SEGH Articles

Michael Watts elected SEGH President

10 October 2017
Dr Michael Watts was recently elected SEGH President, following a handover from Dr Chaosheng Zhang. Michael has been involved in the SEGH for nearly 15 years as a member of the European board and active on the International board via his role in redesigning the website since 2010.

A model for Quality Assurance, Lab Management and Good Laboratory Practices for Africa

06 October 2017
David and Takesure describe their efforts to improve quality assurance in the environmental chemistry labs in Kenya and Zimbabwe

Book review: Health protection, Principles and practice

02 July 2017
Τhe interface between the environment and health is a fascinating research topic and has traditionally been the central focus of SEGH. In fact it is this field that brings together geoscientists and medical and public health researchers and practitioners to address health problems caused or exacerbated by environmental hazards and natural disasters.

Health in Impact Assessment: primer published

02 July 2017
The changes to the EIA directive as recast in April this year (2017) brings human health very firmly into consideration. Any project which is subject to EIA (Environmental Impact assessment) is required to evaluate the impact from the project on human and population health.

SEGH Member participated in the Antarctic Circumpolar Expedition

02 July 2017
Francois De Vleeschouwer, researcher at EcoLab, (CNRS, Toulouse France) and SEGH secretary, had the opportunity to embark onboard the RV Akademik Treshnikov to participate in the ACE Expedition

Geochemistry in Africa

26 January 2017
Read about VicFalls 2018 and fieldwork in the Copperbelt

ISEH 2016, ISEG 2016 & Geoinformatics 2016

26 January 2017
Joint International Conference on Environment, Health, GIS and Agriculture Galway, Ireland, August 14 20, 2016

Zoo Elephants Aid Wild counterparts in the Kruger National Park

04 November 2016
Eight zoo elephants from Knowsley Safari Park and Twycross Zoo have been contributing to work that is being carried out to reduce Human-Elephant Conflict surrounding the Kruger National Park.

Health Protection: Principles and practice

14 October 2016
Do you struggle with understanding how to respond to the human health implications of environmental contamination? Dr Alex Stewart, a medical board member of SEGH, is an editor and contributing author of a new text covering the public health response.

Fate of smelter dusts in soils

14 October 2016
Winner of the best poster prize at the SEGH meeting in Brussels. Alice Jarosikova, PhD student from Charles University in Prague, describes her research on fate of smelter-derived dust particles in soils.

Winner of the Malcolm Brown Outstanding Young Scientist Award

12 August 2016
Gabriel Enge won the Malcolm Brown outstanding young scientist award at the 32nd SEGH International conference in Brussels. He describes his research leading to this award.

Long distance electron transport in the seafloor

21 July 2016
At the SEGH 32nd International Conference recently in Brussels, Sebastiaan Van de Velde won the best prize for PhD student oral presentation. Here he tells us a little about his research.

Malcolm Brown: at the heart of SEGH

03 July 2016
It was with great sadness that we heard of the passing of Malcolm Brown in April after a long battle with illness. Malcolm worked at the heart of SEGH as the Secretary of the society

Award for work on tackling hidden hunger

25 March 2016
Estimates suggest that more than 2 billion people could be suffering from micronutrient deficiencies.

Urban Geochemical Mapping by the Geochemistry Expert Group of EuroGeoSurveys

25 March 2016
Given the fact that by 2050 more than 80% of the European population will be living in cities (United Nations, 2014), the quality of the urban environment is becoming an important issue in the 21st century.

Mapping Hidden Hunger in Malawi

14 February 2016
Maps for Malawi predict spatial variation in the dietary supply of seven essential elements (calcium, copper, iodine, iron, magnesium, selenium and zinc).

SEGH Representation - Scientific Events in Pakistan

10 January 2016
Dr Munir Zia gives an update on SEGH representation at two scientific events during 2015 in Pakistan

Geology for Global Development: GfGD

12 December 2015
Fighting Global Poverty: Geology and the Sustainable Development Goals

Putting the Health in SEGH

18 November 2015
Dr Alex Stewart, recently retired from Public Health England, has been an active member of the SEGH International board over many years and a major driving force in bringing the health community together with environmental scientists to promote inter-disciplinary research.

32nd International SEGH conference, Brussels 2016

17 November 2015
32nd International SEGH conference, Universite Libre de Bruxelles, Brussels, Belgium, 4th-8th July, 2016.

