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This study examines the water quality in the Yaqui Valley in Mexico, a semi-arid region impacted by mining, agriculture, and aquaculture. Contamination sources, health risks and ecological impacts are investigated. Freshwater was found to be contaminated by dissolved As, presumed to result from mining activities in the mountains. Drainage water revealed an overall contamination by dissolved As and by suspended particles enriched with Al, Fe and Mn, associated with runoff processes. Intermittent contamination of drainage water by Cu, K + , NO 3 - and PO 4 3- is attributed to the use of fertilizers or pesticides. In the coastal area, drainage water contains high concentrations of Na, Ca, SO 4 2- and Cl, related to salinization processes, as well as higher concentrations of dissolved As, related to solid/liquid interactions that are enhanced by salinization. This drainage water discharges into the bay, degrading the seawater quality and increasing ecological risks. Outputs of this study can serve as a reference for the protection of this economically important coastal ecosystem. Concerning health risks, this study demonstrates that groundwater is also contaminated by dissolved As, believed to be associated with transfers from the geological basement to the dissolved phase of water, and other major chemicals related to salinization processes. The findings indicate that ingesting the groundwater poses a significant risk to human health with a primary exposure risk associated with dissolved As, particularly among children. This study presents crucial data for the Yaqui population, water managers and researchers, and provides novel insights into the management and mitigation of the identified risks., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Barats reports financial support was provided by National Research Agency (ANR). Gonzalez-Perez reports financial support was provided by Consejo Nacional de Ciencia y Tecnología (CONACYT). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

This study focuses on the "El Lavadero" tailings deposit, a mining environmental liability (MEL) located near the town of San Felipe de Jesús, Sonora, in northwest Mexico. The objective was to determine the total arsenic (As) content, its granulometric and geochemical distribution, as well as its mobilization capacity and bioavailability. The results from oxidized and unoxidized tailings showed low potential of hydrogen (pH) values (2.4-5.7) and high concentrations of total arsenic (8235-36,004 mg kg -1 ), predominantly in the finer granulometric fractions (< 0.05 mm). Arsenic also prevails in the finest fraction of agricultural soil (> 2 mm). These fine particles could present adverse environmental effects due to their potential to be transported by leaching and water suspension. In contrast, arsenic in the effluent sediments is primarily found in the coarser fraction (> 2 mm). A significant proportion of arsenic in the tailings (5-40%) was found in the non-residual geochemical fractions (I + II + III) (1106-7675 mg kg -1 ), indicating potential for mobilization and bioavailability. Depending on environmental conditions (redox potential and pH), arsenic can redissolve and exhibit high mobility in abiotic media, which may ultimately impact the environment and human health. Therefore, it is crucial to rehabilitate the "El Lavadero" MEL to prevent further environmental damage. This study provides useful information to understand some phenomena in other global mining environmental liabilities, such as mobilization and bioavailability of arsenic and its possible impact on the surrounding environment and biota, contributing to the worldwide research of ecosystems polluted by mining activity, especially in arid and semi-arid climates., Competing Interests: Declarations. Competing Interests: The authors have no relevant financial or non-financial interests to declare., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Aquatic ecosystems have been suffering deleterious effects due to the development of different economic activities. Metal(loid)s are one of the most persistent chemicals in environmental reservoirs, and may produce adverse effects on different organisms. Since fishes have been largely used in studies of metal(loid)s exposure, tilapia and largemouth bass were collected in three ecosystems from the Yaqui River Basin to measure the concentrations of metal(loid)s (chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), zinc (Zn) arsenic (As), mercury (Hg), and selenium (Se)) and some biomarkers (somatic indices, metallothionein expression and histopathological analysis) in tissues of both species. Metal(loid) concentrations varied seasonally among ecosystems in tissues of both species. The elements varied seasonally and spatially in tissues of both species, with a general distribution of liver > gills > gonads. Also, biomarkers showed variations indicative that the fish species were exposed to different environmental stressor conditions. The highest values of some biomarkers were in largemouth bass, possibly due to differences in their biological characteristics, mainly feeding habits. The multivariate analysis showed positive associations between metal(loid)s and biomarkers, which are usually associated to the use of these elements in metabolic and/or regulatory physiological processes. Both fish species presented histological damage at different levels, from SI types (changes that are reversible for organ structure) to SII types (changes that are more severe but may be repairable). Taken together, the results from this study suggest that the Yaqui River Basin is moderately impacted by metals and metalloids., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Our understanding of the trophic transfer of pollutants in marine subtropical ecosystems remains limited due to the complexity of their food webs. Thus, we aimed to evaluate Cd, Cu, Mn, Pb, and Zn sources, incorporation, and trophodynamics throughout the food web of the southeastern Gulf of California by stomach content analysis, stable isotope analysis, isotope mixing models, and trace element analysis in biological and environmental matrices. The food web comprised three main trophic guilds (TG1, TG2, and TG3). The bioaccumulation of Cd and Zn from seawater was efficient (> 1000) in TG2 and TG3. Bioaccumulation factor from sediment (BSAF >1) evidenced of Cd in all trophic guilds. In addition, non-trophic Cd relationships were identified in the food web. Based on the trophic magnification factor (TMF), Mn and Pb showed biodilution (TMF Mn  = 0.38; TMF Pb  = 0.16), while Cu and Zn exhibited biomagnification (TMF Cu  = 2.08; TMF Zn  = 3.31)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The biomagnification of Hg and Se was studied using nitrogen stable isotope analysis during four seasons in a coastal lagoon of the eastern central Gulf of California. This lagoon receives agricultural, municipal, and shrimp aquaculture effluents. The species were categorized into organism groups and presented a significant accumulation of Hg and Se with respect to the sources, while the concentration of both elements in sediment and suspended particulate matter (SPM) was low. Our data confirms the positive transfers (biomagnification factors >1) of Hg and Se in the entire studied food web, and it was structured in five trophic levels across all seasons. Additionally, there were no linear correlations between the molar Se:Hg ratios and the trophic levels of the organism groups. However, the Se:Hg ratios among organism groups were >1, which indicates that there is an excess of Se and that it is not a limiting factor for the detoxification of Hg., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In the present paper, we investigated the accumulation of six metals in tilapia (Oreochromis nilocticus) and largemouth bass (Micropterus salmoides) as indicators of the environmental pollution present at three constructed dams in the Yaqui River basin in Sonora, Mexico. The La Angostura (ANG), El Cajon de Onapa (ECO), and El Oviachic (OVI) dams are ecosystems under different degrees of anthropogenic stress. The collected fishes were dissected to obtain liver, gonad, stomach, gill, and muscle samples to determine the metal concentrations of Fe, Mn, Ni, Cu, Zn, and Cr. The results of a PERMANOVA showed that the concentrations of Fe, Cu, and Zn were significantly higher in tilapia liver, stomach, and gill tissues compared with those of the largemouth bass. Also, differences were detected between seasons, with the metal concentrations during the dry season being significantly higher than those of the rainy season (p < 0.001). The results of a principal component analysis showed an association between metals, tissues, and dams with significantly higher (p < 0.001) concentrations in tilapia from the ECO dam compared with those from the ANG and OVI dams. The general distribution of metals in the tissues was as follows: liver > stomach-gills > gonads > muscle. Variations in metal concentrations may be indicative of the different sources of anthropogenic stress in each ecosystem.

