title: Methodological basis for the optimization of a marine sea-urchin embryo test (SET) for the ecological assessment of coastal water quality.
abstract: The sea-urchin embryo test (SET) has been frequently used as a rapid, sensitive, and cost-effective biological tool for marine monitoring worldwide, but the selection of a sensitive, objective, and automatically readable endpoint, a stricter quality control to guarantee optimum handling and biological material, and the identification of confounding factors that interfere with the response have hampered its widespread routine use. Size increase in a minimum of n=30 individuals per replicate, either normal larvae or earlier developmental stages, was preferred to observer-dependent, discontinuous responses as test endpoint. Control size increase after 48 h incubation at 20 degrees C must meet an acceptability criterion of 218 microm. In order to avoid false positives minimums of 32 per thousand salinity, 7 pH and 2mg/L oxygen, and a maximum of 40 microg/L NH(3) (NOEC) are required in the incubation media. For in situ testing size increase rates must be corrected on a degree-day basis using 12 degrees C as the developmental threshold.
authors.affiliation: Laboratorio de Ecoloxía Mariña, Facultade de Ciencias do Mar, Universidade de Vigo, E-36200 Galicia, Spain.
authors.forename: Liliana
authors.initials: L
authors.lastname: Saco-Alvarez
authors.forename: Iria
authors.initials: I
authors.lastname: Durán
authors.forename: J
authors.initials: J
authors.lastname: Ignacio Lorenzo
authors.forename: Ricardo
authors.initials: R
authors.lastname: Beiras
mesh_terms: D000818:Animals; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D019015:Geologic Sediments / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010063:Ovum / Q000187:drug effects* / Q000254:growth & development; D047328:Paracentrotus / Q000187:drug effects* / Q000196:embryology; D054712:Salinity; D012623:Seawater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical