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ACN Oct 02, V3 N01

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  • weinhc2
    ===================================================================== Arsenic Crisis News October 2002 V3 N01
    Message 1 of 1 , Sep 25, 2002
      Arsenic Crisis News
      October 2002 V3 N01

      + This Issue of ACN

      + New Arsenic-Crisis Group at Yahoogroups -
      arsenic-crisis-news, arsenic-source, arsenic-safewater,
      and arsenic-medical are being merged

      + ACIC/ACN Supporters

      + Feature Article

      + Tenders & Vacancies

      + Upcoming Meetings & Conferences
      Updated Conference Webpages & Sites

      + Selected Recent Media Articles Online

      + New & Newly Discovered Scientific/Technical Publications
      On & Off Line

      + New & Newly Discovered Web Sites & Web Pages
      Updated Websites & Web Pages

      + New & Newly Discovered Real World Stuff

      + Publication & Other Details

      ACN is published by the Arsenic Crisis Info Centre, (c) ACIC.
      Website http://www.bicn.com/acic. Editor Sara Bennett.

      Email addresses appear in this newsletter with a space before & after
      the @ symbol. To send email to an address, you must first remove the

      See end of message for how to subscribe, unsubscribe, submit, etc.


      This is the first issue of ACN in over a year. My apologies for the
      long delay, which occurred for personal reasons.

      Please send me ASAP (at acic @ bicn.com ) any announcements, new
      papers, etc., that you would like to have included in the next issue.


      arsenic-crisis-news, arsenic-source, arsenic-safewater, and
      arsenic-medical are being merged

      To ensure that in future information gets out in a more timely
      fashion, over the coming weeks I will be shifting ACN subscribers
      over to a new ACIC discussion group at yahoogroups, called
      arsenic-crisis. arsenic-crisis has already merged the ACIC
      discussion groups arsenic-source, arsenic-safewater, and
      arsenic-medical. It seemed advantageous to merge these three groups
      because subscriber numbers were relatively low; increasingly posted
      items were of interest to two or three of the groups, necessitating
      cross posting; and message traffic was light.

      Based on the history of ACN and the three old discussion groups, I
      don't think arsenic-crisis will have excessive message traffic. The
      posting and files archives of all four superceded groups will remain
      online, but new postings to them will not be accepted.

      Over the coming weeks as the changover is implemented, each of you
      will receive an email from yahoogroups notifying you that your
      arsenic-crisis-news subscription has been switched over to
      arsenic-crisis. Unless you want to leave the (new) group, you need
      not reply to this email.

      To post directly to the new group, email your information (plain text
      only, no attachments) to:

      arsenic-crisis @ yahoogroups.com

      Posting directly to arsenic-crisis is by far the best procedure, for
      several reasons. (1) Your message will be shown as having come from
      you rather than from me, (2) messages sent to the discussion groups
      are quicker for me to moderate, which means they get posted more
      quickly, and (3) I don't have to check with you whether you do in
      fact want the information posted to the group (not clear for many of
      the arsenic-related emails I receive).

      However, any messages that reach me via sbennett @ bicn.com, acic @
      bicn.com etc will be moderated and posted to arsenic-crisis, when
      this is appropriate and with the sender's consent.


      Thanks to those who supported ACIC/ACN financially in 2000-1:

      Resource Planning & Management Consultants (RPMC), Dhaka

      London Arsenic Group (2000-2)

      Gregory P. Miller, Daniel B. Stephens & Associates

      Arup K. SenGupta, Lehigh University

      Dr. Suzanne Hanchett, Planning Alternatives for Change

      Ferdous Mahmood, Malcolm Pirnie

      Don Schroeder, SIM Bangladesh

      Their contributions partially covered the cash costs of the ACIC
      website and ACN newsletter (ie cost of website hosting, ISP
      connection, HTML software, share of computer equipment costs).

      I would also like to thank every one of you who has been supporting
      ACIC in other ways over the last year, through general encouragement
      and cheerleading (much appreciated) and by sending me information
      about your own work as well as others' news articles and papers. In
      particular I want to thank Dirk Frans, who has brought many refereed
      articles to my attention, that he locates using a keyword watch
      system that he has set up on this topic.

      A no-cost-to-you way to support the newsletter & website financially
      is to bookmark the following three links and use them when you buy
      from these merchants -

      When you buy from amazon.com, enter their site by using this link:


      When you buy from Barnes & Noble online, enter their site by using
      this link:


      Sign up with for webhosting with wso.net (hosting I use - great
      service at a great price) using this link:


      Or, if you would like to donate to ACIC/ACN for 2002-3 and (for USD25
      or more) get your name on the website home page as a supporter,
      please email me at acic @ bicn.com to arrange payment – several
      modes of payment are possible.

      Donations above and beyond ACIC/ACN's current cash costs will be
      donated to a worthy community-level arsenic pilot project or study.

      Thanks again for your support.


      From the just pretty cool dep't:

      Dr. David J Wilson has been working with high school students in
      Tennesee on the arsenic problem. Here is an abstract for one of the
      papers prepared by the students. I don't know what *you* were doing
      in high school ... I certainly wasn't doing anything nearly this
      nifty. Any comments to acic@... and I will forward them to Dr.

      A Monte Carlo risk assessment of arsenic contamination of drinking
      water in Bangladesh - Eric Chang, Martin Luther King Magnet High
      School, Nashville, TN, USA

      Abstract - Risk quotient distributions were generated based on
      arsenic concentration, daily water intake, and body mass statistical
      distributions appropriate for Bangladesh. An EPA risk assessment
      methodology was used. Monte Carlo techniques generated normally
      distributed body weights, lognormal arsenic concentrations in
      groundwater, and lognormally distributed daily intake volumes. Data
      were taken from EPA reports and from internet sites describing the
      arsenic situation in Bangladesh. Although regulatory agencies accept
      risk quotients of 1 or less as safe, only about 7% of the simulated
      Bangladesh population had risk quotients of 10 or less and fewer than
      0.01% had risk quotients of 1 or less. The risk assessment
      compellingly confirms the tragic severity of the situation in
      Bangladesh. Calculations were also done that indicate that the U.S.
      drinking water standard at that time, 0.05 mg/L, was not protective
      of public health according to EPA's risk assessment methodology.

