Exhibit 16 Deloitte & Touche - ---------- ------------------------------------------------ Deloitte & Touche LLP Telephone: (714) 436-7100 Suite 1200 Facsimile: (714) 436-7200 695 Town Center Drive Costa Mesa, California 92626-1924 December 23, 1998 Securities and Exchange Commission Mail Stop 9-5 450 5th Street, N.W. Washington, D.C. 20549 Ladies and Gentlemen: We have read and agree with the comments in Item 4 of Form 8-K of Spectrum Laboratories, Inc., dated December 17, 1998. Yours truly, /S/ Deloitte & Touche LLP - ------------------------------ Deloitte & Touche LLP