Fecal Microorganisms Research Articles

Widespread microbiological groundwater contamination in the South-eastern Salento (Puglia-Italy)

In the Salento peninsula (Puglia Region, South-East Italy), underground waters are a fundamental resource for the population because they constitute the principal reservoir for drinking water and irrigation. They are, however, affected by overexploitation. The risk factors in the Salento arise mainly from anthropic activities, especially tourism and agriculture (leaking wells, sewage and inadequate waste disposal procedures). The Southern Salento is recognized to be at high risk of pathologies characterised by oral-faecal transmission. From 2001 to 2009 the incidence of typhoid fever in the Salento was 12.11/100,000 inhabitants as against 2.91 in Italy. Enteritis caused by rotaviruses is an important cause of hospitalization of paediatric-aged children in the Salento, with high social costs. An effective monitoring system for the conservation and management of water bodies and the protection of public health is therefore fundamental. The present study sought to determine the microbiological and chemical-physical quality of groundwater in the Salento and to analyse the factors associated with contamination. The results indicated widespread pollution from salt and microbial contamination. Contamination from faecal microorganisms posed a significant risk of human infection in 100% of samples. Furthermore, the water was unsuitable even for irrigation in a high percentage of cases (31.8%), which is of considerable significance given that agriculture is one of the most important economic activities in the area under study. The high salt concentration was probably due to excessive extraction of water for intensive irrigation, especially in summer. Under these circumstances, some of mitigation activity is necessary. Furthermore, it would be advisable to decrease the pollution load from anthropic activities in the territory and to reduce water consumption in order to conserve groundwater resources especially.

Foreword: Pathogens and Fecal Indicators in Groundwater

Introduction Groundwater usually has lower concentrations of pathogens and other fecal microorganisms than surface water, because of the natural tendency for these organisms to be removed by straining through small pore throats, attachment to mineral surfaces, or inactivation/die-off during transport (McDowell-Boyer et al. 1986). However, the degree of microbial removal in soils and aquifers can vary greatly, depending on factors such as material type, depth to water table, presence or absence of confining layers, flow rate, proximity to fecal sources, fecal concentration in recharge water, and the types of fecal microorganisms present (viruses, bacteria, and protozoa). As a result, in some geologic settings groundwater often contains fecal microorganisms including pathogens. For example, a report from the U.S. Geological Survey on water quality in the upper Tennessee River Basin, where karst is the dominant aquifer type, indicated that all the springs and about one-third of the wells surveyed contained Escherichia coli, presumably from fecal sources (Hampson et al. 2000). Contaminated groundwater was implicated as the cause of just over half of the disease outbreaks related to drinking water in the United States over the period 1971 to 2006 (Craun et al. 2010). Approximately 30% of the outbreaks were related to untreated groundwater and an additional 22% were related to inadequate or interrupted treatment of groundwater. Surveys by various federal and state agencies in the United States indicate that microbial water quality of aquifers is widely variable, which was a motivating factor behind the development of the “Ground Water Rule” that set new regulations and guidelines for monitoring and treatment of groundwater (USEPA 2006a, 2006b). Many

Antimicrobial resistance of heterotrophic bacteria in sewage-contaminated rivers

Sewage-contaminated rivers are ecosystems deeply disturbed by human activity due to the release of heavy metals, organic pollutants and pharmaceuticals as well as faecal and pathogenic micro-organisms, which coexist with the autochthonous microbial population. In this study, we compared the percentage of resistance in faecal and heterotrophic bacteria in rivers with different degrees of sewage pollution. As a matter of fact, no correlation was found neither between the degree of sewage pollution and the percentage of antimicrobial resistant heterotrophic bacteria nor between the number of resistant faecal bacteria and that of resistant heterotrophic bacteria. Most of the resistant isolates from the Zenne river downstream Brussels were multi-resistant and the resistance patterns were similar among the strains of each phylogenetic group. The total microbial community in this polluted river (as evaluated through a 16S rRNA gene clone library analysis) appeared to be dominated by the phyla Proteobacteria and Bacteroidetes while the phylum TM7 was the third most represented.