      Methodology - The main objective of the project was to generate and
      analyze a set of risk quotients representative of the distribution of
      risk from arsenic in drinking water in Bangladesh. The risk quotient
      (RQ) is a dimensionless number that gives a measure of the risk to
      health associated with a contaminant. For lifetime exposure to a
      toxic contaminant in drinking water the risk quotient is given by

      (vw) X (c)
      RQ = -----------
      (bw) X (rf)

      where vw is the individual daily water intake (L/day), c is the
      concentration of the toxic substance (mg/L), bw is the body weight of
      an individual (kg), and rf is the risk factor of the toxic substance
      (mg/kg day). Risk quotients greater than unity are regarded as
      indicating a significant health hazard. The risk factor for
      lifetime oral exposure to arsenic used by the U.S. EPA is 0.0003
      mg/kg day

      If one is dealing with a population, one must consider the
      distributions of daily water intake, arsenic concentrations, and body
      weights. Body weights were assumed to be normally distributed with
      truncation; minimum body weight 15.12, maximum body weight 103.5,
      mean 63.9 kg, standard deviation 15.9 kg. Daily water intakes were
      assumed to be lognormally distributed with a minimum of 0.5, a
      maximum of 4.0, a geometric mean of 3 L/day, and a standard deviation
      of the log (base e) of0.276. Bangladesh well water arsenic
      concentrations were assumed to be lognormally distributed and were
      taken from internet reports and articles from that country. The
      minimum value reported was 0.0005, and the maximum was 9 mg/L. The
      geometric mean was taken to be the mean of all reported geometric
      means; its value was 0.262 mg/L. The standard deviation of the log
      was 0.884.

      A computer program was written to generate 32,000 sets of parameters
      from which 32,000 values of the risk quotient (RQ) were calculated
      and sorted (Shell-Metzner sort). Percentile values of the RQ were
      then determined from the sorted list. Results were as follows:

      * 0.01% or less of the population had values of 1 or less.

      * RQs ranged as high as 2000; symptoms of arsenic poisoning
      appear at RQs of around 40.

      * The 5th percentile value of the RQ was 8.3, the median was 39, and
      the 95th percentile value was 187. (Recall that RQ values of 1 or
      less are regarded as safe.)

      These figures certainly confirm the severity of the tragic situation
      in Bangladesh.

      Another set of calculations was done using the assumption that all of
      the groundwater is treated to bring arsenic concentrations to a
      constant value of 0.05 mg/L. This calculation yielded the following

      * The highest RQ value was about 40 (rather than 2000, as above).

      * The 5th percentile value of the RQ was 4.3, the median was 7.5, and
      the 95th percentile value was 13.6.

      * Unfortunately, none of the RQ values were 1 or less.

      One notes that, while an arsenic concentration of 0.05 mg/L results
      in substantial improvement over the present situation in Bangladesh,
      it does not appear to provide the level of protection of public
      health that is regarded as acceptable in the U.S. Further
      calculations demonstrated that an arsenic concentration of 0.0037
      mg/L yields a 95th percentile value of the RQ of 1.

      Similar calculations for a U.S. population (of somewhat greater body
      weight) indicates that an arsenic concentration of 0.0043 mg/L yields
      a 95th percentile value of 1 for the RQ. This suggests that the
      present U.S. drinking water standard for arsenic, 0.01 mg/L, is
      substantially more protective of public health than the previous
      standard, 0.05 mg/L.


      Office of Ground Water and Drinking Water, U.S. EPA (1998). Arsenic
      in Drinking Water: Drinking Water Standards Development [online].

      Voluntary Action Program, Division of Emergency and Remedial
      Response, Ohio Environmental Protection Agency (1996). Support
      Document for the Development of Generic Numerical Standards and Risk
      Assessment Procedures

      World Health Organization (1997). Arsenic in Drinking Water and
      Resulting Arsenic Toxicity in India and Bangladesh. New Delhi,
      India: Regional Office for Southeast Asia.


      The author is indebted to Dr. David J. Wilson, Mrs. Caye Boone, and
      his parents for help and advice in the development of this project.

      [None this issue]



      Arsenic Exposure and Health Effects IV - Proceedings of the Fourth
      International Conference on Arsenic Exposure and Health Effects,
      18-22 June, 2000, San Diego, CA, USA

      Publisher's page for this book, provides a description, the table of
      contents, and bibliographic & ordering information.


      Final report and proceedings for the BUET-UNU International Workshop
      Technologies For Arsenic Removal From Drinking Water, 5-7 May Dhaka,


      15-19 June 2003 - Special Symposuim on Arsenic in Soil and
      Groundwater Environments: Biogeochemical Interactions, 7th
      International Conference on Biogeochemistry of Trace Elements

      Organized by Richard H. Loeppert (USA), Soil and Crop Sciences Dept.,
      Texas A&M University, email r-loeppert @ tamu.edu; Prosun
      Bhattacharya (Sweden) Dept of Land and Water Resources Engineering,
      Royal Institute of Technology, SE-10044 STOCKHOLM, Sweden, email:
      prosun @ kth.se ; and Alan H Welch (USA) United States Geological
      Survey, Carson City, Nevada, USA email ahwelch @ usgs.gov.


      Articles are sorted by publication date, most recent first. The
      comprehensive list of arsenic-related News From Bangladesh articles
      will be posted later - I hope.

      http://www.independent.co.uk/ story.jsp?story=323650

      Bangladeshis take British scientists to court over arsenic in
      drinking water

      By Robert Verkaik Legal Affairs Correspondent
      The Independent [UK; August 12, 2002]

      A group of Bangladeshis has begun legal proceedings at the High Court
      in London against British scientists over allegations that they
      failed to prevent arsenic poisoning of thousands of people.

