Photodegradative fate and potential phototoxic products of bromocarbazoles and chlorocarbazoles in water.

Bromocarbazoles and chlorocarbazoles are emerging environmental contaminants that have been reported to be persistent and possessing dioxin-like toxicity; however, their photodegradative fate in water is unknown. The photodegradation of 3-bromocarbazole, 3-chlorocarbazole, and 3,6-dichlorocarbazole was determined in ultrapure water. They proceeded by direct photolysis and followed first-order kinetics. The rate constants (k) were 0.4838, 0.3454, and 0.4422 h-1 corresponding to half-lives (t 1/2) 1.81, 2.01, and 1.62, while the quantum yields (Ф) were 0.232, 0.180, and 0.295 respectively. The maximum wavelengths of absorption (λ max) were in the near ultraviolet region (295, 296, 299, and 301 nm) implying these compounds are likely to degrade slowly under sunlight in natural aquatic environment. The molar extinction coefficients (ε) determined in acetonitrile were 18,573, 17,028, 13,385, and 14,010 L mol-1 cm-1, respectively, the latter being 3,6-dibromocarbazole. A bathochromic shift was observed with halogen addition on their respective mono-substituted congeners. Bromocarbazoles were observed to degrade faster in water than chlorocarbazoles. In addition, photodegradation was estimated to proceed faster in summer than in winter, in natural water system at 50° N latitude. In the absence of light, hydrolytic degradation occurred but proceeded very slowly. Hexahydroxybenzene and trihydroxycarbazole were positively identified as the likely photoproducts with the former being a known toxic compound. Dehalogenation, oxidative cleavage, hydroxylation, and hydrolysis are suggested as the major photodegradation mechanisms in water, yielding phototoxic products that may be of enhanced toxicity than the parent compounds.

Adapting current model with field data of related performance reference compounds in passive samplers to accurately monitor hydrophobic organic compounds in aqueous media.

Performance reference compounds (PRCs) are neutral organic compounds, introduced in a passive sampler prior deployment for the assessment of in situ sampling rate. In this study, evaluation of in situ sampling rates of 16 13C-PAH-PRCs with moderate and high hydrophobicity was established to provide an overall correction factor for variations in virtual organism (VO) uptake rates of the analytes of interest. In situ sampling rate was compared to an empirical model during sampling campaign in 2011 with VO in 12 different sites along the Three Gorges Reservoir (TGR) in China. A discrepancy was observed for high hydrophobic compounds with log K ow ranging from 5.18 to 6.63 where ΣPAH concentration in TGR from Huckins model (305,624 pg/L) was resulted to be roughly 2-fold higher than the alternative procedure (182,292 pg/L). A relationship between in situ sampling rates of the 16 13C-PAH-PRCs (Rs, PRC ) and log K ow was set up to allow then calculation of analyte sampling rate Rs analyte (N) of various organic pollutants with log K ow  ≤ 6.63.

Polycyclic aromatic hydrocarbons (PAHs) determined by pine needles and semipermeable membrane devices along an altitude profile in Taurus Mountains, Turkey.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed at different altitudes of Taurus Mountains in semipermeable membrane devices (SPMD) and in half-, one-and-a-half-, and two-and-a-half-year-old pine needles. SPMDs were deployed for three different exposure periods: March to September (Summer), September to March (Winter), and March to March (whole year) at eight sites where needle samples were collected. The values of PAHs in needles were between 4.4 to 6066 pg g/fw in half-year-old, 7.2 to 111,115 pg g/fw in 1.5-year-old, and 9.7 to 85,335 pg g/fw in 2.5-year-old needles. Mass of PAHs collected by SPMDs varied from

Depth profile of persistent and emerging organic pollutants upstream of the Three Gorges Dam gathered in 2012/2013.

