An average citizen in the Federal Republic of Germany, who eats 200 g fish per week,
would take up, at a concentration of 2 mg/kg, 0.4 mg DDT and similar substances per
week or 0.07 mg per day. This is one fourth of the limit set by WHO.
As regards PCB's the World Health Organization concluded (WHO 1976b) that skin
effects may occur in man at a daily intake rate of 4.2 mg per person (of 60 kg) or
0.07 mg/kg of body weight. There are no WHO standards about acceptable daily
intake of PCB's. In general, intake from normal food is in the range of 0.005 to
0.1 mg per person, which gives about a margin of safety from poisonous skin effects
of 1: 100. In the Federal Republic of Germany there is at present no regulation
regarding maximum permissible concentrations of PCB's in fish. In the U.S.A., the
Food and Drug Administration suggested a tolerance level of 5 mg/kg. At this concentration, the average fish eater, consuming 200 g fish per week, would take up
1 mg PCB per week or 0.14 mg per day, much more than with normal food and only
about 1 :30 away from the risk of skin effects.
The question is what actual risk of poisoning by chlorinated hydrocarbons the fish
consumer runs. Fish from locally polluted regions may have concentrations of chlorinated hydrocarbons which make them unfit for human consumption (see Chap. 3.3).
Fortunately concentrations in fish from the main fishery regions are much less.
Before 1970, fish landed in British fishery ports had the following DDT concentrations: cod (Gadus morhua) caught near British coasts up to 0.68 mg/kg in muscle
tissue, herring (Clupea harengus) up to 1.4 rng/kg; cod from open Atlantic regions
far away from the coast had a maximum of only 0.03 mg/kg of DDT (Agricultural
Research Council 1970). From data for fish landed in German fishery ports (Huschenbeth 1973; Huschenbeth 1977), it seems that DDT concentrations have a decreasing
tendency. In 1970-1972 herring from the North Sea had 0.16 mg/kg, in samples
from 1973-1976 concentrations did not surpass 0.07 mg/kg. Cod and coalfish
(Pollachius virens) had only 0.013 mg/kg; the highest concentrations were found
with 0.13 mg/kg in mackerel (Scomber scombrus). Fish from the Baltic Sea had, in
1975, somewhat higher DDT concentrations, 0.4 mg/kg in herring, 0.3 mg/kg in flatfish (Pleuronectidae), below 0.1 mg/kg in cod. In some other areas concentrations
have been higher; for example, sardines from the Black Sea, in 1975, had 1.15 mg/kg
(Huschenbeth 1977). Critical values, compared with the German regulation on maximum permissable concentrations, are only in fish liver. Cod liver from the North Sea
with 0.9-3 rng/kg DDT concentration is legal, but the liver of cod caught in the
Baltic (Gotland and BornhoIm Deeps) contains in general concentrations of above
5 mg/kg, with maximum figures in 1973 of 38 and 77 mg/kg.
What do these concentrations mean for the human consumer of sea fish? It seems
reasonable to conclude that sea fish landed in North Sea fishery ports has an average
DDT concentration of about 0.01 mg/kg. The citizen who eats an average 200 g of
fish per week takes up, with the fish, not more than 0.002 mg DDT per week or
0.0003 mg DDT per day. This is one thousandth of the daily intake accepted by
WHO. Concentrations in fish are only one tenth of concentrations in meat, sausages,
and other food of domestic animal origin (Emiihrnngsbericht 1976).
As regards fish liver and fish oil, there is at present no evaluation available about
average consumption and about the risk to human health by direct intake. One
should, however, keep in mind that fish oil and fish meal are largely used to produce
170
would take up, at a concentration of 2 mg/kg, 0.4 mg DDT and similar substances per
week or 0.07 mg per day. This is one fourth of the limit set by WHO.
As regards PCB's the World Health Organization concluded (WHO 1976b) that skin
effects may occur in man at a daily intake rate of 4.2 mg per person (of 60 kg) or
0.07 mg/kg of body weight. There are no WHO standards about acceptable daily
intake of PCB's. In general, intake from normal food is in the range of 0.005 to
0.1 mg per person, which gives about a margin of safety from poisonous skin effects
of 1: 100. In the Federal Republic of Germany there is at present no regulation
regarding maximum permissible concentrations of PCB's in fish. In the U.S.A., the
Food and Drug Administration suggested a tolerance level of 5 mg/kg. At this concentration, the average fish eater, consuming 200 g fish per week, would take up
1 mg PCB per week or 0.14 mg per day, much more than with normal food and only
about 1 :30 away from the risk of skin effects.
The question is what actual risk of poisoning by chlorinated hydrocarbons the fish
consumer runs. Fish from locally polluted regions may have concentrations of chlorinated hydrocarbons which make them unfit for human consumption (see Chap. 3.3).
Fortunately concentrations in fish from the main fishery regions are much less.
Before 1970, fish landed in British fishery ports had the following DDT concentrations: cod (Gadus morhua) caught near British coasts up to 0.68 mg/kg in muscle
tissue, herring (Clupea harengus) up to 1.4 rng/kg; cod from open Atlantic regions
far away from the coast had a maximum of only 0.03 mg/kg of DDT (Agricultural
Research Council 1970). From data for fish landed in German fishery ports (Huschenbeth 1973; Huschenbeth 1977), it seems that DDT concentrations have a decreasing
tendency. In 1970-1972 herring from the North Sea had 0.16 mg/kg, in samples
from 1973-1976 concentrations did not surpass 0.07 mg/kg. Cod and coalfish
(Pollachius virens) had only 0.013 mg/kg; the highest concentrations were found
with 0.13 mg/kg in mackerel (Scomber scombrus). Fish from the Baltic Sea had, in
1975, somewhat higher DDT concentrations, 0.4 mg/kg in herring, 0.3 mg/kg in flatfish (Pleuronectidae), below 0.1 mg/kg in cod. In some other areas concentrations
have been higher; for example, sardines from the Black Sea, in 1975, had 1.15 mg/kg
(Huschenbeth 1977). Critical values, compared with the German regulation on maximum permissable concentrations, are only in fish liver. Cod liver from the North Sea
with 0.9-3 rng/kg DDT concentration is legal, but the liver of cod caught in the
Baltic (Gotland and BornhoIm Deeps) contains in general concentrations of above
5 mg/kg, with maximum figures in 1973 of 38 and 77 mg/kg.
What do these concentrations mean for the human consumer of sea fish? It seems
reasonable to conclude that sea fish landed in North Sea fishery ports has an average
DDT concentration of about 0.01 mg/kg. The citizen who eats an average 200 g of
fish per week takes up, with the fish, not more than 0.002 mg DDT per week or
0.0003 mg DDT per day. This is one thousandth of the daily intake accepted by
WHO. Concentrations in fish are only one tenth of concentrations in meat, sausages,
and other food of domestic animal origin (Emiihrnngsbericht 1976).
As regards fish liver and fish oil, there is at present no evaluation available about
average consumption and about the risk to human health by direct intake. One
should, however, keep in mind that fish oil and fish meal are largely used to produce
170