(photo:NBEN-RENB)

Retour sur les rivières de la mort; Un hommage à Rachel Carson 

Dans son discours
du Jour de la Terre,
Inka Milewski, du
Conseil de
conservation du
Nouveau-
Brunswick,
déclarait que:
"Une série
d'événements m'a
mené à examiner
l'état de nos
rivières. Cela m'a
mis en colère."

Inka parle de
Rachel Carson et
de son livre 
"Rivers of Death"
(Rivières de la
mort). Elle affirme
que des mesures
draconiennes
doivent être mises
en vigueur si nous
voulons sauver la
faune de nos
rivières.

Rivers of Death Revisited
A Tribute to Rachel Carson 

by Inka Milewski,
Marine Biologist & Director of the
Conservation Council of N.B.
June, 2000, EcoAlert

n 1962, Rachel Carson brought the world’s attention to the toxic and persistent effects of pesticides like DDT on wildlife and humans through her landmark book, Silent Spring. She documented the devastating effect aerial spraying of DDT had on Atlantic salmon, trout, and aquatic insects in the Miramichi and other rivers in the United States. In New Brunswick, aerial spraying of DDT to control spruce bud worm began in 1952. Not only did fish and insects die from immediate (acute) exposure to these chemicals, but, Carson identified DDT’s potential to cause long-term (chronic) effects on sexual development, cell division, and genetic replication. At the time, neither the carcinogenic nor the endocrine disrupting effects of DDT were confirmed.

(photo:NBEN-RENB)

For her effort to draw attention to these problems, she was mercilessly attacked and vilified by the chemical industry. A short time after Silent Spring was published in 1962, U.S. president Kennedy set up a special science advisory panel to study the problems associated with pesticide use. The panel’s report a few months later confirmed Rachel Carson’s findings. It would take another 5 years before aerial spraying of DDT would cease in New Brunswick and 28 years before the Canadian government would completely ban the use of DDT.

DDT was only the first of many pesticides sprayed in New Brunswick. In fact, New Brunswick’s forests and waterways were subject to the longest and most extensive aerial pesticide spray program in the world (Environment Canada, 1989). A very conservative estimate of the amount of pesticides used between 1952 and 1990 to combat spruce budworm is 100,000 mt (220 million pounds). The annual amount of DDT sprayed from 1952 to 1967 was 5,700 mt (12.5 million pounds) (Environment Canada 1991).

DDT was replaced in 1968 by a variety of pesticides. Between 1968 and 1979, approximately 4,000 mt of organophosphates (primarily fenitrothion) were used. Organophosphates affect the transmission of nerve impulses and are very poisonous in very minute amounts. Unlike DDT, organophosphates readily decomposed and are less persistent. Between 1975 and 1985 a carbamate pesticide with the trade name Matacil® was used. What was known about carbamates at the time was their mutagenic affect - their ability to change genes and damage chromosomes and cause mutations. What was not known at the time was that the solvent (4-nonylphenol), which was three times the weight of the active ingredient in the pesticide formulation, was an endocrine disrupting compound. Between 1975 and 1986, a total of 19.392 million hectares of forests in New Brunswick were treated with pesticides (Environment Canada, 1991). The only other province that came close to that figure was Quebec with 13.7 million ha followed by Newfoundland with 0.598 million ha, Nova Scotia with 0.22 million ha, and Ontario with .28 million ha

It is difficult to imagine that this long and sustained rain of pesticides has not had an impact on the overall health of wildlife and human populations. Nowhere is that effect more evident than in the decline of Atlantic salmon in the Miramichi River - a decline which began with the first spraying of DDT in 1952 and continues to this day. In 1952, Rachel Carson called the Miramichi and other rivers subject to DDT spraying - rivers of death. Today, the Miramichi continues to be a river of death for Atlantic salmon and other fish species. At the mouth of the Miramichi River, effluent from the pulp and paper mill, plywood mill, groundwood mill, leachate from former and current industrial chemical dumps, and sewage outfalls create a formidable soup of chemicals through which fish must pass on their way up the river or out to sea. In addition, while magnitude of pesticide spraying has decline, herbicides are still sprayed to control "nuisance" vegetation in upper reaches of the Miramichi watershed.

Recent research demonstrates that a key contaminant in that chemical soup is endocrine disrupting compounds (EDCs) - compounds which do not outright kill a fish but affect the fish’s behaviour, compromise its immune system, alter its reproductive capacity, and reduce its overall fitness. EDCs have been linked to disorders in human sexual development and reproduction and include such compounds as DDT, DDE, dioxin, furans, and PCBs. EDCs are potent at levels much lower than the allowable limits of exposure set by current government standards.

(photo: Rachel Carson Institute)

=========== Rachel Carson ===========

Over the last 40 years many, many efforts have been made to save the Atlantic salmon. Hundreds of millions of dollars have been spent on Atlantic salmon hatcheries, enhancement programs, and research. Over the last 30 years, there have been over 10,000 primary scientific research publications devoted to Atlantic salmon biology, ecology, and management. Still the salmon continue to decline. There are renewed calls for more money and more research to explain the "mystery" in the decline of Atlantic salmon in New Brunswick.

Until the basic quality of the freshwater that salmon and other aquatic species live in is addressed, no amount of research is going to help the Atlantic salmon - that fact has been amply demonstrated. We know the major point sources of current contaminants - they are pulp mills, sewage plants, and aerial herbicide and pesticide spray programs. We need to work to eliminate these sources of contaminants from waterways.

Rather than spend more money on research, a more strategic and immediately effective use of funds would be to assist municipalities in upgrading sewage plants that dump their effluent in waterways and to assist industry in making technological improvements that would reduce the discharge of harmful substances to zero. Groups concerned with the fate of Atlantic salmon and other aquatic wildlife should be lobbying federal and provincial governments that issue permits for the discharge of compounds known to be harmful to fishes and other wildlife for stricter enforcement and higher standards on chemical discharges. Until that happens, the Miramichi and other rivers will continue to be "rivers of death" for salmon.

(photo: DOE)

Carson, R. 1962. Silent Spring. Houghton Mifflin, New York.

Environment Canada. 1989. Environmental Effects of Fenitrothion Use in Forestry: Impact on insect pollinators songbirds & aquatic organisms. W.R. Ernst, P.A. Pearce and T.L. Pollock (Eds). Minister of Supply and Services (Ottawa).

Environment Canada. 1991. The State of Canada’s Environment - 1991. Environment Canada. Minister of Supply and Services (Ottawa).