Marine ecosystems are subject to contamination by metals and metalloids and other elements and compounds that are emitted due to various human activities. These substances subsequently induce changes in marine biota after entering the marine environment. Marine organisms are frequently consumed worldwide because they constitute relatively cheap and accessible food items of high nutrient quality. The aim of this study was to estimate metal accumulation in frequently consumed marine species and to evaluate the associated health risks for particular population groups in a coastal region of northwestern Mexico. The marine species were consumed in different quantities between spring (from 0.29 kg year -1 for white clam, to 38.40 kg year -1 for blue crab) and autumn (from 0.34 kg year -1 for white clam, to 15.02 kg year -1 for leopard grouper). The general distribution of metal concentrations in the marine species (n = 13 in each season) evaluated in this study followed the trend of Fe > Zn > Cu > Mn > Cr with the highest metal concentrations detected during autumn. Although many metal concentrations were above the international standards of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO), the hazard quotient (HQ) and hazard index (HI) values for the women in this study indicated that their health was not at risk due to the consumption of either fish or seafood. In contrast, the HQ and HI values determined for groups of men and children indicated that they are at risk due to the frequent consumption of most species evaluated in this study., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Water reservoirs are essential for regional economic development, as populations depend on them for agriculture irrigation, flood control, hydroelectric power generation, water supply for human consumption, and subsistence fishing activities. However, the reservoir environmental quality can be disturbed by enhanced sediment input and trace metal contamination, affecting human health as a consequence of contaminated water and fish consumption. With the purpose to understand the trends and extent of sediment accumulation and trace element contamination in the Oviachic reservoir (OV, northwestern Mexico) since its construction, the temporal variations of sediment accumulation, and As, Cr, Cu, Hg, Ni, Pb, and Zn concentrations, enrichment, and fluxes, were evaluated through the study of two 210 Pb-dated sediment cores. We assumed that siltation and trace element contamination were driven by the development of anthropogenic activities in the region within the past ~ 70 years. Elemental concentrations accounted from null to minor enrichment for most elements, but moderate to significant enrichment by Hg. Mercury, As, and Cu fluxes have notably increased since the past decade, most likely because of a combination of anthropogenic and natural processes, including catchment erosion, artisanal gold mining, and recent drought conditions in the region. Arsenic and Hg concentrations may pose deleterious risks to biota in the reservoir, and consequently to humans through fish consumption, for which further biological and toxicological tests are advisable. This study highlights the importance of using sediment dating to assess historical trends of metal contamination and identify possible sources, to support decision-making in programs addressed to reduce environmental and health risks in aquatic ecosystems.

Mercury and selenium were assessed in Mustelus henlei, which is a carnivorous predatory shark that is important for the coastal communities of the northern Mexican Pacific (NMP). Sixty-two individuals were sampled; muscle and liver were isolated and analyzed by atomic absorption spectrophotometry. The mean Hg concentrations (wet weight) obtained for muscle (0.08 ± 0.10 μg g -1 ) and liver (0.09 ± 0.26 μg g -1 ) were below the allowed limits (< 1.0 μg g -1 Hg). The average Se concentration was 0.03 ± 0.01 μg g -1 in muscle and 0.13 ± 0.05 μg g -1 in liver. The Se/Hg molar ratio of muscle was 1.83; however, the selenium health benefit value (HBV Se ) was of 0.08. We calculated that an adult man (70 kg), an adult woman (60 kg), and a child (16 kg) could consume 1595, 838, and 223 g/week of M. henlei muscle, respectively, without risks to health. In conclusion, the concentrations and molar ratio of Hg and Se in M. henlei muscle mean that consumption of this shark's meat does not represent neither a benefit nor a public health risk.

We studied the biomagnification of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) with carbon (C) and nitrogen (N) stable isotope analyses during four seasons, in the food web of a semiarid coastal lagoon in the central-eastern Gulf of California (GC). The concentrations of the four metals increased among functional organism groups, from the food web base to the highest trophic levels. In general, the distribution of the elements for the four sampled seasons was Zn > Cu > Pb > Cd. The correlations between trophic level values and log-transformed metal concentrations were significantly (p < 0.05) positive for Cd (r = 0.61-0.91), Cu (r = 0.63-0.70), and Zn (r = 0.50-0.73), while Pb showed only one positive correlation (r = 0.38). The biomagnification factors (from specific predator-prey scenarios) ranged from 0.32 to 3.88 for Cd, 0.05 to 37.1 for Cu, 0.50 to 3.57 for Pb, and 0.70 to 22.2 for Zn. The trophic biomagnification factors (considering the entire food web) varied from 1.26 to 1.41 for Cd, 1.95 to 2.24 for Cu, 1.02 to 1.15 for Pb, and 1.45 to 1.78 for Zn. Our results show evidence for the biomagnification of Cd, Cu, and Zn in the studied food web, while data on Pb transference are not conclusive.

In this study, we elucidated the impacts of allochthonous organic matter (OM) and nutrients (N and P) inputs coming from agriculture and shrimp aquaculture activities on food web structure in a subtropical coastal lagoon located on the central-east of the Gulf of California. This coastal lagoon is highly influenced by OM and nutrients inputs by a large agriculture district and aquaculture development center in Mexico. We also selected a second coastal lagoon, without direct OM and nutrients inputs, considered as a 'pristine' ecosystem. We evaluated the quantity of OM, N and P in both ecosystems and reconstructed the food webs using isotopic tools of C and N from the base to top. We collected and analyzed autochthonous and allochthonous OM, and organisms including primary producers, and primary to tertiary consumers. Overall, specimens of the same species and/or functional groups showed higher δ 15 N values in the ecosystem receiving agriculture and shrimp aquaculture effluents than the pristine. Food webs were composed of four and five trophic levels, where fish and birds occupied the top-predator levels. Seasonal increases in OM and N and P quantities in lagoons affected by anthropogenic activities produced high δ 15 N values in primary producers and consumers., (Published by Elsevier B.V.)

With the aim of determining arsenic (As) and selenium (Se) concentrations in bycatch fishes from SW Mexico and comparing elemental concentrations with limits for human consumption set in the national and international legislation, three fish species (Diapterus peruvianus, Pseudupeneus grandisquamis, and Trachinotus kennedyi) were collected from Guerrero state during trawling operations. Additionally, As and Se levels in muscle tissue were compared with similar species from diverse areas. The order of As and Se concentrations was T. kennedyi>P. grandisquamis>D. peruvianus. In Mexico, there is no regulation of As and Se levels in fish. In comparison to the legal limit (0.1 μg g(-1) wet weight) set by legislation in Venezuela, As levels in the edible portion of T. kennedyi (0.632 μg g(-1) wet weight), P. grandisquamis (0.166 μg g(-1) wet weight), and D. peruvianus (0.157 μg g(-1) wet weight) were above this limit. In the case of Se, average concentrations in T. kennedyi (0.323 μg g(-1) wet weight) were above the maximum permissible limit (0.30 μg g(-1) wet weight) set in the Chilean legislation. Se concentrations in Carangoides bajad from Saudi Arabia were comparable to values in T. kennedyi (this study). In relation to As, concentrations varied in magnitude orders; the highest As concentration (range 10.35 to 23.71 μg g(-1) wet weight) corresponded to Mullus barbatus from the Iberian Mediterranean.

