Ocean acidification threatens coral reefs by reducing seawater pH and carbonate saturation state. Crustose coralline algae are particularly vulnerable because their high-magnesium calcite skeletons dissolve more readily than coral aragonite skeletons. However, this dissolution may increase alkalinity and buffer reef-water chemistry. Here we show, using repeated low-tide observations and in situ incubations in a shallow reef system in the southern Great Barrier Reef, that reef-water pH varies by more than one unit over the day (7.47 – 8.61), reaching levels comparable to those projected for the end of this century. Nighttime respiration promotes dissolution of high-magnesium calcite produced by crustose coralline algae, increasing alkalinity and helping maintain seawater supersaturated with respect to aragonite. At the same time, isolated coral incubations experience a greater decline in pH and aragonite saturation state in the absence of this buffering effect. These findings suggest that high-magnesium calcite-producing communities may help partially buffer reefs against future acidification. Crustose coralline algae overlying reef structures can reduce coral dissolution, especially at night-time, according to in-situ carbonate chemistry data from the Great Barrier Reef.

International shipping is the backbone of the global economy with ~80% of the world’s trade (by volume) transported by ship. The potential environmental impacts of this multi-billion-dollar industry have received considerable attention, particularly emissions into air and sea. Many of these large commercial vessels lay at anchor for extended periods while awaiting their turn to enter port, and yet the impacts associated with anchoring remain virtually unexamined. Anchors can exceed 20 tonnes, with chains up to hundreds of metres in length and individual links weighing up to 200kg; there is potential for significant effects on seafloor biota where anchoring is concentrated. Filling knowledge gaps in deep-water wave-exposed environments is logistically challenging and expensive. To do so we used sediment grabs collected offshore from the Port of Newcastle (SE Australia) – the world’s largest coal export terminal – to sample infaunal assemblages in anchor-affected locations relative to reference locations (30 to 55m water depth). Polychaetes and crustaceans were the most abundant biota in the samples (~85%), whereas molluscs were very low in abundance (<3%), despite being well represented in terms of diversity (11 families of bivalves and 9 families of gastropods). Invertebrate abundance almost doubled in areas exposed to anchoring compared to reference areas. In contrast, invertebrate diversity declined with increasing anchoring activity, however this relationship was weak. Importantly, we observed major shifts in the overall invertebrate assemblage at anchored-affected locations – with reductions in suspension feeders mirrored by increases in scavengers and predators. We assert that suspension feeders were negatively impacted by sediment mobilisation or direct physical damage from anchor chains, while opportunistic scavengers and mobile predators benefitted from this disturbance. We contend that anchor disturbance is a global issue given burgeoning marine trade. Data on the effects of anchoring are urgently required to better inform the management of environments regularly used as anchorages.

Environmental context Several predators that eat Antarctic krill may be unintentionally ingesting toxic substances. Studying aspects of krill life to understand the effects of potential increases in Antarctic mercury (Hg) availability revealed that seasons, locations and individual size influence krill Hg concentration. Despite increasing human presence (potential Hg sources) in Antarctica, krill Hg content remains stable, and evidence suggests that Hg accumulates in predators by both short (krill-based) and longer food chains. Rationale Mercury (Hg) is passively assimilated from the water by phytoplankton, accumulated by lower trophic levels species, and biomagnified along food chains. Any increases in its bioavailability in Antarctic waters could endanger the survival of vulnerable top predators. With Antarctic food webs reliant on krill, we must understand the temporal, spatial and biological variability in their Hg concentration to forecast ecosystem-wide impacts of rising Hg levels. Methodology We sampled krill fortnightly from South Georgia, South Orkney Islands and West Antarctic Peninsula between December 2013 and September 2019 (excluding October and November months). Individuals were weighed, sexed and analysed for Hg. We assessed the importance of biological (krill size, sex and life stage) and environmental (location, time and chlorophyll-a concentration) parameters on krill Hg concentrations with generalised linear models, analyses of variance, Gaussian linear models and vector autoregressive modelling. Results Temporal variation explained most of the differences in krill Hg concentrations, with location and individual size also contributing to the variability. Subsurface chlorophyll-a concentrations and the affinity of methylmercury to sulfhydryl groups of some proteins, rather than krill fatty acid content, were likely the drivers of observed annual cycles. Discussion Antarctic krill Hg concentrations have remained stable since the 1990s, although our measurements were lower than most. Such a historic baseline is indispensable for continued monitoring of Antarctic ecosystems. Krill is considered a key prey species, but our findings and those of biomagnification studies suggest that there may be a gap in our understanding of trophic transfer and accumulation of Hg in some top predators. Future biomagnification studies would benefit from conducting mass balance models.

Excessive dietary metal intake from crops grown on contaminated urban dumpsites poses a global health risk to consumers. We evaluated the health risk to adult and child consumers from dietary exposure to metals and metalloids in crops cultivated at the Mbale (Uganda) dumpsite centre. Thirteen crop types grown on the dumpsite soil were sampled and analyzed for concentrations of 11 metals: Fe, Al, Zn, Mn, Cu, Pb, Cr, Hg, Co, Ni, Cd, and two metalloids: Se and As. Different proportions of the crops were combined into 12 meal classes to simulate the diets of residents and estimate noncancer and cancer risks. The findings indicated that most individual crop types and simulated diets lacked sufficient selenium for bodily functions. Furthermore, their metal accumulations exceeded the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) permissible limits (mg/kg) for Al (20), Fe (100), Ni (10), Cu (20), Mn (10), Pb (0.3), Se (0.05), and Zn (99.4). The four most abundant metals in the various crop types and diets were Al, Fe, Mn, and Zn. A positive correlation between the metals in the crops indicated a common origin, which could possibly be the dumpsite soil. The chronic dietary intake (CDI) of metals was higher in children, and thus children faced higher noncancer and cancer risks compared with adults. The overall CDI values for each metal ranged from 0.000718 to 2.171 in adults, and 0.00125 to 3.781662 in children, which is approximately 1.74 times higher in children than in adult consumers. The noncancer and cancer risks ranged from moderate to high with Co, Cr, Fe, Mn, and Zn being mostly responsible for the high noncancer risks, and Al being the predominant contributor to cancer risks. The total noncancer risk levels equally ranged from moderate (1.4-3.3) for adults, and moderate to high (2.4-5.7) for children; the cancer risks were moderate to high in adults, with Al contributing to between 68% and 92% of the total risks across the 12 meal classes. Overall, CDI values and noncancer and cancer risks were all higher in children than in adults. The vegetables Amaranthus hybridus, Vigna unguiculate, Amaranthus dubius, and Cucurbita maxima significantly contributed to the high noncancer risk to both adults and children, particularly when they constituted 40% or more of the meal. Four additional vegetables (Cocorhrous olitorous, Brassica oleracea, Amaranthus cruentus, and Gynandropsis gynandra) also posed a high risk to children when consumed in large quantities. Our results highlight the urgent need to develop regulatory frameworks and/or rigorously enforce existing land and food governance policies to protect consumers' health from unsafe metal concentrations in crops grown on dumpsites. Environ Toxicol Chem 2024;43:2628-2644. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Internal variability changes in soil surface temperature and reflective radiation drove climate to change and vice versa over all time scales. This study investigates the heat flux components and the climate variables that drive the change in surface soil temperature down to 15.0 cm. We analyze the correlations of energy and radiation components to climate variables by coding principle component analysis (PCA) and finding the radiative forcing of atmosphere-energy-climate-soil continuum systems using datasets derived from ERA5 and NCEP/NCAR projections. The vectors contributing to the continuum were the shortwave, net solar radiation, and sensible flux are the main drivers. The average 72-year shortwave in the study locations was − 190.63 W/m2. Because of the upwelling radiation to the atmosphere, the longwave flux did not exceed the shortwave over the study’s location. The sensible heat flux was the lowest in the northwestern highlands (approximately 32 Watt/m2) and the highest range during summer was 150–180 Watt/m2 over the country. This variability in net radiation partitioning led to changes in surface warming and the responding climate. This study found that the average monthly soil surface temperature bound was 10–20 °C from November to March at all locations except for Amman and Ruwaished. The calculated soil heat storage is positive all year in the Dead Sea with an annual average of 76.53 W/m2. The lowest storage heat was in Amman with an annual average of − 44.42 W/m2. The anomalies of annual ERA5 reanalysis of main climate contributors extended from (− 5.46 to + 5.53 °C), (− 5.66 to + 4.36 °C), (− 1.3 to 2.87 mm/day), and around (− 25.97

Selenium (Se) is an essential element for aquatic organisms as well as humans. It can be toxic to organisms depending on its concentration and chemical speciation; thus, considerable efforts have been made to unravel the biogeochemical cycling of Se in aquatic systems. Mathematical models provide an important tool to better understand the fate of Se in different environment compartments. However, a comprehensive review of modeling Se in aquatic systems with current challenges and opportunities is missing. To fill this gap, we firstly summarize the processes governing Se cycling in aquatic systems, including particle adsorption and desorption, diffusion, biological uptake, redox reactions, and volatilization. Then, we critically review the available models, identifying the compartments modelled, environmental factors considered, and the Se species and geochemical processes used in each model, providing an assessment of their advantages and limitations. Data availability for modeling studies is investigated, highlighting how to better quantify the redox reactions, estimate of Se loadings, and mass balance. For the modeling of Se cycling in aquatic systems, the ability of the models to link sources to biota concentrations under a range of hydrodynamic conditions and with mechanistic representations of transport, transformation, and uptake processes is required. The majority of the current models can conduct this task; however, to better present the uptake processes of Se in the food web, two-way coupling of the Se cycling model with a food web model is recommended.

Environmental context Arsenic's effect on rice plant health is a critical environmental issue. This study reveals that rice plants absorb inorganic arsenic and dimethylarsenic differently, with dimethylarsenic posing a greater threat to rice plant health. These findings contribute to our understanding of arsenic toxicity in plants, highlighting the need for further research into detoxification strategies for dimethylarsenic.Rationale Arsenic toxicity in plants, particularly the effects of different arsenic species, is not well understood. This study investigated the response of juvenile rice plants, grown hydroponically, to prolonged exposure to inorganic and dimethyl arsenic species. The hydroponic system removed complexity by eliminating soil processes.Methodology The accumulation of inorganic As (Asi) and dimethylarsenic (DMA) in hydroponically grown rice was monitored for plants exposed to different As concentrations (0-6.7 mu mol L-1). Dose-response experiments were conducted to compare the effects of As species on plant health in terms of growth.Results Plants absorb Asi and DMA linearly, with faster Asi uptake than DMA. Asi exposure leads to higher As concentrations in roots and shoots than DMA. Despite more Asi in roots, its translocation to shoots is lower. Asi and DMA accumulation in shoots remains relatively constant at lower As concentrations. At the highest As concentration, more Asi and DMA accumulate in shoots. Exceeding 1.6 mu mol L-1, Asi and DMA reduce plant height and biomass. Asi-exposed plants show little health differences except at the highest concentrations. DMA-exposed plants show more unhealthy instances above 1.6 mu mol L-1.Discussion DMA's lower uptake rate aligns with other rice species results, as do lower shoot and root translocation factors. Near constant As concentrations in shoots at low Asi concentrations suggest an Asi exposure threshold before plants lose their As sequestration ability, resulting in reduced growth. DMA exposure increases the number of unhealthy plants, suggesting a greater potential effect on plant health and fitness, differing from Asi-induced stress.

Rationale. Rice is inherently efficient at accumulating arsenic (As) due to it being grown under anaerobic conditions. Arsenic in rice plants can pose a significant risk to human health. In this study we aim to determine if two agronomic practices, i.e. straw and nitrogen addition to rice paddies, influence the bioavailability of different As species within the soil and their incorporation in the various components of the rice plant and whether these practices lead to straighthead disease. Methodology. A field trial was conducted to grow commercially grown rice varieties with the application of wheat straw and nitrogen individually and in combination. Results. The incorporation of straw into the soil resulted in the formation of dimethyl arsenic (DMA) and an increase of As content in the grain as DMA. DMA accumulated linearly with total As concentration in the grain to become the major As species, whereas inorganic arsenic (Asi) plateaued at 0.2 mu g g(-1). Discussion. Rice plants cannot control the accumulation and distribution of DMA within the plant, and DMA uptake increases the severity of straighthead disease. The plants with straighthead disease recorded higher DMA concentrations in the husks and leaves when compared to healthy plants. This study showed that rice has some capacity to control Asi concentrations in the grain, whereas DMA accumulation is unregulated. Straw incorporation into soil promotes DMA formation and uptake into rice; this agronomic practice should be avoided.

