DNA contamination of mortuary instruments and work surfaces: a significant problem in forensic practice?

A study of 20 mortuaries was undertaken to assess whether contamination of instruments, tables and cutting areas due to residual material containing human DNA after routine cleaning is an actual or only a theoretical problem. Of the 20 mortuaries studied, 50% were found to have material containing quantifiable human DNA on the instruments and surfaces sampled. This DNA was amplified and found, in some cases, to have been derived from at least three people. Of those that did not yield measurable amounts of DNA, a number of samples were selected at random, amplified and were found to produce partial profiles indicating the presence of low levels of human DNA. The possible sources of human DNA from mortuaries are discussed as well as means to reduce or irradicate the problem of instrument contamination. Finally the implications of these findings for forensic investigations are discussed.