For more than 50 years perfluoroalkyl substances (PFASs) have found worldwide industrial and household uses. Some PFASs are presumed to be persistent and bioaccumulative. Roe deer (Capreolus capreolus) are thought to be a suitable bioindicator for the accumulation of organic xenobiotics. Due to the ubiquitous nature of PFASs in the environment a retrospective study on temporal trends was carried out. A total of 110 deer liver pools collected from 1989 to 2010 in Germany were analyzed for their levels of PFASs. The highest concentrations were measured for perfluorooctane sulfonate (PFOS) (median 6.3 μg/kg). Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were detected with median concentrations of 0.5 μg/kg, 1.2 μg/kg and 0.3 μg/kg, respectively, while concentrations of the other PFASs were below the limit of quantification. PFOS concentrations decreased significantly (rₛ = −0.741; p = <0.0001) from 9.2 μg/kg in 2000 to 1.8 μg/kg in 2010.

Lead concentrations in hard antlers of adult European roebucks (Capreolus capreolus) were analyzed to assess lead exposure of roe deer roaming the floodplain of the Innerste River, a river system contaminated due to historical metal ore mining, processing, and smelting in its upper reaches. Antler lead concentrations of roebucks culled in the period 1939–2018 within or close to the Innerste floodplain ranged between <0.17 mg Pb/kg (limit of detection) and 51.5 mg Pb/kg (air-dry weight). Median lead concentration in antlers of roebucks culled within the floodplain was 11.1 mg Pb/kg, compared to 2.3 mg Pb/kg in antlers of bucks culled in the floodplain vicinity (P < 0.01). Sampling year had no significant effect on antler lead concentrations (P = 0.748). Lead isotope ratios of antlers from the Innerste downstream area (²⁰⁶Pb/²⁰⁷Pb: 1.179–1.181; ²⁰⁸Pb/²⁰⁶Pb: 2.083–2.085) fell within the range of those reported for hydrothermal vein deposits from the upper catchment area of the Innerste River in the Harz Mountains. Our study demonstrates the long-lasting impact of the historical metal ore mining, processing, and smelting in the Harz Mountains on lead pollution in floodplains of rivers draining this area and the lead exposure of wild herbivores inhabiting the floodplains. Furthermore, it highlights the suitability of roe deer antlers for monitoring environmental lead levels and the usefulness of lead isotope signatures in antlers for source apportionment of lead pollution.

As a result of their ubiquitous presence in the environment perfluoroalkyl acids (PFAAs) have been demonstrated in numerous organisms worldwide, in particular in those of higher trophic levels. The fact that PFAAs have been detected in various human matrices, together with the resultant potential human health risks, knowledge of possible paths of entry and distribution in various ecosystems, is of great importance. In this context pooled samples of terrestrial ecosystems – roe deer liver (n = 141), earthworms (n = 44) as well as leaves from beech and poplar trees (n = 70) – from the year 1989–2015 were obtained from the German Environmental Specimen Bank and examined for the presence of 11 PFAAs for the first time. In addition to determining individual and total PFAA concentrations, temporal trends have been deduced in order to determine the effectiveness of regulatory measures. The highest total mean concentration of PFAAs (sum of the concentrations of the 11 analytes) were 9.9 μg/kg in the roe deer liver samples, followed by earthworm samples with a mean PFAA concentration of 3.5 μg/kg and leaves with a mean total concentration of 2.5 μg/kg. In regard to temporal trends there was a significant reduction of concentrations for perfluorooctane sulfonate, perfluorooctanoic acid, perfluorononanoic acid and perfluorodecanoic acid in roe deer liver from 2003 to 2015, an indication of the effectiveness of regulatory measures. The same is true for the perfluorooctane sulfonate concentrations in earthworms and for perfluorooctanoic acid concentrations in the leaves. In contrast, an increase in perfluorobutanoic acid concentrations was observed from 2003 to 2015 in all three matrices. In summary it must be noted that in spite of the discernible effectiveness of minimization strategies, PFAAs are still detectable in terrestrial matrices and concentrations of other PFAAs as perfluorobutanoic acid appear to be increasing.

