Using single-species and algal communities to determine long-term adverse effects of silver nanoparticles on freshwater phytoplankton.

The physical and chemical properties of silver nanoparticles (AgNPs) have led to their increasing use in various fields such as medicine, food, and industry. Evidence has proven that AgNPs cause adverse effects in aquatic ecosystems, especially when the release of Ag is prolonged in time. Several studies have shown short-term adverse effects of AgNPs on freshwater phytoplankton, but few studies have analysed the impact of long-term exposures on these populations. Our studies were carried out to assess the effects of AgNPs on growth rate, photosynthesis activity, and reactive oxygen species (ROS) generation on the freshwater green algae Scenedesmus armatus and the cyanobacteria Microcystis aeruginosa, and additionally on microcystin (MC-LR) generation from these cyanobacteria. The tests were conducted both in single-species cultures and in phytoplanktonic communities exposed to 1 ngL-1 AgNPs for 28 days. The results showed that cell growth rate of both single-species cultures decreased significantly at the beginning and progressively reached control-like values at 28 days post-exposure. This effect was similar for the community-cultured cyanobacteria, but not for the green algae, which maintained a sustained decrease in growth rate. While gross photosynthesis (Pg) increased in both strains exposed in single cultures, dark respiration (R) and net photosynthesis (Pn) decreased in S. armatus and M. aeruginosa, respectively. These effects were mitigated when both strains were exposed under community culture conditions. Similarly, the ROS generation shown by both strains exposed in single-species cultures was mitigated when exposure occurred in community cultures. MC-LR production and release were significantly decreased in both single-species and community exposures. These results can supply helpful information to further investigate the potential risks of AgNPs and ultimately help policymakers make better-informed decisions about their utilization for environmental restoration.

Site percolation threshold of composite square lattices and its agroecology applications.

We analyze the percolation threshold of square lattices comprising a combination of sites with regular and extended neighborhoods. We found that the percolation threshold of these composed systems smoothly decreases with the fraction of sites with extended neighbors. This behavior can be well-fitted by a Tsallis q-Exponential function. We found a relation between the fitting parameters and the differences in the gyration radius among neighborhoods. We also compared the percolation threshold with the critical susceptibility of nearest and next-to-nearest neighbor monoculture plantations vulnerable to the spread of phytopathogen. Notably, the critical susceptibility in monoculture plantations can be described as a linear combination of two composite systems. These results allow the refinement of mathematical models of phytopathogen propagation in agroecology. In turn, this improvement facilitates the implementation of more efficient computational simulations of agricultural epidemiology that are instrumental in testing and formulating control strategies.

Adverse effects of iron-based nanoparticles on freshwater phytoplankton Scenedesmus armatus and Microcystis aeruginosa strains.

Zero-valent nano-iron particles (nZVI) are increasingly present in freshwater aquatic environments due to their numerous applications in environmental remediation. However, despite the broad benefits associated with the use and development of nZVI nanoparticles, the potential risks of introducing them into the aquatic environment need to be considered. Special attention should be focused on primary producer organisms, the basal trophic level, whose impact affects the rest of the food web. Although there are numerous acute studies on the acute effects of these nanoparticles on photosynthetic primary producers, few studies focus on long-term exposures. The present study aimed at assessing the effects of nZVI on growth rate, photosynthesis activity, and reactive oxygen activity (ROS) on the freshwater green algae Scenedesmus armatus and the cyanobacteria Microcystis aeruginosa. Moreover, microcystin production was also evaluated. These parameters were assessed on both organisms singly exposed to 72 h-effective nZVI concentration for 10% maximal response for 28 days. The results showed that the cell growth rate of S. armatus was initially significantly altered and progressively reached control-like values at 28 days post-exposure, while M. aeruginosa did not show any significant difference concerning control values at any time. In both strains dark respiration (R) increased, unlike net photosynthesis (Pn), while gross photosynthesis (Pg) only slightly increased at 7 days of exposure and then became equal to control values at 28 days of exposure. The nZVI nanoparticles generated ROS progressively during the 28 days of exposure in both strains, although their formation was significantly higher on green algae than on cyanobacteria. These data can provide additional information to further investigate the potential risks of nZVI and ultimately help decision-makers make better informed decisions regarding the use of nZVI for environmental remediation.

Intranasal disulfiram-induced encephalopathy: clinical and neuroimage findings. / Encefalopatía inducida por disulfiram intranasal: resultados clínicos y de neuroimagen.