The aim of this study was to evaluate Fe and Mn distribution in geochemical fractions of the surface sediment of four oyster culture sites in the Sonora coast, Mexico. A selective fractionation scheme to obtain five fractions was adapted for the microwave system. Surface sediments were analyzed for carbonates, organic matter contents, and Fe and Mn in geochemical fractions. The bulk concentrations of Fe ranged from 10,506 to 21,918 mg/kg (dry weight, dry wt), and the bulk concentrations of Mn ranged from 185.1 to 315.9 mg/kg (dry wt) in sediments, which was low and considered as non-polluted in all of the sites. The fractionation study indicated that the major geochemical phases for the metals were the residual, as well as the Fe and Mn oxide fractions. The concentrations of metals in the geochemical fractions had the following order: residual >> Fe and Mn oxides > organic matter > carbonates > interchangeable. Most of the Fe and Mn were linked to the residual fraction. Among non-residual fractions, high percentages of Fe and Mn were linked to Fe and Mn oxides. The enrichment factors (EFs) for the two metals were similar in the four studied coasts, and the levels of Fe and Mn are interpreted as non-enrichment (EF < 1) because the metals concentrations were within the baseline concentrations. According to the environmental risk assessment codes, Fe and Mn posed no risk and low risk, respectively. Although the concentrations of Fe and Mn were linked to the residual fraction, the levels in non-residual fractions may significantly result in the transference of other metals, depending on several physico-chemical and biological factors.

Oyster fishing in Mexico holds significant importance, but official records show a consistent drop in production. To understand the reproductive behaviour of key oyster species —Crassostrea corteziensis, Saccostrea palmula, and Striostrea prismatica— in a southeastern Gulf of California lagoon (May 2019 to April 2020), this research delved into their reproductive traits. C. corteziensis and S. palmula exhibited five phases of gonadal development, including: undifferentiated/resting, initial gametogenesis, advanced gametogenesis, maturation, and spawning; S. prismatica showed four: undifferentiated/resting, gametogenesis, maturation, and spawning phases. The three oysters displayed hermaphroditism. Spawning peaks varied: C. corteziensis from September to November, S. palmula from May to September, and S. prismatica from August to November. Sex ratio (female:male) of S. prismatica differed from the expected 1:1 proportion. C. corteziensis and S. palmula showed continuous reproduction; S. prismatica displayed a single annual reproductive cycle. Since the obtained peak spawning of C. corteziensis and S. prismatica presented discrepancy with the official protection period and there are no regulatory measures for S. palmula, the information on their reproductive behaviour aids in regulating their extraction for sustainability and conservation in the southeastern Gulf of California. Similar information can be replicated in coastal areas of other latitudes where several oyster species coexist. [ABSTRACT FROM AUTHOR]

Opuntia is a well-known plant for its folkloric use and nutritional composition. This work aimed to evaluate the physicochemical characteristics, as well as the mineral composition realized by inductively coupled plasma-mass spectrometry (ICP-MS) for cultivated and wild Algerian Opuntia species. The results showed a significant difference in length, diameter, and weight between both Opuntia fruits. The highest pH, brix°, and total sugar content were found in the pulp of cultivated fruit compared to the wild one. Moisture was found to be higher in pulp of both species with more than 90% compared to their seeds (33%); however, ashes content was more determined in seeds with 1.04%. Moreover, high protein content was found in wild Opuntia parts (more than 200 mg bovine serum albumin equivalent/100 g dry matter), which also presented higher ascorbic acid and betalain contents, particularly in the pulp with 211.45 mg EAA/100 g DM and 312.91 mg/100 g DM, respectively, compared to the cultivated Opuntia. Finally, the mineral profile revealed a significant countenance of all species' fractions in many important minerals for human organism functioning, like iron, magnesium, zinc, and potassium. [ABSTRACT FROM AUTHOR]

The Tobari Lagoon, located in the central-east coast of the Gulf of California, receives effluents from the Yaqui Valley, one of the most extensive agricultural areas of México. The Tobari Lagoon also receives effluents from nearby shrimp farms and untreated municipal sewage. Surface sediment samples and six different species of filter feeders (Crassostrea corteziensis, Crassostrea gigas, Chione gnidia, Anadara tuberculosa, Chione fluctifraga, and Fistulobalanus dentivarians) were collected during the dry and the rainy seasons and analyzed to determine concentrations of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn). Seasonal variations in metal concentrations in sediment were evident, especially for Cd, Cu, Hg, and Zn. The total and bioavailable concentrations of the five metals are not elevated in comparison to other areas around the world. The percentages of bioavailable respect to total concentrations of the metals varied from 0.6 % in Hg to 50.2 % for Cu. In the organisms, Hg showed the lowest concentrations (ranged from 0.22 to 0.65 μg/g) while Zn showed the highest (ranged from 36.6 to 1,702 μg/g). Linear correlations between the levels of Cu, Pb, and Zn in the soft tissues of C. fluctifraga and C. gnidia, and A. tuberculosa and C. gnidia were found. Seasonal and interspecies variations in the metal levels in filter feeders were found; F. dentivarians, C. corteziensis, and C. gigas exhibited the highest levels, could be used as biomonitors of metals contamination in this area.

The purpose of this research is to provide a comprehensive assessment of the concentration levels and spatial variability of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn) in El Tobari Lagoon in surface sediments during two seasons for several geochemical variables that could explain the observed heavy metal variability. Seventy-two surface sediments samples were collected in 12 different sites of the El Tobari Lagoon. Sediment samples were dried and subjected to acid extraction using a microwave system and five metals (Cd, Cu, Hg, Pb and Zn) were measured using atomic adsorption spectrometry. A certificate sediment material and blanks were used as quality control purposes. The enrichment factor (EF) and the index of geoaccumulation (Igeo) were calculated as index of metals contamination for the sediments, using aluminum as the conservative element. The five metals examined in sediments from El Tobari Lagoon exhibited a linear correlation with Al as result of the large specific surface areas of these sediment components and the chemical affinities between them. The metals contents in sites of the El Tobari Lagoon were variable, and Cd, Cu and Hg presented a seasonal behavior. The enrichment factor and index of geoaccumulation analysis indicated that Cd and Hg exhibited a certain extent (EF for Cd ranged from 4.10 to 10.29; EF for Hg ranged from 2.77 to 12.89) of anthropogenic pollution, while Cu showed sporadic (EF ranged from 0.43 to 2.54) anthropogenic contamination. The highest concentrations of Cd, Cu and Hg were found in the sites that regularly received discharge effluents from agriculture and aquaculture.

Mercury (Hg) transference through an established and defined food web from an urbanized subtropical coastal lagoon (SE Gulf of California) was examined by using carbon and nitrogen stable isotope and Hg analyses. Concentrations of Hg in seawater (0.045-0.078 μg L(-1)), predominantly incorporated to the particulate fraction (60% of total), were lower than those found in highly contaminated coastal areas around the world (0.18-16 μg L(-1)). Although levels of Hg available for the biota (e.g., associated to the reactive and pyrite fractions; 0.11-0.15 μg g(-1)) were within of effects range-low (ER-L, 0.15-0.71 μg g(-1)) these concentrations represented from 46.6 to 67.0% of the total Hg pool that may be transferred through food web. The sequence of bio-accumulation of Hg in studied species was according with their functional guild: tertiary consumer (0.85-1.15 μg g(-1)) > secondary consumers (0.084-0.168 μg g(-1)) > primary consumers (0.014-0.160 μg g(-1)) > primary producers (0.016-0.056 μg g(-1)). Hg concentrations increased for each successive trophic position estimate through δ(15) N isotopic values, although these relationships showed differences between dry and rainy seasons (R(2) = 0.37 and R(2) = 0.39 between δ(15) N vs. Hg in organisms, respectively). We concluded that Hg is being positively transferred (biomagnification factor >1) through the studied food web probably enhanced by the favorable environmental conditions for Hg-methylation (e.g., fine sediments rich in organic matter, and environmental conditions changes of the redox, pH, and temperature) found in this urbanized coastal water, however, the study of processes methlylation and biomagnifcation of Hg need further investigations., (Copyright © 2011 Wiley Periodicals, Inc.)

