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Through controlled exposure to tributyltin (TBT), the effects of season, size, and population origin were evaluated on imposex incidence in Stramonita brasiliensis. Four experiments were carried out with organisms collected from three different sites on the Brazilian coast (Torres - Rio Grande do Sul, Farol de Santa Marta - Santa Catarina, and Aracruz - Espírito Santo). S. brasiliensis were anesthetized, sexed, measured, classified by size in small (< 30 mm), medium (≥ 30 to ≤ 40 mm), or big (> 40 mm) and injected in the foot muscle with 0.5 μg g −1 of TBT. Organisms were maintained during one month in aquariums with clear marine water under controlled laboratory conditions. One month after injection, the imposex assessments showed that the population from the southeast (tropical) region was more sensitive to TBT than the population from the south of Brazil (the temperate region). A greater sensitivity in the small and medium categories was observed. Females were also more susceptible to TBT when exposed during their reproductive period. Thus, the present study highlighted the need to ensure that intrinsic biological factors related to organisms are considered in such biomonitoring studies to avoid misinterpretation of results. [ABSTRACT FROM AUTHOR]

The present Letter reports results from a comprehensive theoretical analysis of the inclusion process involving the tetracycline (TC) by β and γ-cyclodextrin (CD). Structure and stabilization energies were calculated, both in gas phase and aqueous solution, using a sequential methodology based on semiempirical and density functional theory (DFT) calculations. By the results, a qualitative structure–property relationship could be established with two main structural features being relevant for inclusion complex stabilization: (i) the depth of inclusion, which favors the hydrophobic contact inside the cavity of CDs and (ii) the hydrogen bonds established between guest and host molecules. [ABSTRACT FROM AUTHOR]

Tributyltin exposure is the primary cause of imposex development in gastropods, making them excellent bioindicators. The present research represents the first examination of butyltin (BT) contamination in surface sediments associated with imposex inLeucozonia nassaandL. ocellatain a harbour complex area in Espírito Santo, southeastern Brazil. The objectives of this study were to evaluate the organotin pollution in the area and to assess the sensitivity of both species to BT pollution through imposex development. Specimens were collected between 2007 and 2010 and the sediments were sampled in 2007. Imposex intensity was evaluated based on the percentage of imposexed females, the relative penis length index (RPLI) and the average value of the vas deferens sequence index (VDSI). BTs were analysed using gas chromatography equipped with a pulsed flame photometric detector (PFPD). The results demonstrated the occurrence of elevated concentrations of BTs in the sediment ranging from 383.7 to 7172.9 ng Sn g−1, indicating a severe contamination of the area, which was confirmed by the biological monitoring results. Our findings also indicated thatL. ocellatais a less sensitive species thanL. nassaand that this differential sensitivity plays a key role in the distributions of the populations of both species in the studied area. [ABSTRACT FROM PUBLISHER]

Phytal communities are characterized by spatial and temporal variation and are influenced by fluctuating biological and physical parameters. This study aimed to describe and compare the gastropods associated with Ulva spp., at three sites of the Espirito Santo coast with ferruginous laterite substrate and different modes of wave exposure. Camburi is characterized by the presence of iron ore particles. Samples were collected bimonthly. At each site, five sampling quadrats were launched at random in the intertidal region. Individuals of Ulva spp. were collected (2964 individuals) and 53 taxa were found. In Camburi the dominant species was Amphitalamus vallei (Barleeidae), while in Capuba and Manguinhos Eulithidium affine (Phasianellidae) predominated. The analyses indicated that Camburi is distinct from the other sites. The lesser wave impacts and the more complex structure of the algae in Camburi, due to the presence of iron ore, may explain this variation. [ABSTRACT FROM AUTHOR]