Persistent and emerging organic pollutants were sampled in September 2012 and 2013 at a sampling site in front of the Three Gorges Dam near Maoping (China) in a water depth between 11 and 61 m to generate a depth profile of analytes. A novel compact water sampling system with self-packed glass cartridges was employed for the on-site enrichment of approximately 300 L of water per sample to enable the detection of low analytes levels in the picogram per liter-scale in the large water body. The overall performance of the sampling system was acceptable for the qualitative detection of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), perfluoroalkylic acids (PFAAs), pharmaceutical residues and polar pesticides. Strongly particle-associated analytes like PAHs and PCBs resided mainly in the glass wool filter of the sampling system, whereas all other compounds have mainly been enriched on the XAD-resin of the self-packed glass cartridges. The sampling results revealed qualitative information on the presence, depth distribution and origin of the investigated compounds. Although the depth profile of PAHs, PCBs, OCPs, and PFAAs appeared to be homogeneous, pharmaceuticals and polar pesticides were detected in distinct different patterns with water depth. Source analysis with diagnostic ratios for PAHs revealed their origin to be pyrogenic (burning of coal, wood and grass). In contrast, most PCBs and OCPs had to be regarded as legacy pollutants which have been released into the environment in former times and still remain present due to their persistence. The abundance of emerging organic pollutants could be confirmed, and their most abundant compounds could be identified as perfluorooctanoic acid, diclofenac and atrazine among investigated PFAAs, pharmaceuticals and polar pesticides, respectively.

Concentrations and mass fluxes estimation of organochlorine pesticides in Three Gorges Reservoir with virtual organisms using in situ PRC-based sampling rate.

Organochlorine pesticides (OCP) are widely distributed environmental pollutants. Due to their persistence and toxicity, it is important to know their fluxes and spatial and temporal distribution in the environment. In this study, a new procedure to estimate OCP concentration based on a set of performance reference compounds (PRCs) was used. Their occurrence and mass fluxes were assessed on a regional scale ranging from Chonqging to Maoping in Three Gorges Reservoir (TGR) as part of Yangtze River. The results are based on three sampling campaigns in 2009 (twice) and 2011. Due to different factors, the measured concentrations varied from 410 to 1418 pg/L. The highest total OCP concentration was localized in Wanzhou while the lowest was downstream Maoping near the Three Gorges Dam (TGD). The highest load of OCP mass fluxes was observed at Wanhzou with 9.6 mg/s and the lowest load at Maoping with 2.97 mg/s. Studies at Maoping show an increase in OCP water concentration from 2009 to 2012. Comparison between free dissolved OCP water concentration and total OCP water concentration in TGR 2009, 2011 and 2012 show a slight variation, indicating the important role of dilution in the OCP removal process in TGR.

PAHs and PCBs accumulated by SPMD-based virtual organisms and feral fish in Three Gorges Reservoir, China.

Polycyclic aromatic hydrocarbon (PAHs) and polychlorinated biphenyls (PCBs) accumulated by semipermeable membrane device (SPMD)-based virtual organisms (VOs) and local feral fish were studied in Three Gorges Reservoir (TGR), China. VOs were deployed at seven sites in TGR for two periods in 2009 and 5 species of fish with different living habitats and feeding habits collected in the same periods from two counties in TGR. The concentration and profile of PAHs and PCBs in fish were quite different from those in VOs. Most high-molecular-weight-PAHs were detected in VOs, while they were undetected in fish. Most PCBs were undetected in VOs, while most of them were detected in fish. Low-molecular-weight-PAHs were predominant contaminants of PAHs and non-dioxin-like-PCBs were the main PCBs in fish. The levels of PAHs and PCBs in the few fish samples were low and were not of concern based on chemical contaminant limits of non-carcinogenic effect.

Organochlorine pesticides accumulated by SPMD-based virtual organisms and feral fish in Three Gorges Reservoir, China.

Organochlorine pesticides (OCPs) accumulated by semipermeable membrane device (SPMD) -based virtual organisms (VOs) and local feral fish were studied in Three Gorges Reservoir (TGR), China. VOs were deployed at seven sites in TGR for two periods in 2009 and 5 species of fish with different living habitats and feeding habits collected in the same periods from two counties in TGR. 28 OCPs were analyzed and the concentration and profile of OCPs in fish were quite different from those in VOs. The lipid-based concentrations of OCPs in fish ranged from 225.7 ng/g lw to 1996.4 ng/g lw which were much higher than those in VOs which ranged from 17.3 to 112.4 ng/g lw. Dichlorodiphenyltrichloroethanes (DDTs) were the prevalent OCPs in the investigated fish, while hexachlorobenzene (HCB) was the dominant compound in VOs. DDT in the few fish sample analyzed was not of concern based on chemical contaminant limits of non-carcinogenic effect.

Persistence and dioxin-like toxicity of carbazole and chlorocarbazoles in soil.