Remedial Solutions for polluted soils: developing research collaboration between UK and China

17 November 2015
Hunan University of Science & Technology (HNUST), Xiangtan, PR, China. The School of Civil Engineering houses a Key Library for Shale Gas extraction and has undertaken work to assess resources and their low impact extraction.

Assessment of the environmental conditions of the Calore river basin (south Italy): a stream sediment approach

23 October 2015
Daniela Zuzolo from the University of Sannio won the Hemphill prize for best student presentation at SEGH 2015 in Bratislava. She provides a follow-up on her presentation.

SEGH 2015: a PhD researchers perspective

15 October 2015
Dan Middleton, a PhD student from the University of Manchester, based at the Centre for Environmental Geochemistry at the British Geological Survey, shares his account of the conference proceedings.

Environmental Geochemistry in Greece: Opportunities and obstacles to development

28 September 2015
What are the opportunities and obstacles to development in the field of environmental geochemistry and health in Greece nowadays?

The new SEGH President: Chaosheng Zhang

24 September 2015
Dr Chaosheng Zhang formally took over the position of President of SEGH in June at SEGH 2015 in Bratislava.

SEGH 2015 Conference Report

24 September 2015
Bratislava welcomed over 100 delegates from over 25 countries to SEGH 2015.

Working together to combat environmental pollution and inform agricultural strategies

10 July 2015
Environmental scientists give an account of their experience from a Commonwealth Professional Fellowship in the UK.

SEGH Urban Soils and Metal Contamination Conference, March 2015 University of Texas-Arlington

07 July 2015
The United States Section of the Society for Environmental Geochemistry and Health (SEGH), along with the University of Texas-Arlington (UTA) sponsored a conference on Urban Soils and Metal Contamination: Issues & Remedies, March 30th to April 1, 2015 on the campus of UTA.

Is there an environmental link to esophageal cancer in Tanzania?

07 July 2015
Scientists from the Centre for Environmental Geochemistry are helping health organisations understand why esophageal cancer is localised within specific areas of the African Rift Valley. Whilst various causal factors are now under investigation, such as high-strength kill-me-quick alcohol consumption or hot tea drinking, it is difficult to fully explain the localised nature of the burden. Here Dr Michael Watts outlines why soil around Mount Kilimanjaro could unearth some answers.

SEGH 2015 Bratislava

09 December 2014
The local organising institution of the 31st International Conference of the SEGH in 2015 was established in 1940 and performs the tasks of the State Geological Survey of the Slovak Republic.

Arsenic Biogeochemistry and Health

04 November 2014
The success of the 29th SEGH conference produced a special issue of papers presenting recent advances in various aspects of environmental and health impacts of contaminants, published in Environmental Geochemistry and Health

Global dispersion of trace metals in South America

04 November 2014
Pre-Hispanic metallurgical activities released enough metals to be transported throughout the entire South American continent.

The Joy's of PhD research in two countries

06 October 2014
Edwards project aim is to improve the accuracy and spatial resolution of dietary mineral supply estimates in Malawi and to investigate the potential of agricultural solutions to mitigate dietary mineral deficiencies. He has been conducting fieldwork in Malawi during 2012-14.

Dust Deposition in snow from NorthEast Antarctica: mineralogical, morphological and chemical characterization

05 October 2014
Aubry Vanderstraeten is a PhD student and won the runner-up prize for best student poster at SEGH 2014.

SEGH 2014 Conference Report

08 September 2014
Northumbria University welcomed over 120 delegates from over 25 countries to SEGH 2014.

Arsenic hazard in rice from Kandal Province, Cambodia

08 September 2014
Peter Gilbert won the student prize at SEGH 2014 for best oral presentation.

Modeling global Iodine in Global Atmosphere and its Deposition

08 September 2014
Tomas Sherwen is an Atmospheric Chemistry PhD Student and won the SEGH 2014 student prize for best poster.

SEGH Journal Impact Factor News

03 August 2014
The Society's journal Environmental Geochemistry & Health (EGAH), received good news recently with the announcement of a significant increase in its impact factor, now reaching 2.573.

Environmental Geochemistry and Consultancy in Amazonia: from my archive

24 July 2014
The problem: mercury losses from informal gold mining and health risks to the miners (garimpeiros), gold traders and local riverine communities, by Past President Iain Thornton.

