Fish as feed inputs for aquaculture: practices, sustainability and implications

256 Fish as feed inputs for aquaculture – Practices, sustainability and implications

the United Kingdom, the highest level of dioxin reported was only 15 percent of the

level found in Baltic wild salmon.

In order to improve food safety, the EU has adopted a two-fold strategy of

(i) reducing POP inputs into the environment and (ii) restricting the level of POPs that

can enter the human food chain by setting the maximum and action levels^11 of dioxins

in fishmeal, fish oil and aquafeeds over the period 2002–2005 as shown in Table 24.

These levels are close to the levels found in fishmeal and fish oil of European origin

but much higher than the highest levels found in products originating from Chile and

Peru.

The comparisons between different sources of fishmeal and fish oil show very low

levels of dioxin. SCAN commented that “no adverse effects from dioxins would be

expected in mammals, birds and fishes exposed to the current levels of background

pollution” (SCAN, 2000). Despite this, a considerable proportion of the population

of Europe (and undoubtedly other regions) is exceeding the tolerable weekly intake

(TWI) levels for dioxins set by various authorities. As there is a considerable safety

factor imposed on TWI, this does not necessarily mean that there is an appreciable

risk to individual health. However, exceeding TWI levels erodes the protection of this

safety factor.

European exposure to dioxins and PCBs is decreasing (by a factor of about

50 percent over the last 10–15 years) due to improved waste management and

restrictions on the use of these materials.

6.3.2 Transmissible spongiform encephalopathy (TSE)

First, it is important to state that there is no epidemiological evidence for the

transmission to humans of a variant of CJD caused by prions that use fish or fish

products as vectors (GLOBEFISH, 2001).

A temporary EU ban on the use of animal proteins in certain livestock feeds was

approved in 2000 (Commission Decision 2000/766/EC; Council of the European

Union, 2000) over the period to June 2003 and has since been extended to June 2005.

The main purpose of this action by the EU was the removal of meat and bone meal

from European animal feeds, together with the destruction of stocks of this material,

in an effort to contain the spread of BSE. A permanent TSE Regulation (1234/2003)

amending regulation 999/2001 covering feed controls came into effect in September

2003 (although the ban on the use of blood products and blood meal was lifted). The

EU ban is still in force at the time of writing.

The EU ban on the use of animal proteins includes the use of fishmeal in ruminant

feeds but does not ban its use in feeds for pigs or poultry, or its use in aquafeeds. The

EU ban on the use of fishmeal in ruminant feeds was initiated because meat and bone

meal has unfortunately been used at times to adulterate fishmeal in order to alter its

protein content. While the use of fishmeal is not banned in feeds for other animals,

including fish, the ban concerning ruminant feeds causes a further problem for feed

manufacturers generally. This problem is that cross-contamination may occur between

TABLE 24

Current limits on dioxins in fishmeal, fish oils and aquafeeds

Product (ng/kg product)Maximum level (ng/kg product)Action level

Fishmeal 1.25 1.0

Fish oil 6.00 4.5

Compounded fish feed 2.25 1.5

Source: University of New Castle upon Tyne and Poseidon Aquatic Resource Management Ltd. (2004)

(^11) Action levels act as an “early warning”, triggering a proactive approach from competent authorities and
operators to identify sources and pathways of contamination and to take measures to eliminate them.