Microplastics exposure could be detrimental to marine organisms especially under high concentrations. However, few studies have considered the multiphasic nature of marine invertebrates' life history and investigated the impact of experiencing microplastics during early development on post-metamorphic stages (legacy effect). Many planktonic larvae can feed selectively and it is unclear whether such selectivity could modulate the impact of algal food-sized microplastic. In this two-stage experiment, veligers of Crepidula onyx were first exposed to additions of algae-sized micro-polystyrene (micro-PS) beads at different concentrations, including ones that were comparable their algal diet. These additions were then either halted or continued after settlement. At environmentally relevant concentration (ten 2-μm microplastic beads ml⁻¹), larval and juvenile C. onyx was not affected. At higher concentrations, these micro-PS fed larvae consumed a similar amount of algae compared to those in control but grew relatively slower than those in the control suggesting that ingestion and/or removal of microplastic was/were energetically costly. These larvae also settled earlier at a smaller size compared to the control, which could negatively affect post-settlement success. Juvenile C. onyx receiving continuous micro-PS addition had slower growth rates. Individuals only exposed to micro-PS during their larval stage continued to have slower growth rates than those in the control even if micro-PS had been absent in their surroundings for 65 days highlighting a legacy effect of microplastic exposure.

Dietary fish oil used in aquafeed transfers marine pollutants to farmed fish. However, the entire transfer route of marine pollutants in dietary fish oil from ocean to table fish has not been tracked quantitatively. To track the entire transfer route of marine pollutants from wild fish to farmed fish through dietary fish oil and evaluate the related human health risks, we obtained crude and refined fish oils originating from the same batch of wild ocean anchovy and prepared fish oil-containing purified aquafeeds to feed omnivorous lean Nile tilapia and carnivorous fatty yellow catfish for eight weeks. The potential human health risk of consumption of these fish was evaluated. Marine persistent organic pollutants (POPs) were concentrated in fish oil, but were largely removed by the refining process, particularly dioxins and polychlorinated biphenyls (PCBs). The differences in the POP concentrations between crude and refined fish oils were retained in the fillets of the farmed fish. Fillets fat content and fish growth were positively and negatively correlated to the final POPs deposition in fillets, respectively. The retention rates of marine POPs in the final fillets through fish oil-contained aquafeeds were 1.3%–5.2%, and were correlated with the POPs concentrations in feeds and fillets, feed utilization and carcass ratios. The dietary crude fish oil-contained aquafeeds are a higher hazard ratio to consumers. Prohibiting the use of crude fish oil in aquafeed and improving growth and feed efficiency in farmed fish are promising strategies to reduce health risks originating from marine POPs.

The anthropogenic contamination of water bodies with metals via fertilizer, industrial sewage and urban wastewater has resulted in widespread problems in aquatic organisms, but also poses a risk to consumer health. Shellfish from coastal and estuarine environments bioaccumulate toxic metals in their tissues due to their ability to concentrate inorganic contaminants several orders of magnitude above ambient levels. The aim of this study was to evaluate the presence of trace elements in adult specimens of indigenous clams (Ruditapes decussatus). To this end, wild clams were collected from four different brackish areas of Sardinia (Western Mediterranean Sea, Italy) devoted to extensive aquacultural practices. The concentration of 16 trace elements (Al, Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, Tl and Zn) in the tissues of the clams was quantified. The legal limits set by European Regulations for cadmium; mercury and lead were never exceeded. However, unexpectedly high values for aluminium and iron (mean 207 mg kg⁻¹ and 113 mg kg⁻¹ wet weight) were found in Santa Gilla lagoon, which is close to industrial settlements and had the highest values for the majority of chemical elements investigated. The highest values of the metalloid arsenic (As) were reported in the Porto Pozzo and San Teodoro lagoons (9.6 and 6.8 mg kg⁻¹ w.w., respectively). The clam R. decussatus confirmed the capacity of bivalves as suitable bioindicators of trace elements pollution. Further investigations are necessary for constant monitoring of clams, 32 which constitute an important traditional resource for the fishing activity in Sardinia.

