Antimicrobial resistance (AMR) is a serious problem for public and animal health, and also for the environment. Monitoring and reporting the occurrence of AMR determinants and bacteria with the potential to disseminate is a priority for health surveillance programs around the world and critical to the One Health concept. Wildlife is a reservoir of AMR, and human activities can strongly influence their resistome.The main goal of this work was to study the resistome of wild boar faecal microbiome, one of the most important game species in Europe using metagenomic and culturing approaches. The most abundant genes identified by the high-throughput qPCR array encode mobile genetic elements, including integrons, which can promote the dissemination of AMR determinants. A diverse set of genes (n = 62) conferring resistance to several classes of antibiotics (ARGs), some of them included in the WHO list of critically important antimicrobials were also detected. The most abundant ARGs confer resistance to tetracyclines and aminoglycosides. The phenotypic resistance of E. coli and Enterococcus spp. were also investigated, and together supported the metagenomic results.As the wild boar is an omnivorous animal, it can be a disseminator of AMR bacteria and ARGs to livestock, humans, and the environment. This study supports that wild boar can be a key sentinel species in ecosystems surveillance and should be included in National Action Plans to fight AMR, adopting a One Health approach.

Aquaculture can affect the polyunsaturated fatty acids (PUFA) and mercury (Hg) in fish by altering their diet. Here, planktivorous (silver carp and bighead carp), omnivorous and carnivorous fish with different dietary strategies were selected from two reservoirs, one with on-going aquaculture (WJD) and another without aquaculture (HF) in Southwest China. We compared the total mercury (THg), methylmercury (MeHg) contents and PUFA profiles of fish and their potential diets in these two reservoirs. THg and MeHg contents in omnivorous and carnivorous fish were lower from the WJD Reservoir, which is related to the lower THg and MeHg contents in the artificial fish food. THg and MeHg contents in silver carp from the WJD Reservoir were lower than those from the HF Reservoir, while they were similar in bighead carps from the two reservoirs. The Hg variation in planktivorous fish were inconsistent with that in plankton. THg contents in phyto- and zooplankton from the HF Reservoir were higher than those from the WJD Reservoir, yet their MeHg contents were similar. Artificial fish food which contained higher total PUFA eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), significantly increased the total PUFA and EPA + DHA contents in carnivorous fish, but had less effect on that in omnivorous fish from the WJD Reservoir. Eutrophication caused by aquaculture reduced total PUFA and EPA + DHA contents of plankton in WJD, yet did not reduce those in planktivorous fish. The impacts of aquaculture on Hg and PUFA accumulated in fish were varied among different fish species, and the mechanism needs further exploration.

Crude oil and its constituents can have adverse effects on ecological and human health when released into the environment. The Canadian Council of Ministers of the Environment (CCME) has developed remedial guidelines and a risk assessment framework for both ecological and human exposure to PHC. One of the assumptions used in the derivation of these guidelines is that plants are unable to take up PHC from contaminated soil and therefore subsequent exposure at higher trophic levels is not a concern. However, various studies suggest that plants are indeed able to take up PHC into their tissues. Consumption of plants is a potential exposure pathway in both ecological (e.g., herbivorous and omnivorous birds, and mammals) and human health risk assessments. If plants can uptake PHC, then the current approach for risk assessment of PHC may underestimate exposures to ecological and human receptors. The present review aims to assess whether or not plants are capable of PHC uptake and accumulation. Twenty-one articles were deemed relevant to the study objective and form the basis of this review. Of the 21 primary research articles, 19 reported detectable PHC and/or its constituents in plant tissues. All but five of the 21 articles were published after the publication of the CCME Canada-Wide Standards. Overall, the present literature review provides some evidence of uptake of PHC and its constituents into plant tissues. Various plant species, including some edible plants, were shown to take up PHC from contaminated soil and aqueous media in both laboratory and field studies. Based on the findings of this review, it is recommended that the soil-plant-wildlife/human pathway should be considered in risk assessments to avoid underestimating exposure and subsequent toxicological risks to humans and wildlife.

