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This study investigates for the first time the presence of microplastics in sediment, water, and benthic organisms (foraminifera) of a marine cave in the Gulf of Orosei (Sardinia, Italy). Microplastics were found in all water, and sediment samples with similar shapes, sizes, and compositions; identified items were mainly fragments and fibers constituted by PVC and polyethylene. Their provenance was supposed to be predominantly from the sea than from the seasonal freshwater supplies from the karst system. Foraminiferal assemblages were mainly constituted by calcareous hyaline taxa in the outer station, while in the inner ones, the agglutinated Eggerelloides advenus was dominant. FTIR analyses on agglutinated shells identified polyethylene. Microplastic items are collected by the foraminifers and sediment grains building the shell chambers. This is the first study providing evidence that marine caves may be collectors of microplastics and that, in these habitats, microplastics enter the biotic matrix at the protist's level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

To understand the fate of plastic in oceans and the interaction with marine organisms, we investigated the incorporation of (bio)polymers and microplastics in selected benthic foraminiferal species by applying FTIR (Fourier Transform Infrared) microscopy. This experimental methodology has been applied to cultured benthic foraminifera Rosalina globularis, and to in situ foraminifera collected in a plastic remain found buried into superficial sediment in the Mediterranean seafloor, Rosalina bradyi, Textularia bocki and Cibicidoides lobatulus. In vitro foraminifera were treated with bis-(2-ethylhexyl) phthalate (DEHP) molecule to explore its internalization in the cytoplasm. Benthic foraminifera are marine microbial eukaryotes, sediment-dwelling, commonly short-lived and with reproductive cycles which play a central role in global biogeochemical cycles of inorganic and organic compounds. Despite the recent advances and investigations into the occurrence, distribution, and abundance of plastics, including microplastics, in marine environments, there remain relevant knowledge gaps, particularly on their effects on the benthic protists. No study, to our knowledge, has documented the molecular scale effect of plastics on foraminifera. Our analyses revealed three possible ways through which plastic-related molecules and plastic debris can enter a biogeochemical cycle and may affect the ecosystems: 1) foraminifera in situ can grow on plastic remains, namely C. lobatulus, R. bradyi and T. bocki, showing signals of oxidative stress and protein aggregation in comparison with R. globularis cultured in negative control; 2) DEHP can be incorporated in the cytoplasm of calcareous foraminifera, as observed in R. globularis; 3) microplastic debris, identified as epoxy resin, can be found in the cytoplasm and the agglutinated shell of T. bocki. We hypothesize that plastic waste and their associated additives may produce modifications related to the biomineralization process in foraminifera. This effect would be added to those induced by ocean acidification with negative consequences on the foraminiferal biogenic carbon (C) storage capacity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This work contributes to the ongoing work aiming at confirming benthic foraminifera as a biological quality element. In this study, benthic foraminifera from intertidal and transitional waters from the English Channel/European Atlantic coast and the Mediterranean Sea were assigned to five ecological groups using the weighted-averaging optimum with respect to TOC of each species. It was however not possible to assign typical salt marsh species due to the presence of labile and refractory organic matter that hampers TOC characterization. Tests of this study species' lists with Foram-AMBI on two independent datasets showed a significant correlation between Foram-AMBI and TOC, confirming the strong relation between foraminifera and TOC. For one of the validation datasets, associated macrofaunal data were available and a significant correlation was found between the foraminiferal Foram-AMBI and the macrofaunal AMBI. The here proposed lists should be further tested with sensitivity-based indices in different European regional settings., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Lead (Pb) is regarded as a highly toxic element that poses a serious threat to biota. A mesocosm experiment was performed to assess the influence of Pb on meiofaunal (metazoans within 45-500 μm) and benthic foraminiferal (protozoan) communities. To this end, sediments bearing such communities were incubated in mesocosms, exposed to different levels of Pb in seawater, and monitored for up to 8 wk. Concentrations of Pb <1 ppm in water did not promote a significant increase of this metal in sediments. Relatively high concentrations of Pb seemed to affect meiofaunal and benthic foraminiferal communities by reducing their richness or diversity, and the abundance of the most sensitive taxa. The mesocosm approach can be considered an effective method to document the responses of meiofaunal and benthic foraminiferal communities to various kinds and concentrations of pollutants over time. This approach allows the evaluation of dose-response relationships, validates the outcomes of field studies, and possibly confirms the sediment quality guidelines and thresholds. Environ Toxicol Chem 2018;37:2439-2447. © 2018 SETAC., (© 2018 SETAC.)

The new record of a shallow-water submarine hydrothermal field (<150 m w.d.) in the western Mediterranean Sea (Tyrrhenian Sea, Italy) allows us to study CO 2 fluid impact on benthic foraminifers. Benthic foraminifers calcification process is sensitive to ocean acidification and to local chemical and physical parameters of seawater and pore water. Thus, foraminifers can record specific environmental conditions related to hydrothermal fluids, but at present their response to such activity is poorly defined. The major outcome of this study is the finding of a very uncommon taxon for the Mediterranean Sea, i.e., the Spiculosiphon oceana, a giant foraminifer agglutinating spicules of sponges. This evidence, along with the strong decrease of calcareous tests in the foraminiferal assemblages associated to hydrothermal activity, provides new insights on the meiofauna living in natural stressed environment. In particular, observations obtained from this study allow us to consider S. oceana a potential tolerant species of high CO 2 concentrations (about 2-4 times higher than the normal marine values) and a proxy of acidic environments as well as of recent ocean acidification processes., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Mercury (Hg) is a highly toxic element for living organisms and is known to bioaccumulate and biomagnify. Here, we analyze the response of benthic foraminifera communities cultured in mesocosm and exposed to different concentrations of Hg. Standard morphological analyses and environmental DNA metabarcoding show evidence that Hg pollution has detrimental effects on benthic foraminifera. The molecular analysis provides a more complete view of foraminiferal communities including the soft-walled single-chambered monothalamiids and small-sized hard-shelled rotaliids and textulariids than the morphological one. Among these taxa that are typically overlooked in morphological studies we found potential bioindicators of Hg pollution. The mesocosm approach proves to be an effective method to study benthic foraminiferal responses to various types and concentrations of pollutants over time. This study further supports foraminiferal metabarcoding as a complementary and/or alternative method to standard biomonitoring program based on the morphological identification of species communities., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Benthic foraminifera and sediment texture were studied on a total of 37 samples, collected from two brackish-water coastal basins: Fogliano Lake and Lungo Lake (central Italy). The research was performed as a preliminary low-cost survey to highlight the degree of the environmental stress and to recognize a possible anthropogenic disturbance. The sedimentological and foraminiferal data were processed by bivariate and multivariate statistical analysis. Three distinct assemblages, referable to different environments were recognized for the Fogliano Lake: inner, intermediate and outer lagoon. Only the outer lagoon assemblage was found in the Lungo Lake. The distribution of foraminifera in the Fogliano Lake suggests a natural environmental stress probably due to the ecological instability typical of marginal environments, while the absence of the inner and intermediate lagoon assemblages in the Lungo Lake suggests an environmental disturbance possibly related to human activities. An interdisciplinary survey including geochemical analyses is recommended in order to deduce the nature and degree of pollution in the Lungo Lake.