The objective of this investigation was to assess the transfer of lead (Pb) along an experimental, four-level food chain: Tetraselmis suecica (phytoplankton) → Artemia franciscana (crustacean, brine shrimp) → Litopenaeus vannamei (crustacean, white shrimp) → Haemulon scudderi (fish, grunt). T. suecica was exposed to a sublethal dose of Pb in solution and then used as the base of a marine food chain. Significant differences in Pb concentrations were found between exposed organisms of the different trophic levels and the control. Particularly, Pb concentrations in fish of the simulated trophic chain were two-to three times higher in the exposed specimens than in the control. Levels of Pb in phytoplankton showed a substantial increase with respect to the solution (level I), with bioconcentration factors averaging from 930 to 3630. In contrast, a strong decrease in Pb concentration from phytoplankton to zooplankton (level II) and from zooplankton to shrimp tissues (level III) was evidenced by bioaccumulation factors <1. Despite the decrease in the assimilation efficiency of metal transfer observed in these two predators, Pb concentration in the grunt fish (level IV) was higher than in the shrimp (level III) (bioaccumulation factor >1.0). Some of the added Pb is transferred from the phytoplankton along the food chain, thus producing a net accumulation of Pb mainly in fish and, to a lesser extent, in shrimp tissues. Because Pb is one of the most pervasive contaminants in coastal ecosystems, its transference by way of diet and potential net accumulation in higher predators is of ecologic importance for marine life. In addition, because shrimp and adult Haemulon scudderi are commercially important resources, this issue is of particular relevance to the safety of marine products.

This investigation sought to assess the biological responses to Pb along a simplified four-level food chain, from the primary producer, the microalgae Tetraselmis suecica, grown in a control medium with < 1 µg/L of Pb and exposed to a sublethal dose (20 µg/L of Pb) and used as the base of a simulated food chain, through the primary-, secondary-, and tertiary-level consumers, namely, the brine shrimp, Artemia franciscana; the white-leg shrimp, Litopenaeus vannamei; and the grunt fish, Haemulon scudderi, respectively. Growth of Pb-exposed T. suecica was 40% lower than that of the control cultures, and survival of A. franciscana fed this diet was 25 to 30% lower than the control. No differences in the growth rates of Pb-exposed and control shrimp and fish and no gross morphological changes were evident in the exposed specimens. However, the exposed shrimp and fish had 20 and 15% higher mortalities than their controls, respectively. In addition, behavioral alterations were observed in exposed shrimp and fish, including reduction in food consumption or cessation of feeding, breathing air out of the water, reduction of motility, and erratic swimming. The negative correlation between Pb concentration in whole body of shrimp and fish and Fulton's condition factor suggested also that the exposed organisms were stressed because of Pb accumulation., (Copyright © 2011 SETAC.)

The purpose of this study was to investigate the distribution of metals (Cd, Pb, Hg, Cu, Fe, Mn, and Zn) in dissolved and particulate fractions in seawater from Bacochibampo Bay, Northern part of Mexico. Water samples were collected from November 2004 to October 2005. Metal analysis was done by graphite furnace atomic absorption spectroscopy. Results indicated highest concentrations of dissolved Cd and Zn in the sites localized at the mouth and center of the bay. During summer and spring, the highest levels of Cd, Mn, and Fe were detected, Zn in fall, and Pb and Cu in winter and spring. Mercury was the only metal that was not found in this fraction. In particulate fraction, Fe, Hg, and Mn were the most abundant elements in all the sampling sites, followed by Zn, Cu, Pb, and Cd. The highest levels of the majority of the metals were observed in the coastline, suggesting a continental and/or urban source for these chemicals. The highest level of Cd was detected during the summer and the rest of the metals in the fall. Statistically significant correlations were observed between dissolved and particulate forms of Pb:Mn, Cu:Fe, and Cu:Mn. The mean partition coefficient values were as follows: Fe>Mn>Cu>Pb>Cd>Zn. All dissolved metal concentrations found, except Pb, were lower than EPA-recommended water quality values. The levels of dissolved metals in this study reveal low bioavailability and toxic potential. However, further toxicological and sediment chemistry studies in this area are needed for a full risk assessment.

Trophic relationships and heavy metal transference in a coastal subtropical lagoon marine food web were investigated through the use of stable isotopes in food sources and biota. A selective extraction scheme was applied to the surface sediments as an indirect way to evaluate the potential of toxicity of metals. Results showed that cadmium, copper, lead and zinc concentrations were within sediment quality guidelines criteria. Concentrations of these metals in organisms varied widely among functional groups and within the same and closely related taxa. delta(13)C values varied significantly among organisms from different functional groups, while the delta(15)N values varied according with their feeding habits. Cd, Cu, Pb, and Zn were not positively transferred (biomagnification factor <1) through entire food web. However, a partial positive transference was observed for Cu and Zn involving three trophic levels (from the phytoplankton to crab as secondary consumer).

Total mercury (Hg) and selenium (Se) contents were determined in oysters Saccostrea palmula and Crassostrea corteziensis soft tissues from four coastal lagoons of the southeastern Gulf of California. The annual Hg mean concentrations for S. palmula (0.09 ± 0.04 µg g - 1 , wet weight) and C. corteziensis (0.08 ± 0.04 µg g - 1 ) were similar (p ˃ 0.05) among the lagoons and did not exceed the limit established by the Norma Oficial Mexicana and World Health Organization (< 1.0 µg g - 1 Hg). On the other hand, the annual mean concentrations of Se for S. palmula (3.34 ± 0.96 µg g - 1 ) and C. corteziensis (2.79 ± 0.89 µg g - 1 ) were higher (p < 0.05) in El Colorado lagoon. The Se/Hg molar ratios were above 1; the positive selenium health benefit value index suggested that Se load in oysters could reduce the Hg potential toxic effect. The hazard quotient for Hg in both species was below 1. Therefore, the consumption of oysters does not represent a risk due to Hg ingestion., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Water, surface sediments, the mussel Mytella strigata, the mangrove oyster Crassostrea corteziensis, and the green macroalgae Caulerpa sertularioides from four locations in Mazatlan Harbor on the southeast coast of the Gulf of California, were analyzed to determine concentrations and distribution patterns of cadmium, copper, mercury, lead, and zinc. Total metal concentrations in water in the present study exceed the background levels in open sea and coastal waters. Total metal concentrations in sediments were ordered as follows: Zn > Pb > Cu > Cd > Hg, but for the bioavailable fraction were ordered as Zn > Cu > Pb > Cd > Hg. The concentrations in bioavailable levels fall between the Threshold Effects Level (TEL), and Probable Effects Level (PEL), criteria for sediment quality. Distribution patterns for metals in organisms were ordered Zn > Cu > Pb > Cd > Hg with seasonal variations for Pb and Zn. Correlations between Cd, Cu, Pb and Zn were indicative of similar assimilation and storage mechanisms and common sources of contamination. These correlations also indicated that bioavailability was not simultaneous for Cd and Pb. Bioconcentration factors (BCF) show different patterns in different organisms. For the oyster the metals were ordered Zn >> Cu > Cd approximately Hg > Pb, for the mussel Hg > Cu approximately Zn approximately Cd > Pb and for the macroalgae Zn >> Cu > Pb > Cd > Hg. Based on BCF results in the lagoon system, the oyster C cortezienzes can be used as a biomonitor of Zn and Cu exposure, the mussel M. strigata of Hg exposure and the green macroalgae C. serticularioides of exposure to all five metals studied.

