Heavy metal accumulation in tissue/organs of a sea cucumber, Holothuria leucospilota

摘要

Holothuria leucospilota Brandt, the large black sea cucumber, is a non-selective depositfeeder, and is commonly found in the bottom of shallow waters in Hong Kong, where the sediments are often polluted with eavy metals. This study was designed to test the possibility of heavy metal accumulation by the sea cucumber at two sites in Hon Kong. Atomic absorption spectrophotometer was used to measure Cu and Zn concentrations in various tissue/organs of the animal as well as in the sedments. The resutl indicated that H. leucospilota accumulated zinc in the longitudinal muscle bands (97.27-98.07 ppm in dry weight) and in the respiratory tree (83.92-89.64 ppm in dry weight). Copper concentrations in these two organs were much lwer than that of zinc. After he animals were kept in the aquarium without sediment for 40 days, zinc concentration of the longitudinal muscle and respiratory tree decreased by 48