Introduction:
Aquaculture is the fastest growing
sector of the world food economy but has proceeded way in advance
of environmental and public health safeguards. Chile, in
particular, has experienced phenomenal economic growth (Barton:
1997, 1998a) at the expense of environmental concerns (Hardy:
1994, Buschmann et al: 1996, Barton: 1998b, Hutchison: 1998,
Claude: 2000, Franklin and Woods: 2001, Martinez: 2000, Langman:
2002). The threats identified in the 1970s and 1980s (Odum: 1974,
Ackefors and Rosen: 1979, Beveridge: 1984, Earll et al: 1984,
Luxmore: 1984) have been systematically ignored by Governments
around the world intent on protecting and promoting aquacultural
expansion rather than consumer and environmental protection. The
lessons learned in Norway and Scotland, for example, are being
ignored as the same companies make the same environmental mistakes
in different areas of the world economy. So much so that
aquaculture and farmed fish products now represent a global threat
to both the marine environment and consumer safety (WHO: 1999).
Sea cage salmon farming presents insurmountable global
environmental problems in terms of mass escapes, the spread of
infectious diseases, parasite infestation, the reliance upon toxic
chemicals, contamination of the seabed and the discharge of
untreated waste effluents (ICES: 1996, Sierra Legal Defence Fund:
1997, Weber, 1997, ICES: 1999, Black: 2001, Milewski: 2001,
Philippine Daily Inquirer: 2002).
Government inquiries in Canada
(Environment Assessment Office: 1998) and Scotland (Berry: 2000,
Scottish Executive: 2000, Staniford: 2001b, Scottish Parliament:
2002 ) as well as NGO initiatives such as the ‘citiziens
inquiry’ organised in British Columbia (Leggatt: 2001) or the
‘parliament of the sea’ in Chile (Ecoceanos: 2001a) have
focused public attention. NGO reports in Chile (Claude: 2000,
Ecoceanos: 2002), the United States (Goldburg and Tripplett: 1997,
Goldburg et al: 2001), Ireland (O’Brien: 1989, O’Sullivan:
1989, Meldon: 1993), Canada (Ellis: 1996, Milewski et al: 1997,
Friends of Clayoquot Sound: 1998) and Scotland (Bishop: 1987,
Ross: 1997, Berry and Davison: 2001, Staniford: 2001a, Lymberry:
2002) have all raised awareness of the environmental impacts of
salmon farming. All have served to open up the debate concerning
the future of fish farming (Charron: 2000, Seaweb: 2002) and have
led many commentators around the world to question the very
legitimacy of salmon farming (Newswatch Canada: 1994, Hide: 1996,
Morton: 1996, Hutchison: 1998, Lindbergh: 1999, Ride: 2000, Wigan:
2000, Babcott: 2001, Blythman, 2001, Bristow: 2001, Franklin and
Woods: 2001, Galvin: 2001, Gibb: 2001, Girling: 2001, Miller:
2001, Orr: 2001, Stanley: 2001, Tabak: 2002, The Economist: 2001,
The Steelheader: 2001, Langman: 2002, Hamilton-Paterson: 2002,
Hunt: 2002, Salt Spring News: 2002). Whilst there are undoubtedly
many examples of responsible and sustainable aquaculture open sea
cage finfish farming is surely not one of them (Folke and Kautsky:
1989, 1992, Holdgate: 1995, Reinertsen and Haaland: 1995, Wu:
1995, Naylor et al: 2000, Black: 2001, Tacon and Barg: 2001,
Tidwell and Allen: 2001, Cripps: 2002, Roth et al: 2002). Any
industry which is reliant upon a fast-diminishing fisheries
resource to fuel its own expansion and which discharges untreated
contaminated wastes directly into the sea affecting other coastal
users is hardly sustainable. And the potentially fatal sting in
the tail is that farmed salmon contains high levels of
contaminants such as dioxins and PCBs (Jacobs: 2000, Wigan: 2001,
Easton: 2002). In so many ways, the phrase ‘sustainable salmon
farming’, like so-called ‘organically farmed salmon’ is an
oxymoron (Staniford: 2001c).
From family to factory fish farming:
Sea cage fish farming has ushered in
a new era of resource exploitation which is both irresponsible and
unsustainable. Over thirty years ago the environmental economist
Garrett Hardin (1968) predicted that:
“The fish populations are
exploited as commons, ruin lies ahead….only the the replacement
of the commons with a responsible system can save oceanic
fisheries”
Far from being a panacea for the
decline in wild fisheries, sea cage salmon farming has compounded
the crisis. Indeed, the term ‘responsible aquaculture’ (Tacon
and Barg: 2001) is a foreign country in today’s world of salmon
farming. As fish have become privatised multinational
monopolisation and monocultural intensification, the last two
decades has seen a fundamental shift away from ‘family’
towards ‘factory’ fish farming and a marked transition from a
capture to a culture economy (Aitken and Sinclair: 1995, Williams:
1996). In 1984 aquaculture accounted for only 8% of fisheries
production leaping to ca. 25% in 2001 and by 2020 aquaculture is
predicted to have overtaken capture fisheries. This is already the
case for salmon where farmed production was 1.1 million tonnes in
2000 compared to a wild catch of 723,000 tonnes (Berge: 2001,
Berge: 2002). World salmon farming production is predicted to
double to over 2 million tonnes in 2010 (in 1996 it was 600,000
tonnes and only 50,000 tonnes in 1985) (Intrafish: 1999). Global
expansion has been fuelled by fewer but larger companies.
Norwegian and Dutch multinationals dominate the salmon farming
sector in Chile, Scotland, Ireland and Canada (Jensen: 2000). In
2000, the 30 largest salmon farming companies in the world
achieved a total production of 666,300 tonnes (expected to rise to
959,000 tonnes in 2001), accounting for ca. 60% of the world’s
total farmed salmon production (Berge: 2001). Nutreco (Nutreco:
2001a, 2001b, Nutreco: 2002), twice as big as the next on the
list, is the world number one with Cermaq, Fjord Seafood and
Domstein merging in May 2002 to become the second largest (Berge:
2002). Such is the stranglehold of multinationals that four
companies now control over 80% of the world’s salmon feed market
(Charron: 1999). Intrafish describes the situation as “almost
incestuous with so many merger talks and buyouts in the global
aquaculture industry” (Berge: 2001). Nutreco, which has “vast
untouched resources in Chile” estimated at 200,000 tonnes (Berge:
2001), has been heavily criticised with strikes in Chile last year
(Carvajal: 2001, Ecoceanos: 2001c, Nutreco: 2001a), a 15% fall in
its share price following reports of high levels of dioxins in
farmed salmon (Intrafish: 2001a) and an ‘Earth Alarm’
investigation by Friends of the Earth Netherlands (Milieudefensie:
2001). Today, a single farm can cover many hectares of coastal
area and raise up to one million fish on a site (Milewski: 20010.
The ecological footprint is now so large that salmon farming is
far too big for its boots (Folke et al: 1998, Martinez: 2000,
Naylor et al: 2000, Thomas: 2001).
