tanneries (Armstrong et marlnel- nl. 1976; Mayer and Fink 1980). Surveys of Casco and Penobscot Bays in Maine revealed that chromium, capper, and lead concentrations were comparable to levels from sediments at New England sites which are currently far more industrialized (Larsen et al. 1983a,1984a) Highest concentrations of most metals were found at the head of bays, suggesting that river flow is a major pathway for contaminants into the marine environment. Heavy metals in marine organisms A survey revealed high concentrations of metals in fish from the area of the Kennebec River plume- the wedge-like area at the mouth of the estuary, directly influenced by the warmer, fresher river flow The state f-, daneda's Environment, 1991 (NOAA 1987b). Surprisingly,livers of fish from tbe :t Ill Kennebec plunie were more contaminated than birds (Carson 1962) and killed fish as it made its those from beavily industrialized Boston and Salem way into rivers--and ultimately to the sea. It en- Harbors for every metal except chromium. The tered the inarinc food web where it was shown to drainage of a very large, industrial watershed could cause eggshell thinning, leading to reproductive Livers of fish frrrrn account for the high degree of contamination. Con- failure and population declines in Northern Gan- taminants have been linked to pulp and paper, tan- nets and other seabirds. Though it has been re- the Kennebsc River ning, and textile industries in the 'Kenncbec River placed by other pesticides, twenly years later, DDT plume were Inore basin, as well as non-point sources such as fanns, and its highly toxic breakdown product, DDE, per- carztaminated than tiacsa from treauiiy forestry, and urban developn~ent(Maine State Plan- sist in the environment. fndustrlaIlzed ning Office 1993). During the 1950s and 1960s large tracts of Boston and Salem More difficult to explainare the high levels of forest in New Brunswick were sprayed with DDT to harbours for every lead in rock crabs from West Boothbay Harbour, combat sprucc budworm infeslalions. An estimated metal except cchra- Maine. Lead levels in their gills were equal to or 5.7 million kilogralns were used annually (Mjniswr miurn. higher than background levels from New York and of Supply and Services 1991a). DDT entered the Philadelphia ofkbore solid waste dumpsites. Bay of Fundy as run-off from Ibe Sainl John River area. This large watershed drains not only forest Contamination with heavy metals is not lim- land but also agricultural areas where thc use of ited to coastal Maine. In the Bay of Fundy, striped pesticides conlinues to be relatively high.

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