Waterborne Toxicity to Neotropical Invertebrates and Hazard of Cigarette Butt Leachates in Marine Environments.

Cigarette butts (CBs) are the most common type of beach litter worldwide and contain a complex mixture of chemicals. Given the recent interest in this emerging problem, it is important to assess the toxicity of CB leachates to a range of species from different regions, sensitivities, and ecological traits. We evaluated the waterborne toxicity of smoked CB to tropical invertebrates. Leachates were prepared in the laboratory and characterized for trace elements (Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb), ammonia nitrogen, and polycyclic aromatic hydrocarbons. Then a set of toxicity tests with marine invertebrates was performed as follows: the brine shrimp Artemia sp. (nontoxic); the amphipod Tiburonella viscana (median lethal concentration [LC50] of 0.038 CB/L); the tanaid Monokalliapseudes schubarti (LC50 of 0.126 CB/L); the copepods Tisbe biminiensis (median effect concentration [EC50] of 0.038 CB/L) and Nitokra sp. (EC50 of 0.009 CB/L); pluteus stage larvae of the sea urchin Echinometra lucunter (EC50 of 0.152 CB/L); the sand dollar Mellita quinquiesperforata (EC50 of 0.054 CB/L); and D-stage larvae of the mussel Perna perna (EC50 of 0.005 CB/L). The predicted no-effect concentration was estimated using species sensitivity distribution, producing a 5th percentile hazard concentration of 0.015 CB/L. This preliminary threshold allowed us to estimate the potential impact of a single CB to 67 L of seawater via leaching, contributing to the advancement of knowledge regarding the contamination, toxicity, and ecological risks of cigarette waste. Environ Toxicol Chem 2024;43:374-384. © 2023 SETAC.

Dealing with complex contamination scenarios: using a multi-geochemical approach to assess environmental quality and identify pollution sources in a semi-arid estuary from Brazil.

The Jundiaí-Potengi Estuary (EJP) is located on the semi-arid coast of northeastern Brazil and is influenced by multiple sources of contamination. The sediment quality of EJP was assessed by using a multi-geochemical approach during the dry and wet seasons. Sediments were analyzed for concentrations of nutrients, metals, polycyclic aromatic hydrocarbons (PAHs), pesticides, hormones (natural and synthetic), and sterols. The results were integrated by multivariate methods. The sediment was altered by the presence of contaminants from anthropogenic and natural sources. The middle and lower estuarine areas were considered more degraded in both seasons. In these regions, metals, hormones, sterols, and PAHs were found, indicating that these regions are severely affected by industrial, sanitary and aquaculture effluents, combustion of fossil fuels, and oil spills. The upstream region was contaminated by pesticides. The contamination pattern along the EJP shows the prevalence of local sources which continuously release the chemicals into the estuary. Worse conditions occurred during the rainy season, when the runoff from urban and rural areas is more intense and carries a greater load of contaminants to the EJP.

Can the toxicity of polyethylene microplastics and engineered nanoclays on flatfish (Solea senegalensis) be influenced by the presence of each other?

Microplastics and nanomaterials are applied in a myriad of commercial and industrial applications. When leaked to natural environments, such small particles might threaten living organisms' health, particularly when considering their potential combination that remains poorly investigated. This study investigated the physiological and biochemical effects of polyethylene (PE; 64-125 µm in size, 0.1, 1.0, and 10.0 mg·L-1) single and combined with an engineered nanomaterial applied in antifouling coatings, the copper-aluminium layered double hydroxides (Cu-Al LDH; 0.33, 1.0, and 3.33 mg·L-1) in the flatfish Solea senegalensis larvae (8 dph) after 3 h exposure, in a full factorial design. Particles ingestion, histopathology, and biochemical biomarkers were assessed. Fish larvae presented <1 PE particles in their gut, independently of their concentration in the medium. The histological health index showed minimal pathological alterations at PE combined exposure, with a higher value observed at 1 mg LDH·L-1 × 0.1 mg PE·L-1. Gut deformity and increased antioxidant defences (catalase), neurotransmission (acetylcholinesterase), and aerobic energy production (electron transport system) were observed at PE ≥ 1.0 mg·L-1. No oxidative damage (lipid peroxidation) or alterations in the detoxification capacity (glutathione-S-transferase) was observed on single and combined exposures. PE, combined or not with Cu-Al LDH, does not seem to compromise larvae's homeostasis considering levels reported so far in the marine and aquaculture environments. However, harsh effects are expected with MP contamination rise, as projections suggest.

