GILMARTIN and REVELANTE: CONCENTRATION OF METALS IN TWO ADRIATIC FISH 



the early part of the study period, insufficient 

 material was available to determine levels in 

 certain tissues, but very significant species dif- 

 ferences were noted between fish collected at the 

 same point in time. In most instances mercury 

 was present in greater amounts in specific 

 anchovy tissues and the mean whole fish con- 

 centration was about 50% higher in anchovies. 

 The highest concentrations of mercury were 

 noted in the liver and kidneys. On an annual 

 mean basis the skin and gills of the sardine 

 contained relatively low levels of mercury rela- 

 tive to other body tissues. In contrast, anchovy 

 skin contained higher levels, especially during 

 winter months when concentrations of 190-200 ng 

 g 1 wet weight were observed. The greatest 

 seasonal variation occurred in the digestive tract, 

 where mercury ranged from not detected to 215 

 ngg 1. 



Copper 



Copper levels ranged from 0.6 to 8.5 /jg g^ 

 wet weight (Table 5). As with mercury, anchovy 

 tissues often contained higher concentrations of 

 copper than corresponding sardine tissues, 

 although the differences between the two species 

 were not nearly so pronounced. The highest con- 

 centrations were observed in the liver of both 

 species, with the skin of the anchovy consistently 

 having significantly higher concentrations of 

 copper than that of the sardine. On occasion the 

 digestive tract of the anchovy contained up to 

 5.4x the concentrations in comparable sardine 

 samples. 



Nickel and Silver 



In contrast with mercury and copper, the 

 concentrations of nickel and silver rarely showed 

 significant differences between the two species. 

 Nickel was consistently detected in muscle tissue 

 whereas silver was not, and nickel was occa- 

 sionally observed in anchovy livers but not 

 sardine (Tables 6, 7). Although data indicate 

 higher concentrations in the gills and skin, 

 these may be artifacts introduced by scatter 

 caused by bone matrix in the gills and clays in 

 the skin. The concentrations reported are there- 

 fore considered maximal estimates. 



Table 6.— Concentrations of nickel' (Mg"' wet weight) in 

 tissues of sardine and anchovy from the Adriatic Sea. 



' = maximal estimates due to matrix problem, 

 2ND = not detected. 



Table 5. — Concentrations of copper (/jgg-i wet weight) in 

 tissues of sardine and anchovy from the Adriatic Sea. 



Date 



Skin 



Gills 



Muscle 



Digest. 



Liver 



Total 

 fish 



Table 7. — Concentrations of silver' (yugg"' wet weight) in 

 tissues of sardine and anchovy from the Adriatic Sea. 



Date 



Skin2 



Gills 



Muscle^ 



Digest.' 



Liver^ 



'Suspect value — excluded from mean. 



2ND = not detected. 



Total 

 fish 



197 