The false economy of sea cage fish
farming:
Farming carnivores such as salmon,
halibut, cod, sea bass, sea bream and tuna so high up the food
chain is a case of ‘robbing Peter to pay Paul’. According to
Dr Daniel Pauly (Thomas: 2001), speaking at last year’s American
Association for the Advancement of Science conference:
“The new trend in aquaculture is
to drain the seas to feed the farms. Meanwhile capture fisheries
now focus on what we once considered bait. These two trends -
farming up and fishing down the food web - imply massive impacts
on marine ecosystems that are clearly unsustainable”
Given the net loss in fisheries
resources it is no wonder fishermen feel short-changed and are
increasingly questioning the impact of fish farming expansion on
the fisheries sector (Butler et al: 2001, Cameron: 2001d, The
Fishermen’s Voice: 2001, Hunt: 2002). Since both parties are
pulling in opposite directions - one farming up and one fishing
down the food chain - such a clash of cultures will inevitably
have global repercussions. A paper in the scientific journal
Nature (Naylor et al: 2000) has calculated that over 3 tonnes of
wild fish are required to produce one tonne of farmed salmon, for
example (for other marine fish this rises to over 5 tonnes) [1].
Farming salmon is like farming tigers and has been described as
‘biological nonsense’ (Goldburg and Tripplett: 1997). On land
we only farm herbivores such as cattle, pigs, sheep and chickens
so why do we not apply the same principles when farming in the
sea? Sadly, common sense is not a currency those bankrolling
salmon farming are used to dealing in. When all the environmental,
economic and social costs are internalised, sea cage fish farming
makes precious little sense at all (Folke et al: 1994, Ellis:
1996, Folke et al: 1997, Naylor et al: 1998, 2000, Lindbergh:
1999, Claude: 2000, Tyedmers: 2000, The Economist: 2001, Tidwell
and Allen: 2001). By not paying for waste disposal salmon farmers
are effectively freeloading on the coastal marine environment.
Integrated salmon farming and seaweed cultivation, for example,
can partially offset some of the environmental costs (Troell et
al: 1997) but it is difficult to escape the conclusion that this
represents anything other than a net deficit (Barton and Staniford:
1998). Similarly, the inclusion of shellfish and seaweeds into a
salmon farming system (Folke and Kautsky: 1989, Sota and Medena:
1999, Chopin et al: 2001) may ameliorate the waste problem but the
industry’s reliance upon toxic chemicals makes shellfish farming
alongside salmon incompatible.
Salmon farming is running on empty -
it is literally running out of fuel (Bishop: 1987, Naylor et al:
2000, Tacon and Forster: 2000, Jystad: 2001, Hjellestad: 2001a,
2001b). Such is aquaculture’s appetite for seafood that it
already consumes ca. 75% of the world’s fish oil and ca. 40% of
the world’s fish meal (IFOMA: 1990a, 1990b, Pike and Barlow:
1999). The International Fishmeal and Oil Manufacturers
Association predict that by 2010 aquaculture could consume 56% of
the world’s fishmeal and 90% of the world’s fish oil (Charron:
1999, Pike and Barlow: 1999). According to to the Food and
Agriculture Organisation, by 2010 salmon and trout alone could
consume 620,000 tonnes of fish oil (Jystad: 2001). Like crude oil,
fish oil - the new blue gold - has become a key commodity in the
world economy with demand outstripping supply and rising prices (Hjellestad:
2001b, 2001c, Staniford: 2001b). Fisheries resources are becoming
so scarce and so expensive that salmon companies are stockpiling
fish feed and investing in fishing fleets to catch fish
themselves. In June last year the Research Council of Norway,
where a staggering 80% of all fish caught by Norwegian trawlers is
used to provide feed for the fish farming industry, predicted that
“within three to eight years the lack of marine oil raw
materials could hinder the growth of Norwegian salmon farming” (Hjellestad:
2001a). Not only is this fuel supply fast running out but also the
remaining fish is contaminated with dioxins, poly-chlorinated
bi-phenyls (PCBs) and organochlorine pesticides (Jacobs et al:
1997, 1998, 2000, 2002). Hence the increasingly desperate search
for alternatives such as soya, seaweeds, krill and plankton (Jystad:
2001, Sinnott: 2002). The Institute of Marine Research in Norway
explains how PCB contamination in fish meal has led them to seek
substitutes further afield in the Arctic and further down the food
chain in the shape of krill:
“PCB accumulates in fish, so there
is more PCB higher in the food chain. That means that there is
less PCB in krill, which is lower in the food chain” (Hjellestad:
2002)
Fish diets, especially those high in
fish oils and fish meal, have also been linked to eutrophication
(Talbot and Hole: 1994) and pollution (Johnsen and Wandsvik: 1991,
Johnsen et al: 1993, Tacon: 2002). The substitution of fish feed
with vegetable diets has been shown to have less of a waste impact
on phytoplankton and hence on pollution (AQUATOXSAL: 2002) but
salmon fed on vegetables is not to everyone’s taste. For
example, after a consignment of Norwegian farmed salmon was sent
back by Japan, the managing director of the Nutreco fish feed
company Skretting said that ‘the increased use of vegetable oil
as an ingredient in fishfeed is suspected as a potential reason
for the funny taste of the product’ (FIS: 1999). Similar
problems with taste have been encountered with farmed cod (Fossbakk:
2001) and there really is no substitute for wild fish. Any amount
of technical tinkering (Sinnott: 2002, Smith: 2002) will not alter
the fact that turning a carnivore into a herbivore is doomed to
failure (Naysmith: 2001a). Salmon farming is like an oil tanker,
leaving a trail of toxic waste in its wake, heading for the rocks.
Unless it changes course immediately it will sink as quickly as it
first reared its ugly head.
Cancer of the coast:
Salmon farming’s capacity to foul
its own nest is no more so apparent than in the lochs, bays,
loughs, fjords and inlets around the coasts of Norway, Scotland,
Ireland, British Columbia, New Brunswick, Maine, the Faroes,
Tasmania, New Zealand and Chile. Norway is the world leader (ca:
450,000 tonnes) but Chile (ca: 400,000 tonnes) is fast closing the
gap with Scotland (ca. 160,000 tonnes) ranked in third place. The
rapid rise of Chilean farmed salmon in export markets has been
described as the “Chilean invasion” (Berge: 2002) yet it has
been fuelled predominantly by Norwegian companies (Jensen: 2000).
Production in Chile, for example, is expanding so fast that
exports of salmon and trout between January and March this year
were 116,256 tonnes (Arias: 2002). The waters off China,
Argentina, South Africa and France are next the multinational’s
shopping list but these countries should think twice before
allowing salmon farms to pollute pristine coastal waters. In
Canada (Hellou: 2002a, 2000b) and Scotland (Pirie: 2001, SEPA:
2001a) research has shown high levels of PCBs, DDT and alkylated
polycyclic aromatic hydrocarbons (PAHs) in the sediments under
salmon cages. The build-up of bacteria under cages (at up to 10
times the background environment) can also affect the health of
the salmon themselves (Brown et al: 2000). The cocktail of toxic
chemicals used on salmon farms jeopardises not only the marine
environment but also the safety of workers (Douglas: 1995, GESAMP:
1997, Kelleher et al: 1998, Connolly: 2002). Chemicals used on
salmon farms include carcinogens, mutagens and a myriad of
‘marine pollutants’. The decision to licence them is based
more on economic expediency than consumer safety and is tantamount
to state-sponsored pollution (Merritt: 2002).