      In a writ lodged this week, the Bangladeshi villagers claim that the
      British Geological Survey (BGS) was negligent in work it did in
      central and eastern Bangladesh in 1992 to assess toxicity after aid
      programmes paid for sinking new wells.... [continued at
      http://www.independent.co.uk/ story.jsp?story=323650 ]


      Water filter set to save lives, by Alistair Lawson, BBC correspondent
      in Dhaka - 14 Jul 2002

      A Bangladeshi professor is due to formally launch a new water filter
      on Sunday, which its backers say will save millions of lives around
      the world. The filter, which contains a mixture of crushed bricks
      and ferrous sulphate heated together, will be showcased at the world
      conference on arsenic poisoning in the United States. It is
      specifically designed to extract arsenic and lead from millions of
      tube wells all over the country. Supporters of the filter say it
      could prove to be a major breakthrough in the battle against arsenic

      "About a year and a half ago, a professor came into my office and
      asked if I could help him, and I said 'certainly, I'll try'," said
      academic David Nunley. Professor Fakhrul Islam then told David
      Nunley, of the non-governmental organisation International
      Development Enterprises, about the water filter and asked for his
      help in its promotion....

      The filter has been invented by a Bangladeshi scientist for
      Bangladeshis, only costs around $3, and can supply enough drinking
      water every day for a family of four. So highly acclaimed is the
      invention that the United Nations is helping to organise a campaign
      that will distribute the filter to every village in the country....

      Already, the filter has been introduced on a trial basis to villages
      across the country. For women like Koli, the affect has been
      remarkable. "The people in our village know this filter can save
      their lives. Many people who had the first signs of arsenic poisoning
      have now been cured," she said.

      Backers of Professor Islam's filter hope that the publicity that it
      receives at the Arsenic conference in San Diego will help raise funds
      to end arsenic contamination in Bangladesh, described by the World
      Health Organization as the largest mass poisoning in human history.


      Bangladeshis Sipping Arsenic as Plan for Safe Water Stalls. By Barry
      Bearak, The New York Times 14 Jul 2002. Excellent overview article
      on the current situation in Bangladesh.

      Arsenic contamination affects millions in Bangladesh. News article,
      Lancet 359, 30 Mar 2002.


      Arsenic poses stroke risk, BBC News Online, 26 Mar 2002

      Arsenic poisoning through contaminated drinking water can lead to
      diseased arteries, which in turn can cause heart attacks and strokes,
      research shows. Scientists say they have identified a link between
      long-term exposure to arsenic and the accelerated development of
      atherosclerosis or progressive narrowing and hardening of the
      arteries leading to the brain. The findings, published in the
      Journal of the American Heart Association [see Circulation article
      referenced below - ed.], strongly point to arsenic and possibly other
      pollutants, as risk factors for blood vessel disease throughout the


      Arsenic affecting Bangladesh crops - food self-sufficiency might no
      longer be enough, by the BBC's science correspondent, Richard Black.
      16 Jan 2002

      Crops in Bangladesh are being contaminated with arsenic from water
      used for irrigation, according to research by Bangladeshi and
      Australian scientists. They found evidence of high concentrations of
      the poisonous substance in rice and vegetable plants....


      In no particular order this issue!


      Arsenic Report, School of Environmental Studies [Jadavpur University,
      Calcutta], July 2002

      [download Fact Sheet No. 17 as an MS-Word file]

      les/FactSheetsDisasterForum/ [list of all Disaster Forum Fact Sheets]

      Disaster Forum Fact Sheet No. 17, Dec 2001

      cgi%2Fsearch&journalcode=circulationaha [Abstract is free, full
      text/pdf requires payment for article or journal subscription]

      Biological gradient between long-term arsenic exposure and carotid
      atherosclerosis. Chih-Hao Wang, Jiann-Shing Jeng, Ping-Keung Yip,
      Chi-Ling Chen, Lin-I Hsu, Yu-Mei Hsueh, Hung-Yi Chiou, Meei-Mann Wu,
      and Chien-Jen Chen. Circulation 2002;105:1804.

      Abstract: Background - Long-term exposure to ingested arsenic has
      been documented to induce peripheral vascular disease, ischemic heart
      disease, and cerebral infarction in a dose-response relationship.
      This study further examined the biological gradient between ingested
      inorganic arsenic and carotid atherosclerosis. Methods and Results -
      We studied 199 male and 264 female adult residents from the
      southwestern area of endemic arseniasis in Taiwan. The extent of
      carotid atherosclerosis was assessed by duplex ultrasonography.
      Diabetes mellitus was determined by oral glucose tolerance test,
      hypertension by mercury sphygmomanometers, and serum lipid profiles
      by autoanalyzers. Information regarding the consumption of
      high-arsenic artesian well water, cigarette smoking, and alcohol
      consumption was obtained through standardized questionnaire
      interviews. Logistic regression analysis was used to estimate the
      odds ratio and its 95% CI of carotid atherosclerosis for various risk
      factors. Three indices of long-term exposure to ingested arsenic,
      including the duration of consuming artesian well water, the average
      arsenic concentration in consumed artesian well water, and cumulative
      arsenic exposure, were all significantly associated with prevalence
      of carotid atherosclerosis in a dose-response relationship. The
      biological gradient remained significant after adjustment for age,
      sex, hypertension, diabetes mellitus, cigarette smoking, alcohol
      consumption, waist-to-hip ratio, and serum levels of total
      cholesterol and LDL cholesterol. The multivariate-adjusted odds
      ratio was 3.1 (95% CI 1.3 to 7.4) for those who had a cumulative
      arsenic exposure of 20 mg/L-years compared with those without
      exposure to arsenic from drinking artesian well water. Conclusions -
      Carotid atherosclerosis is associated with ingested inorganic
      arsenic, showing a significant biological gradient.


      Arsenite is a cocarcinogen with solar ultraviolet radiation for mouse
      skin: An animal model for arsenic carcinogenesis. Rossman, T.G.,
      Uddin, A.N., Burns, F.J. and Bosland, M.C. 2001. Toxicol. Appl.
      Pharm 176:64-71.