Halogenated carbazoles have recently been detected in soil and water samples, but their environmental effects and fate are unknown. Eighty-four soil samples obtained from a site with no recorded history of pollution were used to assess the persistence and dioxin-like toxicity of carbazole and chlorocarbazoles in soil under controlled conditions for 15 months. Soil samples were divided into two temperature conditions, 15 and 20 °C, both under fluctuating soil moisture conditions comprising 19 and 44 drying-rewetting cycles, respectively. This was characterized by natural water loss by evaporation and rewetting to -15 kPa. Accelerated solvent extraction (ASE) and cleanup were performed after incubation. Identification and quantification were done using high-resolution gas chromatogram/mass spectrometer (HRGC/MS), while dioxin-like toxicity was determined by ethoxyresorufin-O-deethylase (EROD) induction in H4IIA rat hepatoma cells assay and multidimensional quantitative structure-activity relationships (mQSAR) modelling. Carbazole, 3-chlorocarbazole and 3,6-dichlorocarbazole were detected including trichlorocarbazole not previously reported in soils. Carbazole and 3-chlorocarbazole showed significant dissipation at 15 °C but not at 20 °C incubating conditions indicating that low temperature could be suitable for dissipation of carbazole and chlorocarbazoles. 3,6-Dichlorocarbazole was resistant at both conditions. Trichlorocarbazole however exhibited a tendency to increase in concentration with time. 3-Chlorocarbazole, 3,6-dibromocarbazole and selected soil extracts exhibited EROD activity. Dioxin-like toxicity did not decrease significantly with time, whereas the sum chlorocarbazole toxic equivalence concentrations (∑TEQ) did not contribute significantly to the soil assay dioxin-like toxicity equivalent concentrations (TCDD-EQ). Carbazole and chlorocarbazoles are persistent with the latter also toxic in natural conditions.

Water exposure assessment of aryl hydrocarbon receptor agonists in Three Gorges Reservoir, China using SPMD-based virtual organisms.

SPMD-based virtual organisms (VOs) were deployed at five to eight sites in the Three Gorges Reservoir (TGR), China for five periods in 2008, 2009 and 2011. The water exposure of aryl hydrocarbon receptor (AhR) agonists was assessed by the VOs. The chosen bioassay response for the extracts of the VOs, the induction of 7-ethoxyresorufin-O-deethylase (EROD) was assayed using a rat hepatoma cell line (H4IIE). The results show that the extracts from the VOs could induce AhR activity significantly, whereas the chemically derived 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalent (TEQcal) accounted for <11% of the observed AhR responses (TEQbio). Unidentified AhR-active compounds represented a greater proportion of the TCDD equivalent in VOs from TGR. High TEQbio value in diluted extract and low TEQbio in concentrated extract of the same sample was observed suggesting potential non-additive effects in the mixture. The levels of AhR agonists in VOs from upstream TGR were in general higher than those from downstream reservoir, indicating urbanization effect on AhR agonist pollution. The temporal variation showed that levels of AhR agonists in 2009 and 2011 were higher than those in 2008, and the potential non-additive effects in the area close to the dam were also obviously higher in 2009 and 2011 than in 2008, indicating big changes in the composition of pollutants in the area after water level reached a maximum of 175 m. Although the aqueous concentration of AhR agonists of 0.8-4.8 pg TCDDL(-1) in TGR was not alarming, the tendency of accumulating high concentration of AhR agonists in VO lipid and existence of possible synergism or antagonism in the water may exhibit a potential hazard to local biota being exposed to AhR agonists.

Combined chemical and toxicological long-term monitoring for AhR agonists with SPMD-based virtual organisms in drinking water Danjiangkou Reservoir, China.

SPMD-based virtual organisms (VOs) were employed for time-integrating, long-term sampling combined biological and chemical analyses for exposure assessment of hydrophobic organic pollutants (HOPs) in a drinking water reservoir, China. The SPMDs were deployed at four and five sites in the Danjiangkou (DJK) reservoir over two periods of 26 and 31 d to sequester the hydrophobic contaminants in water. The chosen bioassay response for the extracts of the SPMDs, the induction of 7-ethoxyresorufin-o-deethylase (EROD) was assayed using a rat hepatoma cell line (H4IIE). The known aryl hydrocarbon receptor (AhR) agonists PAHs and PCBs were analyzed by HRGC/HRMS instrument. The cause-effect relationship between the observed AhR activities and chemical concentrations of detected AhR agonists was examined. The results show that the extracts from the SPMD samples could induce AhR activity significantly, whereas the chemically derived 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalent (TEQcal) was not correlated with the bioassay-derived TCDD equivalent (TEQbio). The known AhR agonists could only account for 2-10% of the observed AhR responses among which the contribution of PCBs could almost be neglected. Unidentified AhR-active compounds represented a greater proportion of the TCDD equivalent (TCDD-EQ) in SPMD samples from DJK. Based on the first assessment, the VO followed by the combination of chemical and biological analyses emerges as a resource efficient water monitoring device in ecotoxicological assessment for toxicologically relevant compounds which are readily available for uptake by resident aquatic biota in drinking water resources.

