Study of temporal trends in mercury concentrations in the primary flight feathers of Strix aluco.

Temporal trends in Hg concentrations were determined in the primary flight feathers of 146 specimens of Strix aluco which had died in various Wildlife Recovery Centres in Galicia (NW Spain) between 1997 and 2014. The aim of the study was to determine whether standardization of a primary flight feather (or feathers) in this species is essential for identifying temporal trends in Hg concentrations. For this purpose, we had to first standardize the feather(s) analyzed to enable comparison of the levels of Hg detected in different feathers. The results show a high degree of both inter and intra-individual variability but despite that, it was possible to identify P5 as the most representative feather taking into account the amount of metal excreted in each feather and the intra-individual variability: its median was 133ng, which represents 15% (from 7% to 15%) of the total Hg present in all the primary feathers. However, this "standard feather" did not reveal any temporal trend in Hg concentrations for the study period. This lack of trend was found irrespective of the feather considered and it is expected that detection of any existing trend would also not depend on the feather considered. We conclude that use of any particular feather is not essential for identifying temporal trends in Hg concentrations, because the pattern will be identified regardless of the feather selected.

Active biomonitoring with the moss Pseudoscleropodium purum: Comparison between different types of transplants and bulk deposition.

Active biomonitoring with terrestrial mosses can be used to complement traditional air pollution monitoring techniques. Several studies have been carried out to compare the uptake capacity of different types of moss transplants. However, until now the relationship between the uptake of elements in devitalized moss bags and in irrigated transplants has not been explored. In this study, the final concentrations of Cd, Cu, Hg, Pb and Zn were determined in irrigated and devitalized moss transplants in the surroundings of a steelworks. The concentrations were also compared with those of the same elements in the bulk deposition to determine which type of moss transplant yields the closest correlations. Devitalized moss retained higher concentrations of all of the elements (except Hg) than the irrigated moss. Both irrigated and devitalized moss transplants appear to detect the same type of contamination (i.e. particulate matter and dissolved metals rather than gaseous forms) as significant correlations were found for Cu, Hg, Pb and Zn, whereas, neither type of the moss transplant was sensitive enough to detect changes in the soluble fraction load of bulk deposition. Further studies will be needed to a better understanding of the correlation between the concentrations of elements in moss transplants with the particulate fraction of the bulk deposition. This will enable the establishment of a more robust and accurate biomonitoring tool.

What potential do mosses have as biomonitors of POPs? A comparative study of hexachlorocyclohexane sorption.

Persistent organic pollutants (POPs) pose a significant global threat to human health and the environment, and require continuous monitoring due to their ability to migrate long distances. Active biomonitoring using cloned mosses is an inexpensive but underexplored method to assess POPs, mainly due to the poor understanding of the loading mechanisms of these pollutants in mosses. In this work, Fontinalis antipyretica (aquatic moss) and Sphagnum palustre (terrestrial moss) were evaluated as potential biomonitors of hexachlorocyclohexanes (HCHs: α-, ß-, γ-, δ-HCH), crucial POPs. Moss clones, grown in photobioreactors and subsequently oven-dried, were used. Their lipid composition and distribution were characterized through molecular and histochemical studies. Adsorption experiments were carried out in the aqueous phase using the repeated additions method and in the gas phase using an active air sampling technique based on solid-phase extraction, a pioneering approach in moss research. F. antipyretica exhibited greater lipid content in the walls of most cells and higher adsorption capacity for all HCH isomers in both gaseous and liquid environments. These findings highlight the need for further investigation of POP loading mechanisms in mosses and open the door to explore other species based on their lipid content.

On the use of epigaeic mosses to biomonitor atmospheric deposition of nitrogen.

