Portable X-ray Fluorescence for Measuring Lead in the Hair of Wild Mammals

Abstract

Lead exposure threatens scavenging wildlife globally. For inexpensive estimation of lead concentration in bones from avian scavengers, portable X-ray fluorescence (XRF) devices have been trialed. However, portable XRF has not been validated for tissue lead measurement in non-human mammalian scavengers. We evaluated portable XRF for hair lead measurement in the endangered Tasmanian devil (Sarcophilus harrisii). We first analyzed large ([~]1.0 g) hair samples from 39 deceased animals from southeastern Tasmania via portable XRF and then inductively-coupled plasma mass spectrometry (ICP-MS) (validation study). We then measured lead concentrations via portable XRF only in 61 small ([~]0.1 g) hair samples from live devils from a plantation landscape (plantation study). Portable XRF measures of hair lead levels were positively correlated with ICP-MS values (R2 = 0.61). In the validation study, 95% of sampled Tasmanian devils had relatively low lead levels ( 15 mg/kg). Mean lead levels in the plantation study and validation study were not significantly different. Our preliminary results suggest that portable XRF can provide a useful measure of differences in lead levels in wildife hair over a coarse scale. We provide recommendations for further research and refinement of this method. SynopsisPortable XRF can provide inexpensive and non-destructive analysis of environmental contaminants in wildlife. We present the first evaluation of portable XRF for analysis of lead contamination in mammalian scavenger hair.