Relation between D H ratios and ¹⁸O ¹⁶O ratios in cellulose from linen and maize-Implications for paleoclimatology and for sindonology

The ¹⁸O ¹⁶O ratios of cellulose and the D H ratios of cellulose nitrate were determined for linen, a textile produced from the fibers of the flax plant Linum usitatissimum, and for maize (Zea mays) from a variety of geographic locations in Europe, the Middle East, and North and South America. The regression lines of δD values on δ¹⁸O values had slopes of 5.4 and 5.8 for the two species. Statistical analysis of results reported in the only other study in which samples of a single species (the silver fir Abies pindrow) that grew under a variety of climatic conditions were analyzed yielded slopes of ~6 when δD values of cellulose nitrate were regressed on δ¹⁸O values of cellulose. The occurrence of this previously unrecognized relationship in three species suggests it may obtain in other plants as well. Determining the basis for this relationship, which is not possible given current understanding of fractionation of the isotopes of oxygen and hydrogen by plants, should lead to increased understanding of how D H and ¹⁸O ¹⁶O ratios in cellulose isolated from fossil plants are related to paleoclimates. The separation of most linen samples from Europe from those originating in the Middle East when δD values are plotted against δ¹⁸O values suggests it may be possible to use the isotope ratios of cellulose prepared from the Shroud of Turin to resolve the controversy concerning its geographic origin.