This work evaluates current metal concentrations (Cd, Cu, Pb and Zn) and the operational bio-available chemical extraction fraction in surface sediments in Mazatlán Harbor in Northwest México. Sediment samples were also analyzed for organic carbon, carbonates and particle size. Ranges of bulk metal were as follows: Cd from 3.1 to 3.3 microg/g, Cu from 31.9 to 44.9 microg/g, Pb from 49.6 to 54.0 microg/g, and Zn from 217.8 to 323.5 microg/g. In terms of biological effects, metals concentrations in the sediments lie between the low and median ranges of the mean quality guideline criteria. Comparatively, the metals concentrations increased from 1983 to 1994 and then for 2006, except Pb and Cd that decreased in the last period of time. The bio-available fraction of metals increased from 1983 to 1994, but only bio-available Cu increased from 1994 to 2006, due to mobilization of this metal from the organic matter-sulfide phase.

This study investigates the presence of Cu, Zn, Cd, Pb, and Hg in 24 dietary supplements purchased in different health stores across the city of Hermosillo, located in the northwest of Mexico. Analysis of metals was done by microwave digestion and atomic absorption spectroscopy. The most abundant elements in dietary supplements were Cu (<0.19-137.85 microg/g) and Zn (<2.83-4785.71 microg/g), followed by Pb (<0.003-66.32 microg/g), Cd (<0.001-2.90 microg/g), and Hg (<0.24-0.85 microg/g). The estimated daily intakes of metals were below those recommended by WHO and the Institute of Medicine, showing that little risk from heavy metals is associated with the consumption of the dietary supplements analyzed. However, some products presented more than 10% of the tolerable daily intake of Pb, indicating that production processes should be improved.

In early April 2003, fishermen from Kino Bay Sonora alerted us about a massive die-off of fish and mollusks occurring at Kun Kaak Bay. Phytoplankton samples taken on 17 May 2003 reported the presence of a harmful algal bloom composed of Chatonella marina, Chatonella cf. ovata, Gymnodinium catenatum and Gymnodinium sanguineum. On 22 of May, we collected samples of water, sediment and organisms at the affected area. Physicochemical parameters and nutrients were measured in water samples from different depths. Sediment and benthic organisms were analyzed for Cd, Cu, Zn, Pb and Hg. We found concentrations of heavy metals higher than background levels for this area. Cadmium and Lead concentrations in sediment from the HAB area were up to 6x greater than background levels and Cd in mollusks was 8x greater than regulations allow. A relationship between elevated Cd and Pb concentrations in sediment and the survival of toxic dinoflagellates is suspected.

Although various studies have reported the bioaccumulation of metals in bivalves of commercial interest from the Gulf of California (GC), the risk associated with their consumption remains poorly understood. In this study, our own and bibliographic concentrations of 14 elements in 16 species of bivalves from 23 locations were used to investigate (1) the species-specific and regional accumulation of metals and arsenic in bivalves, (2) the human health risks by age and sex, and (3) the maximum allowable consumption rates (CRlim). The assessments were done according to the US Environmental Protection Agency guidelines. The results indicate that the bioaccumulation of elements varies markedly between groups (oysters > mussels > clams) and localities (higher on Sinaloa due to intense anthropogenic activities). However, consuming bivalves from the GC remains safe for human health. To prevent health effects for residents or consumers on the GC, we recommend (1) following the CRlim proposed herein; (2) monitoring levels of Cd, Pb, and As (inorganic) in bivalves, as the elements of top concern, mainly when are consumed by children; (3) calculating CRlim for more species and locations, including at least: As, Al, Cd, Cu, Fe, Mn, Pb, and Zn; and (4) determine the regional consumption rates of bivalves., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Information of essential elements in sharks are still limited, especially from Indonesian waters. The aims of this study were to report the concentration of 12 elements (Mg, Ca, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Sr, and Mo) using inductively coupled plasma–mass spectrometry (ICP-MS) in Sphyrna lewini (hammerhead shark) and Rhizoprionodon acutus (milk shark) from West Java waters, Indonesia. The results of this study showed that the concentration of Mg, Ca, Fe, Mn, Zn, Cu, and Sr in S. lewini are higher than in R. acutus. The chemometrics analysis using partial least squares-discriminant analysis (PLS-DA) showed that total length (TL), total weight (TW), Co, Se, V, and Cu concentration were important variables in sample classification to determine milk shark and hammerhead shark. Overall essential elements in sharks showed positive correlation to morphometric and metal–metal correlation. [ABSTRACT FROM AUTHOR]

