Merging Wildlife and Environmental Monitoring Approaches with Forensic Principles: Application of Unconventional and Non-Invasive Sampling in Eco- Pharmacovigilance

Abstract

Pharmaceutical residues in the environment have the potential to harm wildlife. A population's fragility or an animal's secretive nature may preclude capture and the use of invasive/destructive sampling techniques that are typically used in a risk assessment. Conventionally favoured matrices gathered opportunistically from carcasses have a finite lifespan, thereby limiting the detection window. This multidisciplinary paper aims to promote the use of non-invasive approaches and optimize use of even the most degraded carcasses. We highlight a selection of promising alternative, unconventional and underutilized sample types that could be applied in environmental monitoring efforts and wildlife forensic investigations. With a focus on non-steroidal anti-inflammatory drugs (NSAIDs), now under increasing scrutiny in the freshwater and terrestrial environment, we first illustrate current sampling practices and gaps in knowledge by summarizing exposure of: 1) aquatic organisms to urban effluent discharged into waterways, and, 2) scavenging species to veterinary residues in livestock and other carrion. We then consider the merits and limitations of a range of alternative environmentally robust sample options that offer a broader detection interval for NSAIDs, with emphasis on hair, wool and feathers. The viability of eyes/ocular material, bone matter, fecal matter, injection sites, ingesta/pellets and scavenging/coprophagous insects are also discussed.

Optimised ICP-MS quantification method for using animal faeces as a measure of protected area ecosystem health

“…Biomonitoring is central to ecosystem management, conservation and restoration. Traditional methods of toxicological risk assessment in wildlife however, are often invasive, involving the collection of matrices (blood, hair or tissue) during routine management procedures or samples (kidney, liver, oesophageal tissue) from carcasses following mass mortality events [ [13] , [14] – 15 ]. Further, studies generally focus on a single pollution event or animal species [ [16] , [17] – 18 ], a specific matrix [ 19 , 20 ], multiple environmental matrices [21] or various biological matrices from a particular species [22] .…”

Detection and drivers of exposure and effects of pharmaceuticals in higher vertebrates

“…Exposure pathways for higher vertebrates may be directly through ingestion of and contact with contaminated water, through herbivory of contaminated forage, secondary exposure through predation of contaminated invertebrates and lower vertebrates, and direct exposure through coprophagy. While the potential impact of pharmaceuticals on invertebrates, particularly coprophagous insect communities, has received intense scrutiny [45][46][47], the exposure risks to higher vertebrates within food webs largely remain to be investigated [48]. For aquatic birds and mammals, foraging around STPs is arguably the most important exposure route.…”

“…Exposure studies can be critical in identifying key factors that drive exposure [93][94][95][96], can relate measured residues to levels known to cause adverse effects [97], and measure effects directly using biomarkers [98][99][100][101]. We are not aware of any current long-term wildlife monitoring schemes that target pharmaceutical residue analysis, though pleas have been extended [23,48].…”

“…Such schemes should perhaps focus pharmaceutical monitoring on species that are insectivorous and/or vermivorous in terrestrial systems, piscivorous in freshwater habitats or general scavengers as these three pathways are the likely major exposure routes; this would also be compatible with monitoring for pesticide exposure [74]. Development of techniques to measure trace residues of pharmaceuticals in non-destructive samples, such as feathers, hair, wool and faecal matter [43,48,54,71] can facilitate monitoring without capture of, or disturbance to, animals, and rstb.royalsocietypublishing.org Phil. Trans.…”

“…These techniques may be particularly important when species are secretive and hard to capture, and can be used to gather large numbers of samples at relatively low cost. They are already being used to monitor exposure and, in some cases, effects associated with pesticides and pollutants [84,103] and are likely to be equally useful for monitoring pharmaceuticals [48].…”