Pollen allergy risk is modified by air pollutants, including ozone, but the chemical modifications induced on pollen grains are poorly understood. Pollen lipidic extract has been shown to act as an adjuvant to the allergenic reaction and therefore, the modification of lipids by air pollutants could have health implications. Birch pollen was exposed in vitro to ozone to explore the reactivity of O₃ on its surface and on its lipidic fraction. Uptake coefficients of ozone were determined for ozone concentration of 117 ppb on the surface of native birch pollen (8.6 ± 0.8 × 10⁻⁶), defatted pollen (9.9 ± 0.9 × 10⁻⁶), and for crushed pollen grains (34±3 × 10⁻⁶). The mass of ozone uptaken was increased by a factor of four for crushed pollen compared to native pollen showing a higher susceptibility to ozone of cytoplasmic granules and broken pollen grains. A total mass of extractible lipids of 27 mg per gram of birch pollen was found and a fraction of these lipids was identified and quantified (fatty acids, alkanes, alkenes and aldehydes). The distribution of lipids was modified by ozone exposure of 115 and 1000 ppb for 16 h with the following reactivity: consumption of alkene, formation of aldehydes and formation of nonanoic acid and octadecanoic acid. The quantity of ozone trapped in the lipidic fraction during 15 min at 115 ppb is enough to contribute to the reactivity of one-third of the alkenes demonstrating that pollen could be susceptible to an atmospheric increase of ozone concentration even for a very short duration complicating the understanding of the link between pollen allergy and pollution.

The transfer of pollutants from chemical fertilizers through food webs within cropland is well documented; however, its impacts on the wild animals that forage on croplands but roost in other locations remain poorly understood. The potential for this cross-ecosystem ‘spillover’ of pollutants is greatest for bats, some of which exploit urban settlements as roosting niches but must travel long distances to reach croplands as foraging niches. Here, we used hairs from a colony of insectivorous bats, Chinese Noctule (Nyctalus plancyi), from an urban area in Southwest China to assess whether exposure to heavy metals/metalloids by the bats varied from 1975 to 2016. Historical changes occurred in hair cadmium (Cd) concentrations in adult females, which was exclusively explained by the regional fertilizer application intensity (FAI), even considering the potential impacts of Cd emissions in urban areas, as indicated by camphor trees (Cinnamomum camphora) near the bats' roosting niche, and the potential impacts of Cd in industrial wastewater, as documented in authorized databases. Therefore, the data from this bat colony, as urban dwellers, indicates Cd accumulation and cross-ecosystem transfer from rural croplands to an urban area.

Chemical pollution is a growing issue for ocean ecosystems, threatening especially apex predators because they bioaccumulate persistent chemical pollutants such as non-essential trace elements. The trophic position is thus a key aspect when assessing the impacts of environmental pollution in marine organisms. Here we investigate the differences in the concentrations of essential (Cu, Cr, Se, and Zn) and non-essential elements (Hg, Al, As, Cd, and Sr), in muscular and hepatic tissues of four sympatric non-migratory seabirds (namely Sula leucogaster, Larus dominicanus, Fregata magnificens, and Thalasseus acuflavidus), which were found stranded along the Brazilian coast. The observed hepatic and muscular interspecific differences in elemental concentrations indicated that these sympatric seabirds are differently exposed to persistent contaminants circulating in the food web due to differences with respect to known feeding behaviours and prey preferences. Moreover, we found a consistent co-accumulative relationship between Se and Hg molar levels in liver tissues with mean Se:Hg molar ratio above 1. This relationship supports previous studies indicating that Se, via the formation of SeHg complexes, plays an essential biochemical role in the detoxification process of methyl mercury in seabirds. Our results suggest that feeding behaviour is an important factor associated to the interspecific differences of trace element concentrations in seabirds. However, traits other than feeding preferences (e.g. age) may also play an important role in the accumulation of these elements.

Smoking activities were recognized as a main risk factor for population. Indeed, mainstream smoke aerosol is directly inhaled by smokers then delivering harmful compounds in the deepest regions of the lung. In order to reduce the potential risk of smoking, different nicotine delivery products have been recently developed. The latest device released is an electrically heated tobacco system (iQOS®, Philip Morris) which is able to warm the tobacco with no combustion. In the present paper a dimensional and volatility characterization of iQOS-generated particles was performed through particle number concentration and distribution measurements in the mainstream aerosol. The experimental analysis was carried out through a condensation particle counter, a fast mobility particle sizer and a thermo-dilution sampling system allowing aerosol samplings at different temperatures. Estimates of the particle surface area dose received by smokers were also carried out on the basis of measured data and typical smoking patterns.The particle number concentrations in the mainstream aerosols resulted lower than 1 × 108 part. cm−3 with particle number distribution modes of about 100 nm. Nonetheless, the volatility analysis showed the high amount of volatile fraction of iQOS-generated particles, indeed, samplings performed at 300 °C confirmed a significant particle shrinking phenomena (modes of about 20 nm). Anyway, the particle number concentration does not statistically decrease at higher sampling temperatures, then showing that a non-volatile fraction is always presents in the emitted particles. The dose received by smokers in terms of non-volatile amount of particle surface area was equal to 1–2 mm2 per puff, i.e. up to 4-fold larger than that received by electronic cigarette vapers.