      Abstract: Although epidemiological evidence shows an association
      between arsenic in drinking water and increased risk of skin, lung,
      and bladder cancers, arsenic compounds are not animal carcinogens.
      The lack of animal models has hindered mechanistic studies of arsenic
      carcinogenesis. Previously, this laboratory found that low
      concentrations of arsenite (the likely environmental carcinogen)
      which are not mutagenic can enhance the mutagenicity of other agents,
      including ultraviolet radiation (UVR). This enhancing effect appears
      to result from inhibition of DNA repair by arsenite. Recently we
      found that low concentrations of arsenate disrupted p53 function and
      upregulated cyclin D1. These results suggest that the failure to
      find an animal model for arsenic carcinogenesis is because arsenite
      is not a carcinogen per se, but rather acts as an enhancing agent
      (cocarcinogen) with a genotoxic partner. We tested this hypothesis
      with solar UVR as carcinogenic stimulus in hairless Skh1 mice. Mice
      given 10 mg/l sodium arsenate in drinking water for 26 weeks had a
      2.4-fold increase in yield of tumors after 1.7 KJ/m2 UVR three times
      weekly compared with mice given UVR alone. No tumors appeared in mice
      given arsenate alone. The tumors were mostly squamous cell
      carcinomas, and those occurring in mice given UVR plus arsenite
      appeared earlier and were much larger and more invasive than in mice
      given UVR alone. These results are consistent with the hypothesis
      that arsenic acts as a cocarcinogen with a second (genotoxic) agent
      by inhibiting DNA repair and/or enhancing positive growth signaling.


      The arsenic problem and its awareness in Bangladesh population:
      results of a large population-based survey. M.F. Parvez, H. Ahsan,
      Y. Chen, A. van Geen, A.Z.M.I. Hussain, H. Momotaj, A. Horneman, R.
      Dhar, Y. Zheng, M. Stute, H.J. Simpson, V. Slavkovich, N.J. Lolacono,
      M. Shahnewaz, K.M. Ahmed, and J.H. Graziano. Paper presented at
      "Arsenic in Drinking Water" international conference at Columbia
      University 26-27 Nov 2001.

      Abstract: The study aimed to investigate the distribution and
      magnitude of arsenic exposure in Bangladesh population and to
      understand their awareness of the arsenic problems and possible
      remediation options. Through house-to-house survey, we sampled 5,000
      contiguous tube-wells, interviewed the well-owners/caretakers and
      enumerated and gathered data on all well-users in three unions of
      Araihazar, Bangladesh. More than half of the 55,000 residents in
      these three unions were found to be drinking well-water with arsenic
      concentration more than 50 ug/L. Majority (57%) of the people
      interviewed were aware of the health risks of arsenic and 88% of them
      associated it with skin related symptoms. Higher socioeconomic
      status was associated with higher awareness of health consequences of
      arsenic exposure. Almost every respondent (98%) was willing to take
      steps to overcome this problem. A solution based on existing
      tube-wells was favored by the most (77%), which seemed to be related
      to respondent's awareness of health risks. Arsenic in drinking water
      poses as a massive public health problem in Bangladesh and increasing
      awareness about the health consequences of arsenic in the population
      may be an important step in tackling the problem.


      Effect of Spirulina on Arsenicosis Patients in Bangladesh. Hassina
      Momotaj and A Z M Iftikhar Hussain. Paper presented at "Arsenic in
      Drinking Water" international conference at Columbia University 26-27
      Nov 2001.

      Abstract: A double-blind randomized clinical trial was carried out
      among Arsenicosis patients of Sonargaon thana of Narayanganj
      district, to see the effect of Spirulina on Arsenicosis disease
      resulting from drinking arsenic contaminated ground water through
      hand pump tubewells in many parts of Bangladesh. Spirulina is a
      microscopic blue green algae, used as a food supplement but it has
      some therapeutic value in treating some ailments. It is rich in
      protein, amino acid, beta-carotene, vitamins etc. 50 arsenicosis
      patients has been identified through simple random sampling from 185
      arsenicosis patients of three villages, who had been diagnosed as
      cases of arsenicosis by the physicians, depending on the presence of
      visible signs. The patients included male and female of different
      age. A double blind method was followed during the drug
      distribution. It was found after distribution that 33 patient got
      Spirulina and 17 patient got placebo. 3 gm Spirulina per day per
      person and same dose of placebo was used as drugs for three-month
      duration and consumption of arsenic free safe water was ensured for
      both the group (Spirulina and placebo) during the total duration of
      study. Physical examinations of these patients were done carefully
      at every fifteen days interval during the intervention using a
      structured checklist. After three month it was found that 27
      (81.81%) patients showed evidence of improvement by diminishing the
      visible manifestation among 33 patients who got Spirulina. [Two
      patients showed the signs of improvement among the fifteen patients
      who received placebo.]


      The World Bank Arsenic Mitigation Program in Bangladesh. Carter
      Brandon, Lead Environmental Economist, World Bank. Paper presented
      at "Arsenic in Drinking Water" international conference at Columbia
      University 26-27 Nov 2001.

      Abstract: The World Bank is sponsoring two projects in Bangladesh
      through IDA credits. The first, begun in 1999, is the Bangladesh
      Arsenic Mitigation Water Supply Project (BAMWSP). This $44 million,
      4-year project includes identification of affected wells, provision
      of alternative sources of arsenic-safe water, and capacity-building
      at the national and local levels. All known affected upazilas should
      be covered by completion of BAMWSP in mid-2002. BAMWSP has also
      provided some resources for research, awareness-raising and training,
      most notably research into field methods for well testing, arsenic
      removal schemes, and hydrogeology of the deep aquifer.

      A second project of similar size on public health has been proposed
      and will likely commence in mid-2002. This project will have four
      components: behavior change communication to educate the public
      about arsenic, its health effects, exposure avoidance, and treatment
      options; training of health care providers to enhance capacity for
      the diagnosis, treatment, and counseling of patients; research on
      prevalence, incidence, and treatment to enable sound public health
      planning and intervention; and case management of individuals already
      affected by arsenic.


      New improved earthenware water purifiers, a sneak preview of candle
      production. Reid Harvey, Ceramic Industrial Design Consultant.
      Webposted 8 Mar 2002.