INTRODUCTION: Disulfiram-induced-encephalopathy is a rare complication that has been well described in adults. Although it usually occurs in acute intoxication with high doses of disulfiram, late onset encephalopathy has also been reported. Some authors propose the inhibition of dopamine beta-hydroxylase mediated by toxic metabolites of disulfiram as the main responsible, but the exact mechanism remains unclear. The aim of this report was to describe the clinical and neuroimaging findings in an unusual case of acute encephalitis due to disulfiram toxicity associated to chronic intranasal consume. CASE REPORT: A chronic alcoholic who referred snorted use of a very high dose of disulfiram without simultaneous alcohol intake developed an acute encephalopathy with a rapidly progressive respiratory failure. A characteristic neuroimage finding consisting in extensive bilateral symmetric involvement of both pallidal nuclei was described. Recovery and neurologic improvement were slow. Two months after the intoxication, the patient still had slight intentional tremor and a scheduled magnetic resonance imaging. showed evolution of symmetrical areas of cytotoxic edema to necrosis. CONCLUSION: Disulfiram-induced neurotoxicity must be suspect during chronic therapy with disulfiram or after acute ingestion of high doses. Symptoms such as symmetric sensory and motor neuropathy, confusion, catatonia, parkinsonism, ataxia, choreoathetosis, seizures and encephalopathy should make us rule out this disorder. A brain imaging test should be performed in these patients since a characteristic involvement of both nuclei pallidus has been described, but it is not present in all patients.

TITLE: Encefalopatía inducida por disulfiram intranasal: resultados clínicos y de neuroimagen.Introducción. La encefalopatía inducida por disulfiram es una complicación rara que se ha descrito en adultos, generalmente en intoxicaciones agudas, aunque también se ha comunicado en forma de encefalopatía de aparición tardía. Su mecanismo fisiopatológico se desconoce con exactitud, pero se atribuye a un posible papel en la inhibición de la dopamina beta-hidroxilasa mediada por metabolitos tóxicos del disulfiram. El objetivo de este trabajo fue describir los hallazgos clínicos y en la neuroimagen en un caso inusual de encefalopatía aguda tóxica inducida por un consumo intranasal crónico de disulfiram. Caso clínico. Paciente de 48 años con enolismo crónico que refirió el uso inhalado por vía intranasal de una dosis muy elevada de disulfiram sin ingesta simultánea de alcohol desarrolló una encefalopatía aguda con insuficiencia respiratoria rápidamente progresiva. La neuroimagen reveló una extensa afectación simétrica bilateral de ambos núcleos pálidos, un hallazgo característico en esta intoxicación. La recuperación neurológica fue lenta. Dos meses después de la intoxicación, el paciente presentaba un ligero temblor intencional residual y una resonancia magnética mostró una evolución de las áreas simétricas de edema citotóxico a necrosis. Conclusión. La neurotoxicidad inducida por disulfiram debe sospecharse durante el tratamiento crónico con disulfiram o después de una ingesta aguda de dosis elevadas. La presencia de síntomas como una neuropatía sensitivomotora simétrica, confusión, catatonía, parkinsonismo, ataxia, coreoatetosis, convulsiones y encefalopatía nos debe obligar a descartar este trastorno. La neuroimagen debe considerarse en este escenario, ya que se ha descrito una afectación característica de ambos núcleos pálidos.

[Quality of life after a social-physical activity community intervention in elderly people with social risk. Clinical trial]. / Calidad de vida tras una intervención comunitaria sociomotriz en mayores con riesgo social. Ensayo clínico.

OBJECTIVE: To assess the effectiveness of a social-physical activity program to improve the health-related quality of life of patients over 65years old with social risk. MATERIAL AND METHODS: Randomized clinical trial. SETTING: Community; primary care and public schools. SUBJECTS: patients over 65years old with social risk, who went to the health center during the study period and met the inclusion criteria, n=102. INTERVENTIONS: Subjects were randomized into two groups. The intervention group conducted two weekly sessions of 1hour of physical exercise, for 4months; monthly sessions on healthy habits and three days of social activities. The control group received the usual advice. Quality of life was assessed using the SF-36 questionnaire; previously and at the end of the program. RESULTS: The study was completed by 80 subjects (mean age 71.5±5 years; 91.3% women). Baseline, there were no significant differences between groups, and their standardized physical and mental summary components of the SF-36 were below the population reference values (P<.01). After the program, the intervention group improved significantly, compared to the control group, in the 8 scales of the SF-36 and in the summary components, with a greater increase of 4points (P<.01) in the physical component, and 10 points in the mental component (p<0.01). CONCLUSIONS: The community program of social-physical activity intervention improves the health-related quality of life in older people at social risk.