Other threats include the
interbreeding of wild salmon and farmed escapees (Clifford et al:
1998, Youngson et al: 1998, Hansen et al: 1999, Fleming et al:
2000, Galvin: 2001, Volpe: 2001), impacts on cetaceans (Morton and
Symonds: 2001), sea lice infestation (Edwards: 1998, Butler: 2001,
Watershed Watch: 2001, Bjorn and Finstad: 2002, Butler: 2002) and
the spread of infectious diseases such as Infectious Pancreatic
Necrosis (IPN) and Infectious Salmon Anaemia (ISA) to wild
fisheries (McAllister and Bebak: 1997, FoCS: 1998, Murray: 1999,
McCarthy: 2000, Paone: 2000b, Cameron: 2001c, Royal Society of
Edinburgh: 2001). ISA outbreaks have been recorded since 1998 in
Scotland, Maine, the Faroes and Norway where the situation is
described as “worse than ever” (Solsletten: 2001). In Canada
this year an outbreak of Infectious Hematopoietic Necrosis (IHN)
led to over one million fish being slaughtered (4 million salmon
were slaughtered during the ISA outbreak in Scotland). In May a
deadly new parasite was discovered at a salmon farm in Northern
Norway threatening one of the best Atlantic salmon rivers in
Europe (Intrafish, 2002b). An obvious way of spreading diseases,
parasites and genetic pollution is via escapes. There have been
over 1 million reported escapes from fish farms in Scotland alone
since 1997 with an estimated 5 million in Norway over the last
decade. In the Faroes in February this year 600,000 salmon escaped
(Intrafish: 2002a) in what is believed to be the largest escape
anywhere in the world and escapes are such a problem that in
British Columbia Atlantic salmon are now breeding in the Pacific
(Needham, T: 1995, Volpe et al: 2000, Volpe et al: 2001) and have
been caught in Alaskan waters. Any Atlantic salmon caught in Chile
will also be escapees. Nor does the introduction of GM technology
(GM salmon trials have already taken place in New Zealand,
Scotland, Canada and Chile) augur well for the future (Van Acken:
2001, Solar: 2002). And the replacement of contaminated fish meal
and fish oil in the diets of farmed salmon with GM soya will
inevitably meet with consumer resistance, especially in Europe (Jystad:
2001). Welcome to the brave new world of 21st century fish.
Chemical culture:
Flooding coastal waters with a
cocktail of toxic chemicals is the antithesis of the precautionary
principle (Ross: 1989) and highly questionable under international
environmental law (OSPAR: 1994, GESAMP: 1997). For example,
despite a background of increasing environmental and public health
concerns (PAN: 1997, DETR: 1998, Rodger: 1999, Davies et al: 2001,
Zitko: 2001), the Scottish Environment Protection Agency (SEPA)
has opened the floodgates to chemical use on salmon farms (Redshaw:
1995, SEPA: 1997, SEPA: 1998a, Carrell: 2000, Rae: 2000). Since
1998 the UK Government have approved over 700 chemical licences
for cypermethrin (trade name Excis), azamethiphos (Salmosan),
teflubenzuron (Calicide) and emamectin benzoate (Slice) (Merritt:
2002). Even before 1998 the UK aquaculture industry was hooked on
a wide range of toxic chemicals including dichlorvos, ivermectin
and antibiotics (Rae: 1979, Ross: 1990, Davies: 1991, SWCL: 1992,
SWCL: 1993). A typical discharge consent issued by SEPA to salmon
farmers permits the use of over 50 different chemical formulations
including antiparasitics, antibiotics, antifoulants and
disinfectants and the number of ‘medicines’ licensed for use
on salmon farms by the Veterinary Medicines Directorate increased
from 3 in 1989 to ca. 40 in 2002 (Henderson and Davies: 2001).
Since Scotland is acknowledged as the most difficult country to
secure approvals (Cameron and Charron: 2001), chemical consumption
in other salmon farming countries such as Norway, Canada and Chile
may be even higher. In the Scottish Parliament questions
concerning the exact quantities of chemicals used remain
unanswered (Cameron: 2002a). Other requests for chemical data have
been denied by either the Government or the chemical companies
concerned but figures that are available are alarming. According
to the Scottish Government (Scottish Office: 1992) the annual use
of chemicals in 1989 was as follows: Chloramine-T (1.5-2 tonnes),
formaldehyde (14 tonnes), vaccines (2,400 litres), iodophors (5
tonnes), furazolidone (0.2 tonnes), ethoxyquin (4-5 tonnes),
dichlorvos (20-50 tonnes), sulphadiazine and trimethroprim (0.2 -
0.3 tonnes), oxolinic acid (8-10 tonnes), oxytetracycline (8-10
tonnes), malachite green (1.5 tonnes), canthaxanthin (1.5-2 tonnes),
astaxanthin (1.5-2 tonnes), copper oxide (small) and
methyltestosterone (0.1 gram). Since 1989 the Scottish salmon
farming industry has increased five-fold.
Elsewhere in Canada (Burridge and
Haya: 1995, DFO: 1996, Ellis: 1996, CCNB: 1998, Environmental
Assessment Office: 1998, Ernst et al: 2001) and Norway (Grave et
al: 1991, DNM: 1999, Grave et al: 1999, Horsberg: 2000, ICES:
1999, FIS: 2001) a global picture of drug abuse in salmon farming
is becoming clearer. In Chile, certainly in the mid-1990s,
diseases were controlled “mainly by an increasing and often
indiscriminate use of antibiotics” (Hide: 1996). Moreover:
“An international survey revealed
that eleven compounds representing five pesticide types are
currently being used on commercial salmon farms for sea lice
control. These include two organophosphates (dichlorvos and
azamethiphos); three pyrethrin/pyrethroid compounds (pyrethrum,
cypermethrin, deltamethrin); one oxidizing agent (hydrogen
peroxide); three avermectins (ivermectin, emamectin and doramectin)
and two benzoylphenyl ureas (teflubenzuron and diflubenzuron). The
number of compounds available in any one country is highly
variable, ranging from 9 (Norway) to 6 (Chile, United Kingdom) to
4 (Ireland, Faeroes, Canada) to 2 (US). Dichlorvos, azamethiphos
and cypermethrin were the most widely used compounds (5 countries)
followed by, hydrogen peroxide, ivermectin and emamectin (4
countries each), teflubenzuron (3 countries), diflubenzuron (2
countries), and deltamethrin, pyrethrum and doramectin (1 country
each), although, like trichlorfon, dichlorvos use is being
discontinued in several countries notably Norway and the
Faeroes” (Roth: 2000)
In Norway, as dichlorvos use slowed
down a new suite of chemicals such as azamethiphos, praziquantel,
fenbendazole, diflubenzuron, deltamethrin, emamectin and
teflubenzuron took its place (Horsberg: 2000). Salmon farming is
locked into a chemicals arms race (Sommerville: 1995), be it
legally via state-sponsored pollution or via salmon farmers using
toxic chemicals such as ivermectin and cypermethrin (both often
referred to as “jungle juice” or “horsey stuff”)
illegally. In Shetland the problem is so visible that chemical
containers have been washed up on the beach (SEPA: 2001b). Nor are
Scottish salmon farmers the only ones guilty of using toxic
chemicals illegally (SEPA: 1998b, Barnett: 2000, BBC: 2000, FoE:
2000, SEPA: 2002, VMD: 2002). Salmon farmers in Norway (Jensen:
2001), the United States (Ernst et al: 2001) and Chile (Franklin
and Woods: 2001) have all been caught out. As SEPA stated:
“There is some illegal use of
cypermethrin in Canada, often at night using high concentrations
and no tarpaulin. There has been some alleged illegal use of
cypermethrin products in Shetland using compounds which contain
persistent aromatic hydrocarbons” (SEPA: 1997)
Most of the chemicals used on salmon
farms to kill sea lice also kill other sea life (Edwards: 1996)
and some are so toxic that they can cause cataracts in farmed
salmon (Fraser et al: 1989, Fraser et al: 1990). Shellfish farmers
have expressed concern over the use of chemicals (MacLeod: 2000,
Ross and Holme: 2001) and some even have disruptive effects on the
reproduction of wild Atlantic salmon (Moore and Waring: 2001).