In this study, we investigated whether the terrestrial moss Pseudoscleropodium purum can be used to biomonitor atmospheric deposition of nitrogen (N). For this purpose, we first determined whether there are any interspecific differences in the concentrations of total N and δ(15)N between the two species of terrestrial moss most commonly used in biomonitoring studies, P. purum and Hypnum cupressiforme. Second, we determined the spatial distribution of N and δ(15)N at small and large scales: (1) by analysis of 165 samples from the surroundings of an aluminium smelter and (2) by analysis of 149 samples from sites forming part of a regular 15 × 15-km sampling network in Galicia (northwest Spain). We did not find any interspecific differences in either total N or δ(15)N. Analysis of δ(15)N enabled us to identify large-scale spatial patterns of distribution that were congruent with the location of the main N emission sources (unlike the analysis of total N). However, we did not identify any such patterns for the small-scale source of N emission studied. The results show that analysis of δ(15)N has an advantage compared with the analysis of total N in that it provides information about the source of N rather than about the amount of N received. Furthermore, isotope discrimination appears to occur, with the bryophytes preferentially accumulating the N(14) isotope. Although this amplifies the signal of reduced forms, it is not problematical for determining spatial-distribution patterns.

Establishing reference values of spectral reflectance indices in transplants of Pseudoscleropodium purum for potential use in atmospheric biomonitoring.

We studied the spatiotemporal variation of the photochemical reflectance index (PRI) and the chlorophyll content index (CHL index) in a terrestrial moss, using self-watering transplants distributed in 8 sampling sites that were sampled periodically during up to 4 years. We did not detect any seasonal patterns or difference between the studied sites, and therefore the variation across the sites reflected the influence of environmental variables in the area. We established the reference thresholds associated with physiological stress as -0.212 for PRI and 1.195 for CHL index. Our findings could be applied for biomonitoring atmospheric contamination on the basis of the physiological stress shown by the moss used.

Global decrease in heavy metal concentrations in brown algae in the last 90 years.

In the current scenario of global change, heavy metal pollution is of major concern because of its associated toxic effects and the persistence of these pollutants in the environment. This study is the first to evaluate the changes in heavy metal concentrations worldwide in brown algae over the last 90 years (>15,700 data across the globe reported from 1933 to 2020). The study findings revealed significant decreases in the concentrations of Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb and Zn of around 60-84% (ca. 2% annual) in brown algae tissues. The decreases were consistent across the different families considered (Dictyotaceae, Fucaceae, Laminariaceae, Sargassaceae and Others), and began between 1970 and 1990. In addition, strong relationships between these trends and pH, SST and heat content were detected. Although the observed metal declines could be partially explained by these strong correlations, or by adaptions in the algae, other evidences suggest an actual reduction in metal concentrations in oceans because of the implementation of environmental policies. In any case, this study shows a reduction in metal concentrations in brown algae over the last 50 years, which is important in itself, as brown algae form the basis of many marine food webs and are therefore potential distributors of pollutants.

Unravelling the metal uptake process in mosses: Comparison of aquatic and terrestrial species as air pollution biomonitors.

Transplanted mosses have been widely shown to be excellent tools for biomonitoring air pollution; however, it is not clear how the functional groups present on their surfaces affect the uptake of metal cations. In the present study, we examined differences in trace metal accumulation in two terrestrial and one aquatic moss species, and investigated whether the differences depended on their physico-chemical characteristics. In the laboratory, we determined C, N and H contents in their tissues and obtained the ATR-FTIR spectra (to identify the presence of functional groups). We also conducted surface acid-base titrations and metal adsorption assays with Cd, Cu and Pb. In the field, we exposed transplants of each species near different air-polluting industries, and determined the mosses enrichment of Al, Cd, Co, Cr, Cu, Fe, Ni, Pb and V. Laboratory results demonstrated higher metal uptake capacity in the terrestrial mosses Sphagnum palustre and Pseudoscleropodium purum, compared to that in the aquatic moss Fontinalis antipyretica, which can be attributed to a greater abundance of acidic functional groups (i.e. negatively charged binding sites) on the surface of the terrestrial mosses. The affinity of moss for certain elements depends on the abundance and nature of surface functional groups. Accordingly, the metal concentrations generally reached higher levels in S. palustre transplants compared to the other species, except for the uptake of Hg, which was higher in F. antipyretica. However, the findings also suggest an interaction between the type of environment (terrestrial or aquatic) and the moss characteristics that may influence the abovementioned trend. Thus, irrespective of the physico-chemical characteristics, metal uptake varied depending on the environment of origin of the mosses "i.e. atmospheric or aquatic". In other words, the findings suggest that species that accumulate more metals in terrestrial environments will accumulate lower amounts of metals in aquatic environments and vice versa.