Metal Bioaccumulation by the Neotropical Clam Anomalocardia flexuosa to Estimate the Quality of Estuarine Sediments.

This investigation evaluated the bioaccumulation potential of the tropical estuarine bivalve Anomalocardia flexuosa for trace metals. To this aim, chemical and sedimentological analyses and bioaccumulation tests were performed. The sediments were mainly composed by fine-sands and mud, with variable levels of organic matter and CaCO3. Muddy sediments from a depositional site (P2) presented the highest concentrations of metals, despite SEM/AVS not indicating bioavailability. Bioaccumulation factors showed high ratios for Cd, Ni, and Zn, while associations between the contents of mud, organic matter, CaCO3 and metals in sediments and tissues of A. flexuosa were indicated by a principal component analysis. The SEM/AVS was not effective to predict the bioavailability through dissolved metals. The results showed that contaminants were bioavailable, while the performed bioaccumulation test proved to be a reliable technique for assessing sediment contamination in estuarine regions. Moreover, A. flexuosa was considered an adequate test organism for bioaccumulation studies.

Impacts of dredging on biomarkers responses of caged bivalves in a semi-arid region (Ceará State, NE Brazil).

In this study, the performance of two native bivalves in responding to sediment resuspension was investigated during dredging operations of a semi-arid bay (Mucuripe, NE Brazil). The clam Anomalocardia flexuosa and the oyster Crassostrea rhizophorae were selected and caged in two sites influenced by the dredging plume. We assessed the bioaccumulation of metals and hydrocarbons in both species as biomarkers of exposure and then, biomarkers' responses were assessed in gills and digestive glands over a 28 days period, at 7 days intervals: the activities of phase I and II, and antioxidant enzymes, levels of lipid peroxidation and DNA strand breaks. Both transplanted bivalves accumulated Cu, polycyclic aromatic hydrocarbons (PAHs), and linear alkylbenzenes (LABs) in their whole-body tissues, whereas Ni, Pb and Zn accumulation was species-dependent. The exposure time set at day 28 was considered appropriate. Biomarkers exhibited time-related responses in both species, but gills exhibited a more sensitive response, indicating a function of barrier against the uptake of chemicals and also a relevant tissue to be targeted. In clams, Phase I and II enzymes (ethoxyresorufin O-deethylase and glutathione S-transferase) were induced during the period of intense dredging, while in oysters they were activated at the end of operations. Induction of antioxidant enzymes (glutathione peroxidase and glutathione reductase) and elevated levels DNA damage were observed in both exposure surveys. Clams and oysters were sensitive and responded to the exposure of resuspended sediments and the biomarkers of effects were associated with bioaccumulation of contaminants in the integrated analysis. These results indicate that The clam A. flexuosa and the oyster C. rhizophorae are suitable models to be used in monitoring programs or field exposure experiments in tropical regions.

Effects of mixtures of anticancer drugs in the benthic polychaete Nereis diversicolor.

The increasing consumption of anticancer drugs through single and/or combinatory chemotherapy worldwide raised concern regarding their toxicity burden in coastal zones. The toxicity of a mixture of three compounds involving the drugs cisplatin (CisPt), cyclophosphamide (CP) and tamoxifen (TAM) was determined on the marine polychaete Nereis diversicolor exposed to an increasing range of their concentrations, respectively: Mix A: 0.1 + 10 + 0.1 ng L-1; Mix B: 10 + 100 + 10 ng L-1; Mix C: 100 + 500 + 25 ng L-1; Mix D: 100 + 1000 + 100 ng L-1. Different endpoints were assessed, including disturbance in the burrowing behaviour, neurotoxicity (acetylcholinesterase - AChE activity), antioxidant enzymes (superoxide dismutase - SOD; catalase - CAT; selenium-dependent glutathione peroxidase - Se-GPx and total glutathione peroxidases T-GPx activities), biotransformation metabolism (glutathione-S-transferases - GST), lipid peroxidation (LPO) and genotoxicity (DNA damage). Biological effects of the mixtures of anticancer compounds on N. diversicolor were compared with previous studies about effects on the same biological model under single-drug exposure conducted with the same molecules. Regarding SOD activity, TAM showed an antagonist effect over CisPt and CP in mixtures C and D. In Mix D, there was a synergistic effect of TAM and CisPt that inhibited CAT activity and an additive interaction of CisPt and CP on the Phase II biotransformation enzyme. Drugs in Mix A also suppressed polychaetes' GST activity, although different from the respective single-drug responses, besides able to induce T-GPx activity, that was not sufficient to avoid oxidative damage and mid-grade DNA damage. Due to the absence of burrowing impairment in Mix A, mechanisms involved in neurotoxicity were other than the one driven by AChE alterations. At the intermediary concentrations (Mix B and C), only LPO occurred. Data from drugs individually may not predict the risks provided by mixtures.

