Statutory Registration for Health and Social Professionals

The Department of Health and Children has committed itself to introducing legislation to provide for the statutory registration of certain health and social care professionals. Against this background, the Department held a series of workshops with the professional bodies to try to reach a consensus on how a system of statutory registration might operate in practice. The workshops were facilitated by the Institute of Public Administration. This document is the culmination of these workshops and it is now being circulated widely to the members of each profession involved for their consideration. Download the Report here

Speech by Mr Micheál Martin TD at Launch of Pre-Registration Nursing Degree Programme

Good afternoon ladies and gentlemen. I am very pleased that you were all able to accept my invitation to join me here today on this landmark occasion for nursing education. It is fitting that all of the key stakeholders from the health and education sectors should be so well represented at the launch of an historic new development. Rapid and unpredictable change throughout society has been the hallmark of the twenty-first century, and healthcare is no exception. Regardless of what change occurs, no one doubts that nursing is intrinsic to the health of this nation. However, significant changes in nurse education are now needed if the profession is to deliver on its social mandate to promote people´s health by providing excellent and sensitive care. As science, technology and the demands of the public for sophisticated and responsive health care become increasingly complex, it is essential that the foundation of nursing education is redesigned. Pre-registration nursing education has already undergone radical change over the past eight years, during which time it has moved from an apprenticeship model of education and training to a diploma based programme firmly rooted in higher education. The Secretary General of my Department, Michael Kelly, played a leading role in bringing about this transformation, which has greatly enhanced the way students are prepared for entry to the nursing profession. The benefits of the revised model of education are clearly evident from the quality of the nurses graduating from the diploma programme. The Commission on Nursing examined the whole area of nursing education, and set out a very convincing case for educating nursing students to degree level. It argued that nurses of the future would be required to possess increased flexibility and the ability to work autonomously. A degree programme would provide nurses with a theoretical underpinning that would enable them to develop their clinical skills to a greater extent and to respond to future challenges in health care, for the benefit of patients and clients of the health services. The Commission has provided a solid framework for the professional development of nurses and midwives, including a process that is already underway for the creation of clinical nurse specialist and advanced nurse practitioner posts. This process will facilitate the transfer of skills across divisions of nursing. In this scenario, it is clearly desirable that the future benchmark qualification for registration as a nurse should be a degree in nursing studies. A Nursing Education Forum was established in early 1999 to prepare a strategic framework for the implementation of a nursing degree programme. When launching the Forum´s report last January, I indicated that the Government had agreed in principle to the introduction of the proposed degree programme next year. At the time two substantial outstanding issues had yet to be resolved, namely the basis on which nurse teachers would transfer from the health sector to the education sector and the amount of capital and revenue funding required to operate the degree programme. My Department has brokered agreements between the Nursing Alliance and the Higher Education Institutions for the assimilation of nurse teachers as lecturers into their affiliated institutions. The terms of these agreements have been accepted by all four nursing unions following a ballot of their nurse teacher members. I would like to pay particular tribute to all nurse teachers who have contributed to shaping the position, relevance and visibility of nursing through leadership, which embodies scholarship and excellence in the profession of nursing itself. In response to a recommendation of the Nursing Education Forum, I established an Inter-Departmental Steering Committee, chaired by Bernard Carey of my Department, to consider all the funding and policy issues. This Steering Committee includes representatives of the Department of Finance and the Department of Education and Science as well as the Higher Education Authority. The Steering Committee has been engaged in intensive negotiations with representatives of the Conference of Heads of Irish Universities and the Institutes of Technology in relation to their capital and revenue funding requirements. These negotiations were successfully concluded within the past few weeks. The satisfactory resolution of the industrial relations and funding issues cleared the way for me to go to the Government with concrete proposals for the implementation of degree level education for nursing students. I am delighted to announce here today that the Government has approved all of my proposals, and that a four-year undergraduate pre-registration nursing degree programme will be implemented on a nation-wide basis at the start of the next academic year, 2002/2003. The Government has approved the provision of capital funding totalling £176 million pounds for a major building and equipment programme to facilitate the full integration of nursing students into the higher education sector. This programme is due to be completed by September 2004, and will ensure that nursing students are accommodated in purpose built schools of nursing studies with state of the art clinical skills and human science laboratories at thirteen higher education sites throughout the country. The Government has also agreed to make available the substantial additional revenue funding required to support the nursing degree programme. By 2006, the full year cost of operating the programme will rise to some £43 million pounds. The scale of this investment in pre-registration nursing education is enormous by any yardstick. It demonstrates the firm commitment of myself and my Government colleagues to the full implementation of the recommendations of the Commission on Nursing, of which the introduction of pre-registration degree level education is arguably the most important. This historic decision, and it is truly historic, will finally put