Percolation-intercropping strategies to prevent dissemination of phytopathogens on plantations.

Phytophthora is one of the most aggressive and worldwide extended phytopathogens that attack plants and trees. Its effects produce tremendous economical losses in agronomy and forestry since no effective fungicide exists. We propose to combine percolation theory with an intercropping sowing configuration as a non-chemical strategy to minimize the dissemination of the pathogen. In this work, we model a plantation as a square lattice where two types of plants are arranged in alternating columns or diagonals, and Phytophthora zoospores are allowed to propagate to the nearest and next-to-nearest neighboring plants. We determine the percolation threshold for each intercropping configuration as a function of the plant's susceptibilities and the number of inoculated cells at the beginning of the propagation process. The results are presented as phase diagrams where crop densities that prevent the formation of a spanning cluster of susceptible or diseased plants are indicated. The main result is the existence of susceptibility value combinations for which no spanning cluster is formed even if every cell in the plantation is sowed. This finding can be useful in choosing a configuration and density of plants that minimize damages caused by Phytophthora. We illustrate the application of the phase diagrams with the susceptibilities of three plants with a high commercial value.

[Functional physical condition after a multi-component community intervention of active aging: Pragmatic clinical trial]. / Condición física funcional tras una intervención comunitaria multicomponente de envejecimiento activo. Ensayo clínico pragmático.

OBJECTIVE: The objective is to assess the effectiveness of a multicomponent program of active aging in the improvement of the functional physical condition of patients older than 65years old with social risk. MATERIAL AND METHODS: Pragmatic clinical trial non-blinded. SETTING: Community activity; primary care and public education center. PARTICIPANTS: Patients older than 65years and diagnosed with social risk. The patients who attended at the health center and fulfilled the inclusion criteria were selected consecutively (n=102). INTERVENTIONS: The patients were randomized into the intervention group or to the control group. The intervention included two weekly sessions of 1h of exercise during 4months, monthly health education sessions, and three days of social activities. The control group received the regular tips. The physical conditions were evaluated before and at the end the study. RESULTS: Eighty of the patients completed the study. Their middle age was 71.5±5 years old, and 91.3% of them were women. There was no significant differences between both groups. After the intervention, all the test for physical qualities improved in the intervention group; in the 6-minutes walk test the patients improved their mark in a 98% from the baseline marks, with an average increase of 65±35m. Flexibility improved in the 60% of the patients (95%CI: 50-70); strength increased an 84% (95%CI: 76-92), and dynamic balance increased a 79% (95%CI: 70-88). In control group improve some test marks but it had no statistical significance. CONCLUSIONS: The socio-motor intervention program coordinated between health services and educational centers improves the functional physical condition of the elderly with social risk.

Site-bond percolation solution to preventing the propagation of Phytophthora zoospores on plantations.

We propose a strategy based on the site-bond percolation to minimize the propagation of Phytophthora zoospores on plantations, consisting in introducing physical barriers between neighboring plants. Two clustering processes are distinguished: (i) one of cells with the presence of the pathogen, detected on soil analysis, and (ii) that of diseased plants, revealed from a visual inspection of the plantation. The former is well described by the standard site-bond percolation. In the latter, the percolation threshold is fitted by a Tsallis distribution when no barriers are introduced. We provide, for both cases, the formulas for the minimal barrier density to prevent the emergence of the spanning cluster. Though this work is focused on a specific pathogen, the model presented here can also be applied to prevent the spreading of other pathogens that disseminate, by other means, from one plant to the neighboring ones. Finally, the application of this strategy to three types of commercially important Mexican chili plants is also shown.

Optimal reactive power compensation in electrical distribution systems with distributed resources. Review.