Multivitamin/mineral (MVM) supplements are the most commonly utilized dietary supplements by many populations. However, there is a severe concern about their adverse effects due to elemental impurities. In the present study, it was aimed to determine the levels of 11 elemental impurities (Cd, Pb, As, Hg, Co, V, Ni, Se, Mo, Cu, and Cr) by inductively coupled plasma-mass spectrometry (ICP-MS) and evaluate the human health risk associated with the consumption of 33 MVM effervescent tablet supplements available in Turkey. The precision of the method in terms of relative standard deviation (RSD) was less than 4.6%. The accuracy of the method was tested with recovery experiments, and the results ranged between 86 and 107%. The impurity levels for Cd, Pb, As, Co, V, Ni, Se, Mo, Cu, and Cr were found between 0.011-0.050, 0.025-0.098, 0.018-0.056, 0.010-0.626, 0.027-0.290, 0.026-1.65, 1.92-21.83, 0.034-34.09, 0.140-183.9, and 0.033-13.10 µg/g, respectively, and Hg was not detected in any sample. The calculated concentrations for elemental impurities complied with EMA and USP guidelines, except one supplement for Se (21.83 µg/g) with a permitted limit of 15 µg/g. The hazard quotient (HQ) and hazard index (HI) levels were below 1 for all samples within the ranges of 3.4 × 10 -1 -1.4 × 10 -6 for HQ and 7.8 × 10 -1 -1.4 × 10 -6 for HI indicating that there is no risk for consumption. The carcinogenic risk (CR) of As was between 1.7 × 10 -6 and 5.9 × 10 -6 , below the threshold value of 1 × 10 -4 . The results showed that there is no risk to human health., Competing Interests: Declarations. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Metal concentrations (Cu, Cr, Ni, Zn, Fe, Mn, Cd, and Pb) in marine indicator species were assessed for the study of metal pollution in the Eastern Ionian Sea during the cold period of the year (December 2018 to February 2019). Limpets and sea urchins were collected from natural populations at seven coastal stations while mussels were transplanted at three near-shore stations in the study area. Mixed mesozooplankton samples were selected from a twelve-station offshore network. Additionally, fish, shrimp, and shortfin squid samples were collected by trawling. For the first time, metal concentrations in marine animals were measured in an extended variety of organisms in the area. Higher metal concentrations in limpets, sea urchins, and mussels were observed in the wider area of the two ports located at the sampling area's eastern and southern geographical borders. Levels in zooplankton also followed the same spatial variation. In general, metal concentrations in the investigated organisms were within the same range as those in other non-impacted Mediterranean areas. Accordingly, metal levels in the flesh of the fish, shrimps, and the mantle of shortfin squids did not reveal any risk for human consumption. Metal levels from the present study are proposed as a reference state for the area, while future deviations should be evaluated taking into account potential changes in the natural and anthropogenic pressures on the specific coastal marine ecosystem., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Elemental ratios (δ13C, δ15N and C/N) and carbon and nitrogen concentrations in macrophytes, sediments and sponges of the hypersaline Al-Kharrar Lagoon (KL), central eastern Red Sea coast, were measured to distinguish their sources, pathways and see how they have been influenced by biogeochemical processes and terrestrial inputs. The mangroves and halophytes showed the most depleted δ13C values of –27.07±0.2 ‰ and –28.34±0.4 ‰, respectively, indicating their preferential 12C uptake, similar to C3-photosynthetic plants, except for the halophytes Atriplex sp. and Suaeda vermiculata which showed δ13C of –14.31±0.6 ‰, similar to C4-plants. Macroalgae were divided into A and B groups based on their δ13C values. The δ13C of macroalgae A averaged –15.41±0.4 ‰, whereas macroalgae B and seagrasses showed values of –7.41±0.8 ‰ and –7.98 ‰, suggesting uptake of HCO3– as a source for CO2 during photosynthesis. The δ13C of sponges was –10.7±0.3 ‰, suggesting that macroalgae and seagrasses are their main favoured diets. Substrates of all these taxa showed δ13C of –15.52±0.8 ‰, suggesting the KL is at present a macroalgae-dominated lagoon. The δ15N in taxa/sediments averaged 1.68 ‰, suggesting that atmospheric N2-fixation is the main source of nitrogen in/around the lagoon. The heaviest δ15N (10.58 ‰) in halophytes growing in algal mats and sabkha is possibly due to denitrification and ammonia evaporation. The macrophytes in the KL showed high C %, N %, and C/N ratios, but this is not indicated in their substrates due possibly to a rapid turnover of dense, hypersaline waters carrying most of the detached organic materials out into the Red Sea. The δ13C allowed separation of subaerial from aquatic macrophytes, a proxy that could be used when interpreting paleo-sea level or paleoclimatic changes from the coastal marine sediments. [ABSTRACT FROM AUTHOR]

In recent years, the Vietnamese government has dedicated considerable planning and resources toward agricultural restructuring. These far-reaching efforts include promotion of intensive shrimp farming in the Mekong Delta to encourage the sustainable development of rural livelihoods. However, while intensive shrimp production may improve economic wellbeing, the current production practices raise concerns about the impacts on the local environment. The current study examines the economic and environmental efficiencies associated with the two primary species of farmed shrimp in four coastal provinces of the Mekong Delta. The study employs the material balance principle as a framework which considers the inputs to production and the outputs which may be undesirable. Using the efficiency estimates, we measure and investigate the trade-offs between the economic and environmental efficiencies for the shrimp farming in the Vietnamese Mekong Delta. The results suggest that the shrimp farming produces a significant nutrient surplus for either species. The analysis also suggests that achieving cost efficiency and environmental efficiency would help the shrimp farmers to reduce the undesirable outputs and that the movement from the cost efficiency to the environmental efficiency could result in a reduction of both production costs and nutrients. Based on these results, we offer policy recommendations for economically feasible and environmentally friendly shrimp farming. The material balance approach provides a useful lens through which to investigate agricultural production. [ABSTRACT FROM AUTHOR]

While the role that groundwater discharge plays in supporting primary production in coastal ecosystems is well recognized, there is still limited evidence on its impacts higher up the food chain. In this study, we investigate the role of groundwater discharge in supplying nitrogen and carbon to the Mediterranean mussels (Mytilus galloprovincialis) in the Salses-Leucate lagoon (France). Nitrogen (δ15N) and carbon (δ13C) isotope values in the mantle and gill tissues of Mediterranean mussels are used to trace nitrogen and carbon sources at groundwater-exposed sites and a control site. Our results show similar isotope values for mantle and gill tissues, likely due to relatively stable environmental conditions in the study sites and to the biochemical composition of tissues. Diet shift, fractionation, and the physiological function of tissues could also explain this observation. δ15N values in mussel tissues increase overall in winter at both the groundwater-influenced sites (4.9 to 7.8‰) and the control site (3.4 to 8.5‰) in comparison with those in autumn (3.5 to 7.4‰ at the groundwater-influenced sites and 4.5 to 6.9‰ at the control site), likely due to reduced food supply and slower metabolism in winter, resulting in 15N enrichment. In contrast, mussel δ13C values decrease in winter at the groundwater-influenced sites (− 23.4 to − 21.6‰) and the control site (− 22.0 to − 19.0‰), suggesting input from 13C-depleted sources originating from groundwater input. The comparison of the isotopic values of mussel tissues and potential food sources indicates that the main diet of M. galloprovincialis in the Salses-Leucate lagoon is a mixture of groundwater particulate organic matter (POM), lagoon POM, and marine POM (POM as a proxy of phytoplankton). Depleted δ13C values in mussel tissues, particularly at groundwater-exposed sites, provide evidence of uptake of groundwater-derived nutrients. The ecological benefit of groundwater input on filter feeders results from local increases in food availability (mainly phytoplankton), supported by groundwater-derived nitrogen and carbon. In summary, this study shows the combined (a) indirect effect of groundwater discharge on mussel growth via uptake of their food, phytoplankton, and (b) the likely direct feeding of groundwater POM by M. galloprovincialis. It thus shows the important ecological implication of groundwater inputs in coastal lagoon food webs. [ABSTRACT FROM AUTHOR]

During January 2013, a mining spill occurred in the Santa Maria mining region, releasing around 300,000 m3 of tailings on Los Remedios river, which was transported through the San Lorenzo river and finally to El Comedero (EC) dam. Twenty months later, we examined the concentrations of Hg and Se in the muscle, liver, gills, and guts of three fish species (Cyprinus carpio, Oreochromis aureus, Micropterus salmoides) captured in the EC dam to assess the performance of the cleaning operations. A high Se concentration in the liver of all species (carp, 1.2 ± 0.4; tilapia, 3.9 ± 2.1; bass, 3.5 ± 1.1 µg g−1 ww) was consistently observed, while this behavior was only found in the blue tilapia for Hg (0.15 ± 0.11 µg g−1 ww). Tilapia (benthic-detritivorous) exhibited the highest Se concentrations compared to the carp (omnivore) and the largemouth bass (piscivore). In contrast, the largemouth bass had the highest Hg levels in the muscle compared with the other fishes. Such differences could be related to the different metabolism and feeding habits among species. Compared to a tilapia study carried out three months after the mine spill during a mortality event, a decrease was evident in the liver for Se and Hg by 7.2 and 4.7 times, respectively. This reveals that cleaning operations were more efficient for Se and less for Hg, and that a prolonged period was required for the partial recovery of the element levels in fish from sites impacted by mining. Considering the Mexican consumption scenarios for each fish species, it could be concluded that there will be no non-cancer risk by exposure to Hg or Se. [ABSTRACT FROM AUTHOR]