Antimicrobial resistance (AMR) is a recognised threat to global health. Obtaining data on the prevalence of AMR in environmental bacteria is key to understanding drivers and routes of transmission. Here, 325 Shiga toxin negative deer faecal samples—gathered from across the Scottish mainland—were screened for the presence of AMR Escherichia coli and investigated for potential risk factors associated with AMR occurrence. E. coli with resistance to antimicrobials of clinical health concern, including carbapenems and 3rd generation cephalosporins, were targeted. Ninety-nine percent of samples yielded E. coli, and the prevalence of resistant E. coli at the level of faecal samples was 21.8% (n = 71) for tetracycline, 6.5% (n = 21) for cefpodoxime, 0.3% for ciprofloxacin (n = 1), with no recorded resistance to meropenem. Potential risk factors for tetracycline and cefpodoxime resistance were investigated. The presence of broadleaved woodlands was significantly associated with both AMR phenotypes, which may relate to land use within or around such woodlands. Associated risk factors varied across resistance phenotype and deer species, with proximity or density of horses an indicator of significantly decreased and increased risk, respectively, or tetracycline and cefpodoxime resistance in E. coli from roe deer, but not from red deer. Distance from wastewater treatment plants was a significant risk factor for tetracycline resistance in E. coli from red deer but not from roe deer. Data indicated that AMR E. coli can occur in wild deer populations that are not directly exposed to the selective pressure exerted by antimicrobial treatment. Overall, resistance to critically important antimicrobials was found to be low in the studied population, suggesting no immediate cause for concern regarding human health. Utilising existing culling frameworks, wild deer in Scotland could function well as a sentinel species for the surveillance of AMR in the Scottish environment.

Roe deer (Capreolus capreolus) antlers are a useful tool for historical biomonitoring because they accumulate potential bone-seeking pollutants (Pb) and are naturally standardized environmental samples. Lead concentrations were measured in 45 antlers of roe deer, shot in the period 1925-2003 in the Upper Meža Valley, Slovenia, where lead production started at the end of the nineteenth century. Extremely high levels of lead were determined in the antlers (mean (SD) 54.7 (33.5) mg/kg, dry weight; range 2.69-554 mg/kg), exceeding previously reported levels of Pb in roe deer antlers from Europe. After the cessation of primary lead production in 1989, lead levels in antlers have been declining but are still high (period 2000-2003: mean (SD) 5.81 (6.60) mg/kg; range 2.69-7.74 mg/kg) compared with other areas of Slovenia. Spatial comparison confirmed that the lead contamination declines with distance from the emission source. The study confirmed the exceptional potential of roe deer antlers as a bioindicator of lead contamination of the environment.

The aim of the study was to investigate the effects of age and sex on the content of heavy metals (Pb, Cd, Zn and Cu) in the hair, liver and the longissimus lumborum muscle of roe deer (Capreolus capreolus L.). In addition, correlations between heavy metals in individual tested matrices were studied as well as an attempt was made to explain the reasons for their accumulation in specific research matrices. The levels of Zn and Cu were measured using atomic absorption spectroscopy (F-AAS). The levels of Pb and Cd were analysed by means of electrothermal atomic absorption spectroscopy (ET-AAS). In the own research, sex-related statistically significant differences in concentrations of analysed elements were confirmed. Higher levels of the elements were observed in samples collected from does (except for Cd in the liver samples of 6–7-month-old male fawns) but only in some cases, these values were statistically significantly higher. In some cases, age-related differences in the content of individual metals were also confirmed. Age-dependent increased Pb levels in the muscle and liver were reported in 6–7-month-old, <3–4-year-old, <5–6-year-old males. Similar relationships were confirmed for Zn in the bucks’ muscles. In the group of does, the increase in heavy metal concentrations with aging was observed for Zn in the muscle and for Pb in the liver. In the other cases, the trend of age-related level changes regarding heavy metals was not clearly demonstrated. Significant positive correlations between Cu and Cd were found for all samples, and significant negative correlations of Cu with Pb were found for the hair and liver. There was a negative correlation of Zn with Cu in all matrices. The study also revealed a negative correlation between Zn and Pb in muscle and a strong significant negative correlation between Zn and Cd in hair and in the liver.