Trends of asthma mortality in Galicia from 1993 to 2007.

INTRODUCTION: In the past few years, deaths due to asthma appear to decrease at least in Western countries; but there are significant variations between populations. The aim of this study is to describe the trends in deaths due to asthma between 1993 and 2007 in our community and to analyze any factors associated with this. METHODS: All cases, which had asthma as a cause of death, were included in the study. The mortality data were obtained from the official death certificate from the Deaths Register. Mortality relative risk, based on the calendar year, sociodemographic variables (age and gender), seasons, and days of the week, were estimated using a Poisson generalized linear model with a log-link. RESULTS: In the 15 years of the study period, a total of 1180 people had died due to asthma, mainly in winter (34.5%), women (64.5%), and advanced age (65 years or above; 84.6%). A tendency of decreased mortality in all age groups was observed during the period of the study, which was significant in both the sexes in the 35- to 64-year-old age group, and in males above 65 years. CONCLUSION: Death due to asthma is changing favorably in our community, with a tendency to decrease in the past few years. Advanced age, being female, and the winter period are associated with a higher mortality rate due to asthma.

Use of raptors for biomonitoring of heavy metals: gender, age and tissue selection.

The concentrations of cadmium, mercury and lead were determined in liver, kidney and feathers of Accipiter gentilis, Buteo buteo and Strix aluco. No significant differences in the concentrations of metals were observed in relation to either age or gender. Cadmium levels in feathers and in kidney were significantly correlated (p < 0.01 or p < 0.05) in all species. In B. buteo, cadmium concentrations in feathers and in liver were also correlated (p < 0.01), as were the concentrations of lead in feathers and in liver (p < 0.05). The low correlation coefficients let to reject the possibility of predicting metals concentrations in viscera from the concentrations in feathers.

Analysis of intra-thallus and temporal variability of trace elements and nitrogen in Fucus vesiculosus: Sampling protocol optimization for biomonitoring.

To advance the methodological standardization of the biomonitoring technique using macroalgae, we comprehensively characterized the intra-thallus and temporal patterns of variation in concentrations of a wide set of elements (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Zn, N) and δ15N signal in 6 consecutive Fucus vesiculosus apical dichotomous sections collected monthly over a four-year period (2015-2019) at 3 sites on the NW coast of Spain. The concentrations of Al, Co, Fe, Ni, Pb and Zn increased significantly from the youngest to the oldest dichotomies regardless of the sampling time and collection site; As, Cd, N and δ15N showed the opposite trend. Time series analysis revealed a significant and consistent seasonal variation of As, Cd, Co, Cu, Fe, Hg, Ni, Zn, N and δ15N concentrations, with maximum values in winter and minimum values in summer. We discussed the possible mechanisms driving these two sources of variation, and proposed an efficient and effective sampling strategy to minimize their impact in the results of biomonitoring studies, in which the part of the algal thallus selected for chemical analysis and the sampling frequency were carefully considered. This protocol will improve the conclusions and comparability of biomonitoring data from coastal environments.

Testing differences in methods of preparing moss samples. Effect of washing on Pseudoscleropodium purum.

When terrestrial mosses are used to study the risks associated with the accumulation of airborne pollutants, samples must be washed to remove deposits adhering to the surface. Here, we studied the effects of washing the samples as well as of freezing, drying, and acclimatization treatments. The differences between the concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, K, Ni, Pb, Se, V, and Zn in washed and unwashed samples were significant, and therefore, it would not be valid to combine or compare the data corresponding to samples treated thus. We also investigated whether there were significant differences in the concentrations of various metals and metalloids yielded from samples subjected to different treatments prior to washing (freezing, drying, acclimatization after drying, and acclimatization only), while also considering possible effects of the level and type of contamination and the weather conditions. For many of the elements, we found significant differences that depended on both the levels of contamination at each sampling site and the weather. As these differences may be due to changes in the contents of the different cellular fractions, the sequential elution technique was applied to determine the locations of Cu, K, and Zn. The freezing and drying procedures were rejected because they alter the permeability of the membranes and lead to underestimation of the concentrations of elements. With the acclimatization procedure, particles of some elements adhere to the surface, making this option unsuitable when a description of bioconcentration is required. Taking into account these limitations and the lack of an optimal procedure, acclimatization after drying is proposed as the best option for harmonizing the method.