the education of nurses on a par with the education of other health care professionals. The nursing profession has long been striving for parity, and my own involvement in the achievement of it is a matter of deep personal satisfaction to me. I am also pleased to announce that the Government has approved my plans for increasing the number of nursing training places to coincide with the implementation of the degree programme next year. Ninety-three additional places in mental handicap and psychiatric nursing will be created at Athlone, Letterkenny, Tralee and Waterford Institutes of Technology. This will yield 392 extra places over the four years of the degree programme. A total of 1,640 places annually on the new degree programme will thus be available. This is an all-time record, and maintaining the annual student intake at this level for the foreseeable future is a key element of my overall strategy for ensuring that we produce sufficient “home-grown” nurses for our health services. I am aware that the Nursing Alliance were anxious that some funding would be provided for the further academic career development of nurse teachers who transfer to one of the six Universities that will be involved in the delivery of the degree programme. I am happy to confirm that up to £300,000 in total per year will be available for this purpose over the first four years of the degree programme. In line with a recommendation of the Commission on Nursing, my Department will have responsibility for the administration of the nursing degree budget until the programme has been bedded down in the higher education sector. A primary concern will be to ensure that the substantial capital and revenue funding involved is ring-fenced for nursing studies. It is intended that responsibility for the budget will be transferred to the Department of Education and Science after the first cohort of nursing degree students have graduated in 2006. In the context of today´s launch, it is relevant to refer to a special initiative that I introduced last year to assist registered nurses wishing to undertake part-time nursing degree courses. Under this initiative, nurses are entitled to have their course fees paid by their employers in return for a commitment to continue working in the public health service for a period following completion of the course. This initiative has proved extremely popular with large numbers of nurses availing of it. I want to confirm here today that the free fees initiative will continue in operation until 2005, at a total cost of at least £15 million pounds. I am giving this commitment in order to assure this year´s intake of nursing students to the final diploma programmes that fee support for a part-time nursing degree course will be available to them when they graduate in three years time. The focus of today´s celebration is rightly on the landmark Government decision to implement the nursing degree programme next year. As Minister for Health and Children, and as a former Minister for Education, I also have a particular interest in the educational opportunities available to other health service workers to upgrade their skills. I am pleased to announce that the Government has approved my proposals for the introduction of a sponsorship scheme for suitable, experienced health care assistants who wish to become nurses. This new scheme will commence next year and will be administered by the health boards. Successful applicants will be allowed to retain their existing salaries throughout the four years of the degree programme in return for a commitment to work as nurses for their health service employer for a period of five years following registration. Up to forty sponsorships will be available annually. The new scheme will enable suitable applicants to undertake nursing education and training without suffering financial hardship. The greatest advantage of the scheme will be the retention by the public health service of staff who are supported under it, since they will have had practical experience of working in the service and their own personal commitment to upgrading their skills will be informed by that experience. I am confident that the sponsorship scheme will be warmly welcomed by health service unions representing care assistants as providing an exciting new career development path for their members. Education and health are now the two pillars upon which the profession of nursing rests. We must continue to build bridges, even tunnels where needed to strengthen this partnership. We must all understand partnerships donâ?Tt just happen they are designed and must be worked at. The changes outlined here today are powerful incentives for those in healthcare agencies, academic institutions and regulatory bodies to design revolutionary programmes capable of shaping a critical mass of excellent practitioners. You have an opportunity, greater perhaps than has been granted to any other generation in history to make certain those changes are for the good. Ultimately changes that will make the country a healthier and more equitable place to live. The challenge relates to building a seamless preparatory programme which equally respects both education and practise as an indivisible duo whilst ensuring that high tech does not replace the human touch. This is a special day in the history of the development of the Irish nursing profession, and I would like to thank everybody for their contribution. I want to express my particular appreciation of two people who by this stage are well known to all of you – Bernard Carey of my Department and Siobhán O´Halloran of the National Implementation Committee. Bernard and Siobhán have devoted considerable time and energy to the project on my behalf over the past fourteen months or so. That we are here today celebrating the launch of degree level education is due in no small part to their successful execution of the mandate that I gave them. We live in a rapidly changing world, one in which nursing can no longer rely on systems of the past to guide it through the new millennium. In terms of contemporary healthcare, nursing is no longer just a reciprocal kindness but rather a highly complex set of professional behaviours, which require serious educational investment. Pre-registration nurse education will always need development and redesign to ensure our health care system meets the demands of modern society. Nothing is finite. Today more than ever the health system is dependent on the resourcefulness of nursing. I have no doubt that the new educational landscape painted will ensure that nurses of the future will be increasingly innovative, independent and in demand. The unmistakable message from my Department is that nursing really matters. Thank you.

