Temporal variation of mercury levels in fish, soil, and sediments in an Amazon reservoir: insights from 35 years of river impoundment in Pará State, Brazil.

The increase of mercury (Hg) concentrations in abiotic and biotic compartments of aquatic ecosystems following the river impoundment for building a hydroelectric reservoir is one of many environmental and social impacts that the construction of hydroelectric plants can trigger. Yet, long-term studies in Amazon reservoirs are still scarce. The present study aimed to understand the effects of dam impoundment in THg concentrations in an Amazon reservoir up to 35 years of its creation.

First assessment of persistent organic pollutants and halogenated natural compounds in an omnivorous resident coral-reef fish species, black triggerfish, Melichthys niger, from an Atlantic oceanic island, Brazil.

Studies on the occurrence of POPs and other persistent compounds in pristine areas are extremely valuable, as they offer insights on the long-range transportation of POPs and the occurrence of natural compound producers' areas. In this regard, this study aimed to report data of both anthropogenic (polychlorinated biphenyls, PCBs, and polybrominated diphenyl ethers, PBDEs) and natural (methoxylated PBDEs, MeO-BDEs) compounds in tissues of the black triggerfish, Melichthys niger (Tetraodontiformes, Balistidae), specimens (n = 30) sampled in 2018 during a scientific expedition conducted at Trindade Island. Concentrations of ∑PCBs ranged from 73 to 1052 ng g lw in liver, 334 to 1981 ng g lw in gonads, and 20 to 257 ng g lw in muscle, with the predominance of PCB-180 in liver and PCB-52 in gonad and muscle.

Mercury concentrations and differences in isotopic niches of fish from upstream and downstream of an Amazon reservoir dam.

Reservoir construction promotes many environmental impacts, including the enhancement of mercury concentrations in fish. The processes that can influence mercury concentrations in fish in Amazonian reservoirs are still little explored in depth, especially when we consider the possible particularities of the ecosystems in question. This study aims to investigate how mercury concentrations in fish could be influenced by the Tucuruí dam, considering possible changes in their feeding and trophic position according to the dam position (up or downstream).

A multi-biomarker approach to verify chronic effects on Eisenia andrei earthworms exposed to tailings from one of the world's largest mining disasters.

Mining is of great relevance to the global economy, but its activities are challenging due to socio-environmental impacts. In January 2019, an iron ore tailings dam collapsed in Brumadinho (Minas Gerais, Brazil) releasing 12 × 10 m of tailings, causing human losses and devastation around 3.13 × 10 m of a watershed.

Brominated flame retardants and natural organobrominated compounds in a vulnerable delphinid species along the Brazilian coast.

Guiana dolphins, Sotalia guianensis, are vulnerable to extinction along their distribution on the Brazilian coast and assessing chemical pollution is of utmost importance for their conservation. For this study, 51 carcasses of Guiana dolphins were sampled across the Brazilian coast to investigate legacy and emerging brominated flame retardants (BFRs) as well as the naturally-produced MeO-BDEs. PBDEs and MeO-BDEs were detected in all samples analyzed, whereas emerging BFRs were detected in 16 % of the samples, all in Rio de Janeiro state.

Trophic dynamics of methylmercury and trace elements in a remote Amazonian Lake.

Information on pollutant trophodynamics can be crucial for public health, as contaminated food consumption may lead to deleterious effects. This study was performed in Puruzinho Lake, a remote body of water in the Brazilian Amazon from which a riparian human population obtains an important part of its animal protein intake. Samples from 92 individuals, comprising 13 species and four trophic guilds (iliophagous, planktivorous, omnivorous, and piscivorous fish) were analysed for the determination of trace elements (Fe, Cr, Mn, Ni, Zn, Ca, Sr, Cd, Sn, Tl and Pb) and methylmercury concentrations.

First assessment of atmospheric pollution by trace elements and particulate matter after a severe collapse of a tailings dam, Minas Gerais, Brazil: An insight into biomonitoring with Tillandsia usneoides and a public health dataset.

In this study, samples of bromeliad Tillandsia usneoides (n = 70) were transplanted and exposed for 15 and 45 days in 35 outdoor residential areas in Brumadinho (Minas Gerais state, Brazil) after one of the most severe mining dam collapses in the world. Trace elements aluminum (Al), arsenic (As), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), manganese (Mn), nickel (Ni) and zinc (Zn) were quantified by atomic absorption spectrometry. Scanning electron microscope generated surface images of T.

Evaluating total mercury and methylmercury biomagnification using stable isotopes of carbon and nitrogen in fish from the Madeira River basin, Brazilian Amazon.