Azamethiphos, cypermethrin, teflubenzuron and emamectin are all
labelled as “marine pollutants” on the chemicals manufacturers
Safety Data Sheets. Unsurprisingly they do exactly what they say
on the tin. It hardly takes a rocket scientist to work out that
“marine pollutants” pollute the marine environment (Staniford:
2002). The European Medicines Evaluation Agency, for example,
openly conceded that “the proposed use of Azamethiphos in fish
farming means that deliberate contamination of the environment
will occur” (EMEA: 1999). SEPA have also admitted that
azamethiphos is ten times more toxic than another organophosphate,
dichlorvos (SEPA: 1997) and Canadian research has also shown toxic
effects of azamethiphos and cypermethrin on lobsters (Burridge et
al: 2000). Cypermethrin has recently been shown to have
“area-wide effects” on sensitive species such as shellfish
(Ernst et al: 2001) and significant impacts on salmon’s sense of
smell (Moore and Waring: 2001). An ongoing Government-sponsored
study by the Scottish Association of Marine Science also
highlights the potential risks of the sea lice chemicals such as
teflubenzuron and emamectin (Natural History Museum: 1997,
Scottish Association of Marine Science: 2002a, 2002b, Edwards:
2002b). Early indications are that “teflubenzuron and emamectin
causes mortality and deformity at very low concentrations” and
“that sea lice chemicals may exert significant ecological
effects at concentrations well below indicative LC50 values and
after only brief exposures” (SAMS: 2002b). The project, part of
which has been plagued by problems including logistical
difficulties between scientists and salmon farmers (Edwards:
2002b), states that:
“The chemicals used to control sea
lice are highly toxic to crustaceans, and are used by the salmon
farming industry because of their efficacy at killing certain life
stages of the parasitic copepods. The little data available on the
toxicity of sea lice chemicals to planktonic copepods is confined
to less ecologically relevant species. Because planktonic copepods
have a similar life cycle to parasitic copepods they are also
likely to be adversely affected. Copepods are of prime importance
in marine ecosystems and numerically dominate in the zooplankton.
They form the base of virtually all pelagic food chains and
provide the link between phytoplankton and fish. The toxicity of
three sea lice treatment chemicals, cypermethrin, emamectin
benzoate and teflubenzuron, to common planktonic copepods is being
investigated using laboratory bioassays and in situ exposures” (SAMS:
2002b)
In the meantime, however, there is a
dearth of environmental information in the public domain on the
more recent chemicals such as emamectin benzoate (Stone et al:
2000) and teflubenzuron (Anon: 2000, Trouw Aquaculture: 2000).
Nutreco have undertaken a project in conjunction with the Scottish
Association of Marine Science, for example, on the impact of
Calicide (teflubenzuron) on sea urchins but this remains
unpublished (SAMS: 2001) and requests for further information have
been refused on grounds of ‘commercial confidentiality’.
Figures produced by Nutreco, the manufacturers of Calicide, help
explain why such documents are not yet in the public domain: 90%
of the parent compound (teflubenzuron) is excreted via faeces with
high levels still detected some 18 months after chemical treatment
(Nutreco: 1998). Other scientific papers on the environmental
impact of Calicide remain ‘private and confidential’
(Institute of Aquaculture, McHenery: 1999, Ritchie: 1999). The
Association of Scottish Shellfish Growers, who voted in 2001 for a
moratorium on the expansion of salmon farming (Ross and Holme:
2001), said that “Calicide is one chemical too far for the
marine environment in general and shellfish interests in
particular” (MacLeod: 2000). Instead SEPA have approved over 100
licences for the use of Calicide.
Judging by the time lag between the
use of chemicals such as ivermectin (Duffus: 1996a, Davies et al:
1998, Grant and Briggs: 1998a. 1998b, Cannavan et al: 2000), TBT
(Balls:1987, Davies et al: 1998), azamethiphos (Gillibrand and
Turrell: 1999, Abgrall et al: 2000, Ernst et al: 2001),
cypermethrin (Ernst et al: 2001, Moore and Waring: 2001) and
dichlorvos (Dobson and Tack: 1990, Wells et al: 1990, Murison et
al: 1997, McKeown and Hay: 1998) and scientific publication it may
be a decade until these risk assessments enter the peer-reviewed
public domain. Since ‘commercial confidentiality’ often
precludes publication, for the time being at least, any
environmental risk assessments of the latest chemicals remain
unpublished or ‘private and confidential’ (e.g Natural History
Museum: 1997, Nutreco: 1998). Even reports dating back over ten
years are still not in the public domain as the chemical companies
concerned have either refused to publish them (Ciba-Giegy: 1987a,
1987b, 1988a, 1988b, 1988c, Duffus: 1996a, McHenery: 1999,
Ritchie: 1999) or the UK Government, for example, have deemed them
‘Security Level 1’ documents out of reach of the general
public (e.g Davies: 1991, Seafish Industry Authority: 2001). Other
UK Government reports are so confidential the name of the chemical
is given a security code instead of a name (Madden et al: 1992a,
1992b, McHenery: 1991a, 1991b, Callahan et al: 1992) or the
documents are “not to be quoted without prior reference to the
authors” (e.g Murison et al: 1990, Wells et al: 1990, Robertson
et al: 1991, Scottish Office: 1992, McKeown and Hay: 1998,
Gillibrand and Turrell: 1999). Such is the pervasive culture of
secrecy in Scotland (Bristow: 2001, Edwards: 2001a, 2001b).