Deep-sea hydrothermal vent communities, revealing patterns of niche partitioning, live in a limited area char-acterised by sharp physico-chemical gradients. In this study, we investigated carbon, sulfur, nitrogen stable isotopes as well as arsenic (As) speciations and concentrations for two snails (Alviniconcha sp. and Ifremeria nautilei) and a crustacean, (Eochionelasmus ohtai manusensis), occupying distinct niches in the hydrothermal vent field of the Vienna Woods, Manus Basin, Western Pacific. delta 13C values of Alviniconcha sp. (foot), I. nautilei (foot and chitin) and E. o. manusensis (soft tissue) are similar, from-28 to-33%o (V-PDB). The delta 15N values of Alvi-niconcha sp. (foot and chitin), I. nautilei (foot and chitin) and E. o. manusensis (soft tissue) range from 8.4 to 10.6%o. The delta 34S values of Alviniconcha sp. (foot and chitin), I. nautilei (foot) and E. o. manusensis (soft tissue) range from 5.9 to 11.1%o. Using stable isotopes, for the first time, we inferred a Calvin-Benson (RuBisCo) metabolic pathway for Alviniconcha sp. along with the presence of gamma-Proteobacteria symbionts for the Vienna Woods communities. For I. nautilei, a feeding pattern is proposed with gamma-Proteobacteria symbiosis and a Cal-vin-Benson-Bassham diet with mixotrophic feeding. E. ohtai manusensis is filtering bacteria with a CBB feeding strategy, with delta 15N values indicating possible higher position in the trophic chain.Arsenic concentrations in the dry tissue of Alviniconcha (foot), I. nautilei (foot) and E. o. manusensis (soft tissue) are high, from 4134 to 8478 mu g/g, with inorganic As concentrations of 607, 492 and 104 mu g/g, respectively and dimethyl arsenic (DMA) concentrations of 11.12, 0.25 and 11.2 mu g/g, respectively. Snails occurring in a vent proximal position have higher As concentration than barnacles, a pattern not observed for S concentrations. Arsenosugars were not put in evidence indicating that the available organic material for the vent organisms are not surface derived.

The effects of multigenerational Cu exposure on the freshwater gastropod Isidorella newcombi were investigated . Snails were exposed to a range of treatment-specific Cu concentrations in the parental to F 2 generations, and a common Cu concentration in the F 3 generation. In the parental to F 2 generations, some general responses to 3 days Cu exposures included reduced survival and feeding in snails exposed to higher Cu concentrations. This suggested that the snails exposed to the high Cu concentration were experiencing Cu-induced stress that may apply selection pressure. In the F 3 generation, when all treatments were exposed to a common Cu concentration, increased survival was correlated with the pre-exposure Cu concentration history. Snails that had been pre-exposed to Cu also displayed reduced stress at a sub-lethal level, indicated by lower lysosomal destabilisation (LD). Mortality and LD responses in the F 3 generation were not related to Cu tissue concentrations, indicating increased tolerance and reduced stress were not related to changes in Cu bioaccumulation. Total antioxidant capacity increased in the higher Cu concentration pre-exposure treatments which could be associated with lower Cu-induced stress, however, this is not supported by the oxidative damage marker lipid peroxidation, which also increased. While Cu tissue concentrations and oxidative stress markers were assessed to determine underlying reasons for increased tolerance in snails from a population with a multi-generational exposure history to Cu, the results were not conclusive. Despite this, it was demonstrated through increased survival and reduced LD that Cu tolerance can develop over a short evolutionary time scale.