Comparison between the photocatalytic inactivation of Gram-positive E. faecalis and Gram-negative E. coli faecal contamination indicator microorganisms

Photocatalytic inactivation of two different faecal contamination indicator microorganisms, the Gram-negative Escherichia coli and the Gram-positive Enterococcus faecalis, has been studied using TiO2 in suspension and immobilized onto the reactor wall. The effect of the main variables of the photocatalytic process on the disinfection efficiency has been analyzed using deionized water and a simulated effluent of wastewater treatment plant (WTP). Noticeable differences were observed between both types of bacteria during photolytic experiments without TiO2 in deionized water, probably due to the higher sensibility of E. coli to the osmotic stress, which leads to a higher cell membrane permeability and consequently a lower amount of hydroxyl radical attacks required to overcome the inactivation threshold. In contrast, despite their structural differences, Gram-positive and Gram-negative bacteria seem to follow the same inactivation mechanism, showing no significant differences in the experiments carried out with TiO2 in suspension either in deionized water or in WTP simulated effluent, with similar responses to changes in the concentration of catalysts and irradiation power (both variables involved in the hydroxyl radical generation). Similar results are observed using immobilized TiO2 in deionized water, although disinfection experiments of WTP simulated effluent using immobilized TiO2 showed much longer initial delays before the beginning of the inactivation for E. faecalis, suggesting a critical effect of the water composition of the bacteria-catalyst interaction. In any case, the irradiation time required to achieved the inactivation below the experimental bacterial detection limit is similar for both microorganisms, and experiments with mixtures of E. faecalis and E. coli in WTP simulated effluent show no significant differences. Therefore, it can be concluded that the results of photocatalytic disinfection experiments using E. coli as model bacteria could be reasonably extrapolated to other types of bacteria or bacterial mixtures.

Cladophora in the Great Lakes: impacts on beach water quality and human health

Cladophora in the Great Lakes grows rapidly during the warm summer months, detaches, and becomes free-floating mats as a result of environmental conditions, eventually becoming stranded on recreational beaches. Cladophora provides protection and nutrients, which allow enteric bacteria such as Escherichia coli, enterococci, Shigella, Campylobacter, and Salmonella to persist and potentially regrow in the presence of the algae. As a result of wind and wave action, these microorganisms can detach and be released to surrounding waters and can influence water quality. Enteric bacterial pathogens have been detected in Cladophora mats; E. coli and enterococci may populate to become part of the naturalized microbiota in Cladophora; the high densities of these bacteria may affect water quality, resulting in unnecessary beach closures. The continued use of traditional fecal indicators at beaches with Cladophora presence is inadequate at accurately predicting the presence of fecal contamination. This paper offers a substantial review of available literature to improve the knowledge of Cladophora impacts on water quality, recreational water monitoring, fecal indicator bacteria and microorganisms, and public health and policy.

Fecal indicator concentrations of surface runoff in rural watersheds, Korea

To evaluate fecal contamination discharged from diffuse sources, flow rates and fecal indicator microorganism concentrations of rainfall runoff draining three rural watersheds were monitored. Land uses of the study watersheds were mainly unpolluted forestry and crop field with area of 14-70 ha. Monitored fecal indicators were total coliform (TC), fecal coliform (FC), Escherichia coli (EC), and fecal streptococcus (FS). Membrane filtration technique was adopted to measure all fecal indicators. Event mean concentrations of each fecal indicators were; TC was 2.32 x 10 2 to 3.68 × 10 5 CFU/100 ml; FC was 2.29 × 10 2 to 1.66 × 10 5 CFU/100 ml; EC was 1.76 x 10 2 to 1.21 × 10 2 CFU/100 ml; and FS was 1.42 x 10 2 to 8.48 × 10 4 CFU/100ml.

아산시 지표미생물의 분포와 Escherichia coli의 항생제 내성에 관한 연구

Efforts to evaluate water pollution using indicator microorganisms have been underway for decades, and driven by research on water purity control applications, water quality criteria are growing more and more strict. Furthermore, recent reports indicate that high concentrations of antibiotics are not absorbed, and are present in excrement from animals and humans dosed with unnecessarily high levels of antibiotics. This has emerged as very important issue from the standpoint of being an ecological and health hazard. In this study, water pollution was analyzed through physicochemical and microbiological means, and antibiotic resistance in indicator microorganisms was assessed. In physicochemical analysis, biochemical oxygen demand (BOD)<TEX>$_5$</TEX> and chemical oxygen demand (COD)<TEX>$_{Mn}$</TEX> evaluation showed that pollution by organisms was highest at the G1 location with a high human population, and the DP location which has many livestock-containing households. The indicator organism levels at the G1 location were: Total Coliforms (1205 colony forming units (CFU)/100 ml), Fecal Coliforms (270 CFU/100 ml), Escherichia coli (253 CFU/100 ml) and Fecal Streptococci (210 CFU/100 ml), while for the DP location levels were: Total Coliforms (1480 CFU/100 ml), Fecal Coliforms (438 CFU/100 ml), E. coli (560 CFU/100 ml), and Fecal Streptococci (348 CFU/100 ml). Levels of fecal indicator microorganisms such as Fecal Coliforms, E. coli and Fecal Streptococci were high at all locations in the fall (the period after the rainy season), and the yearly distribution was similar between these organisms. If the number of livestock-containing households was high, almost all strains of E. coli (as distinct from the other indicator organisms) showed resistance to antibiotics, with the degree of resistance varying between areas. E. coli strains from the OY area in particular, which has a high population density, showed strong resistance to AM10 and Va30. While strong antibiotic resistance was observed overall at the DP and OY locations, no resistance was observed at the EB location.

