Determination of emission factors from a landfill through an inverse methodology: Experimental determination of ambient air concentrations and use of numerical modelling

The application of numeric modelling for determining the impact of landfills needs for reliable emission source data. In this study, a methodology for the characterization of the emission profiles of the different sources present in landfills for emission factors determination, applying an indirect methodology, is presented. Ambient air concentrations of volatile organic compounds (VOCs), hydrogen sulphide (H2S) and ammonia (NH3) were determined in three potentially emission sources in Can Mata landfill (Hostalets de Pierola, Catalonia, Spain): dumping areas, pre-closed zone and leachate reservoir as well as in biogas, for the determination of emission factors. Multi-sorbent bed and Tenax TA tubes were used for a wide range of VOCs sampling, and analysis was conducted through TD-GC/MS. H2S and NH3 were sampled and analysed using Radiello passive samplers. The highest total VOC (TVOC) concentrations were found in dumping areas (0.7-3.5 mg m-3), followed by leachate reservoir (0.3-0.6 mg m-3) and pre-closed area (77-165 μg m-3). On the other hand, the highest H2S and NH3 concentrations were found in leachate reservoir, presenting values of 0.8-1.1 mg m-3 and 1.7-1.8 mg m-3, respectively. With the application of odour thresholds to the concentrations obtained, the most critical compounds regarding odour annoyances were determined. The highest odour units (O.U.) were found in leachate reservoir due to H2S concentrations, whereas VOCs contributed mainly to O.U. in the dumping areas. The obtained ambient air concentrations were used for the indirect determination of the emission factors through numerical modelling using a Eulerian dispersion model. The emission factors obtained for the landfill for TVOC, H2S and NH3 were in the range of 0.44-10.9 g s-1, 0.16-1.02 g s-1 and 0.23-1.82 g s-1, respectively, depending on the emission source. Reliable emission factors are crucial to obtain landfill impact maps, which are essential for the correct management of these facilities.

Comparison of neutron and secondary gamma dose assessment using polygon mesh and voxel computational phantoms

The newly developed mesh-type reference computational phantoms (MRCPs) represent the evolution of the previous reference phantoms and a more detailed description of the human body, addressing the voxel reference phantom limitations. These allow for a more accurate dose calculation in the human body, which in some cases results in a significant difference of the calculated quantities. In this work, the absorbed dose calculation due to neutrons and gammas was calculated using a voxel and a mesh-type computational phantom. The goal was to understand how a more accurate description of the human body affects the estimated neutron dose. The phantoms were tested in a real-case scenario: they were placed in front of a neutron Howitzer container model using PHITS. This model corresponds to the neutron Howitzer container at the Neutron Measurements Laboratory of the Energy Engineering Department of the Polytechnic University of Madrid (UPM), and at the time of measurement it was equipped with a ²⁴¹Am-Be neutron source of 74 GBq in its center. The container allows the source to be in either the irradiation or the storage position. Results show that when dealing with neutrons, the dose deviation when using GOLEM or the MRCP leads to a general 20%-30% deviation that goes up to above 400% in small thin structures such as the eye.

The work programme of NERIS in post-accident recovery

NERIS is the European platform on preparedness for nuclear and radiological emergency response and recovery. Created in 2010 with 57 organisations from 28 different countries, the objectives of the platform are to: improve the effectiveness and coherency of current approaches to preparedness; identify further development needs; improve 'know how' and technical expertise; and establish a forum for dialogue and methodological development. The NERIS Strategic Research Agenda is now structured with three main challenges: (i) radiological impact assessments during all phases of nuclear and radiological events; (ii) countermeasures and countermeasure strategies in emergency and recovery, decision support, and disaster informatics; and (iii) setting up a multi-faceted framework for preparedness for emergency response and recovery. The Fukushima accident has highlighted some key issues for further consideration in NERIS research activities, including: the importance of transparency of decision-making processes at local, regional, and national levels; the key role of access to environmental monitoring; the importance of dealing with uncertainties in assessment and management of the different phases of the accident; the use of modern social media in the exchange of information; the role of stakeholder involvement processes in both emergency and recovery situations; considerations of societal, ethical, and economic aspects; and the reinforcement of education and training for various actors. This paper emphasises the main issues at stake for NERIS for post-accident management.

Units related to radiation exposure and radioactivity in mass media: the Fukushima case study in Europe and Russia

Using an analysis of the way European newspapers covered the Fukushima nuclear accident, this article explores how the mass media transmit information about radiation risks from experts to the general public. The study applied a media content analysis method on a total of 1340 articles from 12 leading newspapers in 6 countries: Belgium (N = 260), Italy (N = 270), Norway (N = 133), Russia (N = 172), Slovenia (N = 190) and Spain (N = 315). All articles analysed were selected as being directly or indirectly related to the Fukushima accident by containing the word 'nuclear' and/or 'Fukushima' and were published between the 11th March and the 11th May 2011. The data presented here focus specifically on a cross-cultural comparison of the way the media use quantitative units. Results suggest that although experts are accustomed to communicating about radiological risks in technical language, often using quantitative units to describe the risks, mass media do not tend to use these units in their reporting. Although the study found a large variation in the measurement units used in different countries, it appeared that journalists in all the analysed countries preferred to describe radioactivity by comparing different radiation exposures, rather than reporting the actual measured units. The paper concludes with some practical guidelines for sound public communication about radiation risks.

First Report of Fusarium equiseti Causing Damping-Off Disease on Aleppo Pine in Algeria