Centre for Environmental Geochemistry

15 June 2014
The Centre's research will focus on building established collaborations between the University of Nottingham and the British Geological Survey (across Departments, Schools and Faculties).

Is the Indian Sundarban and adjacent regions polluted by mercury? A case study and cross sectional view

05 June 2014
The Indian Sundarban and its adjacent regions are experiencing huge population loads in terms of domestic and industrial effluents from upstream highly urbanized Calcutta and surroundings

Urban soil of Athens, Greece: Local geology beats human pollution on trace elements

04 June 2014
Bearing in mind the historical absence of heavy industry within the Greater Athens and Piraeus area, the tested hypotheses was that local geology is important in controlling the distribution of potentially harmful trace elements in urban soil.

Brick Kilns and Fish: a Symbiotic Relationship?

08 April 2014
During the 1st two weeks in March Dr Andy Marriott and Dr Simon Chenery visited India to foster ties between India and UK environmental scientists.

Back to the Future: Brian E Davies (Past President)

08 April 2014
Should we reduce our emphasis on the toxic elements? Is it time to go back to the future?

Diffusive gradients in thin films (DGT): An emerging technique for bioavailability assessment of chemicals in the environment

08 April 2014
As a rapidly developing passive sampling method for the labile forms of chemicals in waters, sediments and soils, the diffusive gradients in thin films (DGT) technique has significant advantages over conventional methods: in situ measurement, time averaged concentrations and high spatial resolution.

SEGH 2014

06 February 2014
Dr Jane Entwistle is Head of Department of Geography at Northumbria University and is organising the 2014 SEGH conference. Here she gives some insight into the host organisation and city.

The Future is Africa

05 February 2014
In early January Dr Michael Watts visited Zimbabwe and Zambia with a colleague from the University of Nottingham. They were funded from a Royal Society-DFID grant to foster science networks in Africa and to help strengthen scientific capacity. Here Michael tells us about his trip

SEGH membership

05 February 2014
A hidden opportunity: Collaborative Development of teaching and learning in Environmental Geochemistry and Health at the Department of Geology, University of Calabar, Nigeria

An historical reconstruction of atmospheric heavy metals deposition from a peat bog record on the North Shore of the St. Lawrence Estuary, Quebec

01 October 2013
Peat bogs were used to reconstruct the history of atmospheric heavy metal deposition along the St. Lawrence Valley. Results from one of the study sites were presented at the 29th SEGH held in July 2013, Toulouse.

The new SEGH President: Andrew Hursthouse

08 September 2013
Professor Andrew Hursthouse formally took over the position of President of SEGH in August 2013 following election by the SEGH board.

Environmental Geochemistry and Health

07 September 2013
Environmental Geochemistry and Health Impact Factor is 2.076 for 2012.

Trace Metal inputs in French Pyrenees: a spatial and temporal case study in the Upper valley of the Vicdessos

02 May 2013
A human-environment observatory aims to monitor the evolution of human-environment interactions within the Upper Vicdessos valley. The aim is to collect data and integrate them to conduct a transdisciplinary research in a changing environment.

Reducing human exposure to arsenic and simultaneously increasing selenium and zinc intake, by substituting non-aromatic rice with aromatic rice in the diet

01 May 2013
A team of scientists led by Dr Parvez Haris is carrying out research to identify ways of reducing human exposure to arsenic through diet

Measuring the Bioaccessibility of Potentially Harmful Elements in Soil

01 May 2013
Mark Cave provides some background for bioaccessibility testing and insight into the contribution it has made to the risk assessment industry.

In Malawi "simple is not easy"

01 March 2013
Effectiveness of sanitation, hygiene practices, and water supply interventions serving Malawi and the surrounding countries.

Tellus Border: Initial findings of a geo-environmental survey of the border region of Ireland

01 March 2013
The Tellus Border project is an EU INTERREG IVA-funded mapping project that involved baseline geochemical and geophysical surveys in the border region of Ireland, and the integration of data from these with existing data collected in Northern Ireland.

