Abstract:

The accumulation and elimination of prometryn in Ruditapes philippinarum was studied by the semistatic
method. Ruditapes philippinarum were exposed to seawaters containing 1.0, 10.0 and 200.0 μg/L prometryn at
(20 ± 1) ℃, respectively. The amount of residual prometryn in Ruditapes philippinarum increased with the increase in
prometryn concentration. The maximum accumulation of prometryn in Ruditapes philippinarum at the three concentrations
was found after exposure for 24, 24 and 6 h with bioconcentration factors of 40.3, 9.54 and 5.35, respectively. As exposure
time increased, prometryn at each concentration could be rapidly accumulated in Ruditapes philippinarum and then
reduced, and after another cycle, finally kept fluctuating slightly around a certain level. The amount of residual prometryn
in Ruditapes philippinarum from all three concentration groups rapidly dropped during the early stage of elimination,
reaching around 10% of the initial level after 24 h, and then fell slowly. The amount of prometryn residue in the 1.0, 10.0 and
200.0 μg/L exposure groups was reduced to below 10.0 μg/kg after 2, 24 and 768 h, respectively. Moreover, the 1.0 μg/L exposure
group reached an undetectable level after 96 h, whereas the two other groups were still detectable after 45 days. This research
suggested that Ruditapes philippinarum can accumulate prometryn rapidly, but its complete elimination will take a long time.

Key words: Ruditapes philippinarum, prometryn, accumulation, elimination