WEF Discussion Forums : Laboratory Management and Technical Issues : Cyanide Method Detection Limit

Thu, 22 Sep 2011 18:18:36 GMT

Is there an approved method that can achieve a 1 ppb (0.001 mg/L) detection of cyanide? We want to meet the Class 3 marine standards, but our contract lab can only get 2 ppb, based on their MDL study.

Fri, 23 Sep 2011 12:45:30 GMT

Actually, 2 ppb is pretty good. (Our MRL is 10 ppb using manual distillation and a Hach spec.) I'd check out the OI Analytical website and get the specs for their automated CN analyzer method, which is EPA approved at 40 CFR 136. You have to register (free) to get any useful info, though.

Chuck Lytle

Mon, 03 Oct 2011 18:17:41 GMT

Thanks for that information.

There is a method. OIA-1677, DW, whch has a low detection limit (0.5 ug/L). We are still researching the availablity of the method, and the applicability to wastewater effluent. Any input?

Thu, 15 Dec 2011 21:06:16 GMT

We use OIA-1677 and OIA-1678. Both are an excellent methods for CN. It is my understanding that OIA-1677 is already accepted if you have sulfite, thiosulfate, or thiocyanate present in the effluent. See footnote 6 in the 40 CFR Parts 122, 136, 141, 143, 430, 455, and 465 [EPA-HQ-OW-2003-0070; FRL-] Rin 2040-AD71. Plus the newest method update rule to be published soon approves more of the cyanide methods from OI-Analytical. I would start by watching the recorded webinar from their website: http://www.oico.com/default.aspx?id=appcntrwbnrbypl&PLID=16.