Otoliths: The little “White” box recorders of the fish world

01 February 2013
The use of fish otolith (ear bone) microchemistry has enabled scientists understand better fish migratory patterns and stock identification

SEGH review of meetings

01 January 2013
Review of SEGH meetings and conferences reported in EGAH.

Studying the effects on soil organic matter of wildfires in central Portugal

01 January 2013
The main objective of this study is testing the efficacy of pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) as a fast analytical technique to detect wildfire-induced molecular alterations of the SOM in Mediterranean Leptosols.

Is it possible to remove polymeric nanoparticles from aqueous paints during the activated sludge treatment?

01 January 2013
It is well established that polymeric nanoparticles are biocompatible at macroscopic scale, but is their behaviour the same at nanoscale?

Spatial distribution of Pb, Cd and Cr concentrations in moss transplants from urban recreational areas in Lisbon, Portugal

03 December 2012
Metal concentrations in moss were used to assess the contribution of atmospheric pollution to the geochemistry of soil and ground-level dust, and discriminate urban pollution sources.

The relationship between heavy metals and sedimentary organic matter in the Oxford Clay (Jurassic) of the southern UK

03 December 2012
Pin Ru is studying for a PhD in sedimentary organic matter and its interaction with waste in landfill sites

Sedimentary geochemistry of platinum in intertidal salt marsh sediments of the Tagus River Estuary, Lisbon, Portugal

03 December 2012
Studies of platinum in intertidal sediments have highlighted a number of features of Pt dynamics in saltmarsh environments.

Urban sediments: Geochemistry and mineralogy towards improved risk assessments

07 November 2012
Raquel was a joint oral presentation winner at the ISEG meeting in Aveiro in July 2012. The main aim of Raquel’s present research is to characterize the presence of PHE in soils and urban sediments, exploring the spatial, geochemical and mineralogical linkages within and between these media.

Report 9th ISEG, Aveiro, Portugal

07 November 2012
SEGH members were delighted to attend and participate in the 9th International Symposium on Environmental Geochemistry organised by staff from the University of Aveiro held during 15th - 22nd of July, 2012.

Notes from Malawi

07 November 2012
Plant and crop selenium concentration shows strong geochemical control, and our data suggests widespread high prevalence of dietary Se deficiency across Malawi, primarily due to the low pH of the predominant soil types causing Se to be held in an unavailable form.

SESEH Promotes Collaborations with China in Environment and Health

01 October 2012
The 2012 Sino-European Symposium on Environment and Health (SESEH 2012) was successfully held at the National University of Ireland, Galway during August 20 - 25, 2012.

How useful are on-site measurements in environmental geochemistry?

12 August 2012
How reliable are on-site measurements? Can sound decisions be made using them, or should we stick to measurements made in the remote lab?

Emerging Contaminants in the environment – is there a risk to health?

12 August 2012
In Europe and North America, there has been a gradual decrease in common environmental contaminants (heavy metals such as lead, cadmium; persistent organic pollutants such as DDT, Dioxin, PAH’s) in the environment. Common environmental contaminants, however, remain a public health concern in developing countries and newly industrialised countries.

Depositional and ecological environments of the Bay of Bengal coast of northeast India

01 May 2012
Dr. Asok Kumar Bhattacharya summarises his work at the University of Calcutta on the Sundarban wetlands in India, including work on coastal sedimentology, impact of anthropogenic pollution and coastal zone management.

The nano way to cleaner water

04 April 2012
Nanomaterials provide potential for waste water remediation and metal removal and recycling. We envisage that this composite can cheaply and effectively be incorporated into a variety of configurations to improve water treatment.

Untreated Wastewater Irrigation to Vegetable Crops in Pakistan

03 March 2012
Wastewater has been widely used for irrigation of agricultural crops as the nutrients contained in the wastewater are considered beneficial to plant growth

Exposure to Arsenic And Other Toxic Elements Through Eating Earth

01 February 2012
The practice of deliberately eating earth, known as geophagy has been common in many cultures across the world. Unfortunately, very little scientific research is being conducted in this area and its impact on human health.

The Indian Sundarban Mangrove wetland: an ecological perspective

01 February 2012
Dr Sarkar has carried out research on the changes in the ecological and pollution status of the Indian Sundarban mangrove wetlands, as a result of intense anthropological pressures affecting the biotic and abiotic compartments of this fragile ecosystem.