Influence of anthropogenic activities and risk assessment on protected mangrove forest using traditional and emerging molecular markers (Ceará coast, northeastern Brazil).

Anthropogenic molecular markers were used to assess chemicals inputs and ecological risks associated from multiple sources to sediments in one of the largest tropical mangrove forests of South America, with a particular focus on lesser studied compounds resulting from rural activities. Total concentrations ranged from 23.4 to 228.2 ng g-1 for polycyclic aromatic hydrocarbons (∑PAHs), 750.4 to 5912.5 ng g-1 for aliphatic hydrocarbons (∑AHs), 32.4 to 696.6 ng g-1 for pesticides (∑pesticides), 23.1 to 2109.7 ng g-1 for coprostanol and sterols (∑sterols), 139.3 to 580.2 ng g-1 for naturals hormones (∑natural hormones) and 334.1 to 823.4 ng g-1 for synthetics hormones (∑synthetic hormones). The PAHs and AHs used as traditional anthropogenic markers showed a mixture between natural and anthropogenic sources, related mainly to inputs from higher plants, phytoplankton and both, biomass and petroleum combustion. Rural activities linked to agricultural pest control are the predominant source of pesticides, although minor inputs from pesticides used in urban public health campaigns and household activities were also detected. Synthetic hormones levels are two to three orders of magnitude greater than natural hormones levels and no correlations were observed between the main sewage markers and synthetic hormone concentrations, rural activities such as animal husbandry, which use drugs in management, may be the predominant anthropogenic sources of these compounds in the region. Traditional markers failed to detect ecological risks in rural areas, where synthetic substances (e.g. pesticides and hormones) are widely used and introduced in the environment.

Pollution status of marine protected areas worldwide and the consequent toxic effects are unknown.

Chemical pollution is considered a factor that may threaten marine protected areas (MPAs), and recent studies have found contamination and associated biological effects in some MPAs. However, organized data on this topic are lacking. This study reviewed the literature on pollution in MPAs in order to compile data, determine whether MPAs are influenced by pollution and, whenever possible, describe how they are being affected by contaminants. The results show that the pollution status is unknown in most MPAs worldwide. When any information is available, it is often insufficient to diagnose the threats to biodiversity or to support further actions. More robust and extensive information is available on a small number of MPAs, and much less information is available regarding the negative effects of pollution. More than 80% of the areas studied exhibited evidence of contamination at potentially toxic concentrations or were found to have a status that produced toxic effects on the biota. The scientific community is encouraged to study pollution in MPAs worldwide.

Multiresidue determination and predicted risk assessment of contaminants of emerging concern in marine sediments from the vicinities of submarine sewage outfalls.

Submarine sewage outfalls (SSOs) are considered the main input source of contaminants of emerging concern continuously released in coastal areas, with the potential to cause adverse effects for aquatic organisms. This work presents the investigation of nine endocrine disrupting chemicals (EDCs) and 26 pharmaceutically active chemicals (PhACs) in marine sediments within the vicinities of 7 SSOs along the São Paulo State Coast (Brazil). Method optimization for the multi-residue determination by GC-MS/MS and LC-MS/MS using QuEChERS extraction/clean-up are discussed. Results demonstrate the occurrence of EDCs in concentrations ranging from less than method quantification limits (MQL) to 72.5 ng g-1 in sediments. All PhACs were

Continuous Exposure to Microplastics Does Not Cause Physiological Effects in the Cultivated Mussel Perna perna.