In this paper an exhaustive bibliographical revision of the mathematical methods used for the optimal selection and location of reactive power compensating elements is developed, the results obtained by different authors for different objective functions are analyzed and a scientific problem in the conflict that the electric variables show when analyzed individually is identified; thus demonstrating the need to analyze this problem in a multi-criteria way and taking into account topologies of distribution grids with distributed generation and energy storage. This research demonstrates that reactive power compensation in distribution grids with distributed resources is a problem that must be analyzed from multiple criteria that consider several objective functions to be optimized; thus achieving a global solution that contemplates an optimal location and dimensioning of reactive power compensating elements that contribute to the joint improvement of the voltage profiles, minimization of power losses, harmonic mitigation, increased line capacity, voltage stability and power factor improvement, all of them to a minimum investment cost. A theoretical heuristic is also proposed to solve the described problem, based on the multicriteria optimization method.

The Changing Epidemiology of Infective Endocarditis in the Twenty-First Century.

PURPOSE OF THE REVIEW: Infective endocarditis (IE) is a relatively infrequent infectious disease. It does, however, causes serious morbidity, and its mortality rate has remained unchanged at approximately 25%. Changes in IE risk factors have deeply impacted its epidemiology during recent decades but literature from low-income countries is very scarce. Moreover, prophylaxis guidelines have recently changed and the impact on IE incidence is still unknown. RECENT FINDINGS: In high-income countries, the proportion of IE related to prior rheumatic disease has decreased significantly and has been replaced proportionally by cases related to degenerative valvulopathies, prosthetic valves, and cardiovascular implantable electronic devices. Nosocomial and non-nosocomial-acquired cases have risen, as has the proportion caused by staphylococci, and the median age of patients. In low-income countries, in contrast, rheumatic disease remains the main risk factor, and streptococci the most frequent causative agents. Studies performed to evaluate impact of guidelines changes' have shown contradictory results. The increased complexity of cases in high-income countries has led to the creation of IE teams, involving several specialties. New imaging and microbiological techniques may increase sensitivity for diagnosis and detection of IE cases. In low-income countries, IE remained related to classic risk factors. The consequences of prophylaxis guidelines changes are still undetermined.

Efficacy of the nanoparticle-drug conjugate CRLX101 in combination with bevacizumab in metastatic renal cell carcinoma: results of an investigator-initiated phase I-IIa clinical trial.

BACKGROUND: Anti-angiogenic therapies are effective in metastatic renal cell carcinoma (mRCC), but resistance is inevitable. A dual-inhibition strategy focused on hypoxia-inducible factor (HIF) is hypothesized to be active in this refractory setting. CRLX101 is an investigational camptothecin-containing nanoparticle-drug conjugate (NDC), which durably inhibits HIF1α and HIF2α in preclinical models and in gastric cancer patients. Synergy was observed in the preclinical setting when combining this NDC and anti-angiogenic agents, including bevacizumab. PATIENTS AND METHODS: Patients with refractory mRCC were treated every 2 weeks with bevacizumab (10 mg/kg) and escalating doses of CRLX101 (12, 15 mg/m(2)) in a 3 + 3 phase I design. An expansion cohort of 10 patients was treated at the recommended phase II dose (RP2D). Patients were treated until progressive disease or prohibitive toxicity. Adverse events (AEs) were assessed using CTCAE v4.0 and clinical outcome using RECIST v1.1. RESULTS: Twenty-two patients were response-evaluable in an investigator-initiated trial at two academic medical centers. RCC histologies included clear cell (n = 12), papillary (n = 5), chromophobe (n = 2), and unclassified (n = 3). Patients received a median of two prior therapies, with at least one prior vascular endothelial tyrosine kinase inhibitor therapy (VEGF-TKI). No dose-limiting toxicities were observed. Grade ≥3 AEs related to CRLX101 included non-infectious cystitis (5 events), fatigue (3 events), anemia (2 events), diarrhea (2 events), dizziness (2 events), and 7 other individual events. Five of 22 patients (23%) achieved partial responses, including 3 of 12 patients with clear cell histology and 2 of 10 patients (20%) with non-clear cell histology. Twelve of 22 patients (55%) achieved progression-free survival (PFS) of >4 months. CONCLUSIONS: CRLX101 combined with bevacizumab is safe in mRCC. This combination fulfilled the protocol's predefined threshold for further examination with responses and prolonged PFS in a heavily pretreated population. A randomized phase II clinical trial in mRCC of this combination is ongoing.

In vitro antiviral activity against rotavirus and astrovirus infection exerted by substances obtained from Achyrocline bogotensis (Kunth) DC. (Compositae).

