The Canadian Environmental Protection Act, 1999 (CEPA, 1999) requires the Canadian government to categorize all substances on the Domestic Substances List (DSL). Under the Chemicals Management Plan, the Government of Canada addresses chemicals that had not previously undergone rigorous scientific assessment. One such compound, [[4-[[2-(4-cyclohexylphenoxy)ethyl]ethylamino]-2-methylphenyl]methylene]-, propanedinitrile, commonly known as CHPD (cyclohexylphenoxydinitrile), recently underwent a screening assessment and was declared to be “toxic” to the environment. As a result, the Government of Canada ordered the “virtual elimination” of CHPD from the environment. Thus, CHPD may not be present above the lowest concentration that can be accurately measured using sensitive, but routine, analytical methods. We present a solid-phase extraction (SPE) method to determine CHPD in water and wastewater effluent to establish the maximum environmental release limit for this toxic compound. Optimal extraction was attained using an ENVI-18 cartridge. Extracts were analyzed by HPLC–PDA and HPLC–MS/MS techniques; in both matrices, the PDA method had greater sensitivity, less susceptibility to matrix effects, lower limit of quantitation (LOQ) values, and could be successfully validated at multiple spike levels. The lowest concentration of CHPD that could accurately be measured was found to be 108 ng/L in extracts of pure water, using the HPLC–PDA system. Therefore, this value (108 ng/L) will inform regulations on the maximum environmental release limit for CHPD.