The environmental impact of microplastics is a challenging theme, especially under realistic experimental conditions. We investigated physiological responses to 0.1-1.0 µm PVC particles intake by the mussel Perna perna after a relative long-term exposure (90 days) at a less extreme concentration compared with previous studies (0.125 g/L). Microplastic intake was inferred by the presence of PVC in the feces of mussels, and physiological damages were assessed through ingestion rate, assimilation efficiency, growth rate, cellular and molecular biomarkers (lysosomal integrity, lipid peroxidation, and DNA damage), and condition index. All physiological responses showed nonsignificant effects of the microplastics on the exposed mussels. We suggest that, despite the experimental concentration of microplastics, mussels were able to acclimate to the exposure through their abilities for long-term recovery and tolerance to stresses. These data have positive implications for environmental health and in terms of human food resource because mussel farming is a worldwide practice that heavily relies on plastic materials, increasing the chances of microplastic exposure and mussels contamination.

Integrative assessment of sediment quality in lower basin affected by former mining in Brazil.

The Ribeira de Iguape River (Southeast Brazil) is metal contaminated by mining activities. Despite it has been cataloged as "in via of restoration" by the literature, this basin is still a sink of pollution in some segments of the fluvial system. This study aimed to assess the sediment quality in the lower part of the RIR basin. The employed approach was based on biological responses of the freshwater clam Corbicula fluminea after 7-day exposure bioassays using as the reference site the Perequê Ecological Park. Toxic responses (burial activity and lethality) and biochemical biomarkers (GST, GR, GPx, LPO, MTs, AChE and DNA damage) were evaluated and then integrated with metal bioavailability and chemical concentrations to address the sediment quality in the area through the weight-of-evidence approach. A multivariate analysis identified linkages between biological responses and contamination. Results pointed that, despite being below the benchmarks of the US Environmental Protection Agency, there is slight metal contamination in the lower part of the basin which induces oxidative stress in C. fluminea; other toxic responses were sometimes attributed to As and Cr bioaccumulation. The sediment quality values (TEL-PEL values in mg/kg) were calculated for the current study for As (0.63-1.31), Cr (3.5-11.05), Cs (1.0-1.17), Cu (6.32-7.32), Ni (6.78-7.46), Ti (42.0-215), V (1.77-8.00). By comparison with other international guidelines, the sediment quality of the lower basin of the Vale de Ribeira does not identify a significant environmental risk.

Gladius and its derivatives as potential biosorbents for marine diesel oil.

The demand for low cost and effective materials to remove contaminants such as residues of oil spills has encouraged studies on new biosorbents produced from wastes. Considering the overgeneration of fishing residues and the necessity to provide an alternative purpose for such materials, this study aimed to evaluate squid gladius and its derivatives (ß-chitin and chitosan) as sorbents to remove marine diesel oil (MDO) from fresh and artificial seawater. It was also executed an attempted to improve their performances through a high-intensity ultrasound treatment (UT-gladius and UT-ß-chitin). All sorbents removed MDO at both salinities. Contact surface area, salinity, and water retention seemed to play a key role in the outcomes. UT-ß-chitin's performance was significantly superior to ß-chitin's and chitosan's in MDO removal at salinity 0, as well as at salinity 30, where gladius and UT-gladius also excelled. Ultrasound treatment improved the oil removal performance of UT-ß-chitin by increasing its contact surface area. This is the first report on the efficiency of gladius and UT-ß-chitin for such purpose, and brought up huge possibilities and new questions that can lead to the achievement of biosorbents of great efficiency.

Sediment quality in a metal-contaminated tropical bay assessed with a multiple lines of evidence approach.

