Rachel's Precaution Reporter #58, October 4, 2006


[Rachel's introduction: Despite international agreements to protect the Great Lakes from industrial contamination, most of the fish in the Great Lakes are unfit for human consumption: "If these [hormone- disrupting] health endpoints were included in the [risk assessment] calculations, most Great Lakes fisheries would likely have to be closed with devastating effects on fishing communities." Clearly, more precaution is needed.]

[Editors' introduction: The Great Lakes Water Quality Agreement between the U.S. and Canada is currently being re-examined through a public process of consultation. Here, a scientist knowledgable about Great Lakes water quality issues, who has asked to remain anonymous, writes about the precautionary principle as a way to preserve and restore the Great Lakes ecosystem.]

Traditional use of Precaution: As a Response to Failed Regulations

Much of the focus of the precautionary principle has been on pre- market testing of chemicals to ensure that they will not cause harm to humans or the environment when they are introduced into commerce in the future.

Over the past forty years, governments tend to have progressively abrogated their responsibilities for protecting the public from harms caused by particular chemicals.

Even when information was available about the harm that was being done to fish, wildlife and humans populations, those in authority were reluctant to prohibit activities involving the injurious chemicals.

With the breakdown of the system for effective regulation of chemicals already in commerce, the response within civil society was to demand a precautionary approach so that the 'safety' of chemicals would be documented before entry into commerce.

Another Use for Precaution: Dealing with Past Contamination

Releases of persistent toxic substances have caused extensive damage within the Great Lakes basin over the past century. In the 1960s, when civil society was expressing its outrage over many injustices including environmental health (Habermas, 1970; Adkin, 1998), the United States and Canadian governments responded with legislation and programs that included negotiation and signing of the Great Lakes Water Quality Agreement.

The International Joint Commission (created by a U.S.-Canada treaty in 1909 to regulate activity in the shared waters of the Great Lakes) was given special responsibilities including providing advice to the two governments on the injury to health and property from trans- boundary pollution.

There were many uncertainties in linking the releases of persistent toxic substances to the damage to human health and to fish and wildlife populations and the tendency was to postpone decision making to prohibit activities involving the substances while the uncertainties were reduced through scientific research. Meanwhile the damage continued.

The public response has been that, in the absence of timely and effective decision making, a precautionary approach was needed not only for chemicals likely to be manufactured or introduced into Great Lakes commerce in the future, but also to the exposures that occur today as a result of historic activities involving chemicals released in the past. Recently, the Great Lakes Science Advisory Board of the International Joint Commission (2006) reviewed the recent literature on the effects of exposures to persistent toxic substances.

About 4.7 million Americans eat Great Lakes fish and many are women of childbearing age (Tilden and others, 1997). Epidemiological research over the past twenty-five years has shown not only the effects on reproduction but also the particular susceptibility of the developing fetus to exposures to persistent toxic substances. The effects include changes in cognitive and behavioural development and in immune function mainly attributable to PCBs. Because these effects are mostly imperceptible in the individual (Beck, 1992) but devastating for the exposed population, it is essential to take a precautionary approach to the consumption of Great Lakes fish. Fish are resources and an important source of nutrition. The dilemma posed by the presence of these compounds in Great Lakes fish relates to both the economic damage to the valuable fisheries as well as the toxicological hazards they pose to humans while being nutritious food.

While the precautionary principle has not been incorporated into the current Great Lakes Water Quality Agreement, the Science Advisory Board (International Joint Commission, 2006) noted the relevance of the precautionary principle for protecting human health from exposures to persistent toxic substances and recommended a binational approach to the use of the precautionary principle in the management of chemicals in the Great Lakes basin.

Two Precautionary Strategies

There are two precautionary strategies that have been employed for reducing exposures to these hazards in the Great Lakes. The immediate response has been for governments to issue advisories to the public on the risks posed by the consumption of Great Lakes fish taken from particular localities and to restrict commercial fishing for certain species in designated places. As an expedient response to the immediate hazards, this measure, based on traditional risk assessment, has been successful at reducing exposures. But in the calculations, it has tended to ignore the subtle developmental effects caused by endocrine disruptors operating at concentrations sometimes far below the "safe" levels. If these health endpoints were included in the calculations, most Great Lakes fisheries would likely have to be closed with devastating effects on fishing communities.

The second approach has been to undertake remedial actions to "virtually eliminate" the contaminants, not only from discharges, but also from sediments. While many might not consider this to be precautionary given the extensive knowledge now available on the hazards posed by these compounds and the injury already documented, it is with an eye on safeguarding future generations that the decisions are being made. The scale of these precautionary measures is immense. On the US side, there are about 75 million cubic yards of contaminated sediment that need to be addressed of which 3.7 million cubic yards have so far been removed. Canada has not yet established a credible program for addressing the 44.7 million cubic yards of contaminated sediments and so far has only removed 0.045 million cubic yards.

The Great Lakes Water Quality Agreement is currently being reviewed through an extensive public consultative process with a possible view to amendment or renegotiation. During the operation of the Agreement over the past 35 years, concentrations of many persistent toxic substances have declined significantly and though many of the effects are still occurring, their incidence and severity have been reduced.

Increasing concentrations of brominated flame retardants and perfluoro octane sulphonates in fish and wildlife tissues during this period of time reveal the susceptibility of this immense ecosystem to the introduction of unregulated chemicals despite the agreement not to pollute the boundary waters to the injury of health or property.

Participants in the consultations have repeatedly expressed the need to incorporate the precautionary principle into the Great Lakes Water Quality Agreement to protect human, fish and wildlife health not only from new chemicals, but also from exposures to persistent toxic substances released from past human activities.


Habermas, J (1970) Toward a Rational Society: Student Protest, Science, and Politics (Beacon Press: Boston) 132 pp

Adkin, L (1998) Politics of Sustainable Development; Citizens, Unions and the Corporations (Black Rose Books: Montreal) 346 pp

International Joint Commission (2006) Priorities 2003 -- 2005: Priorities and Progress under the Great Lakes Water Quality Agreement. http://www.canamglass.org/glwqa/files/prioritiesfullreport.pdf

Tilden, J, Hanrahan, LP, Anderson, H, Palit, C, Olson, J, MacKenzie, W and the Great Lakes Sport Fish Consortium (1997) 'Health advisories for consumers of Great Lakes sport fish: Is the message being received?' Environmental Health Perspectives 105(12):1360-1365

Beck, U (1992) Risk Society: Towards a New Modernity (Sage: London) 260 pp