Imposex is is a well-documented deleterious effect caused by tributyltin (TBT) in females of hundreds of Caenogastropoda species and it is a well-established way of predicting BTs occurrence in marine systems. This study presents the very first information on the presence and distribution of imposex in Stramonita brasiliensis (Claremont and Reid, 2011) in the Brazilian Legal Amazon, within a Ramsar site, during a 6-year appraisal after the TBT global ban in 2008 (2012–2017). Imposex was evidenced in six out of the seven sampling sites, with 39.7% of the total affected females, most of them showing VDSI <1. The temporal appraisal allowed the identification of the introduction of new sources of TBT in some sites, as well as populational recovery in other sampling points. In addition, the dilution effect present in São Marcos Bay was also likely to play an important role in the imposex distribution. [Display omitted] • The first appraisal of imposex in Stramonita brasiliensis from Brazil's Legal Amazon. • Imposex was ubiquitous in most of the sampling sites. • Dilution effect may have influenced imposex distribution. • Levels of imposex represent concerns in the region. [ABSTRACT FROM AUTHOR]

This study evaluates tributyltin (TBT) pollution on a spatial-temporal scale using imposex occurrence in Stramonita brasiliensis in a coastal region of the southeast Brazil, between 2007 and 2018, and tests the viability of this species as a tool to evaluate the environmental quality through the Ecological Quality Ratio (EQR). Imposex indexes varied during the monitoring period, with I% varying from 0% to 100%, Vas Deference Sequence Index (VDSI) from 0 to 4.11 and Index of Relative Penis Length (RPLI) from 0 to 51. The EQR indexes indicated high levels of contamination by TBT in the first years of the study (2007 to 2011), followed by an improvement in the ecological status in the last two years (2017 and 2018). This study confirmed the viability of the use of EQR to evaluate the environmental status in a tropical region by means of an endemic species. Our results indicate that the Espírito Santo coastline is still contaminated with TBT, especially in areas close to ports and fishing activity. • Regions with intense vessel traffic still show high imposex levels in Brazil. • Stramonita brasiliensis is a viable species for the use of Ecological Quality Ratio. • EQR and imposex indexes indicate a decrease in the effects caused by TBT. [ABSTRACT FROM AUTHOR]

Early life exposure to endocrine-disrupting chemicals (EDCs) is an emerging risk factor for development of complications later in life and in subsequent generations. We previously demonstrated that exposure to the EDC organotin (OT), which is present in contaminated seafood, resulted in reproductive abnormalities in female rats. However, few studies have explored the effect of OT accumulation in seafood on pregnancy outcomes. This led us to consider the potential effects of the OT present in seafood on fertility, pregnancy, the placenta, and the offspring. In this investigation, we assessed whether exposure to the OT in contaminated seafood resulted in abnormal fertility and pregnancy features and offspring complications. OT in contaminated seafood (LNI) was administered to female rats, and their fertility, pregnancy outcomes, and fetal liver morphology were assessed. LNI caused abnormal fertility, a reduction in the total number of pups, and an increase in serum testosterone levels compared to controls. Furthermore, LNI exposure caused irregular uterine morphology with inflammation and fibrosis and led to a reduction in embryonic implantation. In pregnant rats, LNI caused abnormal lipid profiles and livers with steatosis features. LNI exposure also causes placental morpho-physiology disruption, a high presence of glycogen and inflammatory cells, and irregular lipid profiles. In addition, LNI exposure caused an increase in large amounts of carbohydrate and lipid delivery to the fetus via an increase in placental nutrient sensor protein expressions (GLUT1, IRβ/mTOR and Akt). In both genders of offspring, LNI exposure led to an increase in body weights, liver megakaryocytes, lipid accumulation, and oxidative stress (OS) levels. Collectively, these data suggest that OT exposure from contaminated seafood in female rats leads to reduced fertility, uterine implantation failure, pregnancy and placental metabolic outcome irregularities, offspring adiposity, liver steatosis, and an increase in OS. Furthermore, some of the effects of OT may be the result of obesogenic and multigenerational effects of OT in adult female rats. Unlabelled Image • Organotin exposure from seafood leads to reduced fertility and uterine implantation. • Organotin exposure from seafood impairs metabolic pregnancy and placental function. • Organotin exposure from seafood impairs fetal liver development and morphology. • Organotin exposure from seafood leads to steatosis features in fetal livers. • Organotin exposure from seafood leads to obesogenic and multigenerational effects. [ABSTRACT FROM AUTHOR]