Environmental Geochemistry Health: on-line access

01 January 2012
Environmental Geochemistry and Health is now available to via on-line access to members (Full and Student). Log in through www.segh.net to access the Springer back catalogue of EGH.

Waste glass as a substrate for As removal from drinking waters in Bangladesh: a laboratory and field-based study

03 December 2011
This research project examines the application of recycled glass and waste stainless steel fragments as a practical medium for As removal at a household scale.

Ozone as a remediation technique for the treatment of hydrocarbons in post industrial sites in Glasgow

01 November 2011
Andrew Robson was a runner up for the Springer / Hemphill Best student Oral presentation at SEGH 2011.

Environmental Public Health Tracking Proof of Concept Study: hazard tracking in private drinking water supplies

01 October 2011
The Health Protection Agency undertook a proof of concept study to appraise the chemical quality of private drinking water supplies in East Cornwall and map their metal and mineral content relative to geological formation.

Cadmium (Cd) contamination of paddy fields in Mao Tao, Western Thailand

01 September 2011
Peerapat Kosolsaksakul is a 2nd year PhD student who was winner of the Springer / Hemphill Best Poster presentation at SEGH 2011.

Carbon and Contaminant Trace Metal Biogeochemistry in Surficial Organic-rich Terrestrial Systems

01 September 2011
David Blair was the runnner up for the Springer / Hemphill Best Oral presentation at SEGH 2011.

Multiproxy climate reconstruction from raised bog deposits along the West Coast of the British Isles

01 August 2011
Anke Kuttner was Runner up for the Springer / Hemphill Prize for Student Poster presentation at SEGH 2011 in Ormskirk, UK.

Flux Based Management of a Groundwater Pollution: from Mass Flux Measurements to Regulatory Decisions

01 August 2011
Goedele Verrydt won the Springer / Hemphill Prize for Student Oral Presentation at SEGH 2011 in Ormskirk, UK.

"Chernobyl: now open to tourists" - Risk communication or public engagement

15 June 2011
The Ukraine government is not only to lift restrictions on access to the restricted zone around the site of the Chernobyl nuclear reactor, but also plan for redevelopment and repopulation.

Application of geochemical signatures of shale in environmental pollution and human health assessment in South East Nigeria

15 June 2011
Therese Ntonzi Nganje describes her experience through a Commonwealth Scholarship scheme on connecting Nigerian and UK scientists.

Ecosystem services to alleviate micronutrient malnutrition in Sub Saharan Africa

20 May 2011
Ecosystem Services concepts have great potential for linking biogeochemistry, health and policy formulation for poverty alleviation.

Soil: an important part of a healthy diet?

20 May 2011
Iodine is essential for healthy human life, and is taken up by crops from the soil. However, current research shows that the soil itself has an important part to play in determining how much iodine reaches our food.

Beyond mapping: new applications of GIS in environmental geochemistry and health

21 April 2011
GIS has been widely used to produce professional maps. However, the potential applications of GIS are far beyond mapping.

Journey from PhD student to employment: difficult but rewarding

21 April 2011
Dr Mark Button has a few words of comfort for students nearing the job market and searching for their future employment

Student led remediation study of Manitoban Gold mine

21 March 2011
Jill Maxwell was the joint winner of the Hemphill prize for best oral presentation at Galway SEGH 2010. She describes her work on the remediation of arsenic contamination by a natural wetland at New Britiannia Mine, Manitoba.

Nutrient export coefficients and the Northern Ireland Environment Agency river nitrate data

21 March 2011
Judith Watson was the joint winner of the Hemphill prize for best oral presentation at Galway SEGH 2010.
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Science in the News

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

  • Assessment of radon concentration and heavy metal contamination in groundwater of Udhampur district, Jammu & Kashmir, India 2017-10-16

    Abstract

    Radon concentration was measured in water samples of 41 different locations from Udhampur district of Jammu & Kashmir, India, by using RAD7 and Smart RnDuo monitor. The variation of radon concentration in water ranged from 1.44 ± 0.31 to 63.64 ± 2.88 Bq L−1, with a mean value of 28.73 Bq L−1 using RAD7 and 0.64 ± 0.28 to 52.65 ± 2.50 Bq L−1, with a mean value of 20.30 Bq L−1 using Smart RnDuo monitor, respectively. About 17.07% of the studied water samples recorded to display elevated radon concentration above the reference range suggested by United Nation Scientific Committee on the Effects of Atomic Radiations (UNSCEAR). The mean annual effective dose of these samples was determined, and 78.95% samples were found to be within the safe limits set by World Health Organisation (WHO) and European Council (EU). The study revealed good agreement between the values obtained with two methods. Heavy metals (Zn, Cd, Fe, Cu, Ni, As, Hg, Co, Pb and Cr) were determined in water samples by microwave plasma atomic emission spectrometer, and their correlation with radon content was also analysed.

