TY - JOUR
T1 - Effects of waterborne cadmium on energy metabolism in the tropical sea cucumber, Stichopus horrens, and a comparison of tissue-specific cadmium accumulation with the temperate sea cucumber Australostichopus mollis
AU - Charan-Dixon, Hannah
AU - Gaw, Sally
AU - Goldstien, Sharyn J.
AU - Glover, Chris N.
N1 - Publisher Copyright:
© 2017 Elsevier Inc.
PY - 2017/7/1
Y1 - 2017/7/1
N2 - The sea cucumber Stichopus horrens is an important component of near-shore ecosystems, and in the Kingdom of Tonga it also comprises an important commercial and subsistence fishery. To assess the sensitivity of this species to the toxic trace metal cadmium (Cd), adult S. horrens were exposed for 96 h to an environmental (15 µg L−1) or effect (765 µg L−1) concentration of waterborne Cd. The respiratory tree and intestine accumulated higher concentrations of Cd than the muscle and body wall, but there were no effects of Cd on tissue ions (sodium, potassium, magnesium, calcium). For comparison, Cd accumulation was also examined in the Australasian sea cucumber Australostichopus mollis. This species displayed a similar pattern of tissue-specific accumulation to S. horrens, but exhibited lower tissue Cd burdens, likely a consequence of lower experimental temperature. Effects on gonad ion content were also seen in this species. At the highest Cd exposure concentration, S. horrens showed impaired ammonia excretion rates and an increased molar oxygen:nitrogen ratio (O:N), indicative of a decreased reliance on protein metabolism. Overall, this study suggests that S. horrens is relatively tolerant of Cd exposure, but raises concerns regarding the subsistence fishery practice of consuming the viscera of this species.
AB - The sea cucumber Stichopus horrens is an important component of near-shore ecosystems, and in the Kingdom of Tonga it also comprises an important commercial and subsistence fishery. To assess the sensitivity of this species to the toxic trace metal cadmium (Cd), adult S. horrens were exposed for 96 h to an environmental (15 µg L−1) or effect (765 µg L−1) concentration of waterborne Cd. The respiratory tree and intestine accumulated higher concentrations of Cd than the muscle and body wall, but there were no effects of Cd on tissue ions (sodium, potassium, magnesium, calcium). For comparison, Cd accumulation was also examined in the Australasian sea cucumber Australostichopus mollis. This species displayed a similar pattern of tissue-specific accumulation to S. horrens, but exhibited lower tissue Cd burdens, likely a consequence of lower experimental temperature. Effects on gonad ion content were also seen in this species. At the highest Cd exposure concentration, S. horrens showed impaired ammonia excretion rates and an increased molar oxygen:nitrogen ratio (O:N), indicative of a decreased reliance on protein metabolism. Overall, this study suggests that S. horrens is relatively tolerant of Cd exposure, but raises concerns regarding the subsistence fishery practice of consuming the viscera of this species.
KW - Bioenergetics
KW - Cadmium
KW - Echinoderm
KW - Nitrogen excretion
KW - Oxygen consumption
KW - Toxicity
UR - http://www.scopus.com/inward/record.url?scp=85014706115&partnerID=8YFLogxK
U2 - 10.1016/j.ecoenv.2017.03.001
DO - 10.1016/j.ecoenv.2017.03.001
M3 - Journal Article
C2 - 28284150
AN - SCOPUS:85014706115
SN - 0147-6513
VL - 141
SP - 1
EP - 8
JO - Ecotoxicology and Environmental Safety
JF - Ecotoxicology and Environmental Safety
ER -