An increasing number of organic and inorganic pollutants are being detected in the marine environment, posing a severe threat to the ecosystem and human health, even in trace concentrations. Isotope ratio mass spectrometry (IRMS) is one of the critical methods for determining the origin and fate of environmental pollutants and characterising their transformation processes. It has been used for a relatively long time for ecological monitoring of some well-studied industrial hydrocarbons at contaminated sites. However, the method still faces many analytical challenges. This review provides a comprehensive overview of recent technical advances concerning IRMS analysis of various contaminants and discusses typical pitfalls encountered in marine environment analysis. Particular attention is given to the study of sampling techniques and sample preparation for examination, often the keys to successful research given the complexity of marine matrices and the diverse and numerous nature of contaminants. Prospects for developing IRMS to monitor pollution sources and pollutant transformation in the marine environment are outlined. [ABSTRACT FROM AUTHOR]

Lead (Pb) is ubiquitous in urban environments, and it is a risk factor for wildlife. But wildlife are particularly at risk for exposure near smelters in urban areas where higher than safe Pb levels in the soil have the potential to transfer to the food chain. Therefore, we investigated whether wildlife are at risk of Pb exposure and differences in Pb bioaccumulation in trophic levels at a Superfund site in an urban area of Colorado. We sampled soil, vegetation, arthropods, and birds at four sites: two contaminated sites (one at the Superfund site and one near the Superfund site) and two reference sites with low predicted Pb contamination. We found significantly higher Pb levels in the soil at the contaminated Slag pile at the Superfund site, compared to the other sites. At the Slag pile, Pb levels were the highest in vegetation and both arthropods and birds accumulated Pb. However, Pb did not increase between trophic levels in the terrestrial food web at the site. We concluded that smelter operations at the Superfund site resulted in significantly higher levels of Pb in the soil and sublethal accumulation in all taxa studied. This research can be used to mitigate the risks to vulnerable wildlife populations exposed to Pb at the Superfund site. Further examination of Pb toxicity in vulnerable taxa is critical to conserving wild populations and ecosystems near contamination zones. [ABSTRACT FROM AUTHOR]

This study analyzed the effects of cadmium (Cd) and lead (Pb) on growth, sexual couples, and histological structures of Artemia franciscana exposed to individual concentrations of these metals and combined. No histological effects were observed at tissue level in digestive, respiratory, nervous, and reproductive systems (i.e., necrosis, loss of regular structure) in individual and mixed applications on A. franciscana for 20 days of exposure. No significant differences (p > 0.05) were determined in final size and growth rate among the organisms exposed to Cd and those of control. For Pb, only the final size (3.59 ± 0.59 mm) of organisms exposed to the highest concentration was significantly lower (p < 0.05) than those of the control (4.53 ± 0.34 mm) group, whereas for the combined experiment, no significant differences (p > 0.05) were observed in final size and growth rate. At all Cd concentrations, mean sexual couples were significantly lower (p < 0.05) than those of the control, as well as for Pb. For the combined experiment (8 μg/L of Cd + 8 μg/L of Pb), sexual couples were not observed, indicating synergism and negative reproduction effects. The results showed that Cd and Pb aquatic environmental regulations (as the Criterion of Continuous Concentration) proposed by the US Environmental Protection Agency (EPA) should include their interactions with other metals., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Trace metals have been found in sea turtle blood and tissues and may represent a threat to these endangered species. Essential trace metal (Cu, Zn Cd, Pb, As, and Hg) concentrations were determined in blood of adult female, post-nesting olive ridley turtles Lepidochelys olivacea (n = 35) on Ceuta beach, Sinaloa, Mexico. Essential metals (Zn and Cu) analyzed were found in higher concentrations than toxic metals (Cd and Pb), while As and Hg concentrations were below the limits of detection (0.01 μg g -1 ). Low Pb concentrations (0.09 μg g -1 ) were previously observed in sea turtles in the Gulf of California. There were no significant correlations found between curved carapace length (61.00-71.00 ± 2.29) vs metal concentrations (p > 0.05). Cd levels were relatively high when compared to other species and populations of sea turtles worldwide and Cd may represent the greatest risk for sea turtles in the Mexican Pacific. Such concentrations of Cd may pose a further risk to sea turtles through bioaccumulation from the nesting female to offspring which may affect embryo development.

Coastal lagoons are vulnerable to eutrophication processes. In this study, we evaluate the eutrophication process in the restricted, arid subtropical Tóbari coastal lagoon, located in the eastern coast of the Gulf of California, where the main source of nutrient inputs and other pollutants is agricultural wastewater from the Yaqui Valley. The Assessment of Estuarine Trophic Status (ASSETS) model and the Trophic State Index (TRIX) were used to evaluate eutrophication. Overall, ASSETS showed that the Tóbari lagoon has a moderate eutrophication process, with seasonal symptoms of hypoxia, increased phytoplankton biomass, dominance of macroalgae (indicative of nutrient enrichment), and blooms development of potentially harmful algae species. The TRIX showed that the lagoon is mesotrophic most of the year. Challenges of environmental management detected correspond to reducing the input of nutrients and others contaminants from anthropic sources: agriculture, shrimp farming, livestock, and urban zones. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in surface water is widespread throughout the world as a result of numerous anthropogenic activities and geo-genic mechanisms. This contamination is also affecting aquatic life, as fish have the potential to acquire heavy metals in their tissues making them vulnerable. Worldwide lakes are an important source of water for the inhabitants of the area. So, in the present study, we have focused on the Satpara Lake to check the extent of heavy metal pollution and their accumulation in fish to provide baseline data for metal pollution management. Samples were collected from three locations (inflow, center, and outflow sites) during two seasons (summer and winter). Inductively coupled plasma optical emission spectrometry (ICP-OES) was applied to analyze heavy metals concentration. Among the metals, Cd, Pb, As, and Fe revealed relatively higher concentrations. The highest concentration of heavy metal found in water and fish was of Cd, i.e., 8.87 mg L−1 and 18.19 mg L−1 in summer season, respectively. Arsenic concentration was also higher than the permissible limits in both water (0.76) and fish (1.17 mg L−1). The water quality assessment showed that in the summer season, the HPI (heavy metal pollution index) value 253.01 was more than 100, indicating the bad quality of water for drinking purposes. However, the HPI value 35.72 was less than 100 in winter. Toxicity hazard calculation of fish in summer seasons gives Hi values greater than 10.0, indicating the acute effect on human health as compared to winter. [ABSTRACT FROM AUTHOR]

The failure of a tailings dam occurred in January 2013 at the Santa María de Otáez mining region (Mexico) released a spill (~ 300,000 m3) on Los Remedios River, which was transported through the San Lorenzo River, and finally to El Comedero (EC) dam. The concentrations of metal(loid)s in the muscle, liver, gills, and guts of three fish species (Cyprinus carpio, Oreochromis aureus, Micropterus salmoides) collected from EC dam were examined twenty months later to assess the performance of the cleaning operations. The bioaccumulation patterns of the metal(loid)s in the tissues were different in the three fish species. Tilapia had the highest Cd (11.23 ± 8.53 µg g−1) and Cu (871 ± 1261 µg g−1) concentrations in the liver, as well as As concentration (83.6 ± 61.7 µg g−1) in the gut, while the highest Zn concentration (745 ± 356 µg g−1) was measured in the gills of the carp. Such variability can be caused by the variant bioavailability of the metal(loid)s and by the feeding habits of each species; and also by the fact that some metals are essential and better regulated by organisms than other non-essential. Compared to a study of tilapia carried out 90 days after mine spill, a decrease was evident in the liver for As, Cd, Cu, and Zn by 129, 5, 10, and 1.7 times, respectively. This revealed that cleaning operations were more efficient for As. The target hazard quotient and the hazard index were < 1, which indicates there will be no risk of consuming muscle in moderated rations of the three fish species. [ABSTRACT FROM AUTHOR]