Catecholamine levels in groundwater and stream amphipods and their response to temperature stress.

Temperature stress in invertebrates is known to be reflected by changes in catecholamine levels. However, the mechanisms of stress response are not fully understood. Groundwater and surface water amphipods are expected to be differently adapted to temperature elevations due to the different temperature regimes in their habitats and consequently, show a different stress response. No data have been published so far regarding the effects of stress on catecholamine patterns in groundwater invertebrates and accordingly, comparisons with surface water fauna are also missing. In this study, we compared the average catecholamine levels in two taxonomically related amphipod species: Niphargus inopinatus, living in groundwater with constant water temperatures throughout the year, and Gammarus pulex, a surface water stream amphipod frequently exposed to diurnal and seasonal temperature fluctuations. Furthermore, we tracked the immediate changes in whole-animal catecholamine levels in response to heat stress in both species. Pronounced differences in the catecholamine levels of the two species became apparent, with the average dopamine (DA) level of N. inopinatus being almost 1000 times higher than that in G. pulex. The noradrenaline (NA) concentrations in N. inopinatus were on average two orders of magnitude higher than in G. pulex, and for adrenaline (A), the difference constituted one order of magnitude. When exposed to short-term heat stress, both species showed a response in terms of catecholamine levels, but the observed patterns were different. In N. inopinatus, temperature stress was reflected by the appearance of adrenaline, while in G. pulex a significant increase in noradrenaline levels occurred in the treatment with the highest temperature elevation.

Detection of catecholamines in single specimens of groundwater amphipods.

Catecholamines play essential roles in several physiological processes in vertebrates as well as in invertebrates. While several studies have shown the presence of these substances in surface water invertebrates, their occurrence in groundwater fauna is unproven. In the present study, the presence of different catecholamines (i.e., noradrenaline, adrenaline, and dopamine) in individual specimens of groundwater amphipods of the genus Niphargus (mostly Niphargus inopinatus) was investigated via two independent analytical methods: HPLC/EcD and UPLC/TOF-MS. Mean values for catecholamine levels were 533 pg mg(-1) fresh weight for noradrenaline, 314 pg mg(-1) for adrenaline, and 16.4 ng mg(-1) for dopamine. The optimized protocol allowed the detection of CAs in single organisms of less than 1 mg fresh weight. Catecholamine concentration patterns in groundwater invertebrates are briefly discussed here with respect to their evolutionary adaptation to an environmentally stable, energy-poor habitat.

Method for toxicity test of titanium dioxide nanoparticles in ciliate protozoan Tetrahymena.

Titanium dioxide (TiO2) nanoparticles have a high surface-to-mass ratio and rapidly aggregate in water causing great difficulties for toxicity test exposed to aquatic organisms or other cell lines. This study uses a cell viability kit for routine toxicity test of TiO2 as well as other nanoparticles which accumulate in the aquatic environment. Tetrahymena immediately endocytoses TiO2 nanoparticles and stores them in food vacuoles until the particles undergo exocytosis as larger aggregates. However, during the process of endocytosis and exocytosis, TiO2 particles interfere with cell growth and consequently induce acute toxicity. It exerted high cell growth inhibition at 20 h incubation and induces significant cytotoxic effects. Surprisingly, the effect of TiO2 decreases at 40 h incubation, due to the recovery of cell growth and reduction of the cytotoxicity of the particles.

Simultaneous monitoring of PCB profiles in the urban air of Dalian, China with active and passive samplings.