Implications of faecal indicator bacteria for the microbiological assessment of roof-harvested rainwater quality in southeast Queensland, Australia

The study aimed to evaluate the suitability of Escherichia coli, enterococci, and Clostridium perfringens for assessing the microbiological quality of roof-harvested rainwater and assessing whether the concentrations of these faecal indicators can be used to predict the presence or absence of specific zoonotic bacterial or protozoan pathogens. From a total of 100 samples tested, 58%, 83%, and 46% of samples were found to be positive for, respectively, E. coli, enterococci, and Clostridium perfringens spores, as determined by traditional culture-based methods. Additionally, in the samples tested, 7%, 19%, 1%, 8%, 17%, and 15% were PCR positive for Aeromonas hydrophila lip, Campylobacter coli ceuE, Campylobacter jejuni mapA, Legionella pneumophila mip, Salmonella invA, and Giardia lamblia beta-giardin genes, respectively. However, none of the samples was positive for E. coli O157 lipopolysaccharide, verocytotoxin 1, and verocytotoxin 2 and Cryptosporidium parvum oocyst wall protein genes. The presence or absence of these potential pathogens did not correlate with any of the faecal indicator bacterial concentrations as determined by a binary logistic regression model. The roof-harvested rainwater samples tested in this study appeared to be of poor microbiological quality, and no significant correlation was found between the concentration of faecal indicators and pathogenic microorganisms. The use of faecal indicator bacteria raises questions regarding their reliability in assessing the microbiological quality of water and particularly their poor correlation with pathogenic microorganisms. The presence of one or more zoonotic pathogens suggests that the microbiological analysis of water should be performed and that appropriate treatment measures should be undertaken, especially in tanks where the water is used for drinking.

Mapping of critical source areas for diffuse fecal bacterial pollution in extensively grazed watersheds

Microbial contamination of surface waters frequently occurs on permanent natural grasslands subject to extensive grazing. Management of these problems requires developing methods to identify critical source areas that are responsible of significant losses of fecal microorganisms. In this study, GIS analysis of watersheds was used to calculate the flow of fecal bacteria ( Escherichia coli) to the outflow of a watershed by summing bacterial flows in runoff from pixels containing cowpats. Calculations were performed in two steps: (i) identification of pixels with bacteria and runoff by modeling the distribution of cowpats and variable sources of surface runoff, and (ii) parameterization by inverse analysis of deterministic and stochastic functions for bacterial emission from cowpats and for retention during their transmission to the watershed outflow. During bacterial transport in water flow, bacterial retention on the soil surface has a large influence. Despite this effect, bacterial concentration in runoff remains high. In general, cowpat age, runoff volumes and the location and proportions of bacteria-emitting and non-emitting surfaces determine critical source areas and bacterial flows at the watershed outflow. These data are discussed in terms of feasibility of solutions for management of watercourses and grazing practices.

Microbiological attributes and biogenic amine content of probiotic Turkish fermented sausage

Microbiological attributes and biogenic amine content of Turkish fermented sausage manufactured by using probiotic starter cultures (Lactobacillus casei, L. acidophilus or their combination) were investigated before and after fermentation-drying period and during refrigerated storage at 4 ± 1 °C for 8 months at 2 month intervals. As results of the study, during fermentation and storage biogenic amine content (histamine, putrescine, cadaverine and tyramine) of the samples were increased significantly. Salmonella, Staphylococcus aureus, coliform and fecal coliform microorganisms were not detected during fermentation and storage. Probiotic microorganism counts of all samples were higher than the lower limit of 6.0 log cfu/g which is requested for probiotic foods.