BACKGROUND: Achyrocline bogotensis has been traditionally used to treat infections of skin, respiratory, tract urinary and other infections, but not to treat viral gastrointestinal disease. In this study, this Colombian native medicinal plant was investigated by its in vitro anti-rotavirus and anti-astrovirus activity. METHODS: Several extracts and fractions phytochemically obtained from A. bogotensis were evaluated initially for their cell toxicity on MA104 and Caco2 cells and then for their anti-rotavirus (RRV) and anti-astrovirus (Yuc8) activity following three strategies: pre-treatment of cells (blocking effect), direct viral activity (virucidal effect) and post-treatment of infected cells (reduction of viral yield post-infection). In addition qualitative chemical studies were developed for the active compounds. RESULTS: Non-toxic concentrations of a fraction obtained exhibited antiviral activity against both viruses characterized by a virucidal effect and by the reduction of the infectious particles produced post-infection. Steroids, sterols, terpenes, phenols, flavonoids and sesquiterpenlactones were identified qualitatively in the active fraction. CONCLUSIONS: A. bogotensis contains substances with in vitro antiviral activity against rotavirus and astrovirus. This study confirms their anti-microbial properties and describes by the first time its antiviral activity in vitro.

Neandertal roots: Cranial and chronological evidence from Sima de los Huesos.

Seventeen Middle Pleistocene crania from the Sima de los Huesos site (Atapuerca, Spain) are analyzed, including seven new specimens. This sample makes it possible to thoroughly characterize a Middle Pleistocene hominin paleodeme and to address hypotheses about the origin and evolution of the Neandertals. Using a variety of techniques, the hominin-bearing layer could be reassigned to a period around 430,000 years ago. The sample shows a consistent morphological pattern with derived Neandertal features present in the face and anterior vault, many of which are related to the masticatory apparatus. This suggests that facial modification was the first step in the evolution of the Neandertal lineage, pointing to a mosaic pattern of evolution, with different anatomical and functional modules evolving at different rates.

Modulation of immune function by milk fat globule membrane isolates.

The nutritional value and characterization of minor milk components on mammalian immune function are not fully understood. The aim of this research was to test the ability of a milk fat globule membrane (MFGM) isolate to modulate murine immune function in vitro, by studying its effects on splenocyte proliferation, apoptosis, and cytokine production. Proliferation of spleen cells was not affected by the MFGM isolate; however, in the presence of polyclonal activators, the MFGM isolate suppressed cell proliferation. Results obtained by flow cytometry did not support programmed cell death as the cause of the MFGM immune-modulating capacity. A mode of suppression on the splenocyte activation process was suggested from a marked decrease in the production of IFN-γ and tumor necrosis factor-α cytokines, typical indicators of immune cell activation. The effect of MFGM on IL-4 secretion was significantly less than that for the other 2 cytokines. The activity exerted by the MFGM over concanavalin A-stimulated cells differed from that observed in cells treated with lipopolysaccharide, suggesting a different mode of action depending on the activator used. These results indicate the potential of MFGM extracts as functional ingredients with bioactive modulating capacity.

Lactobacillus helveticus: the proteolytic system.

Lactobacillus helveticus is one of the species of lactic acid bacteria (LAB) most commonly used in the production of fermented milk beverages and some types of hard cheese. The versatile nature of this bacterium is based on its highly efficient proteolytic system consisting of cell-envelope proteinases (CEPs), transport system and intracellular peptidases. Besides use of L. helveticus in cheese processing, the production of fermented milk preparations with health promoting properties has become an important industrial application. Studies have shown that fermented dairy products are able to decrease blood pressure, stimulate the immune system, promote calcium absorption, and exert an anti-virulent effect against pathogens. These beneficial effects are produced by a variety of peptides released during the hydrolysis of milk proteins by the proteolytic system of L. helveticus, which provides the bacterium with its nutritional requirements for growth. In recent years, studies have focused on understanding the factors that affect the kinetics of milk protein hydrolysis by specific strains and have concentrated on the effect of pH, temperature, growth phase, and matrix composition on the bacterial enzymatic system. This review focuses on the role of the proteolytic system of L. helveticus in the production of bioactive compounds formed during fermentation of dairy products. Taking advantage of the powerful proteolytic system of this bacterium opens up future opportunities to search for novel food-derived compounds with potential health promoting properties.

[Aortic dissection: 2 cases of atypical presentation]. / Disección aórtica: 2 casos de presentación atípica.