The Aleppo pine (Pinus halepensis Mill.) is a conifer native to the Mediterranean region. In 2008 and 2009, a survey of Aleppo pine seedling diseases was performed in three forest nurseries from Relizane, Sidi Bel Abbes, and Tlemcen provinces in northwestern Algeria. Aleppo pine seedlings showed symptoms of pre- and post-emergence damping-off disease, with an incidence of 64 to 77%. Four composite samples were taken from each location. Disinfested root and root collar segments, approximately 5 mm in length, were cultured on potato dextrose agar (PDA) and incubated at 25°C, and hyphal tips were transferred to PDA. Fusarium equiseti (Corda) Sacc. (teleomorph: Gibberella intricans Wollenw.) was identified from roots of two seedlings from the Sidi Bel Abbes nursery. Morphological identification was done according to Fusarium keys (2). PDA colonies with abundant, loosely floccose, whitish aerial mycelium and beige pigmentation were observed. Macroconidia with usually 5 to 6 septa, 31 to 45 μm long. A pronounced dorsiventral curvature, tapered and elongated apical cell, and prominent foot shape were observed. Microconidia were absent. Chlamydospores were produced in hyphae, most often intercalary, solitary, in pairs, frequently forming chains or clusters, globose (7 to 13 μm). To confirm the identity of this fungus, the internal transcribed spacer of F3RS1 and F19RS1 isolates of F. equiseti were amplified and sequenced using ITS1 and ITS4 primers (4), GenBank accession nos. JX114784 and JX114791, respectively. Those sequences bore 100% (HQ671182) similarity with sequences of F. equiseti in GenBank. Pathogenicity tests were performed to fulfill Koch's postulates. Inoculum was produced by adding a 5-mm-diameter plug from a 7-day-old CMA petri dish culture to a previously sterilized 500 ml flask (237.5 g sand, 12.5 g cornmeal, 80 ml sterile distilled water), shaken over 9 days at 25°C, and mixed with sterile sandy clay soil at 1:3 (v:v). Infested soil was then transferred to 500 ml pots, and 10 Aleppo pine seeds were planted per pot. A completely randomized design was used with three replicates per isolate and three control pots with a similar non-infested soil. After 1 month at 25°C the two tested isolates caused typical damping-off symptoms (collar rot) on seedlings and were re-isolated from recently infected tissues. The percentages of the inoculated plants that became infected were 59 to 65% among isolates (0% in control pots). To our knowledge, infection by F. equiseti is a first report on Aleppo pine in northwestern Algeria, Northern Africa, and globally, and on conifers in the Mediterranean region (1,3). In Algeria, F. equiseti is associated with black pepper (Piper nigrum L.) (3). These findings highlight the moderate impact of F. equiseti on the production of Aleppo seedling stock for reforestation activities in northwestern Algeria. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory. ARS, USDA, Beltsville, MD. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , February 20, 2013. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006. (3) D. W. Minter. Cybertruffle's Robigalia, Observations of Fungi and their Associated Organisms. Retrieved from http://www.cybertruffle.org.uk/robigalia/eng/ , February 20, 2013. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

Surface emission determination of volatile organic compounds (VOC) from a closed industrial waste landfill using a self-designed static flux chamber

Closed landfills can be a source of VOC and odorous nuisances to their atmospheric surroundings. A self-designed cylindrical air flux chamber was used to measure VOC surface emissions in a closed industrial landfill located in Cerdanyola del Vallès, Catalonia, Spain. The two main objectives of the study were the evaluation of the performance of the chamber setup in typical measurement conditions and the determination of the emission rates of 60 different VOC from that industrial landfill, generating a valuable database that can be useful in future studies related to industrial landfill management. Triplicate samples were taken in five selected sampling points. VOC were sampled dynamically using multi-sorbent bed tubes (Carbotrap, Carbopack X, Carboxen 569) connected to SKC AirCheck 2000 pumps. The analysis was performed by automatic thermal desorption coupled with a capillary gas chromatograph/mass spectrometry detector. The emission rates of sixty VOC were calculated for each sampling point in an effort to characterize surface emissions. To calculate average, minimum and maximum emission values for each VOC, the results were analyzed by three different methods: Global, Kriging and Tributary area. Global and Tributary area methodologies presented similar values, with total VOC emissions of 237 ± 48 and 222 ± 46 g day(-1), respectively; however, Kriging values were lower, 77 ± 17 gd ay(-1). The main contributors to the total emission rate were aldehydes (nonanal and decanal), acetic acid, ketones (acetone), aromatic hydrocarbons and alcohols. Most aromatic hydrocarbon (except benzene, naphthalene and methylnaphthalenes) and aldehyde emission rates exhibited strong correlations with the rest of VOC of their family, indicating a possible common source of these compounds. B:T ratio obtained from the emission rates of the studied landfill suggested that the factors that regulate aromatic hydrocarbon distributions in the landfill emissions are different from the ones from urban areas. Environmental conditions (atmospheric pressure, temperature and relative humidity) did not alter the pollutant emission fluxes.

First Report of Fusarium chlamydosporum Causing Damping-Off Disease on Aleppo Pine in Algeria

The Aleppo pine (Pinus halepensis Mill.) is a conifer native to the Mediterranean region. In 2008 and 2009, a survey of Aleppo pine seedling diseases was performed in three forest nurseries from the Relizane, Sidi Bel Abbes, and Tlemcen departments in northwestern Algeria. One- to two-month-old Aleppo pine seedlings showed symptoms of damping-off in pre- and post-emergence (typical seedling collar rot). The problem was widespread with a disease incidence of 64 to 77% and an annual impact of US$50,000. Disinfested root and root collar segments (from four composite samples per location), approximately 5 mm in length, were cultured on PDA and incubated at 25°C and day/night light. Two (from 21) isolates were identified morphologically (2) as the anamorph Fusarium chlamydosporum Wollenw. & Reinking and isolated from collar rots of Relizane forest nursery seedlings. Colony development on PDA media was fast; 32 mm diameter colonies developed after 3 days. Colonies were white. Mycelia were floccose, fairly dense, off-white, and turned a lilac color in older portions of the colony. Macroconidia were thick-walled and moderately curved with unequal dorsiventral curvature (the lower wall is almost straight), short, curved and pointed apical cell, usually notched, but occasionally foot shaped basal cell, 3- to 5-septate, and 2 × 8 to 21 μm. Microconidia were abundant, 0-septate, and 2 × 6 to 9 μm. Chlamydospores were abundant, formed rapidly in single chains or clusters, and 8 to 15 μm diameter. To confirm the identity of this fungus, the internal transcribed spacer of F12RR and F4SR isolates of F. chlamydosporum were amplified and sequenced using ITS1 and ITS4 primers (4). Sequences were deposited in GenBank under accessions JX114795 and JX114789, respectively. Those sequences bore 99% similarity with reference sequence AY213655 (2) and 100% with HQ671187, also found 99 to 100% similarity with F. equiseti (Corda) Sacc. but with different conidia. Pathogenicity tests were performed to fulfill Koch's postulates. Inoculum was produced by adding a 5 mm diam. plug from a 7-day-old CMA petri dish culture to a previously sterilized 500 ml flask (237.5 g sand, 12.5 g cornmeal, 80 ml SDW), shaken over 9 days, and mixed with sterile soil at 1:3 (v:v). Infested soil was then transferred to 500 ml pots, and 10 seeds were planted. A completely randomized design was used with three replicates per isolate and three control pots. After 1 month, two tested isolates caused typical damping-off symptoms on seedlings. The percentage of the plants that became infected was 65 to 77%. To our knowledge (1,3), this is the first report of F. chlamydosporum on Aleppo pine in northwestern Algeria. It is also the first report of this fungal species affecting the Aleppo pine throughout the world, and on conifers in Africa and the Mediterranean region (1,3). References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Syst. Mycol. Microbiol. Lab. ARS, USDA, Beltsville, MD. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , February 20, 2013. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006. (3) D. W. Minter. Cybertruffle's Robigalia, Observations of Fungi and their Associated Organisms. Retrieved from http://www.cybertruffle.org.uk/robigalia/eng/ , February 20, 2013. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

