Total Cyanide Field Spikes for Industrial Wastewater Samples Verify Successful Sample Integrity, Preservation, Pre‐Treatment and Testing

Abstract

Obtaining accurate and precise results for total cyanide concentrations in wastewater samples is fraught with positive and negative interferences. Even the United States Environmental Protection Agency has acknowledged that it may be difficult or impossible to adequately mitigate all interferences. We demonstrated that a field spike of complex cyanide can be successfully used to demonstrate when sampling, preservation, pre-treatment, and analysis techniques are working adequately to retain any cyanide present in the sample without causing false positives or false negatives. For 257 industrial wastewater effluent samples collected at a wide variety of Greater Boston industries, 237 (92.2%) had usable field spike recoveries, averaging 86.2% recovery. Field spike recoveries for problematic industries that had very high or very low field spike recoveries were useful to show when alternative preservations and field dilutions were successfully preserving total cyanide. The field spike approach is general and should also work in a similar manner for raw and treated drinking water samples.

Assessment of Free and Total Cyanide Levels in the Water Environment of Shatt Al-Arab

“…The highest value of free cyanide concentration in all the stations was recorded in the downstream regions, especially in station W7. This might be due to the increase in population, industrial and agricultural activities [6,11]. Furthermore, this particular place is an important region for river navigation because of the commercial port located nearby.…”

“…Cyanide may also accumulate in body cells by binding with metalloproteins or enzymes such as catalyses or cytochrome c oxidase [8][9][10]. The most important sources of cyanide pollution in the surface water is through mining operations and industrial and agricultural activities [5,[10][11]. Thus this study focuses on the evaluation of free and total cyanide levels and their concentrations and distribution in water in order to know the sources of contaminants in the aquatic system.…”

Free Cyanide Forms During Determination of Free Cyanide in Drinking Water

“…Also, for wastewater, field dilution has been demonstrated to be useful for improved sample preservation by decreasing the impact of the sample matrix, and field spikes are useful for demonstrating sample integrity (Delaney & Blodget 2015).…”