Optimal number of Fucus vesiculosus samples to differentiate between sites affected by distinct levels of heavy metal contamination.

The presence of trace elements in marine habitats is a serious environmental problem which increasingly affects ecosystem and human health. The use of macroalgae as contamination biomonitors represents a valuable alternative approach to traditional physicochemical methods. The present study was carried out to determine the optimal number of samples of Fucus vesiculosus needed to detect statistically significant differences in the mean concentrations of Al, As, Cd, Co Cr, Cu, Fe, Hg, Ni, Pb, Zn, N and δ15N between two sampling sites affected by different levels of contamination. For this purpose, we plotted the density distributions of the concentrations of the different elements and examined the local variability at three sites. For sites with mean concentrations differing by more than 30 %, 20 samples were sufficient to detect significant differences for all of the elements, except Cr. The proposed methodology could be used in other studies in the absence of specific research on each species and region.

Matching times: Trying to improve the correlation between heavy metal levels in mosses and bulk deposition.

The relationship between the concentrations of metals in moss tissues and atmospheric deposition is highly complex, resulting in a general lack of correlations between these two matrices. Here, we tried to improve the significance of the moss-bulk deposition (BD) relationship by eliminating the mismatch between the time that the moss tissue selected for analysis is exposed to atmospheric deposition, and the time during which BD is collected. For this, we analysed the concentrations of Cd, Hg and Pb in new grown tissue of Pseudoscleropodium purum and BD collected monthly, for one year, in 21 sampling sites (SS) under different degrees of pollution. Additionally, we assessed how different moss tissues, including native moss (green parts and new grown tissues of P. purum) and moss transplants of Sphagnum denticulatum, reflect BD to find out which moss tissues provide a better estimate of the atmospheric deposition of heavy metals. First of all, our results showed that eliminating the mismatch between native moss exposure time and BD collection period is not enough to improve their correlation. Environmental variation emerged as the main driver of tissue content variation altering the moss-BD relationship unpredictably. Secondly, native P. purum represents BD values better than devitalized transplants by displaying a greater number of significant correlations with BD. Specifically, green parts of P. purum generally represent better BD than new grown tissues. Overall, we conclude that neither native mosses nor transplants are good estimators of atmospheric heavy metal deposition rates. However, they are good qualitative indicators of the atmospheric deposition, by allowing us to differentiate SS subject to a wide range of pollution levels. Additionally, green parts of P. purum, and likely of other mosses with similar growth forms, should be used in passive biomonitoring studies to make results from different studies comparable.

Methodological advances to biomonitor water quality with transplanted aquatic mosses.

The active biomonitoring technique has been demonstrated to be an excellent tool for monitoring water quality; however, further improvement of the protocol is urgently needed. The present study was carried out to determine the best options for various methodological aspects of monitoring some metals and metalloids (i.e. Al, As, Cd, Co, Cu, Fe, Hg, Ni, Zn and Pb): i) the type of transplant, ii) pre-exposure washing (with or without cellular extractants), iii) the ratio between moss weight and bag surface area, and iv) the depth at which the bags are exposed. The importance of the different methodological aspects in the outcome of biomonitoring studies was also assessed by considering the results of the present and other previously published studies. Regarding the type of transplant, the traditionally used net bags were the best option for enclosing the moss; in addition, washing the moss with extracellular extractants (i.e. EDTA) prior to exposure increased the sensitivity of the technique and reduced the required exposure time (i.e. one week). For the amount of moss packed in each bag, a ratio of 12.5 mg cm-2 was the best choice. Finally, the depth at which the transplants were exposed did not affect pollutant accumulation (in shallow rivers, reservoirs or dams). Pollutant concentrations were also not affected by the existence of thermocline in deep waters during warmer months. Different methodological aspects involved in applying this technique determine the final concentrations of metals in moss. Although the influence of those was variable, for most elements (i.e. As, Cd, Co, Cu, Hg, Pb, Zn) 80% of the total variance was explained by 3-4 aspects, being species selection, devitalization treatment, duration of exposure, and number of transplants exposed the most important.