      "Earthenware water purification candles are set to be introduced
      within the coming weeks to Bangladesh based organizations that are
      dedicated to safe water options for the poor....these [filter candles
      achieve] 100% removal of the fecal coliforms that cause gastro
      intestinal diseases.... The candle price will be kept low [USD0.25
      each] by getting village potters producing them around the country.
      Thus the poor will be purchasing water purifiers made near their own
      community, by small entrepreneurs of similar means. Because of
      appropriate technology with respect to use of the candle and its
      manufacture, this offers an attractive alternative to the arsenic
      tainted water from tube wells. This alternative makes possible the
      collection of surface water."

      [Related article, on an assessment of this filter technology in

      Ceramic filters - effective household option for bacteria-free water
      Source Water And Sanitation Weekly, Issue No. 7-8, 26 February 2002

      USAID-funded research has shown that the Potters for Peace (PFP)
      (Nicaragua) colloidal silver impregnated ceramic filter effectively
      reduces bacterial indicators by 98-100% in the laboratory. Filters as
      old as 7 years were tested and found to still remove 100% of total
      and faecal coliform. Although results for other contaminants were
      inconclusive, the ceramic filter seemed to be less effective in
      removing viruses, arsenic, pesticides and volatile organic
      contaminants (VOCs). The research, conducted by Daniele Lantagne, MIT
      Lecturer in Civil and Environmental Engineering and Principal of
      Alethia Environmental in Oct-Dec 2001, concludes that, "with an
      education component for the users, the PFP filter is an effective and
      appropriate technology that improves both water quality and human

      [virus-checked self-extracting zipped MS-Word file]

      An overview of arsenic contamination in groundwater of Nepal and its
      removal technologies at household level. Amar Neku and Nirmal
      Tandukar. Paper presented on Environment Day (5 Jun) 2002.

      Abstract: A recent test result of about 17066 Terai tube wells of
      Nepal on Arsenic, as published by the National Steering Committee on
      Arsenic, show that nearly 31 % of the tested tube wells have exceeded
      the WHO standard of 10 mgL-1 and 4 % have exceeded the Bangladesh,
      China, India, and Interim Nepal Standard of 50 mgL-1. On the basis of
      the study hitherto conducted, the four most greatly affected
      districts are found to be Nawalparasi, Rautahat, Parsa, and Bara....
      [T]he authors would like to present in this paper only a couple of
      options that have been tested in Nawalparasi district for the removal
      of arsenic at household levels. One of the best treatment options at
      household levels is a 3-Gagri filter to remove arsenic and iron since
      no foreign materials and chemicals are required in this method. In
      addition, it utilizes local materials such as fine and coarse sand,
      wood charcoal, nails, brickbats, and unglazed burnt clayed pots. The
      arsenic removal efficiency of 3-gagri filters installed at Tilakpur
      and Thulokunuwar villages of Nawalparasi district have been observed
      initially as 84.5 % and 76.5 % (Day 0) and reached maximum upto 94.8
      % (Day 2) and 85.2 % (Day 14), respectively. The iron and turbidity
      removal efficiency of these filters are very promising as in both
      cases the initial iron content of 1.9 mg L-1 reduced to zero.
      Likewise, initial turbidity of 25 NTU reduced to less than 5 NTU in
      Thulokunuwar. The presence of dissolved iron contributes to arsenic
      removal processes by co-precipitation and adsorbing arsenic from
      solution. The filter can produce about 160-170 liters of water per
      day. The breakthrough points of these filters have not been observed
      for five months of continuous use. Therefore, the cost per liter of
      water could not be known. The other option at the household level is
      SORAS (Solar Oxidation for Removal of Arsenic), which is also very
      cheap method to remove the initial concentration of arsenic in the
      range of 100 to 150 mgL-1. The otherwise wasted PET bottles can be
      reused for the SORAS....


      Promotion of well-switching to mitigate the current arsenic crisis in
      Bangladesh. Alexander van Geen, Habibul Ahsan, Allan H. Horneman,
      Ratan K. Dhar, Yan Zheng, Iftikhhar Hussain, Kazi Matin Ahmed, Andrew
      Gelman, Martin Stute, H. James Simpson, Sean Wallace, Christopher
      Small, Faruque Parvez, Vesna Slavkovich, Nancy J. LoIacono, Marck
      Becker, Zhongqi Cheng, Hassina Momotaj, Mohammad Shahnewaz, Ashraf
      Ali Seddique, and Joseph H. Graziano. Bulletin of the World Health
      Organization 2002, 80 (9).

      Abstract: Objective - To survey tube wells and households in
      Araihazar upazila, Bangladesh, to set the stage for a long-term
      epidemiological study of the consequences of chronic arsenic
      exposure. Methods - Water samples and household data were collected
      over a period of 4 months in 2000 from 4997 contiguous tube wells
      serving a population of 55 000, the position of each well being
      determined to within + 30 m using Global Positioning System receivers
      Arsenic concentrations were determined by graphite-furnace
      atomic-absorption spectrometry In addition, groundwater samples
      collected every 2 weeks for an entire year from six tube wells were
      analysed for arsenic by high-resolution inductively coupled
      plasma-mass spectrometry. Findings - Half of the wells surveyed in
      Araihazar had been installed in the previous 5 years; 94% were
      privately owned. Only about 48% of the surveyed wells supplied water
      with an arsenic content below 50 ug/l, the current Bangladesh
      standard for drinking-water. Similar to other regions of Bangladesh
      and West Bengal, India, the distribution of arsenic in Araihazar is
      spatially highly variable (range: 5-860 ug/l) and therefore difficult
      to predict. Because of this variability, however, close to 90% of
      the inhabitants live within 100 m of a safe well. Monitoring of six
      tube wells currently meeting the 50 ug/l standard showed no
      indication of a seasonal cycle in arsenic concentrations coupled to
      the hydrological cycle. This suggests that well-switching is a
      viable option in Araihazar, at least for the short term. Conclusions
      - Well-switching should be more systematically encouraged in
      Araihazar and many other parts of Bangladesh and West Bengal, India.
      Social barriers to well-switching need to be better understood and,
      if possible, overcome.

      http://www3.interscience.wiley.com/cgi-bin/issuetoc?ID=78502921 [full
      text access, requires online subscription]

      Arsenic pollution of groundwater in Bangladesh. Kimiko Tanabe,
      Hiroshi Yokota, Hiromi Hironaka, Sachie Tsushima, Yoshihiro Kubota.
      Applied Organometallic Chemistry April 2001, 15(4) 241-251.
      Abstract: Arsenic concentrations in groundwater around the village
      of Samta, Jessore District, Bangladesh were measured. Distribution
      patterns of arsenic in groundwater were determined. Arsenic
      concentrations in drinking water tubewells mostly exceeded WHO

      Review article - chronic arsenic poisoning. Alan H. Hall. 2002,
      Toxicology Letters (in press).