The most blatant example of the
failure to control chemical discharges from salmon farms is the
organophosphate pesticide dichlorvos (Ross and Horsman: 1988,
Ross: 1990, Edwards: 2002a) which is also known as ‘Nuvan’,
‘Aquagard’ or ‘Neguvon’ (in fly spray killers it goes by
the catchy trade name ‘Doom’). In Scotland, trials of
dichlorvos, which involved dangling dichlorvos fly-strips into the
salmon cages, were conducted by Unilever in Loch Ailort in 1976
(Rae: 1979, Saward et al: 1982) and despite an increasing body of
research showing both environmental and public health concerns (Stanislawska-Swiatkowska
and Ranke-rybicka: 1976, Ross and Horsman: 1988, Murison et al:
1990, Murison et al: 1997, EPA: 2000) dichlorvos use on salmon
farms in Scotland continued throughout the 1980s and 1990s (Novartis
- formerly Ciba-Giegy withdrew the licence in November 1999). In
Norway and the Faroes, the use of dichlorvos (and trichlorfon
which degrades into dichlorvos) was discontinued in the mid-1990s
(Roth: 2000) but ca. 7 tonnes were used in 1989 (ICES: 1999,
Horsberg: 2000). The UK’s Department of the Environment
estimated in 1991 that “10-20 tonnes” of dichlorvos (up to 5
times all other household, pest control and agricultural uses
combined) was used annually on Scottish salmon farms (DoE: 1991)
and the Scottish Office calculated that “20-50 tonnes” were
used in 1989 (Scottish Office: 1992). SEPA admitted this year that
many licences to use dichlorvos are still active (Edwards: 2002a,
Cameron: 2002b). So many litres of dichlorvos were poured into
Scottish lochs that by the 1990s sea lice developed resistance
(Jones et al: 1992).
Dichlorvos was also used extensively
in Ireland (Tully and Morrissey: 1989) where a former worker with
testicular cancer is now taking legal action (Connolly: 2002),
Chile (SEPA: 1999a, Kent: 2000) and Norway (Samuelsen: 1987, Grave
et al: 1991, Horsberg: 1999) with trials taking place in Canada (Cusack
and Johnson: 1989, Castledine and Armstrong: 1990). In Norway, the
quantities of dichlorvos used were so high that fatal
organophosphate poisoning of the farmed salmon took place (Salte
et al: 1987, Horsberg et al: 1989) and residues were detected in
the flesh of the salmon (Horsberg and Hoy: 1990). In Canada, it
was discovered that the dichlorvos pesticide formulation Aquagard
(manufactured by Ciba Giegy), which consists of the solvent
di-n-butyphthalate is more toxic to juvenile Atlantic salmon that
the active ingredient dichlorvos alone (Burridge and Haya: 1995).
Following on from evidence gathered by the US Environmental
Protection Agency (EPA: 20000), in July 2001 the Department of
Health’s Committee on Mutagenicty in the UK finally published
evidence that dichlorvos was carcinogenic (DoH: 2001) and in April
2002 the UK Government eventually banned the use of dichlorvos (DEFRA:
2002). As late as 1998 human trials of dichlorvos were being
conducted in England on behalf of the American chemical company
AMVAC (EWG: 1998, Walth and Pulaski: 1999). A study on the
leukemia, lymphoma and testicular tumours in Western Ireland
“found a significant increase in testicular tumours in
agricultural workers other than farmers, albeit with very small
numbers; this group comprised predominantly those engaged in fish
farming” (Kelleher et al: 1998). Further studies are urgently
required in other salmon farming coutries where dichlorvos use has
been widespread. As yet:
“There is no evidence to date of
an increase in this category of testicular malignancies in fish
farm workers in other countries that retain adequate occupational
surveillance data and have a significant fish farm industry such
as Scotland and Scandinavia and there are no confimatory studies
of tumours among the fish themselves, though potential toxicity to
Nuvan, the principal agent used to control sea lice infestation
has been studied at varying concentrations” (Kelleher et al:
1998, 656)
In Scotland, Norway, Ireland and
Chile it seems salmon farmers have been blindly participating in a
25 year trial. Successful legal action in Ireland (Connolly: 2002)
could open the floodgates to similar compensation claims.
The UK’s Committee on Mutagenicity
also published evidence showing malachite green was mutagenic in
1999 (Department of Health: 1999, Worldcatch: 2000, Carrell:
2001a). Malachite green has been used extensively, be it legally
or illegally, in the UK (Alderman: 1985, Alderman: 1997), Norway
(Jensen: 2001) and Chile (Franklin and Woods: 2001) for over 15
years and just last year was detected by the Veterinary Medicines
Directorate in farmed salmon on sale in UK supermarkets (VMD:
2002). The same body also found PCBs in farmed salmon imported
from Chile and Norway and in farmed trout from Denmark (Cameron:
2002c, VMD: 2002). Residues of chlordane, toxaphene, cadmium, DDT,
dieldrin, oxytetracycline and dioxins have all been found in the
flesh of farmed salmon. Copper and zinc from the excessive use of
antifoulants have also been detected in sediments at over 20 times
the safety limits (SEPA: 1998d) and the abuse of antibiotics has
also left its mark (Capone et al: 1996). So extensive is the use
of the artificial pigment canthaxanthin (Prodanou: 2001) that
escaped salmon and fish feeding near salmon cages have been found
containing pink dye (Fisheries Management and Ecology: 2000). And,
rather vividly, “so persistent are these dyes that they tone the
excrement to match” (Girling: 2001). The industry’s purely
cosmetic response has been to call such toxic chemicals
‘vitamins’, ‘medicines’, or ‘chemotherapeutants’.
Ultimately, the policy of
‘chemotherapy’ is doomed to failure and it is certainly not
sustainable (Alderman: 1999). Governments around the globe have
colluded to allow salmon farmers free reign to pollute with
impunity with soaring chemical use in aquaculture (Alderman: 1988,
Meyer and Schnick: 1989, Michel and Alderman: 1992, Costello:
1993, Roth et al: 1993, Schnick et al: 1997, Schnick: 1998, Long:
2000, Rae: 2000, Roth: 2000, Costello et al: 2001, Henderson and
Davies: 2001). Scientists have focused on the efficacy of killing
sea lice to the exclusion of other marine impacts (Raverty: 1987,
Buchanan: 1992, Stone et al: 2000, Toovey and Lyndon: 2000). Lest
it be forgotten that sea lice are crustacea and so too are crabs,
lobsters, prawns and shrimps and therefore chemicals designed to
kill sea lice also have significant effects on other crustacea (Egidius
and Moster: 1987, Murison et al: 1990, Berry: 1992, Burridge et
al: 2000, Ernst et al: 2001). ‘Harmonisation’ of chemicals
regulations is merely a euphemism for global approvals of yet more
chemicals (Schnick: 1992, Armstrong: 1994, Schnick and Smith:
1999) with unknown synergistic effects of such a cocktail of
chemicals. The only safe way of getting off the chemical treadmill
is to start ripping out the salmon cages which have spread like a
cancer around our coasts. A moratorium on salmon farming expansion
(Berry and Davison: 2001, Ecoceanos: 2001b) at the very least is
urgently required. Last year Friends of the Earth Scotland called
for a ‘back to basics’ approach advocating “The 3Rs”:
relocation, revocation and removal (FoE: 2001b). With a legacy of
badly located farms and contaminated sites complete removal may be
a bitter pill to swallow but it is the only sensible and
sustainable solution. Moving cages around a single area (Goudey et
al: 2001) is merely storing up problems for a later date (Pohle et
al: 2001). Many farms in Scotland, for example in Loch Fyne and
Loch Sunart, have been forced to move out of enclosed lochs due to
overproduction (Staniford: 2001). The ‘pollute and move on’
mentality of shifting cultivation in the sea is surely not
acceptable.