Can proteomics contribute to biomonitoring of aquatic pollution? A critical review.

Aquatic pollution is one of the greatest environmental problems, and therefore its control represents one of the major challenges in this century. In recent years, proteomics has emerged as a powerful tool for searching protein biomarkers in the field of pollution biomonitoring. For biomonitoring marine contamination, there is a consensus that bivalves are preferred organisms to assess organic and inorganic pollutants. Thus, the bivalve proteome was intensively studied, particularly the mussel. It is well documented that heavy metal pollution and organic chemicals altered the structural proteins causing degradation of tissues of molluscs. Also, it is well known that proteins involved in stress oxidative such as glutathione and enzymes as catalase, superoxide dismutase or peroxisomes are overexpressed in response to contaminants. Additionally, using bivalves, other groups of proteins proposed as pollution biomarkers are the metabolic proteins. Even though other marine species are used to monitor the pollution, the presence of proteomic tools in these studies is scarce. Concerning freshwater pollution field, a great variety of animal species (fish and crustaceans) are used as biomonitors in proteomics studies compared to plants that are scarcely analysed. In fish species, proteins involved in stress oxidative such as heat shock family or proteins from lipid and carbohydrate metabolism were proposed as candidate biomarkers. On the contrary, for crustaceans there is a lack of proteomic studies individually assessing the contaminants. Novel scenarios, including emerging contaminants and new threats, will require proteomic technology for a systematic search of protein biomarkers and a greater knowledge at molecular level of those cellular pathways induced by contamination.

Testing a novel biotechnological passive sampler for monitoring atmospheric PAH pollution.

In this study we evaluated a new type of passive air sampler, the "mossphere" device, filled with a Sphagnum palustre clone. For this purpose, we compared the atmospheric levels of polyaromatic hydrocarbons (PAHs) collected using this device and those collected in conventional bulk deposition and particulate matter (PM10) samplers. All three types of samplers were exposed at 10 sites affected by different levels of pollution and located in two different climate zones. The bulk deposition/ mossphere comparison yielded a greater number of significant regressions with higher coefficients of determination than the PM10/ mossphere comparison. No significant regressions were observed for 3-ring PAHs in either comparison. The mosspheres explain ca. 50% of the variability of the concentrations of 4-, 5- and 6-ring PAHs and total PAHs detected in PM10 and ca. 70% of the corresponding concentrations detected in the bulk deposition. The use of the Sphagnum clone enables standardization of the set-up, thus making the mossphere device a good sampling tool for monitoring 4-, 5- and 6-ring and total PAHs, especially those associated with bulk deposition. The findings indicate the potential usefulness of this innovative technology for mapping PAH levels.

Risk-adjusted early invasive strategy in patients with non-ST-segment elevation acute coronary syndrome in Intensive Cardiac Care Units. / Estrategia invasiva precoz ajustada al riesgo en pacientes con síndrome coronario agudo sin elevación de segmento ST en Unidades de Cuidados Intensivos Cardiológicos.

OBJECTIVE: Current guidelines recommend a risk-adjusted early invasive strategy (EIS) in patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). The present study assesses the application if this strategy, the conditioning factors and prognostic impact upon patients with NSTEACS admitted to Intensive Cardiac Care Units (ICCU). DESIGN: A prospective cohort study was carried out. SETTING: The ICCUs of 8 hospitals in Catalonia (Spain). PATIENTS: Consecutive patients with NSTEACS between October 2017 and March 2018. The risk profile was defined by the European Society of Cardiology criteria. INTERVENTIONS: EIS was defined as the performance of coronary angiography within the first 6hours in patients at very high-risk or within 24hours in high-risk patients. OUTCOME VARIABLES: Mortality or readmission at 6 months. RESULTS: A total of 629 patients were included (mean age 66.6 years), of whom 225 (35.9%) were at very high risk, and 392 (62.6%) at high risk. Most patients (96.2%) underwent an invasive strategy. EIS was performed in 284 patients (45.6%), especially younger patients with fewer comorbidities. These patients had a shorter ICCU and hospital stay, as well as a lesser incidence of ACS, revascularization and death or readmission at 6 months. After adjusting for confounders, the association between EIS and death or readmission at 6 months remained significant (hazard ratio: .66, 95% confidence interval .45-.97; P=.035). CONCLUSIONS: The EIS was performed in a minority of NSTEACS admitted to ICCU, being associated with better outcomes.