Environmental context Arsenic is a globally distributed element, occurring in various chemical forms with toxicities ranging from harmless to highly toxic. We conducted 48-h cell culture experiments under batch and continuous conditions using the ubiquitous marine unicellular alga Dunaliella tertiolecta and evaluated the alga’s arsenic metabolome over time. We found that the alga first methylates the inorganic As taken up from the surrounding water, and then further metabolises the intermediate simultaneously into more complex organo-arsenic molecules like sugars and lipids. These time series experiments are valuable pieces in the puzzle of how algae bio-metabolise arsenic, and in our understanding of the global arsenic cycle. Rationale The uptake of arsenate by algae from oceanic waters and its transformation to arsenosugars and arsenolipids is well established, but the biosynthetic pathways remain largely unknown. Methodology We investigated these pathways by using time-series experiments over 48 h to follow the formation of organoarsenic species from arsenate-enriched medium (15 µg As L−1) by the unicellular alga Dunaliella tertiolecta cultured under batch and continuous culture conditions. We used complementary mass spectrometry methods for the determination and quantification of 14 arsenic species; an additional three species could be quantified but remained unidentified. Results The alga rapidly methylated the arsenate to dimethylarsinate (DMA), which then served as the precursor to arsenosugars and arsenolipids; the concentrations of these complex organoarsenicals increased throughout the experiments accompanied by a concomitant reduction in DMA concentrations. The pattern of compounds formed by the alga was similar for both batch and continuous cultures, but the concentrations were 2–3-fold higher in the continuous culture samples and the increases with time were much clearer. Discussion The data suggest that the arsenosugars and the arsenolipids were mostly formed simultaneously from DMA, although there was an indication that the arsenic phospholipids were at least partly also being formed from the arsenosugars. Overall, the data are consistent with a direct biosynthesis of DMA from arsenate by D. tertioleta, and thereafter a non-specific incorporation of DMA into commonly available alga metabolites encompassing various sugars and lipids.

Environmental context Knowledge of the fate of selenium in estuaries receiving inputs from coal-fired power stations is essential as these environments are important nursery habitats for marine life and selenium has been shown to cause fish and bird mortality and sublethal effects including oedema, chromosomal aberrations and reproductive success. Understanding selenium cycling allows risk assessment to be undertaken and appropriate action to protect resident organisms. Abstract The fate of selenium (Se) inputs from coal-fired power station operations in a marine dominated estuary, Lake Macquarie NSW, is explored, as well as Se toxicity, including sublethal and population effects. Selenium is rapidly adsorbed to sediments, and food webs are based on benthic food sources. Selenium is remobilised from sediments by volatilisation and diffusional processes following bioturbation. It is then transferred into food chains via benthic microalgae, deposit feeders and filter-feeding organisms processing suspended sediments. Historically, Se has been found to accumulate in fish to levels above those considered safe for human consumption. After the remediation of a major ash dam in 1995, Se inputs to Lake Macquarie have declined, and the Se concentrations of sediments have also reduced partially due to the deposition of cleaner sediment but also due to the formation of volatile dimethyl selenide. Bioturbation of oxidised surface sediments also results in the release of inorganic Se. In response to decreases in sediment Se concentrations, molluscs and fish Se concentrations have also reduced below deleterious levels, with most fish now being safe for human consumption. Selenium cycling involves the transformation of inorganic species (Se0, SeII, SeIV, SeVI) in sediments and the water column to dimethylselenide and dimethyl diselenide by bacteria with the accumulation of organic Se species in plant detritus (selenomethionine) and animals (selenomethionine and selenocysteine). Dissolved Se concentrations in Lake Macquarie, except near ash dam inputs, have always been well below those that cause toxicity. There is evidence based on Se sediment-spiking studies, however, that Se is probably causing sublethal effects. When undertaking risk assessments of Se, careful consideration should be given to understanding the fate of Se inputs and remobilisation into food webs as not all systems act in accordance with published studies that generally have high Se concentrations in the water column and phytoplankton-based food webs.

The Hawkesbury-Nepean River (HNR) is the largest catchment in the Sydney region and is undergoing unprecedented population growth. The HNR system receives a mix of anthropogenic inputs such as treated sewage, stormwater and agricultural runoff. Combined, these can diminish the ecological system health and pose potential concerns to human health. Of particular concern are inputs of untreated sewage, that can occur due to a range of different reasons including illegal point source discharges, failure of the sewerage network, and overloading of wastewater treatment plants during storm events. Here, we present findings of an intensive assessment across the HNR catchment where we used a weight-of-evidence (WOE) approach to identify untreated sewage contamination in surface waters against the background of treated effluent and diffuse inputs during post high flow conditions. Total nitrogen and phosphorus concentrations were used to assess treated effluent and diffuse inputs, and microbial analysis, including both culture-based traditional methods for E. coli and enterococci and qPCR analysis of Bacteroides and Lachnospiraceae, were used to assess raw sewage contamination. Despite a background of diffuse inputs from recent high flow events and the influence of treated wastewater, we found no gradient of faecal contamination along the HNR system or its tributaries. We observed two sites with evidence of untreated sewage contamination, where the human markers Bacteroides and Lachnospiraceae qPCR copy numbers were high. The biological and chemical approaches suggested these latter two hotspots originate from an industrial runoff source and possibly from a dry weather sewage leak. Our findings demonstrate the potential of a WOE approach in the assessment of human faecal signal in an urban river that can also pinpoint small sources of contamination as a strategy that can reshape the way monitoring is performed and the chemical end-points chosen to provide pertinent information on the potential risks to aquatic system health.