Circulating filarial antigen in the hydrocele fluid from individuals living in a bancroftian filariasis area - Recife, Brazil: detected by the monoclonal antibody Og4C3-assay

The purpose of this study was to examine the circulating filarial antigen (CFA) detected by the monoclonal antibody (mAb) Og4C3-ELISA in paired samples of serum and hydrocele fluid from 104 men with hydrocele, living in an endemic area of Wuchereria bancrofti. Nocturnal blood specimens were filtered and examined for microfilariae (MF) and ultrasound was used in order to identify the presence of adult worms (the filaria dance sign - FDS) in the lymphatic vessels of the scrotal area. Four groups were selected according to their parasitological status: group I - 71 MF- and FDS-; group II - 21 MF+ and FDS+; group III - 10 MF- and FDS+ and group IV- 2 MF+ and FDS-. CFA was identified simultaneously (fluid and serum) in 11 (15.5%), 21 (100%), 3 (30%), and 1 (50%) in groups I, II, III, and IV, respectively. In despite of high CFA+ level (antigen Og4C3) units/ml, the Geometrical Mean (GM) = 2696) in the sera of these 36/104 paired samples, when compared to the hydrocele fluid, (GM = 1079), showed a very good correlation between the CFA level in the serum and CFA level in the fluid (r = 0.731). CFA level in the serum of the 23 microfilaremics (groups II and IV) was extremely high (GM = 4189) and was correlated with MF density (r = 0.442). These findings report for the first time the potential alternative use of the hydrocele fluid to investigate CFA using the mAb Og4C3-ELISA.

Presence of JC virus-specific CTL in the cerebrospinal fluid of PML patients: rationale for immune-based therapeutic strategies.