Toxic salmon wastes:
The global advance of intensive
salmon farming has meant that farmed fish have become agents of
pollution rather than biological indicators of pollution (Ruokolahti:
1988, Frid and Mercer: 1989, Ross: 1989, Alvial: 1991, Tsutsumi et
al 1991, Wu: 1995, Grant and Briggs: 1998a, 1998b, Ernst et al:
2001). The capacity of fish farms to pollute the freshwater and
inshore coastal environment is well documented (Hinshaw: 1973,
Odum: 1974, Solbe: 1982, Gowen and Bradbury: 1987, Pearson and
Gowen: 1990, Kelly: 1993) but the scale of salmon farming
expansion is such that the wider marine environment is now at risk
(GESAMP: 1996). The carrying capacity of coastal areas to support
sea cage salmon farming (Beveridge: 1984, Barg: 1992) was surely
breached years ago (Folke et al: 1994, 1997, 1998). Salmon farms
have been shown to pollute the area directly under the cages (Earll
et al: 1984, Brown et al: 1987, Braaten et al: 1988, Lumb: 1989,
Lewis and Metaxas: 1991, Hargrave et al: 1993, Black et al: 1994a,
Black et al: 1996, Provost et al: 1997, Intrafish: 2001c, Piker et
al: 2002) but this ‘self-pollution’ can also extend out much
further into coastal waters (BBC: 2002) and over much longer
periods (Nickell et al: 1995, Pohle et al: 2000, Pohle et al:
2001) than predicted by models (Silvert: 1992, Silvert: 1994,
Gillibrand and Turrell: 1997, Silvert and Cromey: 2001, Gillibrand
and Cromey: 2002).
The release of nutrients to the sea
from salmon farms has been increasingly linked to
hypernutrification and eutrophication (Ackefors and Enell: 1990,
Aure and Stigebrant: 1990, Handy and Poxton: 1993, Gowen: 1994,
Folke et al: 1997, Chen et al: 1999, ICES: 1999, Arzul et al:
1999, Edwards: 2000, MacGarvin: 2000, Martin: 2000, Navarro: 2000,
Arzul et al: 2001, Girling: 2001, Arzul: 2002, Dosdat: 2002, SAMS:
2002c, Tett and Edwards: 2002). Chemical wastes from salmon farms
have also been linked to wider toxic effects and phytoplankton
changes (Raine et al: 1990, McKeown and Hay: 1998, Lutzhoft et al:
1999, Haya et al: 2001, SAMS: 2002a) as well as impacts on fish
health (Horsberg and Hoy: 1990, Black et al: 1994b, Moore and
Waring: 2001) and the build up of bacteria (Brown et al: 2000).
Sea cage farms littering the coast are in effect using the marine
environment as an open sewer. In enclosed areas with low flushing
rates this equates to flushing your toilet only once a month. The
untreated effluent, including toxic waste containing chemicals
such as dioxins and PCBs, generated by salmon farms is hardly a
drop in the ocean (Bergheim and Asgaard: 1996, Hennessey: 1996,
SEPA: 1998c, Davies: 2000). A major source of the nitrogen and
phosphorus contamination (and of PCBs and dioxins) is the fish
feed itself (Johnsen and Wandsvik: 1991, Johnsen et al: 1993,
Phillips et al: 1993, Talbot and Hole: 1994, Gavine et al: 1995,
Arzul et al: 2002, Tacon: 2002).
At the European level, salmon farm
wastes are receiving increasing scrutiny (Alabaster: 1982,
Rosenthal et al: 1993, EC: 1995, HELCOM: 2001). The effluent from
Norwegian salmon farms, for example, represents a significant and
increasing part of Norway’s coastal discharges of nitrogen and
phosphorus (Braaten et al: 1983, Enell: 1995, Ervik: 1997, ENDS:
2000, Hansen et al: 2001). According to the Directorate for Nature
Management phosphorus and nitrogen wastes from salmon farms
increased from 2,500 to 3,500 tons and 13,000 to 16,000 tons
respectively (DNM: 1999). It also stated that “in many
countries, the aquaculture industry is the greatest source of
human-created emissions of phosphorus and nitrogen”. WWF have
estimated that the 115,000 tonnes of Scottish salmon produced in
1999 equated with the phosphorus and nitrogen sewage waste
equivalent of 9.4 million and 3.2 million people respectively
(Scotland’s population is only 5.1 million). Globally, salmon
farms discharge the sewage waste equivalent of tens of millions of
people. In the OSPAR Convention Area alone (including Scotland,
Denmark, Norway and Ireland) nutrient discharges from aquaculture
were estimated in 2000 at 36,000 tonnes of nitrogen and 6,000
tonnes of phosphorus (OSPAR: 2001). In the absence of discharges
of human sewage, agricultural runoff or industrial effluent,
aquaculture’s contribution can be even more significant in
isolated areas of the global economy.
Salmon farm wastes may tip the
ecological balance to such an extent that toxic algal blooms are
triggered (Black: 1993, Berry: 1999, Martin: 2000, Arzul: 2002).
During the past decade, there has been a ‘global epidemic’ in
marine microalgae that are harmful to finfish, shellfish and
humans (Smayda: 1990, Hallengraef: 1993, Cookson: 2001). Mass
mortalities of farmed salmon have been recorded recently in the
Chiloe area of Chile (Carvajal: 2002), Shetland in Scotland
(Cameron: 2001a) and in Norway (Tangen: 2002) where millions have
died in their cages leading to severe financial losses (Cookson:
2001) and huge compensation claims. Mass mortalities are not new
(e.g. Bruno et al: 1989) but their frequency is increasing. The
crux of this simmering debate (Folke et al: 1994, Berry: 1996,
Black et al: 1997, Folke et al: 1997, G3 Consulting: 2000, Berry:
2000, Scottish Executive: 2000) lies in the question of
culpability and, ultimately, insurance liability. For example, are
salmon mortalities always ‘natural’ phenomena or are some
harmful algal blooms self-induced by the excess generation of
toxic salmon farm wastes (Martin: 2000, AQUATOXSAL: 2002)? Instead
of salmon farmers receiving financial compensation for mass
mortalities due to algal blooms (‘the polluter gets paid
principle’ in practice) should not shellfish farmers and
fishermen be paid compensation by salmon farmers responsible for
the spread of toxic algal blooms affecting their rural livelihood?