Distribution of microbiological indicators of fecal pollution in the riverine substrates

Distribution of fecal microorganisms in water, periphyton, and sediment was studied along the Žrnovnica river (Croatia) over a 1.5-year period. It was found that periphyton was inhabited by the highest number of investigated bacteria, while lower numbers of them were found in sediment and the lowest in surface water of the river. The concentrations of fecal microorganisms in periphyton and partly in sediment were found to be significantly higher in the middle of the river course, near the town of Žrnovnica, while according to the analysis of surface water the highest degree of pollution was reached on its estuary. The results were explained with respect to bacterial-algal associations. Considering the fact that most of the river microorganisms are associated with periphyton and sediment particles and only a small number of them is in the free-living form, microbiological analysis of both periphyton and sediment together with water samples has been suggested when fecal pollution of a river is concerned.

Procyanidin B2 catabolism by human fecal microflora: Partial characterization of ‘dimeric’ intermediates

The catabolism by human fecal microflora of pure procyanidin B2 ((–)-epicatechin-4β → 8-(–)-epicatechin) has been investigated using a static in vitro culture model. For the first time, 24 catabolites were detected by LC–MS ( n ) with M r greater than 290 indicating that they could not have formed from just one of the epicatechin units in the procyanidin structure. Structures have been assigned on the basis of the fragmentation in the ion trap mass spectrometer and with regard to catabolic pathways known to occur in fecal microorganisms. Twenty of these ‘dimeric’ catabolites produced fragment ions characteristic of flavanols and/or proanthocyanidins. One catabolite was identified tentatively as either 6- or 8-hydroxy-procyanidin B2. Thirteen were characterized as having been microbially reduced in at least one of the epicatechin units. Five contained an apparently unmodified epicatechin unit but in at least one case this was shown to consist of the B-ring of the “upper” epicatechin unit and the A-ring of the “lower”. These ‘dimeric’ catabolites were detected up to 9 h after the start of the incubation and collectively accounted for ∼20% of the substrate.

Alternative methods in tracking sources of microbial contamination in waters

A key factor in the management and remediation of impaired ground- and surface water is the ability to distinguish the sources of faecal contamination. Several approaches have been adopted as microbial source tracking methods (MST), which are generally classified as culturing, phenotypic, genetic, and chemical MST. None of the techniques used thus far can be considered a standard; important factors, such as the statistical correlation between the source and the faecal indicator and the understanding of the environmental fate of the faecal pollutants, still need attention. The most promising MST methods available today are based on the genetic fingerprinting of faecal micro-organisms. However, research is very active also in the investigation of pharmaceuticals and personal care products discharged in the environment together with faecal waste.An updated overview of MST methods to distinguish human from animal sources of faecal pollution is presented here, focusing particularly on the potentialities of new chemical tracers.

Disinfection of spring water and secondary treated municipal wastewater by TiO2 photocatalysis

The photocatalytic disinfection of spring water and secondary treated municipal wastewater by means of UV-A irradiation over TiO2 suspensions was investigated. Water samples were taken from a spring supplying water to the city of Chania, Western Crete, Greece, while wastewater samples were collected from the outlet of the secondary treatment of Chania municipal wastewater treatment plant. The effect of various operating parameters such as photocatalyst type (rutile, anatase, mixture of anatase and rutile) and concentration (0.5–1g/L), contact time (up to 60min) and sample pH (6–8) on the disinfection as assessed in terms of faecal indicator microorganisms (total coliforms and enterococci) inactivation was examined. A commercially available Degussa P25 TiO2 powder, consisting of 75% anatase and 25% rutile, was found substantially more active than pure anatase or rutile for both groups of bacteria inactivation which increased with increasing contact time and catalyst concentration, whereas small pH changes had little effect on destruction. For both groups of bacteria tested, inactivation followed a first order kinetic expression with the gram positive Enterococcus sp. being considerably more resistant to photocatalytic disinfection than total coliforms.

Quantitative PCR for Genetic Markers of Human Fecal Pollution

Assessment of health risk and fecal bacterial loads associated with human fecal pollution requires reliable host-specific analytical methods and a rapid quantification approach. We report the development of quantitative PCR assays for quantification of two recently described human-specific genetic markers targeting Bacteroidales-like cell surface-associated genes. Each assay exhibited a range of quantification from 10 to 1 x 10(6) copies of target DNA. For each assay, internal amplification controls were developed to detect the presence or absence of amplification inhibitors. The assays predominantly detected human fecal specimens and exhibited specificity levels greater than 97% when tested against 265 fecal DNA extracts from 22 different animal species. The abundance of each human-specific genetic marker in primary effluent wastewater samples collected from 20 geographically distinct locations was measured and compared to quantities estimated by real-time PCR assays specific for rRNA gene sequences from total Bacteroidales and enterococcal fecal microorganisms. Assay performances combined with the prevalence of DNA targets in sewage samples provide experimental evidence supporting the potential application of these quantitative methods for monitoring fecal pollution in ambient environmental waters.