Short chain chlorinated paraffins (SCCPs) are under review for inclusion into the Stockholm Convention on Persistent Organic Pollutants. However, limited information is available on their bioaccumulation and biomagnification in ecosystems, which is hindering evaluation of their ecological and health risks. In the present study, wild aquatic organisms (fish and invertebrates), water, and sediment collected from an enclosed freshwater pond contaminated by electronic waste (e-waste) were analyzed to investigate the bioaccumulation, distribution, and trophic transfer of SCCPs in the aquatic ecosystem. SCCPs were detected in all of the investigated aquatic species at concentrations of 1700–95,000 ng/g lipid weight. The calculated bioaccumulation factors (BAFs) varied from 2.46 to 3.49. The relationship between log BAF and the octanol/water partition coefficient (log KOW) for benthopelagic omnivorous fish species followed the empirical model of bioconcentration, indicating that bioconcentration plays an important role in accumulation of SCCPs. In contrast, the relationship for the benthic carnivorous fish and invertebrates was not consistent with the empirical model of bioconcentration, implying that the bioaccumulation of SCCPs in these species could be more influenced by other complex factors (e.g., habitat and feeding habit). Preferential distribution in the liver rather than in other tissues (e.g., muscle, gills, skin, and kidneys) was noted for the SCCP congeners with higher log KOW, and bioaccumulation pathway (i.e. water or sediment) can affect the tissue distribution of SCCP congeners. SCCPs underwent trophic dilution in the aquatic food web, and the trophic magnification factor (TMF) values of SCCP congener groups significantly correlated with their corresponding log KOW values (p < 0.0001). The present study results improved our understanding on the environmental behavior and fate of SCCPs in aquatic ecosystem.

Habitat loss and fragmentation together represent the most significant threat to the world's biodiversity. In order to guarantee the survival of this diversity, the monitoring of bioindicators can provide important insights into the health of a natural environment. In this context, we used the comet assay and micronucleus test to evaluate the genotoxic susceptibility of 126 bats of eight species captured in soybean and sugarcane plantation areas, together with a control area (conservation unit) in the Cerrado savanna of central Brazil. No significant differences were found between the specimens captured in the sugarcane and control areas in the frequency of micronuclei and DNA damage (comet assay). However, the omnivore Phyllostomus hastatus had a higher frequency of nuclear abnormalities than the frugivore Carollia perspicillata in the sugarcane area. Insectivorous and frugivorous bats presented a higher frequency of genotoxic damage than the nectarivores in the soybean area. In general, DNA damage and micronuclei were significantly more frequent in agricultural environments than in the control area. While agricultural development is an economic necessity in developing countries, the impacts on the natural landscape may result in genotoxic damage to the local fauna, such as bats. Over the medium to long term, then DNA damage may have an increasingly negative impact on the wellbeing of the local species.

The accumulation of 17 human pharmaceuticals (HPs) was investigated in the muscle of three fish species characteristic of the “Rio de la Plata Basin” with different feeding habits and of relevance for human consumption: Megaleporinus obtusidens, Salminus brasiliensis, and Prochilodus lineatus. Fish were sampled in fall and spring from 8 localities distributed along 500 Km of the Uruguay River. Atenolol and carbamazepine were the most frequently detected HPs (>50%), but at concentrations always below 1 μg/kg wet weight (w/w). Hydrochlorothiazide, metoprolol, venlafaxine, propranolol, codeine, and the carbamazepine metabolite, 2-hydroxycarbamazepine, were accumulated at higher levels showing maximum concentrations between 1 and 10 μg/kg (w/w), but infrequently (<50%). The other HPs were always below 1 μg/kg (w/w) and at frequencies lower than 50%. Distinctive accumulation patterns were observed among species at different trophic levels. However, biomagnification trends were not identified for any compound. The highest number and concentration of HPs were found in M. obtusidens (omnivorous), followed by P. lineatus (detritivorous), and lastly S. brasiliensis (piscivorous). The most recurrent HPs (i.e. carbamazepine and atenolol) were present in all species, but others exclusively in one. Geographical variations were only found for carbamazepine and atenolol in M. obtusidens and P. lineatus, showing higher concentrations in localities closer to the Rio de la Plata estuary. Differences in the HPs concentrations among seasons were not identified. Acceptable daily intake and predicted no effect concentrations would indicate that measured muscle concentrations in fish from the Uruguay River do not pose a serious risk for human consumption nowadays. Further studies will be necessary for assessing the potential adverse effects on studied fish species.

Microplastic (MP) has become ubiquitous in the marine environment. Its threat to marine organisms has been demonstrated under laboratory conditions, yet studies on wild populations still face methodological difficulties. We reviewed the methods used to separate MP from soft animal tissues and highlighted a lack of standardised methodologies, particularly critical for synthetic microfibres. We further compared enzymatic and a potassium hydroxide (KOH)-based alkaline digestion protocols on wild crabs (Carcinus aestuarii) collected from three coastal lagoons in the north Adriatic Sea and on laboratory-prepared synthetic polyester (PES) of different colour and polypropylene (PP). We compared the cost-effectiveness of the two methods, together with the potential for adverse quantitative or qualitative effects on MP that could alter the capability of the polymers to be recognised via microscopic or spectroscopic techniques. Only 5.5% of the 180 examined crabs contained MP in their gastrointestinal tracts, with a notably high quantitative variability between individuals (from 1 to 117 particles per individual). All MP found was exclusively microfibres, mainly PES, with a mean length (±SE) of 0.5 ± 0.03 mm. The two digestion methods provided comparable estimates on wild crabs and did not cause any visible physical or chemical alterations on laboratory-prepared microfibres treated for up to 4 days. KOH solution was faster and cheaper compared to the enzymatic extraction, involving fewer procedural steps and therefore reducing the risk of airborne contamination. With digestion times longer than 4 days, KOH caused morphological alterations of some of the PES microfibres, which did not occur with the enzymatic digestion. This suggests that KOH is effective for the digestion of small marine invertebrates or biological samples for which shorter digestion time is required, while enzymatic extraction should be considered as alternative for larger organisms or sample sizes requiring longer digestion times.