Potentially toxic elements are widespread soil contaminants, whose occurrence could entail a concern for human health upon ingestion of fruit and vegetables harvested in a polluted area. This work set out to evaluate the concentrations of lead and cadmium as well as the levels of thirteen heavy metals for which a limit value is yet to be established by the food safety authorities, in order to perform a risk characterization related to the dietary intake of these metals and to provide a scientific opinion with wider relevance in the light of current worldwide regulatory issues. The sampling consisted of fruit and vegetables grown in a potentially contaminated area of southern Italy due to the illegal dump of hazardous wastes. An evaluation of the dietary exposure through the calculation of the Hazard Index (HI), the Maximum Cumulative Ratio (MCR) and the Target Cancer Risk (TCR) was adopted to this end. The results revealed that about the 30% of samples showed quantifiable levels of chemicals and no significant difference emerged between the potentially polluted area and the nearby cities that were selected as a control landfill site. The overall risk characterization for non-carcinogenic endpoints showed that the HI did not reach unsafe values, except for a small number of samples mainly because of aberrant occurrences and, in any case, the cumulative toxicity was mainly driven by thallium and vanadium. As far as the carcinogenic effects of arsenic are concerned, the distribution of TCR values broadly lay below the safety threshold; a certain percentage of data, however, exceeded this limit and should be taken into account for the enforcement of future regulatory thresholds.

Long-term genotoxic effects of two auxinic herbicide formulations, namely, the 58.4% 2,4-dichlorophenoxyacetic acid (2,4-D)-based DMA® and the 57.7% dicamba (DIC)-based Banvel® were evaluated on Cnesterodon decemmaculatus. Primary DNA lesions were analyzed by the single-cell gel electrophoresis methodology. Two sublethal concentrations were tested for each herbicide corresponding to 2.5% and 5% of the LC50₉₆ₕ values. Accordingly, fish were exposed to 25.2 and 50.4 mg/L or 41 and 82 mg/L for 2,4-D and DIC, respectively. Fish were continuously exposed for 28 days with replacement of test solutions every 3 days. Genotoxicity was evaluated in ten individuals from each experimental point at the beginning of the exposure period (0 day) and at 7, 14, 21 and 28 days thereafter. Results demonstrated for first time that 2,4-D-based formulation DMA® induced primary DNA strand breaks after 7–28 days exposure on C. decemmaculatus regardless its concentration. On the other hand, DIC-based formulation Banvel® exerted its genotoxic effect after exposure during 7–14 days and 7 days of 2.5 and 5% LC50₉₆ₕ, respectively. The present study represents the first evidence of primary DNA lesions induced by two widely employed auxinic herbicides on C. decemmaculatus, namely 2,4-D and DIC, following long-term exposure.

Most cities in China experience frequent PM₂.₅ pollution, in relation to unfavorable planetary boundary layer (PBL) conditions. Partly due to the limited appropriate PBL observations, the explicit relationships between PBL structure/process and PM₂.₅ pollution in China are not yet clearly understood. Using the fine-resolution sounding measurements from 2014 to 2017, the relationships between boundary layer height (BLH) and PM₂.₅ pollution in China were systematically examined. Four regions of interest (ROIs) featured with dense population and heavy pollution were studied and compared, including Northeast China (NEC), North China Plain (NCP), East China (EC), and Sichuan Basin (SCB). From 2014 to 2017, the heaviest PM₂.₅ pollution happened in NCP with an annual average concentration of 84 μg m⁻³, followed by NEC (60 μg m⁻³), SCB (57 μg m⁻³), and EC (54 μg m⁻³). Correlation analyses revealed a significant anti-correlation between BLH and daily PM₂.₅ concentrations across China, independent of ROIs. During an annual cycle, the pollution was heaviest in winter, followed by fall and spring, and reached its minimum in summer. Such a seasonal variation of pollution was not only modulated by the emissions, but also the seasonal shifts of BLH. The low BLH in winter was often associated with strong near-surface thermal stability. Moreover, certain synoptic conditions in winter can exacerbate the pollution, leading to concurrent drops of BLH and synchronous increases of PM₂.₅ concentration in different cities of a ROI. In NCP and SCB, the mountainous terrains could further worsen the pollution by blocking effects and lee eddies.