      Abstract (uncorrected proof): Symptomatic arsenic poisoning is not
      often seen in occupational exposure settings. Attempted homicide and
      deliberate long-term poisoning have resulted in chronic toxicity.
      Skin pigmentation changes, palmar and plantar hyperkeratoses,
      gastrointestinal symptoms, anemia, and liver disease are common.
      Noncirrhotic portal hypertension with bleeding esophageal varices,
      splenomegaly, and hypersplenism may occur. A metallic taste,
      gastrointestinal disturbances, and Mee's lines may be seen. Bone
      marrow depression is common. 'Blackfoot disease' has been associated
      with arsenic-contaminated drinking water in Taiwan; Raynaud's
      phenomenon and acrocyanosis also may occur. Large numbers of persons
      in areas of India, Pakistan, and several other countries have been
      chronically poisoned from naturally occurring arsenic in ground
      water. Toxic delirium and encephalopathy can be present.
      CCA-treated wood (chromated copper arsenate) is not a health risk
      unless burned in fireplaces or woodstoves. Peripheral neuropathy may
      also occur. Workplace exposure or chronic ingestion of
      arsenic-contaminated water or arsenical medications is associated
      with development of skin, lung, and other cancers. Treatment may
      include the use of chelating agents such as dimercaprol (BAL),
      dimercaptosuccinic acid (DMSA), and dimercaptopanesulfonic acid

      Arsenic removal from contaminated water by the Soyatal Formation,
      Zimapán Mining District, Mexico - a potential low-cost low-tech
      remediation system. Ongley L.K.; Armienta M.A.; Heggeman K.; Lathrop
      A.S.; Mango H.; Miller W.; Pickelner S. Geochemistry: Exploration,
      Environment, Analysis, February 2001, vol. 1, no. 1, pp. 23-31(9)

      Abstract: The groundwater in Zimapán, Mexico has arsenic
      concentrations that range from below detection limits to >1 mg l-1.
      Rural residents of the valley need a low-cost, low-tech remediation
      process to reduce the arsenic concentrations to <50 µg l-1, the
      Mexican drinking water standard. Laboratory experiments show that
      the arsenic remediation potential of the Soyatal Formation, an
      ubiquitous clay-rich limestone, is superior to that of other rocks
      from the region. Experimentally contaminated water (ECW) was produced
      by reacting de-ionized water with tailings. The ECW (0.6 mg As l-1)
      was then reacted with various rocks from the Zimapán region.
      Although all rocks caused a decrease in the aqueous arsenic
      concentration, the arsenic concentration was below detection limits
      (<0.030 mg l-1) in any ECW that had been reacted with the Soyatal
      Formation. Other experiments established that a rock:water weight
      ratio of 1:10 can reduce the aqueous arsenic concentration in native
      water from 0.5 mg l-1 to <0.030 mg l-1. The calcareous shale of the
      Soyatal Formation contains kaolinite and illite. Both minerals are
      known to adsorb arsenic. The adsorptive characteristics of the
      Soyatal Formation may provide the basis for an acceptable low-cost
      low-tech remediation system.

      Arsenic poisoning in groundwater - health risk and geochemical
      sources in Bangladesh. H.M. Anawara, J. Akaib, K.M.G. Mostofac, S.
      Safiullahd, S.M. Tareqd. Environment International 27 (2002) 597-604.

      Abstract: Of the 2508 water samples analyzed in 10 districts of
      Bangladesh, 51%, on an average, contained arsenic levels of 0.05 to
      2.50 mg/l. 95% of nail, 96% of hair, and 94% of urine samples
      contained arsenic above the normal level. Approximately 3.58 million
      people out of a total of 17.92 million who are drinking water
      containing arsenic levels > 0.20 mg/l are potentially exposed to high
      risk of health hazard. Eight thousand and five hundred arsenic
      patients are identified; they are suffering from various skin
      lesions, gangrene in leg, skin, lung, bladder, liver, and renal
      cancer. A big portion of the total population is highly vulnerable
      to various internal cancers. Lowest arsenic concentration in
      drinking water producing dermatological disease is found to be 103
      ug/l. However, the exposure time to develop arsenicosis varies from
      case to case reflecting its dependence on arsenic level in drinking
      water and food, nutritional status, genetic variant of human being,
      and compounding factors. This study has determined the high
      intensity of fluorescent humic substances in drinking water
      containing elevated concentrations of arsenic and very low
      concentrations of heavy metals. The synergistic/antagonistic effect
      of fluorescent compounds present in drinking water may aggravate the
      toxicity of arsenic. Geochemical study suggests that arsenic may be
      released from both reductive dissolution of Fe and Mn (oxy)hydroxide
      and microbial oxidation of organic matter.