First Report of Globisporangium ultimum Causing Pythium Damping-Off on Aleppo Pine in Algeria, Africa, and the Mediterranean Region

Globisporangium ultimum (Trow) Uzuhashi, Tojo & Kakish. (syn. Pythium ultimum Trow, syn. P. ultimum Trow var. ultimum) is a known oomycetal species from Pythium s.l. causing damping-off and/or root rot on a great variety of plants throughout the world, including some pine species (Pinus L.) and conifers (2,3). Aleppo pine (Pinus halepensis Mill.) is a common native forest tree in the Mediterranean region. Pre- and post-emergence damping-off disease symptoms were observed during 2008 and 2009 in four forest nurseries from northwestern Algeria (Relizane, Sidi Belabes, and Tlemcen departments). This disease occurred under cool conditions, and Aleppo pines were significantly affected, reducing seedling emergence. Disinfected segments, about 5 mm in length, from decayed root and collar, were cultured on CMA at 25°C. This oomycetal species was identified based on the species description in Pythium keys (3,4). For the molecular identification, PCR was used to amplify the ITS region of Pythium isolates. It was amplified with the flanking primers ITS1 and ITS4, and these products were directly sequenced. Sequence data were compared to known sequences deposited in the NCBI non redundant database to confirm morphological identification. A BLAST search identified U3CR, U7CR, U1RT, U2CR, U4CR, U14CR, U7RT, and U17RT isolates (GenBank Accession Nos. JX191921, 22, 27, 29, 31, and 33 to 35, respectively) as G. ultimum based on 100% similarity with corresponding sequence of the reference isolate no. UZ056 MAFF240024 (AB468781) (3). Phytopathogenicity testing was conducted in a petri dish and pot experiment. In the petri dish experiment, a 3 mm diameter plug was transferred from a 7-day-old CMA colony to the center of a CMA petri dish, with three replicates per isolate, and three control plates were inoculated with sterile agar plugs. After 72 h, 10 Aleppo pine seeds were placed equally spaced to 1 cm from the edge of each plug. After 7 days at 22°C in the dark, germination inhibition (46.1 to 87.6%) and root growth inhibition (62.3 to 92.2%) were calculated. In the control plates, germination failure (13.4%) and root length (27.7 cm) were observed. For the pot experiment, inocula were produced by adding a 5 mm diameter plug from a 7-day-old CMA culture to a previously sterilized 500 ml flask containing 237.5 g sand, 12.5 g cornmeal, and 80 ml SDW. Nine-day-old inoculum was mixed with sterile soil at a rate of 1:3 (v:v). Inoculum was transferred to 500 ml pot, and 10 Aleppo pine seeds were planted, with three replicates per isolate, and three control pots were used. After 2 weeks, all of the isolates tested caused typical symptoms of Aleppo pine Pythium damping-off, the percentage of inoculated plants that became infected was 36.6 to 83.3%. In the control pots, no infected plants were observed. To our knowledge, this is the first report of G. ultimum causing damping-off on Aleppo pine in Algeria, Africa, and the Mediterranean Region. Before, Aleppo pine damping-off caused by G. ultimum was reported in Australia (1). References: (1) R. P. Cook and A. J. Dubé. Host-pathogen index of plant diseases in South Australia. SADA, Melbourne, Australia, 1989. (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory. ARS, USDA, Bestville, MD. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , June 24, 2012. (3) S. Uzuhashi et al. Mycoscience 51:337, 2010. (4) A. J. van der Plaats-Niterink. Stud. Mycol. 21:1, 1981.

First Report of Fusarium redolens as a Causal Agent of Aleppo Pine Damping-Off in Algeria

Aleppo pine (Pinus halepensis Mill.) is a common native coniferous tree in the natural forests of the Mediterranean region. In 2008 and 2009, a survey of Aleppo pine seedling diseases was performed in three forest nurseries from Relizane, Sidi Bel Abbes, and Tlemcen departments in northwestern Algeria. Aleppo pine seedlings showed symptoms of pre- and post-emergence damping-off, resulting in severe crop losses. The problem was widespread with a disease incidence of 64 to 77%. Fusarium redolens Wollenw. was isolated from Relizane and Sidi Bel Abbes forest nurseries. Disinfested root and root collar segments, approximately 5 mm in length, were cultured on potato dextrose agar (PDA) and incubated at 25°C. Morphological identification was done according to Fusarium keys (2). PDA colonies consisted of flat mycelium with sparse white aerial hyphae. Macroconidia with three to five septa, 24 to 43.8 μm long, widest upper third, hooked apical cell, and foot shaped basal cell were observed. Microconidia with zero to one septa, 6.8 to 10.4 μm long, oval to cylindrical, and produced on monophialides were also observed. Chlamydospores were produced abundantly in terminal and intercalary chains, in 3- to 4-week-old cultures. To confirm the identity of the fungus, the internal transcribed spacer (ITS) of F5RS3, F91SR, F55RS1, F8RS3, and F09SS1 isolates of F. redolens were amplified and sequenced using ITS 1 and ITS 4 primers (3). GenBank Accession Nos. are JX051323 to 26, and JX114783, respectively. Those sequences bore 99% (JF311916) and 100% (U34565) similarity with sequences of F. redolens in GenBank. A Fusarium pathogenicity assay was used to complete Koch's postulates. Inoculum was produced by adding a 5 mm diam. agar disc from a 7-day-old CMA petri dish culture to a previously sterilized 500 ml flask (237.5 g of sand, 12.5 g of cornmeal, and 80 ml of deionized H₂O). Isolates were allowed to colonize the medium for 9 days, and flasks were shaken every day. The inoculum was mixed with sterile soil at a rate of 3:1 (v:v). Infested soil was then transferred to 500 ml pots, and 10 Aleppo pine seeds were planted. A completely randomized design was used with three replicates. After 1 month, all tested isolates caused typical damping-off symptoms on seedlings. The percentage of the inoculated plants that became infected was 53 to 91%. To our knowledge, this is the first report of F. redolens being pathogenic on Aleppo pine in northwestern Algeria and throughout the world. In Algeria, F. redolens has been reported on tomato (Solanum lycopersicum L.) (1), suggesting that it is adapted to the conditions of this area and could become a major threat to regional plant production. The annual economic impact of this disease was estimated at approximately US$50,000 per forest nursery. References: (1) N. Hamini-Kadar et al. New Dis. Rep. 22:3, 2010. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, Iowa, 2006. (3) T. J. White et al. Pages 315-322 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