Impact of Diabetes Mellitus and Frailty on Long-Term Outcomes in Elderly Patients with Acute Coronary Syndromes.

OBJECTIVES: Diabetes mellitus (DM) and frailty are common in older patients with acute coronary syndromes (ACS). No data exists about its prognostic impact on long-term outcomes and their possible interaction in this setting. DESIGN: Observational prospective study. SETTING: Multicenter registry conducted in 44 hospitals in Spain. PARTICIPANTS: Consecutive patients with ACS aged 80≥years. MEASUREMENTS: A comprehensive geriatric evaluation was performed during hospitalization, including frailty assessment by the FRAIL score. The impact of DM and frailty on the incidence of mortality/readmission at 24 months was analysed by a Cox regression model. RESULTS: A total of 498 patients were included (mean age 84.3 years). Prevalence of previous DM was 199/498 (40.0%). The rate of frail patients was 135/498 (27.1%). The incidence of mortality/readmission was higher frail patients (HR 2.49) (both p<0.001). In contrast, DM was not significantly associated to a higher rate of outcomes (HR 1.23, p=0.060) in the whole cohort. Among non-frail patients, patients with DM had a similar incidence of mortality or readmission (p=0.959). In contrast, among frail patients, DM was significantly associated with a higher incidence of events (HR 1.51, p=0.034). CONCLUSIONS: Unlike frailty status, DM was not associated to poorer long-term outcome in elderly patients with ACS. Among frail patients the presence of DM seems to provide additional prognostic information.

Biomonitoring freshwater FISH farms by measuring nitrogen concentrations and the δ15N signal in living and devitalized moss transplants.

The trophic balance of freshwater aquaculture activities has traditionally been monitored by chemical analysis of water; however, the parameters measured are usually characterized by high temporal variability. Aquatic mosses can be used as biomonitors as they integrate both continuous and episodic contamination events. Here we report, for the first time, a method for monitoring N enrichment in the surroundings of fish farms by measuring the N content and isotopic signal (δ15N) of transplanted living and devitalized specimens of the aquatic moss Fontinalis antipyretica. For this purpose, moss samples ("moss bags") were exposed at increasing distances (10, 100, 300 and 1000 m) up- and downstream of the effluent discharge points of four trout farms, for 10 and 30 days. The low natural (background) variability in δ15N in upstream samples enabled detection of outlier values, caused by aquaculture discharges, at distances of 10 and 100 m downstream, especially in devitalized moss and after 10 days of exposure. However, the unexpectedly low N contents of moss samples exposed close to the discharge points complicates interpretation of the high levels of N forms detected by conventional physicochemical analysis of water. Although the mechanisms that modify N parameters in moss tissues were not clear, measurement of the isotopic signal δ15N in devitalized moss exposed for 10 days proved useful for monitoring the N pollution associated with intensive freshwater aquaculture.

Application of macroalgae analysis to assess the natural variability in selected pollution concentrations (N and Hg), and to detect sources of it in coastal environments.

Here we present a new method in which algae are used to detect sources of heavy metal and organic pollution in coastal areas. The procedure involves characterization of the natural range of concentrations of the elements in areas not affected by local sources of pollution and subsequent comparison of concentrations in the study site to these natural range levels. To develop the method, the concentrations of various elements were determined in specimens of the macroalgae Fucus vesiculosus collected at >150 sampling sites along the shoreline. The natural variability in the element concentrations in these zones was established by determining the differences in the tissue concentrations of the elements between pairs of samples separated by different distances. The method was then tested in the surroundings of possible sources of nitrogen and was found to be a tool for detecting sources of small scale nitrogen contamination and for monitoring and evaluating water quality.