The isotopic signatures of carbon in primary consumer fish species in the Madeira River basin (Western Amazon) follow a pattern, with basal species feeding mainly on C (e.g., vascular plants and phytoplankton).

Mercury methylation upon coastal sediment resuspension: a worst-case approach under dark conditions.

Mercury behavior upon resuspension of sediments from two impacted areas of Guanabara Bay was evaluated to assess worst-case methylmercury (MeHg) responses, under dark experimental conditions to prevent demethylation by photolysis. Study areas include the Rio de Janeiro Harbor (RJH) and the chlor-alkali plant-affected Meriti River (MR) estuary. Total mercury (THg) and MeHg concentrations were determined along 24-h experiments of sediment resuspension in the bay water in dark conditions.

Flood-pulse and trophic position modulate mercury concentrations in fishes from an Amazon floodplain lake.

Mercury (Hg) bioaccumulation can be influenced by biological characteristics (e.g., trophic position) and environmental changes (e.

Ventral feathers contained the highest mercury level in brown booby (Sula leucogaster), a pantropical seabird species.

Seabirds are extensively used as environmental biomonitors and feathers are among the most analyzed matrices because they are one of the main excretory pathways to detoxify the bird's body of environmental contaminants. Still, there is a variation in contamination level between the different feathers of seabird species, driven by diet and physiology, such as molt strategy and feather formation sequence. We measured total mercury (THg) concentration in different types of feathers (wing, tail, ventral and dorsal) of the same individual in adults and juveniles of brown boobies (Sula leucogaster) from the northern coast of Rio de Janeiro state, Brazil.

Trophodynamics of trace elements in marine organisms from cold and remote regions of southern hemisphere.

Trace metals bioaccumulate in aquatic organisms and some of them biomagnify through food webs, posing a threat to the organisms or their human consumers. Although the trophodynamics of many trace metals is well known in the northern hemisphere, much less is known about metals in aquatic food webs from cold and remote coastal zones of the southern hemisphere. To fill this gap, we investigated the trophodynamics of Al, Co, Cr, Li, Mo, Ni, Sr, and V, which were measured in marine macroinvertebrates and fishes from inshore and offshore locations in each of the Chilean Patagonia and the Antarctic Peninsula area.

Trophic position, altitudinal distribution, and water dependence as determining factors for mercury concentrations in tropical montane anurans.

Mercury (Hg) is a widespread and toxic contaminant with potential for long-range atmospheric transport. Previous work has shown that temperate and subtropical montane ecosystems have great potential for deposition of this element. However, little information exists regarding Hg dynamics in tropical mountains.

A review on pesticides in flower production: A push to reduce human exposure and environmental contamination.

In several countries, flower import regulations are restricted to food security, by establishing maximum residue limits (MRL) for pesticides in flower-based food products and biosafety, in order to limit the circulation of vectors, pests and exotic species across borders. In this context, the lack of limits on pesticides in flower-products for ornamental purposes can influence the pesticide overuse in production areas, as well as the transfer of contaminated products between countries. Therefore, the purpose of this review was to discuss possible adverse effects on human and environmental health of pesticides used in floriculture, evaluating regulations on the use of these pesticides in the main importing and flower-producing countries.

Bioaccumulation of mercury is equal between sexes but different by age in seabird (Sula leucogaster) population from southeast coast of Brazil.

Since several seabird species have sexual size dimorphism, in which one sex is larger than the other, and may consume bigger prey, this size difference may affect the contamination concentration in the seabird's tissues depending on their sex and age. In this study, mercury contamination was investigated in brown booby (Sula leucogaster) adults and juveniles during their breeding season at the Santana Archipelago, on the southeast coast of Brazil. Two hypotheses were evaluated: 1.

Mercury Concentrations in Four Marine Fishery Resources from Rio de Janeiro Coast, SW Atlantic, and Potential Human Health Risk Via Fish Consumption.

Mercury (Hg) contamination has caused ecological and socioeconomic problems worldwide. One of the main Hg contamination routes by the human populations is through fish ingestion. Herein, we analyzed the total Hg concentrations (THg) in highly consumed marine fish species: Brazilian flathead Percophis brasiliensis, Atlantic bigeye Priacanthus arenatus, Stripped weakfish Cynoscion guatucupa, and Jamaica weakfish C.

Bacterial diversity changes in agricultural soils influenced by poultry litter fertilization.