OBJECTIVES: There is urgent need of a treatment for progressive multifocal leukoencephalopathy (PML), caused by the polyomavirus JC (JCV). To evaluate the rationale for immunotherapy of PML, we explored whether JCV-specific cytotoxic T lymphocytes (CTL) can penetrate the central nervous system (CNS). In addition, we studied the breadth of their T-cell receptor (TCR) repertoire, and sought to establish a reliable method to expand these cells in vitro. DESIGN AND METHODS: We enrolled 18 patients in this study, including 16 with proven or possible PML (15 HIV-positive and one HIV-negative), and two HIV-positive patients with other neurological diseases. Detection of JCV-specific CTL in the blood and the cerebrospinal fluid was performed by Cr release and tetramer staining assays in 15 patients. RESULTS: Of 11 PML patients with analyzable cerebrospinal fluid (CSF), two had no detectable JCV-specific CTL in the blood and CSF and died 3.7 and 7.2 months later. The nine remaining patients had an inactive course of PML and detectable JCV-specific CTL in the blood. In addition, four of them (44%) also had detectable JCV-specific CTL in the CSF. Both HIV-positive patients with OND had detectable JCV-specific CTL in the blood and one in the CSF. Using tetramer technology, we obtained highly enriched JCV-specific CTL lines that were able to kill target cells presenting JCV peptides. The breadth of the TCR repertoire was CTL epitope dependent. CONCLUSIONS: These results indicate that JCV-specific CTL are present in the CNS of PML patients and pave the way for an immune-based therapeutic approach.

Use of the paired samples (cerebrospinal fluid and serum) in immunodiagnostic of active and inactive human neurocysticercosis

Paired samples of cerebrospinal fluid (CSF) and serum of 30 patients - 10 with active, 10 with inactive neurocysticercosis (NCC), and 10 control subjects - were evaluated by enzyme-linked immunosorbent assay (ELISA) using two Taenia crassiceps metacestode extracts as antigen in order to detect IgG antibodies. In active NCC, high levels of IgG were detected (p < 0.05). The CSF samples showed 80% (CI 72-88) of reactivity in the saline extract (S) and 90% (CI 84-95) in sodium dodecyl sulphate (SDS) and the serum samples were reactive in 90% (CI 84-95) and 100% (CI 98-100) in the S and SDS antigenic extracts, respectively. The use of the paired samples of CSF and serum in active NCC showed equivalent results suggesting that the serum samples could be used as a screening in those patients whose CSF puncture is counter-indicated.

Fluid flow regulates stromal cell organization and CCL21 expression in a tissue-engineered lymph node microenvironment.

In the paracortex of the lymph node (LN), T zone fibroblastic reticular cells (TRCs) orchestrate an immune response by guiding lymphocyte migration both physically, by creating three-dimensional (3D) cell networks, and chemically, by secreting the chemokines CCL19 and CCL21 that direct interactions between CCR7-expressing cells, including mature dendritic cells and naive T cells. TRCs also enwrap matrix-based conduits that transport fluid from the subcapsular sinus to high endothelial venules, and fluid flow through the draining LN rapidly increases upon tissue injury or inflammation. To determine whether fluid flow affects TRC organization or function within a 3D network, we regenerated the 3D LN T zone stromal network by culturing murine TRC clones within a macroporous polyurethane scaffold containing type I collagen and Matrigel and applying slow interstitial flow (1-23 microm/min). We show that the 3D environment and slow interstitial flow are important regulators of TRC morphology, organization, and CCL21 secretion. Without flow, CCL21 expression could not be detected. Furthermore, when flow through the LN was blocked in mice in vivo, CCL21 gene expression was down-regulated within 2 h. These results highlight the importance of lymph flow as a homeostatic regulator of constitutive TRC activity and introduce the concept that increased lymph flow may act as an early inflammatory cue to enhance CCL21 expression by TRCs, thereby ensuring efficient immune cell trafficking, lymph sampling, and immune response induction.

Elevated levels of MIC-1/GDF15 in the cerebrospinal fluid of patients are associated with glioblastoma and worse outcome.