Fate of Indicator Microorganisms Under Nutrient Management Plan Conditions

Nutrient management plans (NMPs) for application of wastewater from concentrated animal feeding operations are designed to meet crop water and nutrient requirements, but implicitly assume that pathogenic microorganisms in the wastewater will be retained and die-off in the root zone. A NMP was implemented on a field plot to test this assumption by monitoring the fate of several fecal indicator microorganisms (Enterococcus, fecal coliforms, somatic coliphage, and total Escherichia coli). When well-water and wastewater were applied to meet measured evapotranspiration (ET), little advective transport of the indicator microorganisms occurred below the root zone and the remaining microorganisms rapidly died-off (within 1 mo). Additional experiments were conducted in the laboratory to better quantify microorganism transport and survival in the field soil. Batch survival experiments revealed much more rapid die-off rates for the bacterial indicator microorganisms in native than in sterilized soil, suggesting that biotic factors controlled survival. Saturated column experiments with packed field soil, demonstrated much greater transport potential for somatic coliphage than bacterial indicators (Enterococcus and total E. coli) and that the retention rates for the indicator microorganisms were not log-linear with depth. A worst case transport scenario of ponded infiltration on a large undistributed soil column from the field was also initiated and indicator microorganisms were not detected in the column outflow or in the soil at a depth of 65 cm. All of these observations support the hypothesis that a NMP at this site will protect groundwater supplies from microorganism contamination, especially when applied water and wastewater meet ET.

서울특별시 종로구 대중목욕탕의 수질 중 미생물 오염도 조사 연구

The aim of this study is to investigate microbial sanitary condition of public baths in Seoul, Korea. A total of 28 water samples were collected from 14 different public baths and sudatoriums. The prevalence of fecal indicator microorganisms such as total coliform, fecal coliform, and Escherichia coli was characterized. In addition, bacteria in water was membrane filtered by 0.45um nitrocellulose membrane, and the filter was analyzed by both cultivation and PCR amplification of partial 16S rRNA gene. The levels of chlorine were measured for each of water samples. More than 40% of 14 collected water samples, the concentrations of total coliform bacteria exceeded the water quality for bath water guideline. There was no significant correlation between chlorine residue and the presence of total coliform. Various microorganisms including pathogenic microorganisms were identified from cultivation and subsequent analysis of 16s rRNA gene sequences. Our results suggest that appropriate hygiene practice and continuous monitoring is needed for reducing health risk associated with public bathhouses.

