A noninvasive environmental monitoring tool for brominated flame-retardants (BFRs) assisted by conservation detection dogs

Abstract

Fecal matter is a useful noninvasive/nondestructive media for evaluating contaminants in wildlife, as residues therein have been observed to correlate with body burdens. Conservation detection dog-handler teams can be used to optimize the acquisition of fecal samples. To build on previous work, sentinel-species’ (i.e. mink (Mustela vison) and otter (Lontra canadensis)) fecal matter was opportunistically located by a detection dog team along the tri-river system of Missoula, Montana, USA. Sediments were also collected. Samples were used to develop an analytical method from fecal matter to determine habitat exposure to the brominated flame-retardants (BFRs): polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), 2-ethylhexyl 2, 3, 4, 5-tetrabromobenzoate (EH-TBB), di (2-ethylhexyl)-2, 3, 4, 5-tetrabromophthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). Sediments contained PBDEs (BDE-99 and BDE-209) and EH-TBB at detection rates of 67%, 33% and 67%, respectively. BDE-99, -209 and EH-TBB were also detected in mink and otter feces, at rates of 81%, 25% and 81%, respectively; plus BEH-TEBP at 13%. BFR levels correlated positively with human population density except along the lower Bitterroot River, where BDE-209 sediment and feces levels exceeded other sites by several orders of magnitude. Fecal matter body burden estimates indicated marginal PBDE exposure. However, exposure to their replacements, EH-TBB and BEH-TEBP, were at levels that may adversely affect healthy Mustelidae populations. Proof-of-concept was achieved; validation results were within established standards for the development of analytical methods. The established application of conservation dog-handler teams to facilitate the collection of fecal matter for BFR analysis represents a valuable, but currently underutilized environmental monitoring tool.