First Report of Fusarium acuminatum Causing Damping-Off Disease on Aleppo Pine in Algeria

The Aleppo pine (Pinus halepensis Mill.) is a conifer native to the Mediterranean region. In autumn and spring of 2008 to 2009, a survey of Aleppo pine seedling diseases was carried out in three forest nurseries from the Relizane, Sidi Bel Abbes, and Tlemcen departments in northwestern Algeria. Aleppo pine seedlings were potted from the soil. In all three nurseries, 1- to 2-month old seedlings showed symptoms of damping-off disease in pre- and post-emergence (collar rot) with a disease incidence of 64, 77, and 72%, respectively. Disinfected collar segments, about 5 mm in length, were plated on PDA and petri dishes incubated at 25°C. A Fusarium sp. was consistently isolated from tissues and all isolates were morphologically identified as Fusarium acuminatum Ellis & Everh. (teleomorph: Gibberella acuminata Wollenw.) according to Fusarium keys (2). Colony growth was 43 mm after 3 days on PDA; the aerial mycelium was white, developing a brownish tinge in the center on PDA; macroconidia were formed in orange sporodochia, broadly falcate, strongly septate, 3 to 5 septa, the apical cell with an incurved elongation, distinct foot shape, 3 to 4 × 20 to 50 μm; microconidia were usually absent for isolates other than F12SS1, reniform, septate, 5 to 6 × 6 to 10 μm, in monophialides; chlamydospores were formed in chains, 6 to 13 μm. For the molecular identification, ITS regions of Fusarium isolates were amplified with the primers ITS1 and ITS4, and products were directly sequenced in both strands using the same primers ITS 1 and ITS4. Sequences were compared to known sequences deposited in the NCBI non redundant database to confirm morphological identification. An NCBI BLAST search identified isolates F12SS1, F14SS3, F30SS3, and F25SR as F. acuminatum based on 100% similarity with corresponding sequences. GenBank Accession Nos. were JX114788, JX114785, JX114782, and JX114790, respectively. Pathogenicity tests were performed to fulfill Koch's postulates. Inocula were produced by adding a 5-mm diameter plug from a 7-day-old CMA petri dish culture to a previously sterilized 500-ml flask (237.5 g sand, 12.5 g cornmeal, 80 ml SDW), shaken over 9 days, and mixed with sterile soil at 1:3 (v:v). The inocula were transferred to a 500-ml pot, and 10 Aleppo pine seeds were planted with three replicates. After 1 month, all tested isolates caused typical symptoms on seedlings and the proportion of infected seedlings per each isolate was 50, 53.33, 56.66, 60, and 63.33%, respectively. There are many reports of F. acuminatum associated to conifer seedlings in nurseries (1,3) and most of them are conflicting because in some reports this species is considered non-pathogenic or only a seed contaminant and others consider it as a pathogen. To our knowledge, F. acuminatum is a first report on the Aleppo pine in northwestern Algeria, northern Africa. It is also the first report of this fungal species affecting the Aleppo pine throughout the world, and on conifers in Africa and the Mediterranean region. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory. ARS, USDA., Bestville, Maryland, USA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , June 18, 2012. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, Iowa, USA, 2006. (3) D. W. Minter. Cybertruffle's Robigalia, Observations of Fungi and their Associated Organisms. Retrieved from http://www.cybertruffle.org.uk/robigalia/eng/ , June 18, 2012.

Characterization and determination of the odorous charge in the indoor air of a waste treatment facility through the evaluation of volatile organic compounds (VOCs) using TD-GC/MS

Municipal solid waste treatment facilities are generally faced with odorous nuisance problems. Characterizing and determining the odorous charge of indoor air through odour units (OU) is an advantageous approach to evaluate indoor air quality and discomfort. The assessment of the OU can be done through the determination of volatile organic compounds (VOCs) concentrations and the knowledge of their odour thresholds. The evaluation of the presented methodology was done in a mechanical-biological waste treatment plant with a processing capacity of 245.000 tons year(-1) of municipal residues. The sampling was carried out in five indoor selected locations of the plant (Platform of Rotating Biostabilizers, Shipping warehouse, Composting tunnels, Digest centrifugals, and Humid pre-treatment) during the month of July 2011. VOC and volatile sulphur compounds (VSCs) were sampled using multi-sorbent bed (Carbotrap, Carbopack X, Carboxen 569) and Tenax TA tubes, respectively, with SKC AirCheck 2000 pumps. The analysis was performed by automatic thermal desorption (ATD) coupled with a capillary gas chromatography (GC)/mass spectrometry detector (MSD). One hundred and thirty chemical compounds were determined qualitatively in all the studied points (mainly alkanes, aromatic hydrocarbons, alcohols, aldehydes, esters, and terpenes), from which 86 were quantified due to their odorous characteristics as well as their potentiality of having negative health effects. The application of the present methodology in a municipal solid waste treatment facility has proven to be useful in order to determine which type of VOC contribute substantially to the indoor air odorous charge, and thus it can be a helpful method to prevent the generation of these compounds during the treatment process, as well as to find a solution in order to suppress them.

[Anxiety and depression in carers of dependent patients]

OBJECTIVE

To determine the prevalence of depression and anxiety in main carers of dependent patients as defined by the Dependent Care Law 39/2006.