Harmful algal blooms,
hypernutrification and eutrophication associated with intensive
aquaculture operations have been recorded in Scotland (Jones et
al: 1982, Austin: 1983, Gowen et al: 1983, Gowen et al: 1988,
Stirling and Dey: 1990, Gowen and Ezzi: 1992, Handy and Poxton:
1993, Berry: 1999, Navarro: 2000), Ireland (Gowen: 1990, Massik
and Costello: 1995), Norway (Persson: 1991, Wallin and Hakanson:
1991, Kaartvedt et al: 1991), Japan (Nishimura: 1982, Parsons et
al: 1990), Finland and Sweden (Ruokolahti: 1988, Ronnberg et al:
1992), Hong Kong (Wong and Wu: 1987, Wu: 1994, 1999), New Zealand
(Pridmore and Rutherford: 1992, Rhodes et al: 2001), Tasmania
(Crawford et al: 2001), Canada (Wildish et al: 1993, Smith et al:
2001) and Chile (Arzul et al: 1999). Amnesic, Paralytic and
Diarrhetic Shellfish Poisoning events have plagued the Scottish (Gowen:
1987, Berry: 1997, Gallacher et al: 2000, MacLeod: 2000), Canadian
(Whyte et al: 2000), Irish (Gowen and Bloomfield: 1996, O’Boyle
et al: 2000), Chilean (Clement, A and Lembeye: 1993, Arzul et al:
1999), New Zealand (Mackenzie: 2000) and Norwegian (Dahl: 1989,
Tangen: 2002) coasts. Suffice to say that the evidence pointing to
a causal link, in certain areas, between toxic algal blooms and
salmon farming is surely now beyond reasonable doubt. For example,
a recent study by the Scottish Association of Marine Science
funded by the EC (Navaroo: 2000) found significant planktonic
ecosystem impacts of salmon cage aquaculture in Loch Fyne,
Scotland:
“Results to date reveal higher
concentrations of ammonia, organic phosphorus and nitrogen at the
stations near the fish farm during most months. They also show
higher abundance of bacteria, nanoflagellates and ciliates. This
suggests that fish farm effluents are enhancing local
concentrations of organic and inorganic nutrient. The associated
higher abundances of heterotrophic micro-organisms near the fish
farm suggest that these nutrients may in turn be directly or
indirectly enhancing microbial activity”
The international community have
finally begun to tackle the issue with the International Council
for the Exploration of the Sea (ICES) asking in 1999: “Are the
excreta produced by mariculture (finfish and shellfish farming)
capable of causing significant changes in the growth of coastal
phytoplankton species, particularly of toxin producers?”
AQUATOXSAL, for example, is an EC-funded research project
involving Chile, Argentina, France and Germany investigating the
links between salmon farm wastes and toxic algal blooms (Arzul et
al: 1999, Arzul: 2002, AQUATOXSAL: 2002). As part of AQUATOXSAL,
conferences took place in Puerto Montt, Chile in 1999 and Brest,
France in 2001 with publication of a final report expected later
this year (Arzul, pers.comm). Although the final proceedings are
not yet available the AQUATOXSAL web-site (http://www.aquatoxsal.de)
does provide some details and the AQUATOXSAL forum (http://www.aquatoxsal.de/forum/index.html)
asks if there is “evidence for blooms due to salmonid
aquaculture?” (AQUATOXSAL: 2002). It raises a number of issues:
“We can extrapolate from our data
that the input of inorganic nitrogen coming from all fish farms in
the X. Region in Chile is very high (approx. 17.000 t N). The
influence on the benthos is well documented and we have a clear
relation to aquaculture activities. My question to you: Do we have
evidences (sic) that there is an increase of primary productivity
(phytoplankton, seaweed) in the last years in this region?”
Certainly, in the last year toxic
algal blooms have devastated farmed salmon and shellfish along the
Chilean coast and have even caused human fatalities (Intrafish:
2002c). Another EC project - MERAMED - is investigating
environmental impacts of sea cage fish farming such as sea bass,
sea bream and tuna in the Mediterranean (MERAMED: 2001). In
Scotland, in response to a petition (PE 96) by marine toxicologist
Allan Berry (Berry: 2000), the Scottish Executive have hired
Professor Ted Smayda of the University of Rhode Island to assess
“the impact of nutrient inputs from fish farms on the algal
communities of the Scottish coastal zone”. Another ongoing
five-year project began in 1999 to investigate the impact of sea
lice chemicals including impacts on zooplantkon and phytoplankton
(SAMS: 2002a, 2002c, Edwards: 2002). Previously, the Scottish
Executive published a critique of PE 96 (Scottish Executive: 2000)
and the Scottish Parliament concluded in November 1999 that
“further research into the alleged link between fish farming and
outbreaks of shellfish toxicity take place as a matter of
urgency” (Scottish Parliament: 1999). Dissatisfied with the
response from the Scottish Parliament Mr Berry has now petitioned
the European Parliament asking for an investigation into the link
between toxic algal blooms and salmon farming (Ross: 2001).
In British Columbia the Pollution
and Prevention and Remediation Branch of the Ministry of
Environment hired consultants to “document emerging research
with respect to plankton blooms and netcages” (G3 Consulting:
2000). Particular problem areas in Canada include Broughton
Archipelago (Sutherland et al: 2001) and the Bay of Fundy (Wildish
et al: 1993, Pohle et al: 2000). In the L’Etang Inlet, Bay of
Fundy, “aquaculture operations are the largest anthropogenic
source of nutrient inputs” (Milewski: 2001). In Scotland, an
ongoing project by the Marine Laboratory Aberdeen and the Scottish
Environment Protection Agency (to be completed in August 2002) is
focusing on ten lochs which have been identified as ‘hot
spots’ (Cameron: 2001b, Scottish Executive: 2002). If excess
nutrient enrichment or eutrophication is discovered (Tett and
Edwards: 2002) there is a real risk that curbs will be made on
Scotland’s 350 salmon farms. In Scandinavia, where in addition
to Norwegian salmon farming there is a significant trout farming
industry in Denmark and Finland, HELCOM has recently adopted
stricter “measures aimed at the reduction of discharges from
marine fish farms” (HELCOM: 2001).
In an attempt to deal with the
increasing waste problem, scientific research has focused on the
use of seaweeds to remove salmon farm waste (Chopin et al: 1999,
Troell et al: 1999, Buschmann et al: 2001, Chopin et al: 2001,
Watanbe: 2001), the addition of chemicals or clays to
‘neutralise’ toxic wastes (Rensel: 2000) and the use of
‘nappies’ to collect wastes (SEPA: 1998c). In the final
analysis, completely closed systems for the containment of
contaminated wastes can be the only sustainable solution and that
necessarily rules out open sea cage salmon farming (Cripps: 1994,
Cripps and Kelly: 1996, Costa-Pierce: 1996). If salmon farming is
to have any kind of future, closed sea cage salmon systems may
offer an alternative (G3 Consulting: 2000). Even integrated
systems of seaweed and salmon, for example (Troell et al: 1997),
only deal with a fraction of the waste and such a system will have
difficulties resolving the issue of contamination of PCBs, dioxins
and the suite of toxic chemicals used on salmon farms. The fact
that some of the chemicals used on salmon farms actually kill
seaweeds might be somewhat of a stumbling block (Robertson et al:
1991). The solution to pollution is not dilution.
Food for thought:
Salmon farming is dead in the water
(Miller: 2001b). Nor can the sea cage farming of other marine
species such as tuna, sea bass, cod, halibut, sea bream and
haddock necessarily avoid the same fatal mistakes (Philippine
Daily Inquirer: 2002). The farming of finfish represents a health
hazard (Staniford: 1999, WHO: 1999, Paone: 2000a, Sandison, B:
2001, Bonham-Carter: 2001, Brouwer: 2001, Dowden: 2001, Edwards:
2001b, Grigson and Black: 2001, Healthwell: 2001, Humphrys: 2001,
Lazaroff: 2001, New Straits Times: 2001). Cage aquaculture (Beveridge:
1996) in the sea is one of the major new polluters of the new
millennium. In the Northern hemisphere especially (Allsop et al:
1999, Lundebye et al: 2000), we have polluted our marine
environment to such an extent that we are now reaping the
consequences in the biomagnification of contaminants up through
our food chain (Allsop et al: 2000). The consumption of fish from
areas such as the Baltic (Kiviranta et al: 2002) and by extension
the use of fishmeal and fish oil in salmon farming diets from
contaminated areas (Lundebye et al: 2000) carries with it a public
health warning. Seafood products are a real cause of Government
concern in the UK (MAFF: 1999, Seafish Industry Authority: 2001)
and elsewhere. In particular, the farming of fish high up the food
chain is an extremely efficient way of concentrating contaminants.
