A test of the citrate method of PMI estimation from skeletal remains

- The method of citrate content for PMI estimation is tested using pig ribs.
- Citrate content in bone was found to decrease with increased PMI.
- Terrestrial and aquatic environments did not differ significantly in citrate loss.
- The method is relatively simple and inexpensive to apply.
- Additional study of this method is needed.

Citrate content in bone has been shown to be associated with the postmortem interval (PMI), with citrate decreasing after death as a function of time. Here we test this method using porcine ribs for the period of 1-165 days after death, and also assess citrate content and variation from samples placed into two different postmortem environments (terrestrial and aquatic). Higher citrate variation, lower citrate recovery, and a weaker association with time were found in this study as compared to others. Citrate content, however, was found to decrease with increasing PMI, and the method was found to be easy and inexpensive to apply. No significant differences were found in citrate loss between terrestrial and aquatic environments. Although more research is needed, citrate content appears to be a promising new approach in estimating PMI from skeletal remains.