A sediment quality assessment was performed near to the main industrial source of metal contamination in Sepetiba Bay, Brazil, which represents one of the worst cases of trace metal contamination reported for coastal areas. Acute and chronic toxicity tests, benthic fauna community analysis and metal bioavailability evaluations were applied to identify risks to the benthic community. Significant amphipod mortality was observed close to the major pollution source and lower copepod fertility was observed for all stations. Equilibrium-partitioning and biotic-ligand models to predict pore water metal toxicity, which were based on acid-volatile sulfide (AVS) and organic carbon fraction (fOC) normalization approaches, suggested that metals are not likely to be available in sediment pore water. However, Cd, Pb and Zn concentrations were mainly (>50%) weakly bound to sediments, suggesting high potential bioavailability. Linking the chemical results with ecotoxicological responses, we observed that sediment-feeding organisms presented acute and chronic toxicities that were positively correlated to the metal concentrations in the sediments. Additionally, benthic fauna composition was dominated by tolerant species, revealing a trophic structure response to environmental contamination. These results reinforce the necessity of a multiple lines of evidence approach to establish sediment quality and to support environmental management decisions that are based on observed effects and potential extrapolation scenarios into the future.

Metal contamination and fractionation in sediments from the lower basin of the Vale do Ribeira (SE, Brazil).

The sediment quality of Ribeira de Iguape River is affected by former Pb extraction mining. Some studies affirm the restoration status of the basin, however, mobility of metals and its associated risk is still questioned. This study integrates the metal concentrations in the lower part of the basin with different contamination source to determine the existence of risks associated with the mobile fractions of the geochemical matrix. Despite concentrations of metals were low and the environmental risk factor values were negative, our results indicated that As, Mn, Pb, and V were present in the most labile forms. The multivariate analysis conducted using metal concentrations, environmental risk factor values and speciation suggested that any risk would be associated with the labile fractions of the analyzed elements, especially for Pb. The station from Registro was stressed by Co, Pb and Zn; with Pb under the reactive fraction that could be associated with high mobility and potential bioavailability.

Bioaccumulation kinetics of copper in Ruditapes philippinarum exposed to increasing, continuous and pulsed exposure: Implications for growth.

Metal bioaccumulation and toxicity to aquatic organisms depends on factors such as magnitude, duration and frequency of the exposure. The type of the exposure affects the toxicokinetic processes in the organisms. In this study, we carried out 30-day toxicity tests on juveniles of Ruditapes philippinarum exposed to increasing, continuous and pulsed exposure. Organisms were exposed to copper-spiked sediments followed by a 10-day recovery period. We assessed the interaction between the kinetics of subcellular copper partitioning and the growth response. Results showed that the growth rate of the bivalve was inversely correlated to the bioaccumulation rate and that sublethal copper concentrations stimulated the detoxification mechanisms inside the organism regardless the type of the exposure. However, a large stimulatory effect on growth was observed during the recovery period, associated with significant negative accumulation rate values and dependent on the type of antecedent exposure. This suggested that on individual and short-term basis pulsed exposures have a more adverse effect compared to increasing or continuous exposure scenarios.

Effects of harbor activities on sediment quality in a semi-arid region in Brazil.

Tropical marine environments are rich in biodiversity and the presence of harbor activities in these areas can harm the coastal ecosystems. In this study, we assessed sediment quality of two harbors from a tropical region in Brazil by applying multiple lines-of-evidence approach. This approach included the integration of results on: (1) grain size, organic matter, organic carbon, nitrogen, phosphorus, trace metals, polycyclic aromatic hydrocarbons, linear alkylbenzenes, and tributyltin; (2) acute toxicity of whole sediments and chronic toxicity of liquid phases; and (3) benthic community descriptors. Our results revealed that the main contaminants detected in sediments from Mucuripe and Pecém Harbors were chromium, copper, nitrogen, zinc, and tributyltin. These toxicants arise from typical harbor activities. However, the changes in benthic composition and structure appear to depend on a combination of physical impacts, such as the deposition of fine sediments and the toxic potential of contaminants, especially in Mucuripe. Thus, apart from toxicants physical processes are important in describing risks. This information may assist in management and conservation of marine coastal areas.

Multiple Biomarker Responses in Corbicula fluminea Exposed to Copper in Laboratory Toxicity Tests.