In November 2000 the EC’s Scientific Committee on Animal
Nutrition stated that “fish meal and fish oil are the most
heavily contaminated feed materials with products of European fish
stocks more heavily contaminated than those from South Pacific
stock by a factor of ca. eight” (EC: 2000a) whilst the EC’s
Scientific Committee on Food stated that fish can contain ten
times higher levels of dioxins than some other foodstuffs and can
represent up to 63% of the average daily exposure to dioxins (EC:
2000b).
Since ‘you are what you eat’ it
comes as no surprise to discover that farmed salmon contains high
levels of PCBs and dioxins (Mac et al: 1979, Jacobs et al: 2000,
Edwards: 2001b, Wigan: 2001, Easton et al: 2002, FSAI: 2002). Fish
oil is now so contaminated (Jacobs et al: 1997, Jacobs et al:
1998, Lundebye et al: 2000) it should carry a ‘hazardous
goods’ label. Fatty fish such as farmed salmon, which has up to
4-5 times the fat content of wild salmon (Fracassini: 2001, Leake:
2001), presents an even higher risk. That the salmon industry
increased the fish oil (and hence the fat) content of fish feed
from 8% in 1979 to up to 40% in current diets (Davies: 2000,
Jystad: 2001) when knowledge of health risks of contaminated fish
feed existed over 20 years ago (Mac et al: 1979) shows their utter
contempt for consumer protection. Given the level of prior
knowledge apparent within the industry it is therefore difficult
to describe salmon farming’s use of organic contaminants as
“unintentional” (Hellou et al: 2002b). In fact, when the
European Commission gathered data on PCBs and dioxins in fish feed
they found that there was a lack of Government studies but that
“possibly more have been carried out within the industries but
have not been published” (EC: 2002a). How many more
industry-sponsored studies exist in ‘private and confidential’
Government reports (e.g Seafish Industry Authority: 2001)?
Farmed fish feed is so fatty and
contaminated that it even stains the seabed (Henderson et al:
1997, Pirie: 2001, SEPA: 2001a, Hellou et al: 2002a, Hellou et al:
2002b). That the world’s largest salmon feed company, Nutreco,
recently appointed a Corporate Director of Food Safety and are
desperately trying to substitute fish oils with vegetable oils
shows how difficult a task the industry now faces (Hole: 2002,
Sinnott: 2002, Smith: 2002). Nor will it make the task any easier
to hear that rendered animal by-products are judged as a
“necessity in the new millennium” (Tacon: 2000), especially
when the BSE food scare is still fresh in the minds of the public
(Bonham-Carter: 2001, Meikle: 2002). According to Marine Harvest
(a subsidiary of Nutreco) the dioxin issue has “not yet reached
the pinnacle” with ongoing challenges including listeria,
antibiotics, salmonella, PCBs and GM ingredients (Fagan: 2001).
Nutreco (Nutreco: 2001b) also claimed that:
“Nutreco has in place a system for
monitoring dioxins and PCBs in all raw materials used. Since this
scheme came into place during 1999 Nutreco Aquaculture has stayed
beneath proposed EU levels for dioxins. Nutreco Aquaculture fish
feed companies have increased the proportion of fish meal and fish
oil coming from the Pacific sources…Nutreco Aquaculture is
actively eliminating fish meal and fish oil from suspect sources
and the process will be complete in 2001”
With consumers losing trust in
‘suspect’ farmed salmon there are serious question marks over
the safety of Nutreco’s product (Stanley: 2001). Next week’s
Nutreco-sponsored Aquavision conference (Nutreco: 2002) will
search for answers concerning food safety and salmon farming. In
answer to their own question - “if farmed salmon contains
dioxins, is it safe to eat?” (Nutreco: 2001c) - the only safe
answer is surely ‘no’.
Such is the concern that in the UK,
for example, the Food Standards Agency is currently advising
consumers only to eat one portion of oily fish per week (FSA:
2001) and are launching a new testing programme for dioxins in
farmed salmon. In Norway and Finland there are health concerns
over eating too much fish (Horsberg: 1999, ENDS: 2001, Kiviranta
et al: 2002) and over the contamination of fish meal (Lundebye et
al: 2000). The EC are also engaged in a programme to test for PCBs
and dioxins in a range of fish including Chilean, Norwegian,
Canadian and Scottish farmed salmon. Once collated, this
information will ideally allow comparisons to be made between
Northern and Southern hemisphere, freshwater and marine, finfish
and shellfish and between farmed and wild. Consumers, for the
first time, will therefore be able to make an informed decision
about the fish they are buying. Little wonder salmon farming
companies and supermarkets are reluctant to even label their fish
as ‘farmed’ (Fracassini: 2001, Blythman: 2002). Whether they
will ever label artificial colourings (Forristal: 2000), chemicals
used on salmon farms (Fracassini: 2001) or the disease history of
farms (Edwards: 1999) is another matter entirely. Some
supermarkets are pressurising salmon farmers to use less
pesticides (Naysmith: 2001b) but there is a long way to go before
they clean up their act (Cook: 2001, Hendersen and Davies: 2001,
SEPA: 2002, VMD: 2002). Given the ‘hidden extras’, customers
are clearly getting more than they bargained for when opting for
cheap BOGOF (Buy One Get One Free) farmed salmon. In the meantime
consumers are being asked to “Go Wild” and steer clear of
factory farmed fish (Zuckerman: 1999, FoE: 2001a, Morton: 2001,
New Straits Times: 2001, David Suzuki: 2002, Ecotrust: 2002, Grace
Factory Farm Project: 2002, Miller: 2002).
Notes:
[1] A response to the paper by
Naylor et al in Nature (2000) has been submitted to Marine
Pollution Bulletin:
Roth, Eva, Hans Ackefors, Frank
Asche, Christian Balnath, Edward Black, Kenneth Black, Andrew
Boghen, Craig Browdy, Peter Burbridge, John D. Castell, George
Chamberlain, Konrad Dabrowski, Ian Davies, Antoine Dosdat,
Anastasio Eleftheriou, Arne Ervik, Hillel Gordin, Christopher S.
Heinig, Volker Hilge, Ioannis Karakassis, Holmer Kuhlmann, Thomas
Landry, Mathias von Lukowicz, Jaqueline McGlade, Andrew Price,
Robertt B. Rheault, Harald Rosenthal, Ulrich Saint-Paul, Paul A.
Sandifer, Marco Saroglia, William Silvert, Werner Steffens, Doris
Soto, Laszlo Varadi, Johan Verreth, Marc Verdegem, Uwe Waller.
2001? An intellectual injustice to aquaculture development: a
response to the review article on "Effect of aquaculture on
world fish supplies". Marine Pollution Bull. (submitted).
http://silvert.home.sapo.pt/topics.htm#impacts
As yet, the paper remains
unpublished except on the internet:
http://response.home.sapo.pt/index.html
http://response.home.sapo.pt/draft.htm
References: