Temporal Changes in Concentrations of Lead and Other Trace Metals in Free-Ranging Eurasian Eagle Owls Bubo bubo in Sweden

Abstract

Patterns of lead and other trace metals were examined in 122 Eurasian eagle owls Bubo bubo found dead in Sweden in the period 1978–2013. Environmental lead (Pb) has decreased over recent decades from reduced anthropogenic emissions but mortality by Pb poisoning is still frequently reported for avian raptors and scavengers exposed to Pb ammunition. One objective here was to determine if Pb concentrations in a nocturnal non-scavenging raptor follow the general decline observed in other biota. Pb concentration in owl liver was significantly correlated with body weight, sex, latitude, longitude and season. Pb showed a significant decreasing trend towards north and west. Starved birds had significantly higher concentrations. Total Pb concentrations in liver averaged 0.179 μg g −1 dry weight (median 0.103) and decreased by 5.6% per year 1978–2013, or 5.3% after adjustment for confounding factors, similar to trends in other species. Among 14 other trace elements only antimony and arsenic showed decreasing trends. Lead isotope ratios 206 Pb/ 207 Pb and 208 Pb/ 207 Pb increased from 1.138 and 2.408 in 1978–1985 to 1.170 and 2.435 in 2010–2013, respectively, demonstrating that the decreasing Pb concentration in eagle owl is related to the phase-out of leaded gasoline in Europe, where Pb additives had much lower isotope ratios than natural lead in Swedish soils. Only one incidence of suspected Pb poisoning (40.7 μg g −1 in liver) was observed indicating that poisoning from ingestion of metallic lead is rare (< 1%) in eagle owl in Sweden, in contrast to what has been reported for eagles.

Lead concentrations in antlers of European roe deer (Capreolus capreolus) from an agricultural area in Northern Germany over a 119-year period—a historical biomonitoring study

“…Our study revealed a marked drop in overall lead concentration in roe deer antlers from the study area following the introduction of unleaded gasoline in the FRG in October 1984. These findings are consistent with the results of other studies that focus on the trend of lead concentrations in antlers of European roe deer over time (Table 2), as well as in antlers of red deer (Cervus elaphus) (e.g., Giżejewska et al 2020) and in other terrestrial biota (e.g., Schnyder et al 2018;Helander et al 2019). This indicates the overall success of the phase-out of leaded gasoline and additional measures taken to reduce lead release to the environment from anthropogenic sources.…”

“…Currently, industry is the main lead emission source, followed by road traffic, the latter now primarily due to tire wear and brake abrasion (McKenzie et al 2009 ; Grigoratos and Martini 2015 ; Adamiec et al 2016 ; Adamiec 2017 ; Bourliva et al 2018 ). Recent studies on lead exposure of biota and humans demonstrate that lead contamination of the environment remains an issue of high concern (Müller-Graf et al 2017 ; Stokke et al 2017 ; Gerofke et al 2018 , 2019 ; Martin et al 2019 ; Pain et al 2019a ; Helander et al 2019 ; Taggart et al 2020 ; Lermen et al 2021 ).…”

Sources of exposure to lead in Arctic and subarctic regions: a scoping review

“…In addition, a lead-zinc mine in Alaska reported 20 times greater concentrations of lead in animal blood and liver samples near mining roads compared to a reference site [ 172 ]. In Sweden, Eurasian eagle owls ( Bubo bubo ) found dead near mines had liver lead isotope ratios similar to an anthropogenic source [ 149 ]. Lead levels in vegetation are also usually elevated near mining sites [ 124–126 , 172 ].…”

“…For example, fish in two remote lakes in northern Saskatchewan had low muscle lead levels (range of means: 0.001–0.044 μg/g ww; Table 4 ), but as there were no industrial operations nearby, the low concentration of lead was probably background levels and/or due to long-range transport [ 153 ]. Lead concentrations in animals can be more accurately identified as background levels if the lead isotope ratios of the animal tissues are similar to the ratios in local aspects of the environment [ 149 , 173 , 174 ].…”

Intoxicação por chumbo: conflitos ambientais na América do Sul e perspectiva sob a conservação de aves silvestres

“…Na América do Sul há normativas sobre a utilização do metal na composição de tintas e combustíveis que buscam diminuir a contaminação ambiental (Plaza, et al, 2018). Em estudo realizado na Europa já foi demonstrado que as concentrações de Pb não tem aumentado em relação ao ambiente, devido a regulamentações que proíbem a presença de metais pesados em combustíveis (Helander, et al, 2019). Entretanto, existem poucos regulamentos que limitam o uso do chumbo em munição em todo mundo, inclusive na América do Sul (Plaza, et al, 2018).…”