For patients with brain tumors identification of diagnostic and prognostic markers in easy accessible biological material, such as plasma or cerebrospinal fluid (CSF), would greatly facilitate patient management. MIC-1/GDF15 (growth differentiation factor 15) is a secreted protein of the TGF-beta superfamily and emerged as a candidate marker exhibiting increasing mRNA expression during malignant progression of glioma. Determination of MIC-1/GDF15 protein levels by ELISA in the CSF of a cohort of 94 patients with intracranial tumors including gliomas, meningioma and metastasis revealed significantly increased concentrations in glioblastoma patients (median, 229 pg/ml) when compared with control cohort of patients treated for non-neoplastic diseases (median below limit of detection of 156 pg/ml, p < 0.0001, Mann-Whitney test). However, plasma MIC-1/GDF15 levels were not elevated in the matching plasma samples from these patients. Most interestingly, patients with glioblastoma and increased CSF MIC-1/GDF15 had a shorter survival (p = 0.007, log-rank test). In conclusion, MIC-1/GDF15 protein measured in the CSF may have diagnostic and prognostic value in patients with intracranial tumors.

Detection of hepatitis A, B, and C virus-specific antibodies using oral fluid for epidemiological studies

In this report, we examine the adaptability of commercially available serological kits to detect antibodies markers for viral hepatitis in oral fluid samples. We also assessed the prevalence of hepatitis A, B, and C virus-specific antibodies, and related risk factors for these infectious diseases through sensitivity of the tests in saliva samples to evaluate if oral fluid can be an alternative tool to substitute serum in diagnosis of acute viral hepatitis and in epidemiological studies. One hundred and ten paired serum and saliva specimens from suspect patients of having acute hepatitis were collected to detect antibodies to hepatitis A (total and IgM), hepatitis B (anti-HBs, total anti-HBc and IgM anti-HBc), and hepatitis C (anti-HCV) using commercially available enzyme-linked immunossorbent assay (EIA). In relation to serum samples, oral fluid assay sensitivity and specificity were as follows: 87 and 100% for total anti-HAV, 79 and 100% for anti-HAV IgM, 6 and 95% for anti-HBs, 13 and 100% for total anti-HBc, 100 and 100% for anti-HBc IgM, and 75 and 100% for anti-HCV. The consistency observed between antibodies tests in saliva and expected risk factors for hepatitis A and C suggests that the saliva method could replace serum in epidemiological studies for hepatitis A and C.

Taenia solium metacestode immunodominant peptides recognized by IgG antibodies in cerebrospinal fluid and serum paired samples from patients with active and inactive neurocysticercosis

The aim of this study was to test if serological distinction between patients with active and inactive neurocysticercosis (NCC), could be accomplished by the recognition of immunodominant peptides in total saline antigenic extract of Taenia solium metacestodes by IgG antibody in cerebrospinal fluid (CSF) and serum paired samples. CSF and serum samples of 10 each, active NCC patients, inactive NCC, and individuals with other neurological disorders, were used to recognize the antigenic peptides by western blot (WB). In the active NCC the 28-32 and 39-42 kDa peptides were more frequently detected in CSF than in sera (p < 0.05). The 47-52, 64-68, and 70 kDa antigens showed high frequencies in both samples from patients with active NCC. All the CSF samples of inactive NCC and other neurological disorder (control) patients tested negative, while serum samples from these last two groups recognized mainly the 80, 86, 95, and 98 kDa bands. This finding eliminates the use of the high molecular weigh bands (> 80 kDa) for diagnosis of NCC. The final conclusions were that the difference between active and inactive NCC may be done with the detection of peptides only in the CSF samples and that the 47-52, 64-68, and 70 kDa bands may be included as specific markers for active NCC when detected in CSF samples by WB using total saline extract of T. solium metacestode.

A fatal overdose of cocaine associated with coingestion of marijuana, buprenorphine, and fluoxetine. Body fluid and tissue distribution of cocaine and its metabolites determined by hydrophilic interaction chromatography-mass spectrometry(HILIC-MS).