We conducted acute toxicity studies using semi-static protocols to examine the lethal responses of Australian bass and silver perch exposed to antimony (Sb) oxidation states in Sb(III) (10.5–30.5 mg L−1) and Sb(V) (95.9–258.7 mg L−1). Bioavailability and the effects of Sb on body ion regulation (Na, Ca, Mg, and K) were also investigated. Antimony species-specific effects were observed with exposure to both Sb oxidation states. Median lethal concentrations (LC50s) for Sb(III) were 13.6 and 18 mg L−1 for Australian bass and silver perch, respectively, and the LC50 for Sb(V) in Australian bass was 165.3 mg L−1. The LC50 could not be calculated for silver perch exposed to Sb(V) as the maximum exposure concentrations produced 40% mortality but a larger-than value of > 258.7 mg L−1 was estimated. Relative median potency values derived from the LC50s were 0.1 Sb(III) and 12.2 and 16.6 Sb(V) for Australian bass and silver perch, respectively, demonstrating greater toxicity of Sb(III) to both fish species. Antimony uptake in fish was observed. Median critical body residue (CBR50) values of 77.7 and 26.6 mg kg−1 for Sb(III) were estimated for Australian bass and silver perch, respectively, and 628.1 mg kg−1 for Sb(V) in Australian bass. Bioconcentration factors (BCFs) for both Sb(III) and Sb(V) did not change with exposure but the greater BCFs for fish exposed to Sb(III) indicate that it is more bioavailable than Sb(V) in acute exposure. No effects on whole-body Na, Ca, Mg, or K ions were observed with fish exposure to either Sb species.

A high proportion of populations in most developing countries live below the poverty line and those near refuse grounds resort to dumpsite farming to grow food. Consequently, high levels of waste-derived contaminants are found in crops consumed by these people. This study investigates the extent to which crops cultivated on the Mbale dumpsite (Uganda) were contaminated by 11 metals and 2 non-metals: iron (Fe), aluminum (Al), zinc (Zn), manganese (Mn), copper (Cu), mercury (Hg), lead (Pb), nickel (Ni), cobalt (Co), cadmium (Cd), selenium (Se), chromium (Cr), and arsenic (As). We investigated how element bioaccumulation in crops was influenced by the growth period (short-and long-term crop maturity). The short-term crops were Zea mays and Amaranthus cruentus, whereas the long-term crops were Manihot esculenta, Colocasia esculenta, Musa acuminata, Carica papaya, Coffea arabica, and Saccharum officinarum. Results showed that nine metals were present at concentrations above World Health Organization/Food and Agriculture Organization (WHO/FAO) food safety recommendations and hence may pose health risks to consumers. In this study, leaves contained higher metal concentrations than other analyzed consumable parts. Pb and Co were found at higher concentrations in leaves of short-term crops than in long-term crops. Among short-term crops, only Z. mays seeds contained permissible metal concentrations by WHO/FAO standards. The growth period was also found to influence metal bioaccumulation in crop types. Pb, Co, Fe, Al, and Cu concentrations were significantly higher in the short-term crops than in long-term crops, while Mn, Ni, and Cr concentrations were higher in long-term crops than in short-term crops. Overall, public awareness about the health risks associated with consuming short-term leafy crops grown on dumpsites should be improved to reduce toxic metal exposure. While implementing such a campaign, the food supply of individuals whose survival depends on such crops should not be jeopardized. Therefore, farmers need alternative farming areas outside dumpsites. (C) 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

•First pilot study on Sb genotoxicity in the circulatory erythrocytes of freshwater fish.•Sb(III) but not Sb(V) induced DNA damage in Silver perch under experimental conditions used.•Sb(III) alters the PCE/ NCE cytotoxicity index in Silver perch.•Both Sb(III) and Sb(V) show no genotoxic effect in micronucleus test.

