ABSTRACT
The mercury content of certain carnivorous and herbivorous edible fishes in Haifa Bay, Acre Bay and inland fishponds and the water of the bays and streams discharging into them was determined. Of each species, 3–11 specimens (homogenized and assayed separately) were tested for each locality. Total mercury was determined by cold-vapour atomic absorption spectrophotometry, and methyl-mercury by gas-liquid chromatography. Total mercury content of some of the larger specimens of all three carnivorous species from both bays was above 0.5 ppm (the tolerance level). Methyl-mercury accounted for 70–100% of the total mercury content of the fish. All herbivorous specimens contained below 0.1 ppm (and in most cases below 0.03 ppm) total mercury. Total mercury content of the water samples from both bays was 4–8 times higher than, and that of the ponds similar to, that of open-sea water (0.1 ppb). The streams tested contained 0.5–180 ppb total mercury.