Letter to the Editor

To Dr. Donnelly, Scientific Editor, Food Microbiology and Safety Section, Consumer demand for healthy, additive-free foods has led to increased consumption of raw salad vegetables in developed countries. Availability of prepared bagged salads has increased, and so have the number of studies on the microbiological quality of minimally processed vegetables ready for consumption. The initial microbial load of vegetables, especially leafy ones, plays a crucial role in the microbiological content of pre-packed salads, yet few studies have been published to this day on microorganisms of fecal origin isolated from raw/untreated vegetables. In 1980, an article, authored by the late Professor J.A. Papadakis of the Athens School of Hygiene and myself (National Salmonella-Shigella Reference Centre of Greece), was published in ‘Hippocrates’ scientific journal of the Medical School of the Univ. of Athens Greece, discussing isolation techniques for the qualitative detection of Salmonella from fresh vegetables (Papadakis and Efstratiou 1980). In Greece the practice of consuming with every meal a side plate of salad made of uncooked fresh vegetables is a widely applied practice. Irrigation with wastewater might result in vegetable contamination with fecal microorganisms. Indeed it had been published (Papavassiliou and others 1967) that vegetables from the central market of Athens were found contaminated with coli-aerogenes bacteria (86.8%) and E. coli (22.3%). In the article by Papadakis and Efstratiou, 538 samples of 7 vegetables (lettuce, tomatoes, green peppers, parsley, spinach, celery, chicory) were examined for the presence of Salmonella spp. The vegetables were locally produced and were bought from green-grocery stores in the Athens area. 300gr of each vegetable was homogenized in 300ml buffered peptone water in a stomacher and incubated at 37 °C for 16 to 20 h. Tomatoes were ‘washed’ in buffered peptone water for 3 to 5 min. Following this pre-enrichment step, enrichment was carried out by inoculation in 3 broths: Muller-Kauffmann tetrathionate broth (1 ml of inoculum in 10 ml broth), Mannitol Selenite F broth (1 ml of inoculum in 10 ml broth), and Rappaport broth modified by Vassiliadis and others (1978) (0.1 ml of inoculum in 10 ml broth). All enrichment media were incubated for 24 h and 48 h. They were streaked out on SS (Salmonella Shigella) agar (Difco) and on brilliant green agar (Oxoid 329 with the addition of 0.25% sodium desoxycholate). The plates were incubated at 37 °C for 24 h, and 4 suspect colonies from each plate, if present, were inoculated into Kligler Iron agar slants. Tubes exhibiting the characteristics of Salmonella were further examined by standard biochemical and serological methods at the National Salmonella-Shigella Reference Centre of Greece. Salmonellae were isolated from six (1.1%) of the examined samples. Only lettuce (2.0%) and parsley (8.6%) were positive. All 3 positive lettuce samples yielded Salmonella Montevideo, although they were purchased 1 wk apart each other, but from the same retailer. The 3 positive parsley samples contained Salmonella Newport, Abony, and Orion. All 6 Salmonella strains were isolated from the modified Rappaport enrichment broth. One strain was isolated from Muller-Kauffmann tetrathionate broth; no Salmonella was isolated from Mannitol Selenite F broth. The conclusion was reached that enrichment in Rappaport medium as modified by Vassiliadis was more appropriate for the isolation of salmonellae from fresh vegetables. Superiority of Rappaport-Vassiliadis enrichment broth in detecting salmonellae in food products and polluted water led to its commercial preparation as dehydrated medium ‘Rappaport-Vassiliadis (RV) enrichment broth’ (Oxoid CM669 and other manufacturers). Should any of your readers be interested in of the original article, which is in English, I would be happy to post a copy if contacted at efstratiou@aegean.gr Sincerely,

Relationships between fecal indicators and pathogenic microorganisms in a tropical lagoon in Rio de Janeiro, Brazil

Rodrigo de Freitas Lagoon is an urban ecosystem undergoing accelerated degradation, therefore selected as a model for microbiological quality studies of tropical lagoons. The aim of this study was to evaluate the abundance and the spatial distribution of fecal pollution indicators and pathogenic microorganisms in the lagoon. The relationships between microbial groups and abiotic measurements were also determined to evaluate the influence of environmental conditions on bacterial distribution and to identify the capability of coliforms and Enterococcus to predict the occurrence of Vibrio, Staphylococcus aureus, and Salmonella. Surface water samples were collected monthly, from December 1999 to October 2000. Analyses were performed by traditional culture techniques. A uniform spatial distribution was observed for all bacterial groups. The fecal pollution indicators occurred in low abundances while potentially pathogenic microorganisms were consistently found. Therefore, our study supported the use of counts of coliforms and Enterococcus to indicate only recent fecal contamination.

Analysis of volatile arsenic compounds formed by intestinal microorganisms: rapid identification of new metabolic products by use of simultaneous EI-MS and ICP-MS detection after gas chromatographic separation

For the investigation of biotransformation processes of heteroelements in the environment, both molecular and element-sensitive detection systems are used in hyphenation to chromatographic separation. In this work, we studied the potential of our recently developed gas chromatographic system with parallel electron impact mass spectrometry and inductively coupled plasma mass spectrometry (GC/EI-MS/ICP-MS) for non-target screening and subsequent identification of volatile arsenic compounds formed by fecal microorganisms. By combining the strengths of element-sensitive detection by ICP-MS and molecular identification by EI-MS, it was possible to identify five mixed arsenic/sulfur species (Me2AsSH, dimethyl-mercapto-arsine, Me2AsSMe, dimethyl-methylthio-arsine, Me2AsSSMe, dimethyl-methyldithio-arsine, (Me2As)2S, thio-bis(dimethylarsine) and MeAs(SMe)(SEt), methyl-methylthio-ethylthio-arsine) as well as one mixed arsenic/selenium compound (Me2AsSeMe, dimethyl-methylseleno-arsine) in the headspace of fecal incubations. Identification of all compounds was verified by synthesis experiments. Three of these species, namely Me2AsSeMe, (Me2As)2S and MeAs(SMe)(SEt), have not been described in environmental or human matrices before. Finally, the advantages of elemental and molecular detection after gas chromatographic separation are discussed.