Title:

Mercury content of tropical sharks

Project Number:

1983-055

Organisation:

Department of Industry Tourism and Trade

Principal Investigator:

Richard Slack-Smith

Project Status:

Completed

FRDC Expenditure:

$0.00

Program(s):

Industry

Objectives

1. Sample up to 1000 sharks of various spp for total mercury content; determine alkyl mercury levels in approximately 150.

2. Examine effects of sex, length, locality on levels. What implications for future of this shark fishery?

3. Sample up to 200 sharks for selenium content

Mercury and selenium content of tropical sharks.

Final Report
ISBN:
ISSN:
Author(s):Dr. J.M. Lyle
Date Published:December 1984

Total mercury, alkyl mercury and selenium concentrations in the muscle tissue of several species of pelagic sharks from northern Australian waters are reported. Mean mercury concentrations ranged between O .13 mg /kg for Carcharhinus brevipinna and 1. 94 mg/kg for C. amblyrhyn choides. Maximum values exceeded 1.5 mg/kg in nine of the species studied and the highest recorded concentration was 3.7 mg/kg for Sphyrna mokarran.

Mercury concentrations were highly dependent on the size of shark, a relationship that was adequately represented by the power function. Males of most of the species studied had significantly higher levels of mercury than females of similar size.