In this study, the concentration of six metal(loid)s was examined in the fish Oreochromis aureus collected from El Comedero dam during a massive mortality event induced by a mine tailing spill. A major spill (~ 300,000 m3) of waste was released into the San Lorenzo River System following a rupture in the tailing dam of a mining plant in NW Mexico; consequently, the discharged material flowed into El Comedero dam. The accumulation of metal(oid)s in the tissues of O. aureus showed higher levels in the liver than in the guts and muscle. Concentrations in the liver were high (As, 1.1–1063; Cd, 8.9–392; Cu, 372–59,129; Hg, 0.46–19.79; Se, 8.7–748; and Zn, 116–820 μg g−1), revealing that these fish were exposed to high concentrations of these elements. The mortality of fish could have resulted from the combined effect of the six analyzed metal(loid)s, as well as other residues present in mine tailings. [ABSTRACT FROM AUTHOR]

This study aimed to establish the distribution of As, Cd, Cu, Pb, and Zn, in the muscle and liver of the spotted ratfish Hydrolagus colliei from the northern Gulf of California to establish the bioaccumulation background data in this species. The individuals (n = 110) were obtained by bycatch from the Gulf of California hake fisheries, and the metals and metalloid were measured by atomic absorption spectrometry. The element with the highest concentration in the muscle (15.19 ± 5.40 mg kg−1) and the liver (20.98 ± 10.30 mg kg−1) was As, followed by essential elements (Zn > Cu), and the lowest were the non-essential Pb (0.029 ± 0.014 and 0.048 ± 0.038 mg kg−1, muscle and liver, respectively) and Cd (0.022 ± 0.014 and 0.796 ± 0.495 mg kg−1, muscle and liver, respectively). The liver showed higher bioaccumulation than the muscle in all the studied elements. The sex was not a factor that influenced the bioaccumulation. The concentrations of As in the muscle did not exceed the maximum permissible limits of Mexican legislation, and < 50% of the samples exceed Cd and Pb limits of the Mexican, European Union, and WHO/FAO regulations. The differences found between the elements and tissues could be related to the different diets of the species, their migratory patterns, and their life conditions. Studies in the deep-sea water H. colliei are limited, and further investigations are needed regarding the feeding habits of H. colliei as well as the interactions of potentially toxic elements within the deep-sea water habitat. [ABSTRACT FROM AUTHOR]

The coastal lagoons of the Gulf of California support important traditional fisheries and mollusc cultures (generally oysters) and receive important volumes of agricultural, industrial and urban effluents, consumption of the oysters could pose risk to human health. The concentrations of arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn) in the oysters Saccostrea palmula and Crassostrea corteziensis, from four coastal lagoons (Altata, AL; Macapule, ML; Navachiste, NL; El Colorado, ECL) in the Southeast Gulf of California, were seasonally evaluated (summer 2019–spring 2020). The order of magnitude of potentially toxic elements concentrations in the soft tissue in both oyster species and at all sites was Zn > Fe > Cu > As > Cd > Pb. Cadmium, Cu, Pb, and Zn exceeded the maximum permissible limits in more than one sampling site. The highest concentrations (mg kg–1, wet weight) of As (4.2 ± 1.1, spring) and Cd (3.3 ± 0.7, autumn) were registered in S. palmula et al. and NL sampling sites, respectively. Crassostrea corteziensis presented higher levels of Cu (40.5 ± 6.7, spring), Pb (2.0 ± 0.4, spring), and Zn (96.9 ± 20.4, spring) in ECL and Fe (62.2 ± 25.4, autumn) in ML. The hazard quotient (HQ) values exceeded the safe level of 1 for Cd in S. palmula and C. corteziensis in NL for children (~ 16 kg weight). In addition, in children, the hazard index (HI) values in both species of oysters ranged from 0.7 to 2.1 and 0.6 to 1.9, respectively. On the other hand, the intake of the studied elements through the consumption of oysters would not induce adverse effects to human health (men and women weighing 70 and 60 kg, respectively); HQ and HI values were < 1. [ABSTRACT FROM AUTHOR]

The occurrence and contamination level of seven important toxic metals (Cd, Cu, Co, Cr, Hg, Pb, and Zn) and three additional metals (Al, Fe, and Mn) in the water, sediment, and shrimp muscle in aquaculture areas located in Central Java, Indonesia, were investigated. The results suggest that the majority of metals have higher concentrations in the inlet followed by the outlet and ponds. Cd dissolved in the waters exhibited the highest level in Pekalongan (3.15 ± 0.33 μg L -1 ). Although Pb was not detected in the water, it was detected in the sediment, and the concentration ranged from 7.6 to 15.40 mg kg -1 dw. In general, the heavy metal concentrations in the sediments were found to decrease in the sequence Al > Fe > Mn > Zn > Cr > Cu > Co > Pb. Concentrations below the effects range low level based on the Canadian sediment quality guidelines were found for Cr, Cu, Pb, and Zn, whereas moderate sediment pollution (25-75 mg kg -1 dw) was observed for Cr (all regions), Cu (except in the Pekalongan region), and Zn (Brebes and Tegal regions) according to the US EPA standard. The status of the waters was evaluated by calculating a pollution index derived mostly from Mn and Zn. The ecological risk (geoaccumulation index (I geo ), contamination factor (CF), pollution load index (PLI), and potential ecological risk index (ERI)) determined in the sediments indicated that all studied areas had low to moderate contamination. The concentrations of all metals in shrimp were generally below the maximum limits for seafood, except for Zn (in all stations), Pb, and Cr (Tegal and Pekalongan). The hazard index values for metals indicated that consuming shrimp would not have adverse effects on human health.

We aimed to examine the responses of pollution biomarkers in feral fish from Astyanax genus collected at three hydrographic regions in southern Brazil and the capacity of these tools to differentiate between various levels of contamination. To achieve this, levels of organochlorine pesticides (liver), as well as the biomarkers AChE (muscle and brain), TBARS (liver), and EROD (liver) were assessed. Collections were conducted in four municipalities (Alegrete, Caraá, Lavras, and Santa Vitória) during 1 year, encompassing winter and summer. Fish from Alegrete were the most contaminated overall, but animals sampled in Caraá, and Lavras also displayed elevated levels of current-use pesticides. Elevated levels of endosulfans, DDTs, HCHs, and current-use pesticides were accompanied by elevated levels of TBARS in the liver. Conversely, fish from Santa Vitória exhibited the highest levels of PAHs, accompanied by elevated levels of EROD in the liver and reduced levels of AChE in muscle and brain. TBARS proved to be a reliable biomarker for assessing impacts arising from pesticide accumulation, while EROD and AChE served as valuable indicators of impacts resulting from PAHs accumulation. Ultimately, the results obtained in this study demonstrate the reliable use of the proposed biomarkers for tracking biological impacts stemming from aquatic pollution using feral Astyanax as biomonitoring species., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)