22 research outputs found
Bisphenol A migration from plastic materials: direct insight of ecotoxicity in Daphnia magna
Bisphenol A (BPA) is an endocrine disrupting
chemical (EDC) whose migration from food packaging is
recognized worldwide. However, the real overall food
contamination and related consequences are yet largely
unknown. Among humans, children’s exposure to BPA
has been emphasized because of the immaturity of their
biological systems. The main aim of this study was to
assess the reproductive impact of BPA leached from commercially
available plastic containers used or related to
child nutrition, performing ecotoxicological tests using
the biomonitoring species Daphnia magna. Acute and chronic tests, as well as single and multigenerational tests
were done. Migration of BPA from several baby bottles
and other plastic containers evaluated by GC-MS indicated
that a broader range of foodstuff may be contaminated
when packed in plastics. Ecotoxicological test results
performed using defined concentrations of BPA were in
agreement with literature, although a precocious maturity
of daphnids was detected at 3.0 mg/L. Curiously, an
increased reproductive output (neonates per female) was
observed when daphnids were bred in the polycarbonate
(PC) containers (145.1±4.3 % to 264.7±3.8 %), both in
single as in multigenerational tests, in comparison with the
negative control group (100.3±1.6 %). A strong correlated
dose-dependent ecotoxicological effect was observed, providing
evidence that BPA leached from plastic food packaging
materials act as functional estrogen in vivo at very low
concentrations. In contrast, neonate production by daphnids
cultured in polypropylene and non-PC bottles was slightly but
not significantly enhanced (92.5±2.0 % to 118.8±1.8 %).
Multigenerational tests also revealed magnification of the
adverse effects, not only on fecundity but also on mortality,
which represents a worrying trend for organisms that are
chronically exposed to xenoestrogens for many generations.
Two plausible explanations for the observed results could be
given: a non-monotonic dose–response relationship or a mixture
toxicity effect
Factors influencing terrestriality in primates of the Americas and Madagascar
Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (bodymass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use
Factors influencing terrestriality in primates of the Americas and Madagascar
Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use