MATERIAL AND METHODS

We selected 294 main carers of dependent patients as defined by Law 39/2006, and performed a descriptive, cross-sectional and multi-centre study. They were recruited during the first semester of 2009 in 8 urban centres and 2 rural ones in the Communities of Andalusia and Murcia. We measured levels of anxiety and depression using the Hamilton scale, the social support by means of the Duke-UNK scale, sociodemographic, medical variables and associated with the support to the dependent person. The Chi-squared (chi), WiLcoxon and Student t tests were used to describe the data. Multivariate analysis was performed on the most significant data.

RESULTS

A total of 254 carers showed anxiety (86%) (95% CI: 82.47-90.31%) and depression 191 (65%) (95% CI: 59.51-70.41%). The presence of anxiety was statistically significant (P = .043) when associated to: being an unpaid carer, low social support, previous diagnosis of anxiety and depression, taking of psychiatric drugs, and diagnosis of depression using the Hamilton depression scale. The depression presence of depression is associated with: being an unpaid carer, family relationship, previous diagnosis of anxiety and depression, taking of psychiatric drugs, and with an anxiety diagnosis according to the Hamilton scale. No statistically significant differences were detected in the association between Levels of dependency and the appearance of depression and/or anxiety.

CONCLUSIONS

The prevalence of depression and anxiety in the carers of dependent patients is significantly greater than in the general population. The greater the social support the lower the prevalence of these disorders.

P3-05-04: Changes in Recurrence Risk of Breast Cancer Intrisic Subtypes over Time

Background: Gene expression profiling and their immunohistochemistry-based surrogates have consistently revealed prognostically significant breast cancer (BC) subtypes: Luminal A (Lum A), Luminal B (Lum B), HER2, Basal-like (BL) and Triple negative phenotype-nonbasal (TNP-nb). In addition, there are clinical evidence that hazard of BC recurrence varies over time with two peaks of high risk at 18–24 and 60 months. This study compares the time-related patterns of recurrence within BC subtypes. Methods: Tissue microarrays were constructed from 937 early BC patients diagnosed and treated at our Hospital from 1982 to 2005 with available archival paraffin tissue blocks. BC subtypes were defined using an immunopanel of estrogen receptor, progesterone receptor, HER2, epidermal growth factor receptor, cytokeratin 5/6 and Ki67 by prespecified published methods. Univariate and multivariate analysis (Cox regression) were performed on progression-free survival. Smoothed curves for hazard rates (HR) were estimated by a Kernel-like smoothing procedure. The statistical analysis was done by using the R software environment.

Results: Cases were classified as follows: Lum A 46.8%, Lum B 25.2%, HER2 11.3%, BL 11.3%, TNP-nb 5.4%. None of the patients were treated with adjuvant trastuzumab. With a median follow up of 80 months age, tumor size, nodal status and intrinsic subtypes were independent prognostic factors. HER2 and BL show high and early peak in HR curves and decreasing sharply to 36 and 48 months respectively. HR in Lum A, Lum B and TNP-nb exhibit a smoother and nearly steady curve.

Evaluation of the effect of different sampling time periods and ambient air pollutant concentrations on the performance of the Radiello diffusive sampler for the analysis of VOCs by TD-GC/MS

The effect of different sampling exposure times and ambient air pollutant concentrations on the performance of Radiello® samplers for analysis of volatile organic compounds (VOCs) is evaluated. Quadruplicate samples of Radiello® passive tubes were taken for 3, 4, 7 and 14 days. Samples were taken indoors during February and March 2010 and outdoors during July 2010 in La Canonja (Tarragona, Spain). The analysis was performed by automatic thermal desorption (ATD) coupled with capillary gas chromatography (GC)/mass spectrometry detection (MS). The results show significant differences (t-test, p < 0.05) between the amounts of VOCs obtained from the sum of two short sampling periods and a single equivalent longer sampling period for 65% of all the data. 17% of the results show significantly larger amounts of pollutant in the sum of two short sampling periods. Back diffusion due to changes in concentrations together with saturation and competitive effects between the compounds during longer sampling periods could be responsible for these differences. The other 48% of the results that are different show significantly larger amounts in the single equivalent longer sampling period. The remaining 35% of the results do not show significant differences. Although significant differences are observed in the amount of several VOCs collected over two shorter sampling intervals compared to the amount collected during a single equivalent longer sampling period, the ratios obtained are very close to unity (between 0.7 and 1.2 in 75% of cases). We conclude that Radiello® passive samplers are useful tools if their limitations are taken into account and the manufacturer's recommendations are followed.

Comparative study of the adsorption performance of an active multi-sorbent bed tube (Carbotrap, Carbopack X, Carboxen 569) and a Radiello(®) diffusive sampler for the analysis of VOCs

A simple comparison is made to evaluate the relative performance of active and passive sampling methods for the analysis of volatile organic compounds (VOCs) in ambient air. The active sampling is done through a multi-sorbent bed tube (Carbotrap, Carbopack X, Carboxen 569) created in our laboratory and the passive sampling through the Radiello(®) diffusive sampler specified for thermal desorption (filled with Carbograph 4). Daily duplicate samples of multi-sorbent bed tubes were taken during a period of 14 days. During the same period of time, quadruplicate samples of Radiello(®) tubes were taken during 3 days, 4 days, 7 days and 14 days. The sampling was carried out indoors during the months of February and March 2010 and outdoors during the month of July 2010 in La Canonja (Tarragona, Spain). The analysis was performed by automatic thermal desorption (ATD) coupled with capillary gas chromatography (GC)/mass spectrometry detector (MSD). The analytical performance of the two sampling approaches was evaluated by describing several quality assurance parameters. The results show that the analytical performances of the methodologies studied are quite similar. They display low limits of detection, good precision, accuracy and desorption efficiency, and low levels of breakthrough for multi-sorbent bed tubes. However, the two monitoring methods produced varying air-borne concentration data for most of the studied compounds, and the Radiello(®) samplers generally gave higher results. Sampling rates (Q(k)) were determined experimentally, and their values were higher than those supplied by the producer. As the experimental calculation of Q(k) values is generally carried out by the suppliers in exposure chambers with only the target compounds present in the air samples, as well as in concentrations dissimilar to those found in ambient air, the use of constant settled Q(k) can lead to inaccurate results in complex samples.