The native freshwater gastropod Isidorella newcombi attacks the roots of developing rice plants in southern Australia and is controlled using copper sulphate. The apparent tolerance of this species to moderate levels of copper (Cu) exposure led us to investigate its potential usefulness as a biomonitor species. To assess its response to chronic Cu exposure, adult I. newcombi were exposed to 0–120 µg L−1 of Cu for 28 days. Lethal and sublethal responses were investigated. The relationships between subcellular biomarkers and life history traits also were explored. At exposure concentrations of 60 µg L−1 Cu and above, 100% mortality was observed during the 28-day exposure period. In these treatments, there was an exposure concentration dependent decrease in the time that the snails survived. In the surviving snails, there was an exposure concentration-dependent increase in tissue Cu concentration. In the snails exposed to Cu concentrations above 15 µg L−1, no eggs were produced during the final week of copper exposure, indicating that populations would not persist at Cu concentrations above 15 µg L−1. The general stress biomarker lysosomal membrane destabilisation (LD) indicated organisms exposed to 10 µg L−1 Cu and above were experiencing Cu induced stress. This suggests that LD could act as an early warning system for responses at higher levels of biological organisation in I. newcombi exposed to copper.

Food crops can be used as biomonitors to assess potential public health food safety hazards from contaminated agricultural environments. Globally, more than 800 million people grow fruits, vegetables, and grains on urban garden soils with unknown health risks. This worldwide practice has exposed consumers to pathogenic and carcinogenic risks from locally grown and imported contaminated foodstuffs such as Amaranthus cruentus and Zea mays, traditional and widely consumed crops across the globe. This study used Z. mays and A. cruentus crops to investigate the occurrence and spatial variations of aluminum (Al), chromium (Cr), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), mercury (Hg), and lead (Pb) concentrations across the Mbale dumpsite, Uganda. Mean concentrations for Fe, Al, Zn, Mn, and Cu were high in both crops, whereas Pb, Cr, Co, Cd, As, Hg, Se, and Ni occurred in trace amounts. Using the 2 crops as biomonitors, significant variations for Al, Zn, Fe, Cr, and Co concentrations in individual crops were identified across the dump center, hill slope, and riverbank. The variations in Al, Zn, Fe, Cr, and Co concentrations were specific for crop types, crop parts, and location. The highest overall accumulation of metals was at the dump center and in crop leaves. Except Pb concentrations in Z. mays seeds, Cr, Pb, Zn, and Al concentrations in other crop parts were above World Health Organization/Food and Agricultural Organization consumer food safety limits. Therefore, Z. mays and A. cruentus consumption could pose health risks to consumers. Further health assessments and potential regulations are recommended to reduce potential health risks from metals in crops for human consumption. Integr Environ Assess Manag 2020;16:362-377. © 2019 SETAC.

Food crops can be used as biomonitors to assess potential public health food safety hazards from contaminated agricultural environments. Globally, more than 800 million people grow fruits, vegetables, and grains on urban garden soils with unknown health risks. This worldwide practice has exposed consumers to pathogenic and carcinogenic risks from locally grown and imported contaminated foodstuffs such as Amaranthus cruentus and Zea mays, traditional and widely consumed crops across the globe. This study used Z. mays and A. cruentus crops to investigate the occurrence and spatial variations of aluminum (Al), chromium (Cr), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), mercury (Hg), and lead (Pb) concentrations across the Mbale dumpsite, Uganda. Mean concentrations for Fe, Al, Zn, Mn, and Cu were high in both crops, whereas Pb, Cr, Co, Cd, As, Hg, Se, and Ni occurred in trace amounts. Using the 2 crops as biomonitors, significant variations for Al, Zn, Fe, Cr, and Co concentrations in individual crops were identified across the dump center, hill slope, and riverbank. The variations in Al, Zn, Fe, Cr, and Co concentrations were specific for crop types, crop parts, and location. The highest overall accumulation of metals was at the dump center and in crop leaves. Except Pb concentrations in Z. mays seeds, Cr, Pb, Zn, and Al concentrations in other crop parts were above World Health Organization/Food and Agricultural Organization consumer food safety limits. Therefore, Z. mays and A. cruentus consumption could pose health risks to consumers. Further health assessments and potential regulations are recommended to reduce potential health risks from metals in crops for human consumption. Integr Environ Assess Manag 2020;16:362–377.