title: Screening the toxicity of phosphorous-removal adsorbents using a bioluminescence inhibition test.
abstract: When found in excess, phosphorus (P) has been linked to surface water eutrophication. As a result, adsorbents are now used in P remediation efforts. However, possible secondary toxicological impacts on the use of new materials for P removal from surface water have not been reported. This study evaluated the toxicity of adsorbent materials used in the removal of P from surface water including: fly ash, bottom ash, alum sludge, a proprietary mix of adsorbents, and a proprietary engineered material. Toxicity screening was conducted by performing solid-liquid extractions (SLEs) followed by the bacterial bioluminescence inhibition test with a Microtox® M500. Of the materials tested, the samples extracted at lower pH levels demonstrated higher toxicity. The material exhibiting the most toxic response was the iron and aluminum oxide coated engineered material registering a 66-67% 15-min EC50 level for pH 4 and 5 SLEs, respectively. However, for SLEs prepared at pH 7, toxic effects were not detected for this engineered material. Fly ash and bottom ash demonstrated between 82 and 84% 15-min EC50 level, respectively, for pH 4 SLE conditions. Dried alum sludge and the proprietary mix of adsorbents were classified as having little to no toxicity.
authors.affiliation: Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, Florida, 32816-2450, USA.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Duranceau
authors.affiliation: Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, Florida, 32816-2450, USA.
authors.forename: Paul G
authors.initials: PG
authors.lastname: Biscardi
authors.affiliation: Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, Florida, 32816-2450, USA.
authors.forename: Danielle K
authors.initials: DK
authors.lastname: Barnhill
mesh_terms: D000327:Adsorption; D000534:Alum Compounds / Q000633:toxicity*; D000537:Aluminum Oxide / Q000633:toxicity*; D001419:Bacteria / Q000187:drug effects* / Q000378:metabolism; D060729:Coal Ash / Q000633:toxicity*; D005290:Ferric Compounds / Q000633:toxicity*; D007220:Industrial Waste / Q000009:adverse effects*; D049449:Luminescence; D010758:Phosphorus / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification / Q000379:methods
chemical_list: D000534:Alum Compounds; D060729:Coal Ash; D005290:Ferric Compounds; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; C000499:ferric oxide; D010758:Phosphorus; C041524:aluminum sulfate; D000537:Aluminum Oxide
keywords: adsorption; bioluminescent bacteria; eutrophication; nutrients; water quality