title: Evaluation and testing of analytical methods for cyanide species in municipal and industrial contaminated waters.
abstract: Total cyanide analysis by distillation is used most commonly to assess cyanide content of water samples. This manual method is robust but slow and provides no information about cyanide speciation, a significant limitation in that cyanide species have substantially different toxicity characteristics. Seven alternative methods for the analysis of cyanide species or groups of species were evaluated in reagent water and five different contaminated water matrices, including five species-specific methods--weak acid dissociable (WAD) cyanide, free cyanide by microdiffusion, available cyanide, automated WAD cyanide by thin film distillation, metal cyanides by ion chromatography--and two automated techniques for total cyanide--total cyanide bythin film distillation and total cyanide by low-power UV digestion. The species-specific cyanide analytical techniques achieved low, ppb-level detection limits and exhibited satisfactory accuracy and precision for most contaminated waters. Analysis of low concentrations of cyanide species in raw wastewater was problematical for the available cyanide and ion chromatography methods, which experienced significant interference problems and/or low recoveries. There was recovery of significant diffusible cyanide in microdiffusion tests with nickel-cyanide-spiked samples, reflecting dissociation of this weak metal-cyanide complex during the test and demonstrating that the test can recover some fraction of WAD cyanide in addition to free cyanide. The automated total cyanide methods, which involve UV digestion, achieved low detection limits for most waters but exhibited low recoveries for some waters.
authors.affiliation: Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Anping
authors.initials: A
authors.lastname: Zheng
authors.forename: David A
authors.initials: DA
authors.lastname: Dzomba
authors.forename: Richard G
authors.initials: RG
authors.lastname: Luthy
authors.forename: Bernard
authors.initials: B
authors.lastname: Sawyer
authors.forename: William
authors.initials: W
authors.lastname: Lazouskas
authors.forename: Prakasam
authors.initials: P
authors.lastname: Tata
authors.forename: Michael F
authors.initials: MF
authors.lastname: Delaney
authors.forename: Larissa
authors.initials: L
authors.lastname: Zilitinkevitch
authors.forename: John R
authors.initials: JR
authors.lastname: Sebroski
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Swartling
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Drop
authors.forename: John M
authors.initials: JM
authors.lastname: Flaherty
mesh_terms: D002852:Chromatography, Ion Exchange; D003486:Cyanides / Q000032:analysis* / Q000737:chemistry*; D004058:Diffusion; D004784:Environmental Monitoring / Q000379:methods*; D007220:Industrial Waste; D014466:Ultraviolet Rays; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D003486:Cyanides; D007220:Industrial Waste; D014873:Water Pollutants