We analyzed the lead content in antlers of 90 adult European roe bucks (Capreolus capreolus) that had been culled between 1901 and 2019 in an agricultural-dominated hunting district in Lower Saxony (Northern Germany). Antler lead values ranged between 0.2 and 10.9 mg/kg dry weight. Median lead concentration was highest after World War II, during a period (1956–1984) of rapidly increasing mass motorization and use of leaded gasoline. Lead levels in antlers decreased markedly after the phase-out of leaded gasoline, but high values were still found in some recently collected antlers. This could indicate persistent lead pollution from former use of lead additives to gasoline, other traffic-related sources, or from agricultural sources (e.g., sewage sludge, fertilizers). This study highlights the suitability of analyzing roe deer antlers for the historical monitoring of changing lead levels in the environment. By collecting antlers and providing them for study, local hunters can significantly contribute to environmental surveillance and the monitoring of environmental pollution by bone-seeking contaminants.

The European roe deer (Capreolus capreolus) is one of the most abundant ungulate species in Europe. Many studies have investigated its distribution, behavior, and ecology, but few have focused on its role as bioindicators for pollutants, particularly regarding antlers, which has been shown to indicate also deer physiology. The presence of geothermal power plants can induce accumulation of potentially polluting elements (such as Tl, S, and Pb). Thus, we collected roe deer samples from areas of Tuscany (Italy) where power plants are present. They were divided according to whether their home range included areas close or far from geothermal power plants. We analyzed the body measurements and the profile of the minerals in the liver and antlers tissues using the ICP-OES technique. Results showed that livers from roe deer close to power plant accumulated higher quantity of Bi, Co, Ni, Tl, and S compared to controls. Males culled close to geothermal power plants had significantly lower values for weight and chest circumference, and also, the antlers showed higher values for Li and Sr in the first sampling position. Thus, despite the small sample size in this preliminary study, antlers and livers of roe deer seem to be a bioindicator of industrial impact on the environment.

The study was performed on 20 (10 males, 10 females) roe deer (Capreolus capreolus) to investigate the concentration of cadmium, lead, mercury, and arsenic in the muscle tissue. They reside in forest and meadow, about 50 km distance from industrial activities and traffic. Samples were taken from the musculus biceps femoris of each deer without external contamination after shooting during the regular hunting season on a hunting area close to Eger in Hungary. The determination of heavy metal contents was carried out by inductively coupled plasma optical emission spectrometry (ICP-OES). The statistical analysis was performed by statistical package for the social sciences (SPSS) version 11.0. The measured residue concentration of cadmium was below the limit of detection in the roe deer meat indicating no health risk for the consumers. The average lead concentration (0.48 ± 0.21 mg/kg wet weight) exceeded the regulated maximum limit, but its calculated weekly intake was below the provisional tolerable weekly intake (PTWI). The residue level of mercury is not regulated and the average mercury content of roe deer meat (0.87 ± 0.40 mg/kg wet weight) was about half of PTWI, but the consumption of meat with the highest detected concentrations results in higher PTWI than recommended. The measured concentration of arsenic (0.27 ± 0.20 mg/kg wet weight) in the roe deer meat may not pose any health risk for the human consumers according to the PTWI set by the World Health Organization.

The muscle, liver, kidney and fat samples of 20 roe deer of both sexes originating from a hunting area in central Hungary were investigated for the presence of heavy metals such as As, Cd, Hg and Pb, and their contents were evaluated for possible health risk to consumers. Both As and Hg were found at a level below the limit of detection (< 0.5 mg/kg wet weight) in all samples. The median of the measured Cd concentrations was significantly higher in both the kidney and the liver (p = 0.0011) of bucks than of does. In bucks, Cd levels exceeded the respective maximum limits laid down in the European legislation in four kidney and three muscle samples, whereas in does, the measured concentrations were below the respective limits in all samples. The detected amounts of Pb exceeded the maximum limits in the kidney of one buck and eight does, in the liver of two bucks and six does, in the muscle of six bucks and nine does, whereas in all fat tissues of both bucks and does. The concentration of Pb (p = 0.02) was significantly greater in the kidney of does compared to roebucks. Based on data obtained from the present study, the consumption of organs and tissues of the investigated roe deer could be objectionable from food-toxicological point of view and may pose risk to the high consumers of wild game due to their cadmium and lead contents.