The concentration of polychlorinated biphenyls (PCBs) in the urban air of Dalian, China was monitored from November 2009 to October 2010 with active high-volume sampler and semipermeable membrane device (SPMD) passive sampler. The concentration of PCBs (particle + gas) (SigmaPCBs) ranged from 18.6 to 91.0 pg/m3, with an average of 50.9 pg/m3, and the most abundant dioxin-like PCB (DL-PCBs) was PCB118. The WHO-TEQ values of DL-PCBs were 3.6-22.1 fg/m3, with an average of 8.5 fg/m3, and PCB126 was the maximum contributor to SigmaTEQ. There was a much larger amount of PCBs in the gas phase than in the particulate phase. The dominant PCB components were lower and middle molecular weight PCBs. With increasing chlorination level, the concentration of the PCB congeners in the air decreased. The gas-particulate partitioning of PCBs was different for the four seasons. The gas-particulate partitioning coefficients (logKp) vs. subcooled liquid vapor pressures (logP(L)0) of PCBs had reasonable correlations for different sampling sites and seasons. The absorption mechanism contributed more to the gas-particulate partitioning process than adsorption. Correlation analysis of meteorological parameters with the concentration of PCBs was conducted using SPSS packages. The ambient temperature and atmospheric pressure were important factors influencing the concentration of PCBs in the air. The distribution pattern of the congeners of PCBs and the dominant contributors to DL-PCBs and TEQ in active samples and SPMDs passive samples were similar. SPMD mainly sequestrated gas phase PCBs.

Temporal variation and spatial distribution of PAH in water of Three Gorges Reservoir during the complete impoundment period.

Bioavailable concentrations of polycyclic aromatic hydrocarbons (PAHs) were investigated in water of Three Gorges Reservoir (TGR) using semipermeable membrane devices during the period of completely impounding water. ∑PAH concentrations in water of TGR in the period of completely impounding water were 15-381 ng L(-1). ∑PAH concentrations increased from town or counties to big industrialized cities in TGR, indicating urbanization effects on PAH pollution in the water. Tributaries in TGR have a certain contribution of PAH pollution to the mainstream of Yangtze River and their pollution could not be neglected. An obvious decrease of PAH concentration was observed after 175-m water impounding in 2011 in TGR. Several factors may account for this decrease, including execution of comprehensive treatment and management measures in TGR, less rainfall in 2011, and sedimentation effect caused by the dam. Passive sampling method has been successfully applied in the investigation of trace PAH in water of TGR and proved to be a useful and efficient tool for the management and sustainable development of the big reservoir. The results of the study provide valuable information about PAH pollution in the whole reservoir including some tributaries, and the pollution status is dynamically related with human activities. Therefore, PAH could be used as a marker compound or indicator in the network monitoring system to surveil and trace the pollution status in TGR.

Impacts of climate-induced changes on the distribution of pesticides residues in water and sediment of Lake Naivasha, Kenya.

This study reports evidence of increased chlorpyrifos contamination in sediment and water in Lake Naivasha following its intensive application in the horticultural farms in the catchment area. Analytical results show that levels of chlorpyrifos residues were influenced by climate-induced rainfall pattern with higher levels reported during period of heavy precipitation with significant decrease during low rainfall. On average, the levels ranged between 14.8 and 32.8 ng g(-1) in sediment during rainy season compared to a range of 8.5-16.6 ng g(-1) in the dry season. Additionally, the mean concentration of chlorpyrifos in water ranged between 8.61 and 22.4 µg L(-1) during rainy season and below detection limit (bdl) -13.6 µg L(-1) in dry season as quantified by enzyme-linked immunosorbent assay. Meanwhile, independent t test analysis indicated that there was significant difference in concentration at p ≤ 0.05 between the seasons with respect to sediment and water samples. This demonstrated that climate-induced variations had considerable influence on contamination. While diazinon and carbofuran were equally applied intensively, their levels were below the detection limit in the all the samples analyzed. ELISA results were validated by the capillary-HPLC photodiode-array detector instrument analysis, and statistical comparison showed no significant difference between them. It was evident that chlorpyrifos residues determination in water and sediment by ELISA can be a useful strategy in environmental management and monitoring program, and a complimentary analytical tool to high performance liquid chromatography. Levels of chlorpyrifos detected in sediment and water were found to exceed recommended criteria for protection of aquatic life and preservation of water quality and may be hazardous if not regularly monitored.

Human exposure to fluorotelomer alcohols, perfluorooctane sulfonate and perfluorooctanoate via house dust in Bavaria, Germany.