Computerised Decision Support Systems for the management of freshwater radioecological emergencies: assessment of the state-of-the-art with respect to the experiences and needs of end-users

Assessment of the environmental and radiological consequences of a nuclear accident requires the management of a great deal of data and information as well as the use of predictive models. Computerised Decision Support Systems (CDSS) are essential tools for this kind of complex assessment and for assisting experts with a rational decision process. The present work focuses on the assessment of the main features of selected state-of-the-art CDSS for off-site management of freshwater ecosystems contaminated by radionuclides. This study involved both developers and end-users of the assessed CDSS and was based on practical customisation exercises, installation and application of the decision systems. Potential end-users can benefit from the availability of several ready-to-use CDSS that allow one to run different kinds of models aimed at predicting the behaviour of radionuclides in aquatic ecosystems, evaluating doses to humans, assessing the effectiveness of different kinds of environmental management interventions and ranking these interventions, accounting for their social, economic and environmental impacts. As a result of the present assessment, the importance of CDSS "integration" became apparent: in many circumstances, different CDSS can be used as complementary tools for the decision-making process. The results of this assessment can also be useful for the future development and improvement of the CDSS.

ICRP Publication 111 - Application of the Commission's recommendations to the protection of people living in long-term contaminated areas after a nuclear accident or a radiation emergency

In this report, the Commission provides guidance for the protection of people living in long-term contaminated areas resulting from either a nuclear accident or a radiation emergency. The report considers the effects of such events on the affected population. This includes the pathways of human exposure, the types of exposed populations, and the characteristics of exposures. Although the focus is on radiation protection considerations, the report also recognises the complexity of post-accident situations, which cannot be managed without addressing all the affected domains of daily life, i.e. environmental, health, economic, social, psychological, cultural, ethical, political, etc. The report explains how the 2007 Recommendations apply to this type of existing exposure situation, including consideration of the justification and optimisation of protection strategies, and the introduction and application of a reference level to drive the optimisation process. The report also considers practical aspects of the implementation of protection strategies, both by authorities and the affected population. It emphasises the effectiveness of directly involving the affected population and local professionals in the management of the situation, and the responsibility of authorities at both national and local levels to create the conditions and provide the means favouring the involvement and empowerment of the population. The role of radiation monitoring, health surveillance, and the management of contaminated foodstuffs and other commodities is described in this perspective. The Annex summarises past experience of longterm contaminated areas resulting from radiation emergencies and nuclear accidents, including radiological criteria followed in carrying out remediation measures.

Sarcomatoid renal cell carcinoma in a renal transplant recipient

The incidence of transplanted kidneys derived from elderly donors is increasing because of the larger waiting lists and greater age of patients with end-stage renal failure. Compared with young donors, one of the problems is the heightened risk of neoplasm transmission. We report 2 cases of kidney recipients, both of whom developed a sarcomatoid renal cell carcinoma after receiving a kidney transplant from the same 68-year-old male donor, who did not show signs of a neoplasm on a previous abdominal ultrasound or a pretransplant biopsy. The first recipient was a 66-year-old woman who developed a kidney mass with several urologic obstructive complications, tumor dissemination, and death at 9 months after kidney transplantation. The second recipient was a 48-year-old asymptomatic man with normal renal function, who was studied after the results of the first recipient, revealing another renal tumor. Transplant nephrectomy was performed and a peritoneal implant was resected. The patient is alive without evidence of a neoplasm after 18 months. Herein we have discussed the mechanisms of neoplasm transmission in kidney transplantation and possible strategies for its prevention and treatment.

Evaluation of CdZnTe as neutron detector around medical accelerators

The operation of electron linear accelerators (LINACs) and cyclotrons can produce a mixed gamma-neutron field composed of energetic neutrons coming directly from the source and scattered lower energy neutrons. The thermal neutron detection properties of a non-moderated coplanar-grid CdZnTe (CZT) gamma-ray detector close to an 18 MV electron LINAC and an 18 MeV proton cyclotron producing the radioisotope (18)F for positron emission tomography are investigated. The two accelerators are operated at conditions producing similar thermal neutron fluence rates of the order of 10(4) cm(-2) s(-1) at the measurement locations. The counting efficiency of the CZT detector using the prompt 558 keV photopeak following (113)Cd thermal neutron capture is evaluated and a good neutron detection performance is found at the two installations.

VOCs and PAHs emissions from creosote-treated wood in a field storage area

In this study, the emissions of volatile organic compounds (VOCs, in this case aromatic hydrocarbons containing one benzene ring and furans) and polycyclic aromatic hydrocarbons (PAHs) from wood recently treated with creosote are examined. The VOCs and PAHs were identified and quantified in the gas phase. Additionally, the PAHs were quantified in the particulate phase. Glass multi-sorbent tubes (Carbotrap, Carbopack X, Carboxen-569) were used to hold the VOCs. The analysis was performed using automatic thermal desorption (ATD) coupled with capillary gas chromatography/mass spectrometry (GC/MS). PAHs vapours were collected on XAD-2 resin, and particulate matter was collected on glass fibre filters. The PAHs were analysed using GC/MS. The main components of the vapours released from the creosote-treated wood were naphthalene, toluene, m+p-xylene, ethylbenzene, o-xylene, isopropylbenzene, benzene and 2-methylnaphthalene. VOCs emission concentrations ranged from 35 mg m(-3) of air on the day of treatment to 5 mg m(-3) eight days later. PAHs emission concentrations ranged from 28 microg m(-3) of air on the day of treatment to 4 microg m(-3) eight days later. The air concentrations of PAHs in particulate matter were composed predominantly of benzo[b+j]fluoranthene, benzo[a]anthracene, chrysene, fluoranthene, benzo[e]pyrene and 1-methylnaphthalene. The emission concentrations of particulate polycyclic aromatic hydrocarbons varied between 0.2 and 43.5 ng m(-3). Finally, the emission factors of VOCs and PAHs were determined.

Indoor and outdoor BTX levels in Barcelona City metropolitan area and Catalan rural areas

Five aromatic hydrocarbons (benzene, toluene, and three isomeric xylenes) were monitored in indoor and outdoor air of 7 public buildings and 54 private homes, located in Barcelona City metropolitan area and in several rural areas of Catalonia. The sampling was carried out over four periods: spring-summer and winter of 2000, and summer and winter of 2001. Passive ORSA 5 Dräger samplers were used for benzene, toluene, and xylenes (BTX) adsorption. BTX were extracted with carbon disulphide and analysed using a gas chromatograph coupled to a FID detector. In Barcelona metropolitan area the outdoor average concentrations of BTX were 3.5, 34.2, and 31.3 microg/m3 in urban areas, and 1.4, 9.2, and 9.2 microg/m3 in rural areas, respectively. Average indoor air concentrations of BTX were respectively 4.3, 64.8, and 47.6 microg/m3 in urban areas and 5.8, 67.0, and 51.4 microg/m3 in rural areas, respectively. A direct connection between the house and garage was one of the most influential factors for indoor BTX concentrations in rural areas. In urban areas, diffuse traffic sources were the predominant BTX source, slightly influenced by tobacco smoke in indoor air.

