Brazilian wildlife blood links microplastic burdens to human land use
In Brazil, microplastics in tapir and giant anteater blood were associated with human disturbance and proximity to development. A peer-reviewed observational study paired blood measurements with animal tracking across contrasting landscapes. Particles were also detected in remote habitats, while the strongest disturbance within an animal’s home range showed a clearer association than its average exposure.
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Blood and movement data meet in Brazil
Microplastics in the blood of Brazilian tapirs and giant anteaters were associated with the human pressure on their habitats. The peer-reviewed observational study linked blood measurements to tracked movements, finding greater burdens nearer development and waste-management facilities. Particles also appeared in animals inhabiting relatively remote areas, extending the finding beyond wildlife living directly alongside intensive human activity.[1], [2]
Between February 2021 and November 2022, the team sampled 26 lowland tapirs and 21 giant anteaters. Locations included Brazil’s Amazon Arc of Deforestation, an agricultural mosaic in the Cerrado savanna and a cattle ranch in the Pantanal wetland. Of the 47 sampled animals, 40 had sufficient satellite-positioning data for the habitat-use analysis. The blood and movement measurements therefore describe overlapping, but different-sized, groups.[1]
The highest disturbance has the clearer association
A standardized human footprint index represented landscape disturbance. The maximum disturbance inside an animal’s home range was significantly associated with microplastic concentration in blood. Weighted average exposure did not show an equally clear relationship. Proximity to development and waste facilities was also associated with higher burdens. The distinction points to potentially important high-exposure locations within an animal’s wider movements, without attributing its measured burden to a particular location.[1]
Particles vary between animals and reach remote habitats
Confocal Raman spectroscopy identified particles larger than 1 micrometre by their spectral characteristics. Of 17,165 particles analysed, 2,815 were classified as microplastics, and all but four animals carried detectable particles. Polymer composition and abundance varied between individuals. The measurements establish internal exposure in these sampled mammals; clinical disease symptoms and tissue damage were not outcomes measured against those concentrations.[1]
Microplastics were present even in Pantanal animals living many kilometres from development. Air transport, water movement and rainfall provide possible routes for distant dispersal, but the study did not trace individual particles to their origins. Pairing environmental samples with blood measurements could investigate those pathways directly. The observed associations cover two species and a limited set of individuals, rather than establishing an identical exposure pattern for all terrestrial wildlife.[1]