This study aimed at investigating the presence and distribution of fluorotelomer alcohols (FTOHs), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in house dust to evaluate human exposure to these compounds via dust ingestion. 31 house dust samples were collected from Bavaria, Germany and analyzed for 4:2, 6:2, 8:2 and 10:2 FTOH, PFOS and PFOA. PFOA was the dominant compound in 79% of the dust samples, followed by PFOS and 8:2 FTOH, while 4:2 FTOH was not detected in any samples. The total concentration of per- and polyfluorinated compounds (PFCs) varied from 32.2 to 2456 ng/g. In addition, the total ingestion rate for PFCs was 0.4-135 ng/d for adults and 5.1-246 ng/d for toddlers, and the highest 8:2 FTOH-based PFOA intake via indoor dust was 0.24 ng/d for adults and 0.44 ng/d for toddlers. Overall, the results of this study demonstrate that dust ingestion is a minor pathway for human exposure to these PFCs; the PFC ingestion via indoor dust is generally low, and only under a worst scenario high intakes have to be expected for toddlers.

Chemical- and effect-oriented exposomics: Three Gorges Reservoir (TGR).

Exposomic studies of the rapidly changing environment of the Three Gorges Reservoir (TGR) after its impounding is elaborated as a novel field of human and environmental research. Molecular exposomics is focused on the measure of all exposures to molecules and especially persistent organic pollutants-like compounds are of emerging interest due to their lifetime existence in the environment and humans. Theoretical considerations in general and particular for the TGR are deduced and presented using quantitative approaches for this research field. Since exposomics is strongly time-dependent, a theory is presented to link extension of exposure, time, and related effects. Similarity to the first law of thermodynamics is outlined. On top of this, the integrated use of biomarkers is presented employing chemical analysis for biomarkers of exposure and effects, biomarkers in vivo, in vitro approaches and the link between chemical mixtures, and the onset of disease and lethality. Besides real organisms, also virtual organisms are favored to act as well-defined sub-compartments such as fat of biota and with respect to time of exposure. Exposomics is the perspective of risk evaluation and chronic exposures in the running century. It needs novel theories, approaches, and integrated action between medical and environmental disciplines. The existing knowledge about molecular stressors has to be assembled and put into a context especially with respect not only to time resp. lifetime exposure of humans but also eco-toxicological findings by using highly conserved phylogenetic mechanisms to enable links between human and risks of environmental biota. The TGR is a good example not only to employ biomonitoring of real but also virtual organisms due to the lack of established ecotopes in this changing environment so far. Progress in understanding long-term risks requires a proper theory as well as novel tools such as virtual organisms. On top, multidisciplinary approaches and the utilization of existing knowledge about the exposure of the environment and humans have to be merged and directed into mutual concepts. Effect-oriented and chemical analysis must be designed time-oriented to determine lifetime exposures of mankind and nature. Perspectively, a first attempt about exposomic theory and concepts is proposed and has to be developed experimentally further enclosing virtual besides of real organisms and compartments. Environmental and human exposomics have to be considered as a unified global issue in order to effectively utilize their mutual existing knowledge most effectively. The TGR is a challenging model system aiming this objective.

Live surgery in neurosurgical training courses: essential infrastructure and technical set-up.

BACKGROUND: Training courses in neurosurgery are essential educational elements of residency. Teaching methods vary due to cultural differences, monetary restrictions and infrastructure conditions. Anatomical dissection courses combined with annotated live surgeries performed by senior surgeons have proved to be best accepted by students. OBJECTIVE: In this technical note, we provide detailed information about the necessary requirements, resources and optimal performance of live surgeries in neurosurgical training courses. METHODS AND RESULTS: From 2007 to 2012, 12 neurosurgical training courses with live surgeries were organised at the Department of Neurosurgery. Here, we share our experience and report the essential set-up for these courses. Our department organised seven skull base, four cervical spine and one spinal cord stimulation hands-on dissection course with live surgeries. The course structure included lectures, cadaver dissections and live surgeries. The technical set-up included video transmission via an IP-based network with fibreglass backbone between the operating theatre (OR) and lecture room. During surgery, bidirectional discussions offered the participants the ability to interject and ask questions. Important issues included the careful selection of live operated patients with clearly presented pathology for the didactic cases used to demonstrate the technique. A live surgery should include the entire procedure: intraoperative set-up, positioning, anaesthesiological procedures and handling of intraoperative situations. CONCLUSION: A professionally prepared step-by-step educational program including surgical anatomy, cadaver dissection and live surgeries with online discussion offers a high level of training and enriches both the participants and instructors.