Prognostic value of immunohistochemical phenotypes (IP) of 141 operable breast cancer patients (pts) included in phase III trials of adjuvant therapy

21040

Background: Gene expression arrays and IP studies classified breast cancer in three distinct subtypes: basal, HER2/neu and luminal that are associated with different clinical outcomes. Methods: In 141 pts with operable breast cancer, included in phase III trials of adjuvant therapy in our center, immunohistochemical staining was performed on 3μm sections of paraffin blocks, containing tissue-arrays of tumour tissue.A basal phenotype (BP) was defined by negative estrogen receptor (ER) and progesterone receptor (PR) and positive cytokeratin (CK) 5/6 or EGFR immunoreactivity. HER2/neu phenotype as positive c-erb B2 by HercepTest™ and luminal phenotype (LP) by positive ER, PR and CK 7/8 and negative HER-2. Survival curves were calculated by the Kaplan-Meier method. The differences between survivals were estimated using the log rank test. Multivariate Cox regression analysis was used to evaluate any independent prognostic effect of the variables on disease-free survival (DFS). Results: Complete clinical follow-up information was available for 141 pts. The median follow-up period was 52 months (range 1–103 months). During this period, 13.8% pts died from breast cancer and 27.7% pts relapsed. At the time of the primary diagnosis 10.4% of the pts had lymph node negative disease and 89.6% had positive lymph nodes. 50.8% pts received taxane chemotherapy, 7.7% Trastuzumab, 62.3% radiotherapy and 61% pts received hormonotherapy. Positivity for LP was 65.2%, BP 9.9% and Her-2 phenotype 8.5%. 16.3% didn't fit for any of the three subtypes. Median DFS for BP: 24 moths, for LP and Her-2 phenotypes median DFS was not reached. 5 years DFS were; BP: 19%, LP: 63% and Her-2: 56%. Kaplan-Meier survival analyses demonstrated that the presence of a detectable BP was highly significantly associated with a worse DFS compared with the presence of a LP, log rank test (p= 0.0001). Multivariate Cox regression analyses estimated that the prognostic effect of BP in relation to DFS was independent of lymph node, stage and tumor size, HR: 0.12 95% CI (0.05–0.2). Conclusions: We found that expression of BP was associated with poor prognostic in the context of randomized phase III trials.

No significant financial relationships to disclose.

Artificial neural networks technology for neutron spectrometry and dosimetry

Artificial Neural Network Technology has been applied to unfold neutron spectra and to calculate 13 dosimetric quantities using seven count rates from a Bonner Sphere Spectrometer with a (6)LiI(Eu). Two different networks, one for spectrometry and another for dosimetry, were designed. To train and test both networks, 177 neutron spectra from the IAEA compilation were utilised. Spectra were re-binned into 31 energy groups, and the dosimetric quantities were calculated using the MCNP code and the fluence-to-dose conversion coefficients from ICRP 74. Neutron spectra and UTA4 response matrix were used to calculate the expected count rates in the Bonner spectrometer. Spectra and H(10) of (239)PuBe and (241)AmBe were experimentally obtained and compared with those determined with the artificial neural networks.

Water-extended polyester neutron shield for a 252Cf neutron source

A Monte Carlo study to determine the shielding features to neutrons of water-extended polyester was carried out. During calculations, (252)Cf and shielding were modelled and the neutron spectra as well as the H(10) were calculated in four sites. The calculation was extended to include a water shielding, the source in vacuum and in air. Besides neutron shielding characteristics, the Kerma in air due to gammas emitted by (252)Cf and due to capture gamma rays in the shielding were included.

Neutron fluence rate measurement using prompt gamma rays

A gamma ray spectrometer, with a 3('') Ø X 3('') NaI(Tl) detector, with a moderator sphere has been utilised to measure the neutron fluence rate, with this value the H(10) was estimated. When a neutron is captured by the hydrogen-based moderator, a 2.22 MeV prompt gamma ray is produced. In a multichannel analyser the net area under the 2.22 MeV photopeak is proportional to the total neutron fluence rate. The features of this system were determined by a Monte Carlo study that includes 3-, 5- and 10-inches diameter, water and polyethylene moderators and a (239)Pu-Be source. The prompt gamma response was extended to monoenergetic neutron sources. To verify the response, a (239)Pu-Be source in combination with a 10('') polyethylene sphere having a gamma-ray spectrometer with NaI(Tl) was utilised to estimate the neutron fluence rate and the H(10). These results were compared with neutron fluence rate and H(10) obtained using a Bonner sphere spectrometer and with the H(10) measured using a neutron remmeter.

Artificial neural networks in neutron dosimetry

An artificial neural network (ANN) has been designed to obtain neutron doses using only the count rates of a Bonner spheres spectrometer (BSS). Ambient, personal and effective neutron doses were included. One hundred and eighty-one neutron spectra were utilised to calculate the Bonner count rates and the neutron doses. The spectra were transformed from lethargy to energy distribution and were re-binned to 31 energy groups using the MCNP 4C code. Re-binned spectra, UTA4 response matrix and fluence-to-dose coefficients were used to calculate the count rates in the BSS and the doses. Count rates were used as input and the respective doses were used as output during neural network training. Training and testing were carried out in the MATLAB environment. The impact of uncertainties in BSS count rates upon the dose quantities calculated with the ANN was investigated by modifying by +/-5% the BSS count rates used in the training set. The use of ANNs in neutron dosimetry is an alternative procedure that overcomes the drawbacks associated with this ill-conditioned problem.

