While vegetable uptake of traditional metal contaminants is a well-studied pathway to human exposure and risk, a paucity of information exists on the uptake of emerging metal contaminants. This study evaluated the uptake of the Technology-critical elements (TCEs) gallium (Ga), germanium (Ge), niobium (Nb), tantalum (Ta), thallium (Tl), and rare earth elements (REEs) into lettuce cultivated in 21 European urban soils. For comparison, the uptake of cadmium (Cd) was also analysed. First, the uptake was predicted by multiplying soil concentrations with previously established bioconcentration factors (BCFs). Subsequently, multiple regression models incorporating geochemical variables as predictors were used to determine whether prediction accuracy could be improved. A “3-predictor model” incorporated soil TCE concentration, pH, and organic matter (OM), and a “7-predictor model” added data on clay content and the soil concentrations of Fe, Al, and Mn as well. With the exception of Cd, Ge, and Tl, the BCF approach provided unsatisfactory predictions (R2 < 0.5), while the 7-predictor models yielded the best predictions, even when accounting for the greater number of predictors. While the most important predictors of uptake varied somewhat between the TCEs, the concentrations of TCEs in the soil generally explained the largest proportion of the variation. The least influential predictors in our dataset were [Mnsoil], [Fesoil], and soil OM. Incorporating geochemical data generally improved the predictions of uptake by lettuce, and these findings underscore the need for more detailed characterisations of the uptake potential of TCEs by food plants and subsequent consequences for human health.

Human activities increase turbidity in aquatic environments worldwide, which often affects fish behaviour. However, predicting how species react to higher turbidity remains difficult, as responses vary depending on the species, their ecology and the ecosystem. It is thus important to improve our understanding of the responses of fishes living in ecosystems experiencing recent increases in turbidity, especially those with unique species compositions where biodiversity is most vulnerable. One such ecosystem is Lake Tanganyika in East Africa, which is home to a diverse fish community with a high degree of endemism. In this study, we conducted a laboratory experiment with the territorial cichlid, Neolamprologus pulcher, which is endemic to Lake Tanganyika, to investigate the effects of increased turbidity on territorial and exploratory behaviour. We found that moderate increases in turbidity led to reduced territory defence, decreased exploration and increased time spent in shelters. Given that these fish live in large colonies, feed on planktonic particles in the water column and defend their territory against conspecific and heterospecific intruders, these behavioural changes are likely to have substantial implications for their social structure and reproduction in their native environments. Our study raises important questions about whether these effects will persist in the long term as human activities are likely to continue to increase turbidity in the lake over the coming decades and whether the responses to turbidity affect the community composition of fishes in Lake Tanganyika.

Trophically transmitted parasites have life cycles that require the infected host to be eaten by the correct type of predator.Such parasites should beneft from an ability to suppress the host’s fear of predators, but if the manipulation is imprecise theconsequence may be increased predation by non-hosts, to the detriment of the parasite. Three-spined sticklebacks (Gasterosteus aculeatus) infected by the cestode Schistocephalus solidus express reduced antipredator behaviours, but it is unknownwhether this is an example of a highly precise manipulation, a more general manipulation, or if it can even be attributedto mere side efects of disease. In a series of experiments, we investigated several behaviours of infected and uninfectedsticklebacks. As expected, they had weak responses to simulated predatory attacks compared to uninfected fsh. However,our results suggest that the parasite induced a general fearlessness, rather than a precise manipulation aimed at the correctpredators (birds). Infected fsh had reduced responses also when attacked from the side and when exposed to odour from afsh predator, which is a “dead-end” for this parasite. We also tested whether the reduced anti-predator behaviours were meresymptoms of a decreased overall vigour, or due to parasite-induced hunger, but we found no support for these ideas. Wepropose that even imprecise manipulations of anti-predator behaviours may beneft parasites, for example, if other behavioursare altered in a way that increases the exposure to the correct predator.

