Can alternative esterification agents (i.e., trimethylsilyldiazomethane (TMSD) or boron trifluoride (BF3)) be used for derivatization in method 8151?
Alternatives to diazomethane or pentafluorobenzyl bromide would be acceptable to use for Method 8151 under the PBMS approach.
There is support for TMSD in the EPA literature for pesticide and herbicide analyses. Please see the following link and the references:
The use of TMSD as a safer alternative to diazomethane seems to be well-documented with regard to reactivity and carcinogenic properties. However, high toxicity warnings are plentiful with all methylating agents. There are also concerns that TMSD (for example) will cause more artifacts as a more efficient methylating agent.
Likewise, BF3 has a good track record with many accredited laboratories using it for derivatization instead of diazomethane or PFBBr.