      Enhanced frequency of micronuclei in individuals exposed to arsenic
      through drinking water in West Bengal, India. A. Basu a, J. Mahata
      a, A.K. Roy b, J.N. Sarkar, G. Poddar, A. Nandi, P.K. Sarkar, P.K.
      Dutta, A. Banerjee, M. Dasd, K. Raya, S. Roychaudhury, A.T.
      Natarajan, R. Nilsson, A.K. Giri. Mutation Research 400416 (2002)

      Abstract: In West Bengal, India arsenic in ground water has been
      found to be above the maximum permissible limit in seven districts
      covering an area of 37,493 km2. In the present study, evaluation of
      the micronuclei (MN) formation in oral mucosa cells, urothelial cells
      and peripheral blood lymphocytes was carried out in the symptomatic
      individuals exposed to arsenic through drinking water. Forty five
      individuals with cutaneous signs of arsenicism from four affected
      districts (368.11ug/l of As in drinking water) were considered as the
      exposed group and 21 healthy individuals with no symptoms of arsenic
      poisoning and residing in two unaffected districts (5.49ug/l of As)
      were considered as controls. The exposed and control groups had
      similar age distribution and socioeconomic status. Standardised
      questionnaires were utilised and medical examination was conducted to
      ascertain exposure history, sociodemographic characteristics, diet,
      health, medication, addiction and chief symptoms in the study
      participants. Arsenic exposure was confirmed by measuring the
      arsenic content in the drinking water, nails, hair and urine samples
      from the volunteers. Arsenic contents in the urine, nail and hair in
      the exposed group were 24.45ug/l, 12.58 [sic], 6.97ug/g, respectively
      which were significantly high in comparison to corresponding control
      group values of 4.88ug/l, 0.51 [sic] and 0.34 g/g, respectively.
      Exposed individuals showed a statistically significant increase in
      the frequency of MN in oral mucosa, urothelial cells and lymphocytes
      (5.15, 5.74 and 6.39/1000 cells, respectively) when compared with the
      controls (0.77, 0.56 and 0.53/1000 cells, respectively). Thus, the
      above results indicate that the symptomatic individuals exposed to
      arsenic through drinking water in this region have significant
      cytogenetic damage.

      Flow injection hydride generation atomic absorption spectrometry for
      determination of arsenic in water and biological samples from
      arsenic-affected districts of West Bengal, India, and Bangladesh.
      Gautam Samanta, Tarit Roy Chowdhury, Badal K. Mandal, Bhajan K.
      Biswas, Uttam K. Chowdhury, Gautam K. Basu, Chitta R. Chanda, Dilip
      Lodh, and Dipankar Chakraborti. Microchemical Journal 62, 174-191

      Abstract: The increasing concern over human exposure to arsenic in
      West Bengal and Bangladesh has necessitated the development of a
      rapid method for determination of trace levels of arsenic in water
      and biological samples. We have developed a simple indigenous flow
      injection hydride generation atomic absorption spectrometry
      (FI-HG-AAS) system for the determination of arsenic in parts per
      billion levels in water and biological samples. The technique is
      fast, simple, and highly sensitive. The accuracy and precision of the
      method were evaluated by spiking known amounts of arsenic and
      analyzing different types of environmental and biological standard
      reference materials. The organic matter in a biological sample was
      destroyed by acid digestion and dry ashing technique. We analyzed
      thousands of tubewell water samples from the affected districts of
      West Bengal and Bangladesh. Most of the water samples contained a
      mixture of arsenite and arsenate and in none of them could we detect
      methylated arsenic. We also analyzed thousands of urine (inorganic
      arsenic and its metabolites), hair, and nail samples and hundreds of
      skin-scale and blood samples of people drinking arsenic-contaminated
      water and showing arsenical skin lesions. Quality control was
      assessed by interlaboratory analysis of hair samples. An
      understanding of arsenic toxicity and metabolism requires
      quantitation of individual arsenic species. The techniques we used
      for the determination and speciation of arsenic are (i) separation of
      arsenite and arsenate from water by sodium diethyldithiocarbamate in
      chloroform followed by FI-HG-AAS; (ii) determination of arsenite in
      citrate/citric buffer at pH 3 and total arsenic in water in 5 M HCl
      by FI-HG-AAS. Thus, arsenate is obtained from the difference; (iii)
      for analysis of inorganic arsenic and its metabolites in urine
      FI-HG-AAS was used after separation of the species with a combined
      cation-anion exchange column. Total arsenic in urine was also
      determined by FI-HG-AAS after acid decomposition. The species
      arsenite and arsenate are present in groundwater in about a 1:1 ratio
      and about 90% of the total arsenic in urine is present as inorganic
      arsenic and its metabolites.

      Combined effects of anions on arsenic removal by iron hydroxides.
      Xiaoguang Meng, George P. Korfiatis, Sunbaek Bang, Ki Woong Bang.
      Toxicology Letters (in press)

      Abstract (uncorrected proof): Batch experiments were conducted to
      investigate the combined effects of phosphate, silicate, and
      bicarbonate on the removal of arsenic from Bangladesh groundwater
      (BGW) and simulated groundwater by iron hydroxides. The apparent
      adsorption constants indicated that the affinity of the anions for
      iron hydroxide sites decreased in the following order arsenate >
      phosphate > arsenate > silicate > bicarbonate. Phosphate, silicate,
      and bicarbonate decreased the removal of As(III) even at relatively
      low concentrations and low surface site coverage. Phosphate (0-0.08
      mM), silicate (0-0.8 mM), and bicarbonate (0-14 mM) in separate
      solutions had none to moderate effects on As(V) removal in a solution
      containing 6.7 mg/l Fe and 0.3 ppm As(V). In the presence of
      bicarbonate and silicate the adverse effect of phosphate on As(V)
      adsorption was magnified. The residual As(V) concentration after
      iron hydroxide treatment increased from less than 13 ug/l in separate
      bicarbonate (2.2 mM) and phosphate (0.062 mM) solutions to 110 ug/l
      in the solution containing both anions. The results suggested the
      combined effects of phosphate, silicate, and bicarbonate caused the
      high mobility of arsenic in Bangladesh water.

