title: Photosynthesis tests as an alternative to growth tests for hazard assessment of toxicant.
abstract: Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of light-saturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures limited by either nitrogen or phosphorus. The sensitivity of the photosynthesis tests were compared to standardized growth tests applied to the same species and toxicants. For Cu and S. costatum the photosynthesis test was up to 300 times more sensitive at light saturation than at light limitation. For the remaining photosynthesis tests no dependence on light condition were found. The photosynthesis tests with Cu and S. costatum were up to 10 times as sensitive as the growth test and most sensitive when the algae were obtained from a phosphate-limited chemostate. For the other photosynthesis tests no dependence on the growth condition were found, and the photosynthesis tests were as sensitive as the growth test. Photosynthesis tests offer an alternative to growth tests for hazard assessment of toxicants.
authors.affiliation: Department of Environmental Science and Engineering, Building 115, Technical University of Denmark, DK-2800 Lyngby, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Petersen
authors.forename: K O
authors.initials: KO
authors.lastname: Kusk
mesh_terms: D017738:Alkanesulfonic Acids / Q000633:toxicity; D003300:Copper / Q000633:toxicity; D056890:Eukaryota / Q000187:drug effects* / Q000254:growth & development; D015386:Hazardous Substances / Q000633:toxicity*; D008027:Light; D010788:Photosynthesis / Q000187:drug effects*; D012680:Sensitivity and Specificity; D018675:Toxicity Tests / Q000592:standards; D014220:Trialkyltin Compounds / Q000633:toxicity
chemical_list: D017738:Alkanesulfonic Acids; D015386:Hazardous Substances; D014220:Trialkyltin Compounds; C030641:alkylbenzyl sulfonic acid; C011559:tributyltin; D003300:Copper