ScienceAsia 29 (2003): 209-219 |doi: 10.2306/scienceasia1513-1874.2003.29.209

Toxicity of Mercury to Growth and Survival of Seabass Larvae, Lates calcarifer and the Modifying Effects of Salinity

Waewtaa Thongra-ar^a,*, Preeda Parkpian^b and Armando Tang^c

ABSTRACT: Short-term chronic toxicity tests were conducted to investigate the adverse effects of mercury (Hg) on growth (measured as dry weight) and survival of seabass larvae, Lates calcarifer, and the modifying effects of salinity. Seven-day static-renewal tests were conducted at four salinities: 2, 10, 20 and 30 psu. The experiments were repeated three times for each salinity. Results indicated that seabass larvae were very sensitive to low concentrations of Hg. Based on the actual measured Hg concentrations, the mean NOEC, LOEC and LC₅₀ values for survival were 30.8, 52.5 and 46.2 g L^-1, respectively, while the mean NOEC, LOEC, IC₂₅ and IC₅₀ values for growth were 5.2, 12.6, 8.5 and 19.2 g L^-1, respectively. Salinity did not have any significant effects on the toxicity of Hg on survival and growth of seabass larvae. One possible explanation is that Hg preferentially forms very strong complexes with sulfhydryl groups (-SH) in proteins rather than with chloride.

Download PDF

a Institute of Marine Science, Burapha University, Bangsaen, Chon Buri 20131 Thailand.
b School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathum Thani 12120 Thailand.
c EVS Environment Consultants, 195 Pemberton Avenue, North Vancouver, B.C. V7P 2R4 Canada.

* Corresponding author, Email: waewtaa@bucc4.buu.ac.th

Received 31 Oct 2002, Accepted 4 Apr 2003