Chromatographic separation of highly polar basic drugs with ideal ionspray mass spectrometry volatile mobile phases is a difficult challenge. A new quantification procedure was developed using hydrophilic interaction chromatography-mass spectrometry with turbo-ionspray ionization in the positive mode. After addition of deuterated internal standards and simple clean-up liquid extraction, the dried extracts were reconstituted in 500 microL pure acetonitrile and 5 microL was directly injected onto a Waters Atlantis HILIC 150- x 2.1-mm, 3-microm column. Chromatographic separations of cocaine, seven metabolites, and anhydroecgonine were obtained by linear gradient-elution with decreasing high concentrations of acetonitrile (80-56% in 18 min). This high proportion of organic solvent makes it easier to be coupled with MS. The eluent was buffered with 2 mM ammonium acetate at pH 4.5. Except for m-hydroxy-benzoylecgonine, the within-day and between-day precisions at 20, 100, and 500 ng/mL were below 7 and 19.1%, respectively. Accuracy was also below +/- 13.5% at all tested concentrations. The limit of quantification was 5 ng/mL (%Diff < 16.1, %RSD < 4.3) and the limit of detection below 0.5 ng/mL. This method was successfully applied to a fatal overdose. In Switzerland, cocaine abuse has dramatically increased in the last few years. A 45-year-old man, a known HIV-positive drug user, was found dead at home. According to relatives, cocaine was self-injected about 10 times during the evening before death. A low amount of cocaine (0.45 mg) was detected in the bloody fluid taken from a syringe discovered near the corpse. Besides injection marks, no significant lesions were detected during the forensic autopsy. Toxicological investigations showed high cocaine concentrations in all body fluids and tissues. The peripheral blood concentrations of cocaine, benzoylecgonine, and methylecgonine were 5.0, 10.4, and 4.1 mg/L, respectively. The brain concentrations of cocaine, benzoylecgonine, and methylecgonine were 21.2, 3.8, and 3.3 mg/kg, respectively. The highest concentrations of norcocaine (about 1 mg/L) were measured in bile and urine. Very high levels of cocaine were determined in hair (160 ng/mg), indicating chronic cocaine use. A low concentration of anhydroecgonine methylester was also found in urine (0.65 mg/L) suggesting recent cocaine inhalation. Therapeutic blood concentrations of fluoxetine (0.15 mg/L) and buprenorphine (0.1 microg/L) were also discovered. A relatively high concentration of Delta(9)-THC was measured both in peripheral blood (8.2 microg/L) and brain cortex (13.5 microg/kg), suggesting that the victim was under the influence of cannabis at the time of death. In addition, fluoxetine might have enhanced the toxic effects of cocaine because of its weak pro-arrhythmogenic properties. Likewise, combination of cannabinoids and cocaine might have increase detrimental cardiovascular effects. Altogether, these results indicate a lethal cocaine overdose with a minor contribution of fluoxetine and cannabinoids.

Alveolar fluid clearance in healthy pigs and influence of positive end-expiratory pressure

INTRODUCTION The objectives were to characterize alveolar fluid clearance (AFC) in pigs with normal lungs and to analyze the effect of immediate application of positive end-expiratory pressure (PEEP). METHODS Animals (n = 25) were mechanically ventilated and divided into four groups: small edema (SE) group, producing pulmonary edema (PE) by intratracheal instillation of 4 ml/kg of saline solution; small edema with PEEP (SE + PEEP) group, same as previous but applying PEEP of 10 cmH2O; large edema (LE) group, producing PE by instillation of 10 ml/kg of saline solution; and large edema with PEEP (LE + PEEP) group, same as LE group but applying PEEP of 10 cmH2O. AFC was estimated from differences in extravascular lung water values obtained by transpulmonary thermodilution method. RESULTS At one hour, AFC was 19.4% in SE group and 18.0% in LE group. In the SE + PEEP group, the AFC rate was higher at one hour than at subsequent time points and higher than in the SE group (45.4% vs. 19.4% at one hour, P < 0.05). The AFC rate was also significantly higher in the LE + PEEP than in the LE group at three hours and four hours. CONCLUSIONS In this pig model, the AFC rate is around 20% at one hour and around 50% at four hours, regardless of the amount of edema, and is increased by the application of PEEP.