Aortic dissection is an uncommon disease with high mortality. The typical clinical picture is characterised by sudden pain in the retrosternal or interscapular region radiating to the back and abdomen. There can be several signs, depending on the arterial branches involved (stroke, renal or mesenteric ischaemia), and even the absence of pain. Two cases with unusual presentations are discussed; one with sudden paresis and ischaemia of both legs with involvement of spinal and iliac branches, and the other began as a syncope and right hemiparesis with carotid involvement.

Bovine milk fat globule membrane affects virulence expression in Escherichia coli O157:H7.

The aim of this study was to examine the effect of the bovine milk fat globule membrane (MFGM) on the virulence of Escherichia coli O157:H7. The MFGM was extracted from raw or heat-treated milk, resulting in 2 preparations differing in protein composition. Both heated and raw MFGM exerted an inhibitory effect on Shiga toxin gene expression by E. coli O157:H7 (ratios of -7.69 and -5.96, respectively). Interestingly, the effect was stronger with heated MFGM, with a larger decrease in expression of the virulence gene fliC (ratio of -9.43). The difference in effect observed between heated and raw MFGM could be explained by the difference in protein composition between the 2 preparations. These results show, for the first time, a specific effect of MFGM on expressionof Shiga toxin genes as well as genes involved in the motility of E. coli O157:H7. This may offer a new approach to mitigate the adverse health effects caused by E. coli O157:H7 infections.

[Effectiveness of a social-physical activity intervention program in an elderly social risk population]. / Efectividad de un programa de intervención socio-motriz en población mayor con riesgo social.

INTRODUCTION: The objective is to assess the effectiveness of a social-physical activity intervention program in the improvement of the health-related quality of life and functional physical condition of patients older than 65 years at social risk. MATERIAL AND METHODS: Quasi-experimental intervention (pretest-posttest). SETTING: Community activity; primary care and public education centres. PARTICIPANTS: Twenty-nine patients older than 65 years, seen at the health centre, with a diagnosis of social risk. The program included monthly health education sessions and two weekly sessions of one hour of exercise for 6 months. Measurements were taken before and at the end of the study. Outcome variables were: quality of life valued using the SF36 questionnaire and functional fitness through Senior Fitness Battery Test. RESULTS: After intervention improved all tests for the physical qualities improved after the intervention; in the 6-minutes walk all subjects improved from baseline, with an average increase of 62 +/- 36 metres (95% CI: 48-76). The SF-36 questionnaire improved 8 scales and mental summary component with a further increase of 6 points (P < .05). CONCLUSIONS: Social-physical activity intervention program improved the health-related quality of life related and functional physical condition in older people at social risk. This paper provides evidence in favour of the implementation of social-physical community activities, coordinated between health services and education centres, aimed at the elderly at risk.

Ozonation and reductive deiodination of iopromide to reduce the environmental burden of iodinated X-ray contrast media.

The potential of ozonation for the removal of iodinated X-ray contrast media (ICM) with focus on the oxidation products was examined. Iopromide used as model compound was dissolved in tap water, respectively in the effluent of a membrane bioreactor and was ozonated. Ozone (10 mg/L) was continuously introduced into a semi-batch reactor (35 L/h). After 30 minutes the ozone concentration was increased to 30 mg/L. In all experiments the iopromide concentration decreased very fast, whereas the decrease of the amount of organic bound iodine (AOI) was much lower. The concentration of iodate, the inorganic oxidation product increases with time, depending on the AOI decrease. The data clearly show that the ozonation of iopromide using a common applied ozone dosage leads to the formation of numerous iodinated transformation products, which are detectable by LC-ESI-MS. As an alternative treatment, especially for the treatment of urine or hospital waste water, the source for the contamination, it was tested if iopromide can be deiodinated by zero-valent iron. First experiments done in stirred batch reactors using iopromide dissolved in ultra pure water and urine with an initial pH of 2 showed that iopromide can be deiodinated completely by zero-valent iron. Even in contaminated urine collected in a hospital a deiodination of ICM was possible. Kinetic studies at constant pH showed that the deiodination can be described by pseudo-first order for equal iopromide and iron concentrations. The observed rate constant kobs increased with decreasing pH with a maximum at pH 3 with 4.76x10(-4) s(-1). The concentration of iopromide can be decreased by ozonation and by the reductive dehalogenation. In case of ozonation iodinated organic compounds are the main reaction products, whereas the reductive dehalogenation leads to transformation products which are not iodinated and are thus most probable biodegradable.