The greening of PCB analytical methods

Green chemistry incorporates waste minimization, pollution prevention and solvent substitution. The primary focus of green chemistry over the past decade has been within the chemical industry; adoption by routine environmental laboratories has been slow because regulatory standard methods must be followed. A related paradigm, microscale chemistry has gained acceptance in undergraduate teaching laboratories, but has not been broadly applied to routine environmental analytical chemistry. We are developing green and microscale techniques for routine polychlorinated biphenyl (PCB) analyses as an example of the overall potential within the environmental analytical community. Initial work has focused on adaptation of commonly used routine EPA methods for soils and oils. Results of our method development and validation demonstrate that: (1) Solvent substitution can achieve comparable results and eliminate environmentally less-desirable solvents, (2) Microscale extractions can cut the scale of the analysis by at least a factor of ten, (3) We can better match the amount of sample used with the amount needed for the GC determination step, (4) The volume of waste generated can be cut by at least a factor of ten, and (5) Costs are reduced significantly in apparatus, reagent consumption, and labor.