In this study, the bioaccumulation of perfluorinated compounds from a food web in Taihu Lake in China was investigated. The organisms included egret bird species, carnivorous fish, omnivorous fish, herbivorous fish, zooplankton, phytoplankton, zoobenthos and white shrimp. Isotope analysis by δ13C and δ15N indicated that the carnivorous fish and egret were the top predators in the studied web, occupying trophic levels intermediate between 3.66 and 4.61, while plankton was at the lowest trophic level. Perfluorinated carboxylates (PFCAs) with 9–12 carbons were significantly biomagnified, with trophic magnification factors (TMFs) ranging from 2.1 to 3.7. The TMF of perfluorooctane sulfonate (PFOS) (2.9) was generally comparable to or lower than those of the PFCAs in the same food web. All hazard ratio (HR) values reported for PFOS and perfluorooctanoate (PFOA) were less than unity, suggesting that the detected levels would not cause any immediate health effects to the people in Taihu Lake region through the consumption of shrimps and fish.

BPA is chemical pollutant of very high concern due to its toxicity to the environment and risks for human health. Environmental concern consists in BPA entrance into aquatic ecosystems due to acute and chronic toxicity to invertebrates and vertebrates. This study aimed to determine acute BPA toxicity to tropical estuarine-marine species of four trophic levels and integrate BPA toxicity values using species sensitivity distribution (SSD) analysis. Our hypothesis is that BPA toxicity increases towards higher trophic levels. Microalga (Tetraselmis sp.), zooplanktonic grazer (Artemia salina), deposit-feeder invertebrate (Heleobia australis), and omnivorous fish (Poecilia vivipara) were chosen as experimental models. Tetraselmis sp. showed the highest BPA tolerance, without a concentration-dependent response. Species sensitivity have increased from A. salina (LC₅₀,₉₆ₕ = 107.2 mg L⁻¹), followed by H. australis (LC₅₀,₉₆ₕ = 11.53.5 mg L⁻¹), to P. vivipara (LC₅₀,₉₆ₕ = 3.5 mg L⁻¹). Despite the toxicity hierarchy towards trophic levels, which partially supported our hypothesis, SSD did not evidence a clear pattern among estuarine-marine trophic groups. Our study disclosed the sensitivity of not yet investigated species to BPA and, in an integrative way, highlighted BPA toxic effects at different trophic levels. Although estimated acute hazardous concentration (HC5 = 1.18 mg L⁻¹) for estuarine and marine species was higher than environmentally relevant concentrations, sublethal adverse effects induced by BPA exposure may lead to unbalances in population levels and consequently affect the ecological functioning of tropical coastal systems.

Increasing heavy metal pollution in wetland ecosystems around the world pose significant health risks to waterbirds, especially the endangered species. We analyzed heavy metal pollution in bird foraging area of Caohai wetland in Guizhou Plateau (China), and used an integrated exposure risk model for assessing heavy metal (Cd, Pb, Cr, Ni, Zn, Sb) exposure risk in birds from the soil, water, plants and benthic invertebrates. There is considerable variation in the extent of heavy metal contamination across the different sampling sites, and Cd and Sb are the main contaminants. The mussel Anodonta showed greater heavy metal accumulation (except for Zn) compared to the snail species C. cathayensis. The different plant species also varied in terms of amount for accumulated heavy metals. The phytophagous together with omnivorous birds were exposed to Cd, Pb, Zn and Ni through plants rather than the soil, whereas the maximum Zn exposure in the omnivorous and carnivorous birds was through consumption of benthic invertebrates. Furthermore, the phytophagous black-necked cranes (Grus nigricollis) were less risk to heavy metal exposure compared to the omnivorous bar-headed goose (Anser indicus) and carnivorous ruddy shelducks (Tadorna ferruginea). The exposure risk of Cr (8.1) was highest, followed by Pb (5.1), Zn (3.8), Sb (1.0), Cd (0.33) and Ni (0.28). The heavy metal assessment heavy metal exposure risk for migratory birds should take into account the exposure from food and soil. Our findings provide new insights into developing measures to minimize heavy metal contamination in migratory birds.