A universal fluid cell for the imaging of biological specimens in the atomic force microscope.

Recently, atomic force microscope (AFM) manufacturers have begun producing instruments specifically designed to image biological specimens. In most instances, they are integrated with an inverted optical microscope, which permits concurrent optical and AFM imaging. An important component of the set-up is the imaging chamber, whose design determines the nature of the experiments that can be conducted. Many different imaging chamber designs are available, usually designed to optimize a single parameter, such as the dimensions of the substrate or the volume of fluid that can be used throughout the experiment. In this report, we present a universal fluid cell, which simultaneously optimizes all of the parameters that are important for the imaging of biological specimens in the AFM. This novel imaging chamber has been successfully tested using mammalian, plant, and microbial cells.

Meaning of the λ parameter of skew–normal and log–skew normal distributions in fluid geochemistry

The literature related to skew–normal distributions has grown rapidly in recent yearsbut at the moment few applications concern the description of natural phenomena withthis type of probability models, as well as the interpretation of their parameters. Theskew–normal distributions family represents an extension of the normal family to whicha parameter (λ) has been added to regulate the skewness. The development of this theoreticalfield has followed the general tendency in Statistics towards more flexible methodsto represent features of the data, as adequately as possible, and to reduce unrealisticassumptions as the normality that underlies most methods of univariate and multivariateanalysis. In this paper an investigation on the shape of the frequency distribution of thelogratio ln(Cl−/Na+) whose components are related to waters composition for 26 wells,has been performed. Samples have been collected around the active center of Vulcanoisland (Aeolian archipelago, southern Italy) from 1977 up to now at time intervals ofabout six months. Data of the logratio have been tentatively modeled by evaluating theperformance of the skew–normal model for each well. Values of the λ parameter havebeen compared by considering temperature and spatial position of the sampling points.Preliminary results indicate that changes in λ values can be related to the nature ofenvironmental processes affecting the data

Thermodynamics and log–contrast analysis in fluid geochemistry

There are two principal chemical concepts that are important for studying the naturalenvironment. The first one is thermodynamics, which describes whether a system is atequilibrium or can spontaneously change by chemical reactions. The second main conceptis how fast chemical reactions (kinetics or rate of chemical change) take place wheneverthey start. In this work we examine a natural system in which both thermodynamics andkinetic factors are important in determining the abundance of NH+4 , NO−2 and NO−3 insuperficial waters. Samples were collected in the Arno Basin (Tuscany, Italy), a system inwhich natural and antrophic effects both contribute to highly modify the chemical compositionof water. Thermodynamical modelling based on the reduction-oxidation reactionsinvolving the passage NH+4 -& NO−2 -& NO−3 in equilibrium conditions has allowed todetermine the Eh redox potential values able to characterise the state of each sample and,consequently, of the fluid environment from which it was drawn. Just as pH expressesthe concentration of H+ in solution, redox potential is used to express the tendency of anenvironment to receive or supply electrons. In this context, oxic environments, as thoseof river systems, are said to have a high redox potential because O2 is available as anelectron acceptor.Principles of thermodynamics and chemical kinetics allow to obtain a model that oftendoes not completely describe the reality of natural systems. Chemical reactions may indeedfail to achieve equilibrium because the products escape from the site of the rectionor because reactions involving the trasformation are very slow, so that non-equilibriumconditions exist for long periods. Moreover, reaction rates can be sensitive to poorly understoodcatalytic effects or to surface effects, while variables as concentration (a largenumber of chemical species can coexist and interact concurrently), temperature and pressurecan have large gradients in natural systems. By taking into account this, data of 91water samples have been modelled by using statistical methodologies for compositionaldata. The application of log–contrast analysis has allowed to obtain statistical parametersto be correlated with the calculated Eh values. In this way, natural conditions in whichchemical equilibrium is hypothesised, as well as underlying fast reactions, are comparedwith those described by a stochastic approach