We analyzed fatal dog attacks in Europe 1995-2016 using official death cause data from Eurostat. The data comprised the number of fatalities assigned The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) code W54 "bitten or struck by dog", which includes deaths due to direct attacks but which excludes many complications following dog bites, such as rabies. In 2016, dogs killed 45 Europeans, which translates to an incidence of 0.009 per 100,000 inhabitants. This is comparable to estimates from the USA (0.011), and Canada (0.007), but higher than Australia (0.004). The number of European fatalities due to dog attacks increased significantly at a rate of several percent per year. This increase could not be explained by increases in the human or the dog populations. By taking all fatalities reported 1995-2016 into account, we investigated the effects of age, gender and geography. First, children, including infants, were common victims, but also middle-aged and the elderly, while people between ages 10 and 39 were rarely killed by dogs. Second, boys and men were overrepresented, but only in certain age groups and in certain parts of Europe. Third, there were large national and regional differences, both in the effects of gender and in incidences, which ranged from 0 to 0.045 per 100,000 inhabitants. This study of dog-related fatalities at a European level is the first of its kind and forms a basis for more detailed, national studies.

Soil pollution constitutes one of the major threats to public health, where spreading to groundwater is one of several critical aspects. In most internationally adopted frameworks for routine risk assessments of contaminated land, generic models and soil guideline values are cornerstones. In order to protect the groundwater at contaminated sites, a common practice worldwide today is to depart from health risk-based limit concentrations for groundwater, and use generic soil-to-groundwater spreading models to back-calculate corresponding equilibrium levels (concentration limits) in soil, which must not be exceeded at the site. This study presents an extensive survey of how actual soil and groundwater concentrations, compiled for all high-priority contaminated sites in Sweden, relate to the national model for risk management of contaminated sites, with focus on As, Cu, Pb and Zn. Results show that soil metal concentrations, as well as total amounts, constitute a poor basis for assessing groundwater contamination status. The evaluated model was essentially incapable of predicting groundwater contamination (i.e. concentrations above limit values) based on soil data, and erred on the "unsafe side" in a significant number of cases, with modelled correlations not being conservative enough. Further, the risk of groundwater contamination was almost entirely independent of industry type. In essence, since neither soil contaminant loads nor industry type is conclusive, there is a need for a supportive framework for assessing metal spreading to groundwater accounting for site-specific, geochemical conditions.

Phenotypic flexibility may incur a selective advantage in changing and heterogeneous environments, and is increasingly recognized as an integral aspect of organismal adaptation. Despite the widespread occurrence and potential importance of rapid and reversible background-mediated color change for predator avoidance, knowledge gaps remain regarding its adaptive value, repeatability within individuals, phenotypic correlates, and whether its expression is context dependent. We used manipulative experiments to investigate these issues in two fish species, the three-spined stickleback (Gasterosteus aculeatus) and nine-spined stickleback (Pungitius pungitius). We sequentially exposed individuals to dark and light visual background treatments, quantified color change from video recordings, and examined associations of color change with phenotypic dimensions that can influence the outcome of predator-prey interactions. G. aculeatus expressed a greater degree of color change compared to P. pungitius. In G. aculeatus, the color change response was repeatable within individuals. Moreover, the color change response was independent of body size but affected by sex and boldness, with males and bolder individuals changing less. Infection by the parasite Schistocephalus solidus did not affect the degree of color change, but it did modulate its association with sex and boldness. G. aculeatus adjusted the expression of color change in response to predation risk, with enhanced color change expression in individuals exposed to either simulated attacks, or olfactory cues from a natural predator. These results provide novel evidence on repeatability, correlated traits, and context dependence in the color change response and highlight how a suite of factors can contribute to individual variation in phenotypic flexibility.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

Both between- and within-individual variation in behaviour can be important in determining mating opportunities and reproductive outcomes. Such behavioural variability can be induced by environmental conditions, especially if individuals vary in their tolerance levels or resource allocation patterns. We tested the effects of exposure to different salinity levels on male investment into two important components of mating success-intrasexual aggression and intersexual courtship-in a fish with a resource defence mating system, the desert goby, Chlamydogobius eremius. We found that males that were more aggressive to rivals also exhibited higher rates of courtship displays towards females. Contrary to predictions, this positive relationship, and the consistency of the two behaviours, were not affected by the salinity treatment, despite the physiological costs that high salinity imposes on the species. Moreover, over the entire data-set, there was only a marginally non-significant tendency for males to show higher levels of aggression and courtship in low, than high, salinity. The positive correlation between male aggression and courtship, independent of the physiological demands of the environment, suggests that males are not inclined to make contrasting resource investments into these two key reproductive behaviours. Instead, in this relatively euryhaline freshwater species, typical investment into current reproductive behaviours can occur under a range of different salinity conditions.