  • Detecting the effects of coal mining, acid rain, and natural gas extraction in Appalachian basin streams in Pennsylvania (USA) through analysis of barium and sulfate concentrations 2017-10-13

    Abstract

    To understand how extraction of different energy sources impacts water resources requires assessment of how water chemistry has changed in comparison with the background values of pristine streams. With such understanding, we can develop better water quality standards and ecological interpretations. However, determination of pristine background chemistry is difficult in areas with heavy human impact. To learn to do this, we compiled a master dataset of sulfate and barium concentrations ([SO4], [Ba]) in Pennsylvania (PA, USA) streams from publically available sources. These elements were chosen because they can represent contamination related to oil/gas and coal, respectively. We applied changepoint analysis (i.e., likelihood ratio test) to identify pristine streams, which we defined as streams with a low variability in concentrations as measured over years. From these pristine streams, we estimated the baseline concentrations for major bedrock types in PA. Overall, we found that 48,471 data values are available for [SO4] from 1904 to 2014 and 3243 data for [Ba] from 1963 to 2014. Statewide [SO4] baseline was estimated to be 15.8 ± 9.6 mg/L, but values range from 12.4 to 26.7 mg/L for different bedrock types. The statewide [Ba] baseline is 27.7 ± 10.6 µg/L and values range from 25.8 to 38.7 µg/L. Results show that most increases in [SO4] from the baseline occurred in areas with intensive coal mining activities, confirming previous studies. Sulfate inputs from acid rain were also documented. Slight increases in [Ba] since 2007 and higher [Ba] in areas with higher densities of gas wells when compared to other areas could document impacts from shale gas development, the prevalence of basin brines, or decreases in acid rain and its coupled effects on [Ba] related to barite solubility. The largest impacts on PA stream [Ba] and [SO4] are related to releases from coal mining or burning rather than oil and gas development.

  • Toxic effects of oxytetracycline and copper, separately or combined, on soil microbial biomasses 2017-10-12

    Abstract

    The production of commercial livestock and poultry often involves using with antibiotics and feed additives, such as oxytetracycline (OTC) and copper (Cu). These are often excreted into the soil by animal feces; hence, combined pollutants may contaminate the soil. To evaluate single and combined toxic effects of OTC and Cu on the soil ecology, changes in quantities of bacteria, fungi, and actinomycetes in the soil were studied over a 28-d incubation period by a plate count method, microbes numbers counted on days 7, 14, 21, and 28. Abundances of ammonia monooxygenase (amoA) gene expression by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in soil samples also were tested by real-time polymerase chain reactions (RT-PCRs) on day 21. The results revealed that the numbers of bacteria, fungi and actinomycetes and amoA genes copies of AOA and AOB were reduced seriously by exposure to Cu (1.60 mmol/kg). Similarly, the combined pollution treatments (mole ratios of OTC: Cu was 1:2, 1:8, and 1:32) also had inhibitory effect on bacteria, fungi, and actinomycetes numbers and amoA gene copies of AOA and AOB; the inhibitory rate was on obvious growth trend with the increasing mole ratios. Effects from single OTC pollution were found on bacteria (days 7 and 14), fungi (days 7, 14, 21, and 28), and AOA-amoA gene copies (day 21), with promotion at a low concentration (0.05 mmol/kg) and suppression at higher concentrations (0.2 and 0.8 mmol/kg). Also, numbers of bacteria, fungi, and actinomycetes decreased with longer culture times. Combining OTC and Cu led to a higher inhibition of soil microbes than when either chemical was used alone. However, there was no significant relationship between single and combined toxic chemicals because of their complicated interactions, either antagonistic or synergistic. The results also indicated the sensitivity of bacteria, fungi, actinomycetes on toxic chemicals existed difference and that the AOA were more tolerant than the AOB to these chemicals.