Effects of cinnarizine, a calcium antagonist that produces human parkinsonism, in parkin knock out mice

Cinnarizine, a calcium antagonist that produces parkinsonism in humans, induces behavioural changes such as alopecia, buco-lingual dyskinesia and reduction of motor activity in female parkin knock out (PK-KO) mice but not in wild-type (WT) controls. PK-KO mice have high striatal dopamine levels and increased dopamine metabolism in spite of low reduced tyrosine hydroxylase protein. Cinnarizine, which blocks dopamine receptors and increases dopamine release, further increased dopamine metabolism. PK-KO mice increased GSH levels as a compensatory mechanism against enhanced free radical production related to acceleration of dopamine turnover. Neuronal markers, such as beta-tubulin slightly increased in PK-KO and furthermore with cinnarizine. Astroglial markers were decreased in PK-KO mice, and this effect was potentiated by cinnarizine, suggesting abnormal glia in these animals. Microglia was hyperactivated in PK-KO midbrain, suggesting inflammation in these animals. Proapoptotic proteins were increased by cinnarizine and, to a lesser extent, in PK-KO mice. Our data indicate that mutation of parkin is a risk factor for drug-induced parkinsonism.

[Embolization of non-functioning renal allograft: efficacy and control of systemic inflammation]

BACKGROUND

The graft intolerance syndrome (fever, pain, haematuria) may lead to a chronic inflammatory disease, with cardiovascular repercussion. Nephrectomy is considered the classical treatment of these cases but nowadays renal vascular embolization has been suggested as a possible alternative treatment. The present study concerns seven cases trated with renal vascular embolization in our hospital summarizing data of graft intolerance syndrome and the chronic inflammatory disease.

MATERIAL AND METHODS

Between january 2000 and december 2003 seven renal vascular embolization were performed in nonfunctioning renal allograft. The procedure was made with calibrated particles of 300-500micron. Data about complications related to the technique the same as analitic inflammatory parameters before and after treatment (CRP, ferritin, serum albumin, hemoglobin, erythropoietin) were registered.

RESULTS

The patients were two men and five women, with median age of 39,7 +/- 8,8 years. The period beween the dialysis and the embolization was of 10,0 +/-8,2 months. Comparing the perion of admission in the hospital due to nephrectomy which was of 17,86+/-4,41 days, the period because of embolization was shorter, being 8,14 +/- 4,53 days. All analitic parameters studied, clearly improved after embolization with decrease of ferritin and CRP, increase of albumin and better hemoglobin level with lower erythropoietin dose. In five of the seven patients there was no renal captation with CT or gammagraphy. Four patients presented a postembolization syndrome, but no other important complication was registered. Neither reembolization nor renal nephrectomy was neccesary in any of the seven cases.

CONCLUSION

Percutaneous renal embolization is a simple, easy, safety and effective technique that must be considered as an alternative treatment to nephrectomy, resolving the chronic inflammatory disease secondary to the graft intolerance syndrome.

Characteristics of the neutron field of the facility at DIN-UPM

A new source facility (241Am-Be) has been installed in a bunker-type room of large dimensions. To characterise the neutron fields in the facility, detailed calculations have been made with MCNP-4C, showing the different components of the neutron radiation reaching the reference points (direct, inscattered, backscattered). The contribution from neutrons scattered in the walls to the total ambient dose equivalent remains reasonably low (<10%) in the reference points. Additionally, spectra measurements have been performed with a Bonner spheres spectrometer with a 6LiI(Eu) scintillator (0.4 phi x 0.4 cm2), UTA4 response matrix and BUNKIUT unfolding code. The calculated and experimentally obtained spectra are compared, with small differences found in the epithermal and thermal region, attributable to the concrete composition used in the calculations. The H*(10) rate has been determined from the spectra, and then compared to the reading of an active dosemeter (LB6411), with differences found lower than 8%.

[Primary amyloidosis associated to severe factor X deficiency]

Amyloidosis is a systemic disease characterized by generalized deposition of beta-organized proteic fibrillar material with green birefringence under polarized light, in different tissues and organs, the most frequent kidney, liver and heart, with important clinical repercussion. Primary or AL amyloidosis is the most common subtype of amyloidosis (1), confirmed by biopsy-proved amyloid deposition in abdominal fat pad, rectum, kidney or liver, if necessary, in which fragments of monoclonal light chains are deposited. Cases with factor X (Stuart factor) of coagulation deficiency associated are described, due to adsorption of this factor to amyloid fibrills. Normally, evolution is fatal, with only few months of survival. We report a case of primary amyloidosis with nephrotic syndrome, severe factor X deficiency (without bleeding complications), possible heart affection and short-term good response to chemotherapic treatment.

[Influence of early or late referral to nephrologist over morbidity and mortality in hemodialysis]

OBJECTIVE

We studied the influence of early vs late referral to nephrologist of patients with chronic renal failure over clinical situation at the onset of hemodialysis and outcome.

SUBJECTS AND METHODS

From january 1994 to december 1998, 139 patients started hemodialysis for end-stage renal disease at the Hospital General de Albacete, all of them included in the study and clinical follow-up concluded in december 2001. Patients with rapidly progressive glomerulonephritis were excluded. Early (ER) and late referral (LR) were defined by the time of first nephrology encounter greater than or less than 6 months respectively, before iniciation of hemodialysis.

RESULTS

106 patients (76.25%) were referred early; mean follow-up time 6.3 +/- 4.5 years. 33 patients (23.74%) had late referral, follow-up time was less then six months, 18 patients were followed during less than 4 weeks. There were no differences in demographic data and comorbid conditions between LR and ER patients (age, cardiac and vascular disease, diabetes, neoplasia...). Mean plasma concentration of creatinine and urea was significantly greater, whereas hematocrit and albumin were less in the LRA than the ER group. Emergency dialysis through central vein catheterisation was more frequent in the LR group. Number of admissions and duration of hospital stay were higher in the LR group. No significant differences in nutrition, dialysis doses or anemia were found between the two groups after 6 and 12 months of hemodialysis. Long term outcome was similar in both groups: no significant differences were found in percentage of patients transplanted or deceased after 3 years of treatment. Survival analysis failed to show a difference between ER and LR groups (mean survival time was 73.6 +/- 4.3 months and 73.0 +/- 6 months respectively).

CONCLUSION

Late referral to the nephrologist is associated with increased early morbidity vs early referral, although long term outcome is not worse if predialysis comorbid conditions are comparable and dialysis care achieve equal results in dialysis doses, nutrition and anemia in both groups in the first months of treatment. Improvement of outcome of patients referred early to the nephrologist will depend on the adoption of preventive measures over comorbidity factors that should be applied in early stages of renal disease.