Poultry litter is widely applied as agricultural fertilizer and can affect the soil microbiome through nutrient overload and antibiotic contamination. In this study, we assessed changes in soil bacterial diversity using high-throughput sequencing approaches. Four samples in triplicate were studied: soils with short- and long-term fertilization by poultry litter (S1 = 10 months and S2 = 30 years, respectively), a soil inside a poultry shed (S3), and a forest soil used as control (S0).

Persistence, bioaccumulation and vertical transfer of pollutants in long-finned pilot whales stranded in Chilean Patagonia.

Long-finned pilot whales (LFPW) are cetaceans with strong social groups often involved in mass strandings worldwide. However, these beachings occur for reasons that are not fully understood. In 2016, 124 LFPW were stranded on the Chilean Patagonian islands, offering a unique opportunity to obtain crucial information on the ecology, biology, and genetics of this population.

Changes in mercury distribution and its body burden in delphinids affected by a morbillivirus infection: Evidences of methylmercury intoxication in Guiana dolphin.

An unusual mortality event (UME) attributed to morbillivirus infection was identified in two Guiana dolphin populations from the Southeastern Brazilian coast. The aim of this study was to characterize total mercury (THg), methylmercury (MeHg) and selenium (Se) bioaccumulation and body burden in Guiana dolphins from Sepetiba Bay (RJ) collected before (n = 61) and during the UME (n = 20). Significantly lower Se concentrations were found in the livers of individuals collected during the UME (Mann-Whitney test; p = 0.

First year after the Brumadinho tailings' dam collapse: Spatial and seasonal variation of trace elements in sediments, fishes and macrophytes from the Paraopeba River, Brazil.

On January 2019, the B1 iron ore tailings' dam collapsed in Brumadinho, Brazil, being one of the worst mining-related disasters, with 270 human deaths (11 of them still missing) and 12.10 m of tailings released to the environment. The tailings devastated the Córrego do Feijão brook and reached the adjacent Paraopeba River, the region's main watercourse and a major tributary of the São Francisco basin.

An upwelling area as a hot spot for mercury biomonitoring in a climate change scenario: A case study with large demersal fishes from Southeast Atlantic (SE-Brazil).

Data concerning the monomethylmercury (MeHg) bioaccumulation in marine biota from Southeast Atlantic Ocean are scarce. This study purchased large specimens of demersal fishes from an upwelling region: Warsaw grouper (Epinephelus nigritus), Dusky grouper (Epinephelus marginatus) and Namorado sandperch (Pseudopercis numida). The authors addressed the bioaccumulation and toxicokinetic of mercury in fish organs, and the toxicological risk for human consumption of this metal in the muscle tissues accessed.

Biomonitoring mercury contamination using fur from roadkilled giant anteaters.

The giant anteater (Myrmecophaga tridactyla) can occur in both preserved and anthropogenic environments in Brazilian biomes. The Cerrado biome, where the samples were collected, is considered one of the world's biodiversity hotspots; however, a large part of it has been converted to pasture and agricultural land. In this environment, animals may be exposed to contaminants, such as mercury (Hg).

Dynamics of Hg and MeHg in the Madeira River basin (Western Amazon) before and after impoundment of a run-of-river hydroelectric dam.

The impact of a hydroelectric run-of-river (RoR) dam construction on the dynamics of total mercury (THg) and methylmercury (MeHg) is of interest to the environment and health of human and wild life. We monitored (May 2010 to October 2018) THg and MeHg in the waters and in the suspended particulate matter (SPM) of the Madeira River and its tributaries (before and after dam construction) to evaluate changes upstream and downstream from the Santo Antonio Hydroelectric Dam (SAHD). We collected 2826 samples of water and SPM at sampling stations upstream (UPMD-01, UPMD-02 and UPMD-03) and downstream the Madeira River (DWMD-04, DWMD-05 and DWMD-06), and Tributaries upstream (Branco River, Jaci-Parana River, Jatuarana-I Igarapé, Contra River, Caripunas Igarapé, Ceara Igarapé, and Teotonio Igarapé) and downstream (Jatuarana-II Igarapé and Belmont Igarapé) from the SAHD and monitored water and the total load of SPM.

Fluoroquinolone-contaminated poultry litter strongly affects earthworms as verified through lethal and sub-lethal evaluations.

Poultry litter is one of the main sources of fluoroquinolones (FQs) in agricultural soils. In this study, our main goal was to investigate FQ-contaminated poultry litter effects on Eisenia andrei earthworms. To achieve this, acute and chronic tests covered several endpoints, such as avoidance, biomass, lethality, reproduction and changes to immune cells.