This study evaluated the alteration of the enzymatic system of the freshwater Asian clam exposed to different copper concentrations. Individuals of Corbicula fluminea were exposed to different concentrations of dissolved Cu (0.5, 1, and 2 mg L(-1)) for 7 days, then, biomarkers of oxidative stress (GST, GPx, GR), exposure (MTs), effect (AChE), and damage (LPO, DNA strand breaks) were quantified. Results showed positive correlations between dissolved metal concentrations and GPx, MTs, and DNA damage, and negative correlation with GST and AChE. In contrast, no clear trend was found for GR and LPO. In general, the established mechanisms of protection might have a beneficial effect on the decreasing ROS attack on membrane and the activation of the metallothioneins. Integrated biomarker analysis revealed that the measured alterations are well correlated with the levels of increasing dissolved copper concentrations in water, demonstrating the effectiveness of this organism for biomonitoring approach purposes.

Spatial variability in persistent organic pollutants and polycyclic aromatic hydrocarbons found in beach-stranded pellets along the coast of the state of São Paulo, southeastern Brazil.

High spatial variability in polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, such as DDTs, and polybrominated diphenylethers was observed in plastic pellets collected randomly from 41 beaches (15 cities) in 2010 from the coast of state of São Paulo, southeastern Brazil. The highest concentrations ranged, in ng g(-1), from 192 to 13,708, 3.41 to 7554 and <0.11 to 840 for PAHs, PCBs and DDTs, respectively. Similar distribution pattern was presented, with lower concentrations on the relatively less urbanized and industrialized southern coast, and the highest values in the central portion of the coastline, which is affected by both waste disposal and large port and industrial complex. Additional samples were collected in this central area and PCB concentrations, in ngg(-)(1), were much higher in 2012 (1569 to 10,504) than in 2009/2010 (173 to 309) and 2014 (411), which is likely related to leakages of the PCB commercial mixture.

Using an integrated approach to assess the sediment quality of an estuary from the semi-arid coast of Brazil.

The Jundiaí-Potengi Estuary (JPE) on the semi-arid coast of Brazil is influenced by multiple sources of pollution. Sediment quality at 10 JPE sites was evaluated through an integrated approach. Rainy and dry seasons were considered. Collected sediments were analyzed for texture, metal, nitrogen, phosphorus concentrations, and toxicity to invertebrates. Geochemical and ecotoxicological data were integrated using qualitative approaches and multivariate techniques. We observed decreased sediment quality in both seasons, particularly in the mid-estuary. In the dry season, the contamination-toxicity relationship was clearer, as hydrological conditions favor contaminant retention within the estuary. Rainy season conditions were found to be worse, since stormwater drainage from agricultural and urban areas carries the contamination into the estuary. Because of the contamination sources and dissolved and particle-bound metal transport, contamination and toxicity did not correlate as clearly in the rainy season. The results suggest that unmeasured contaminants are contributing to JPE sediment degradation.

A critical comparison of different approaches to sediment-quality assessments in the Santos Estuarine System in Brazil.

This study focuses on the discussion of different lines of evidence (LoEs) applied to a sediment-quality assessment that considered the following: chemical concentrations of metals; polycyclic aromatic hydrocarbons (PAHs) in estuarine waters, sediments, and oysters (native and caged Crassostrea brasiliana); PAHs in semipermeable membrane devices (SPMDs); simultaneously extracted metals-acid volatile sulfides (SEM-AVS); benthic community assessment (the exploratory benthic index and the relative benthic index); chronic toxicity tests with the sea urchin Lytechinus variegatus; and bioaccumulation models. Significantly contaminated sediments from the Santos Estuarine System and the consequent toxicity of tested organisms were measured. Caged oysters presented bioaccumulation rates ≤2,500% of total PAH content and 200% of metal content when compared with control organisms from an uncontaminated area. SPMD results presented the same bioaccumulation pattern as caged oysters but at lower concentrations. Benthic communities presented some alterations, and there was a predominance of tolerant species in the inner part of the estuary. According to the SEM-AVS approach, metals should be assumed to be nonbioavailable, but experiments with transplanted C. brasiliana showed metal bioaccumulation, particularly in the cases of chromium, copper, mercury, and zinc. The weight-of-evidence approach was applied to compare and harmonize LoEs commonly used in sediment-quality assessments and to then classify estuary environments according to both their potential for having adverse effects on the biota and their possible ecological risks. All of the results of these approaches (except for SEM-AVS) were found to complement each other.