High Levels of Heavy Metal(loid)s Related to Biliary Hyperplasia in Hedgehogs (Erinaceus europaeus)

Abstract

Heavy metal(loid) pollution of ecosystems is a current One Health problem. The liver is one of the most affected organs in cases of acute or chronic exposure to abnormal amounts of these substances, inducing histopathologic lesions. In order to assess the influence of heavy metal(loids), forty-five European hedgehogs (Erinaceus europaeus) were submitted to necropsy, and liver samples were collected for a routine histopathology exam and metal(loid)s determination (As, Cd, Co, Cr, Cu and Pb) by ICP-MS. Age was estimated during the necropsy exam. Biliary hyperplasia was the most frequent lesion observed (16/45; 35.56%). No statistically significant associations were found between biliary hyperplasia and age or sex. Metal(loid)s’ concentrations were higher in animals with biliary hyperplasia (except for As). There was a statistically significant difference for both Cd and Co. For As, Cd and Co, cubs and juveniles animals showed significantly lower concentrations than elder individuals. Only for Pb were significant differences found between females and males. As described in the literature, exposure to metal(loid)s may be a cause of biliary hyperplasia, although further research (including the use of biochemical methods) is needed to support these results. To the authors’ knowledge, this is the first report of this association in hedgehogs.

A Review of the Occurrence of Metals and Xenobiotics in European Hedgehogs (Erinaceus europaeus)

“…Including information on the age of the individuals in their study, Rautio et al (2010) [57] found significant increases in the levels of several metals (Cd, Mo, Cu, Fe, Mn) with increasing age, although this depended on the tissue types analysed, suggesting an age-related bioaccumulation of metals in hedgehogs. This was supported by Jota Baptista et al (2023) [63], showing that concentrations of Cd and Co were significantly lower in juvenile compared to adult individuals. At present, it appears that no values describing physiologically normal concentrations of essential metals exist for European hedgehogs, which complicates an interpretation and discussion of the concentrations of essential metals in hedgehogs.…”

“…In our literature search, we found six studies that investigated the presence of metals in hedgehogs, using sample material ranging from hair; spines; and tissues such as kidney, liver, fat, and muscle to blood [29,[56][57][58][59]63]. The metals tested were silver (Ag), aluminium (Al), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), and zinc (Zn) (see Supplementary Materials for an overview).…”

“…At present, it appears that no values describing physiologically normal concentrations of essential metals exist for European hedgehogs, which complicates an interpretation and discussion of the concentrations of essential metals in hedgehogs. How-ever, Jota Baptista et al (2023) [63] detected biliary hyperplasia in 16 of the 45 hedgehogs examined, concluded that concentrations of metals were higher in individuals with this condition, and suggested that heavy metals and metalloids may be the primary contributing factor causing biliary hyperplasia in hedgehogs.…”

Prickly Connections: Sociodemographic Factors Shaping Attitudes, Perception and Biological Knowledge about the European Hedgehog

“…Several factors contribute to these observations: exposure to pesticides and rodenticides in agricultural areas [26]; traffic collisions and mortality affecting dispersion and population dynamics [27]; and the decreased risk of predation in villages [28]. Regarding synanthropic behaviour, compelling studies demonstrate that hedgehogs are ecosystem sentinels for heavy metal(loid) pollution [29] and human health threats associated with zoonotic diseases [30,31]. Both hedgehogs' ecology and synanthropic behaviour make this mammal a keystone species for agroecosystems and a sentinel for ecosystems and human health (One Health framework).…”

First report of intestinal intussusception in Western European hedgehogs (Erinaceus europaeus)

“…As hedgehogs are one of the mostly common animals in rescue centres, these facilities may provide important opportunities to increase knowledge of this species 2,3 . Some of the most frequently reported reasons for admission in rescue centres include orphans, traumatic lesions due to car collisions and predation, poor nutrition secondary to hibernation disturbances or if births occur too late in the breeding season and parasites 5–8 . The body condition at the beginning of hibernation, the time of the year and the development of the litter (pre‐weaned vs. post‐weaned) have a strong influence in the recovery and mortality of hedgehogs, especially the hoglets and young adults 3 .…”