      Epidemiologic evidence of diabetogenic effect of arsenic. Chin-Hsiao
      Tseng a, Ching-Ping Tseng, Hung-Yi Chiou, Yu-Mei Hsueh, Choon-Khim
      Chong, Chien-Jen Chen. Toxicology Letters (in press)

      Abstract (uncorrected proof): It is well documented that arsenic can
      lead to skin lesions, atherosclerotic diseases and cancers. The
      association between arsenic exposure and diabetes mellitus is a
      relatively new finding. Up to now, there are six epidemiologic
      reports linking diabetes mellitus with arsenic exposure from
      environmental and occupational sources. Two reports in Taiwan
      carried out in the blackfoot disease-hyperendemic villages, one
      cross-sectional and one prospective follow-up of the same cohort,
      indicate that arsenic exposure from drinking artesian well water is
      associated with prevalence and incidence of diabetes mellitus in a
      dose-responsive pattern. The observation of the relation between
      arsenic exposure and diabetes mellitus is further supported by
      studies carried out in Sweden and Bangladesh. In Sweden,
      case-control analyses of death records of copper smelters and glass
      workers revealed a trend of increasing diabetes mellitus with
      increasing arsenic exposure from inhalation. In Bangladesh,
      prevalence of diabetes mellitus among arsenic-exposed subjects with
      keratosis was about five times higher than unexposed subjects.
      Increasing trends of diabetes mellitus with indices of arsenic
      exposure in drinking water seems to be independent of the presence of
      skin lesions associated with arsenic exposure. Although these
      studies consistently show an association between arsenic exposure and
      diabetes mellitus, the weak study designs of cross-sectional or
      case-control, the use of glucosuria or diabetes death as diagnostic
      criteria and the lack of adjustment for possible confounders in some
      studies, are major limitations that may reduce the strength of the

      A review of the source, behaviour and distribution of arsenic in
      natural waters. P.L. Smedley*, D.G. Kinniburgh. Applied
      Geochemistry 17 (2002) 517-568.

      Abstract: The range of As concentrations found in natural waters is
      large, ranging from less than 0.5 ug l-1 to more than 5000 ug l-1.
      Typical concentrations in freshwater are less than 10 ug l-1 and
      frequently less than 1 ug l-1. Rarely, much higher concentrations
      are found, particularly in groundwater. In such areas, more than 10%
      of wells may be 'affected' (de?ned as those exceeding 50 ug l-1) and
      in the worst cases, this ?gure may exceed 90%. Well-known high-As
      groundwater areas have been found in Argentina, Chile, Mexico, China
      and Hungary, and more recently in West Bengal (India), Bangladesh and
      Vietnam. The scale of the problem in terms of population exposed to
      high As concentrations is greatest in the Bengal Basin with more than
      40 million people drinking water containing 'excessive' As. These
      large-scale 'natural' As groundwater problem areas tend to be found
      in two types of environment: ?rstly, inland or closed basins in arid
      or semi-arid areas, and secondly, strongly reducing aquifers often
      derived from alluvium. Both environments tend to contain
      geologically young sediments and to be in ?at, low-lying areas where
      groundwater ?ow is sluggish. Historically, these are poorly ?ushed
      aquifers and any As released from the sediments following burial has
      been able to accumulate in the groundwater. Arsenic-rich
      groundwaters are also found in geothermal areas and, on a more
      localised scale, in areas of mining activity and where oxidation of
      sulphide minerals has occurred. The As content of the aquifer
      materials in major problem aquifers does not appear to be
      exceptionally high, being normally in the range 1-20 mg kg-1. There
      appear to be two distinct 'triggers' that can lead to the release of
      As on a large scale. The ?rst is the development of high pH (>8.5)
      conditions in semi-arid or arid environments usually as a result of
      the combined effects of mineral weathering and high evaporation
      rates. This pH change leads either to the desorption of adsorbed As
      (especially As(V) species) and a range of other anion-forming
      elements (V, B, F, Mo, Se and U) from mineral oxides, especially Fe
      oxides, or it prevents them from being adsorbed. The second trigger
      is the development of strongly reducing conditions at near-neutral pH
      values, leading to the desorption of As from mineral oxides and to
      the reductive dissolution of Fe and Mn oxides, also leading to As
      release. Iron (II) and As(III) are relatively abundant in these
      groundwaters and SO4 concentrations are small (typically 1mg l-1 or
      less). Large concentrations of phosphate, bicarbonate, silicate and
      possibly organic matter can enhance the desorption of As because of
      competition for adsorption sites. A characteristic feature of high
      groundwater As areas is the large degree of spatial variability in As
      concentrations in the groundwaters. This means that it may be
      diffcult, or impossible, to predict reliably the likely concentration
      of As in a particular well from the results of neighbouring wells and
      means that there is little alternative but to analyse each well.
      Arsenic-affected aquifers are restricted to certain environments and
      appear to be the exception rather than the rule. In most aquifers,
      the majority of wells are likely to be unaffected, even when, for
      example, they contain high concentrations of dissolved Fe.

      Arsenic removal by reverse osmosis. Robert Y. Ning. Desalination
      143 (2002) 237-241.

      Arsenic is widely distributed in nature in air, water and soil. Acute
      and chronic arsenic exposure via drinking water has been reported in
      many countries, especially Argentina, Bangladesh, India, Mexico,
      Mongolia, Thailand and Taiwan, where a large proportion of ground
      water is contaminated with arsenic at levels from 100 to over 2,000
      micrograms per liter (ppb). Public health standards of maximum of 50
      ppb have been adopted by the US and World Health Organization in the
      1970s and the 80s. Carcinogenicity and genotoxicity led to the WHO
      recommendation of 10 ppb maximum level in 1993, followed by the US
      adoption of the same in 2001, with the US estimate that 5% of all US
      community water systems will have to take corrective actions to lower
      the current levels of arsenic in their drinking water. In high
      arsenic areas of the world, the need for better water treatment and
      resulting economic impact would be even greater. In this article, we
      briefly review the geochemistry, natural distribution, regulation,
      anthropogenic sources and removal mechanisms of arsenic, pointing
      especially to the promise of reverse osmosis (RO) as a practical
      means of purification. We conclude that arsenic in the commonly high
      oxidation states of (V) is very effectively removed by RO. With
      further attention to the removal of the weakly acidic arsenic (III)
      species in waters by the operation of RO at sufficiently high pHs
      made possible by the newer antiscalants, practical processes can be
      developed with RO to remove all major species of arsenic from water.
      Further studies are needed in the characterization of the arsenic
      species being treated and in the design of the RO process to match
      the demands.

      Arsenic calamity in the Indian subcontinent - What lessons have been
      learned? Dipankar Chakraborti a,*, Mohammad M. Rahman a, Kunal Paul
      a, Uttam K. Chowdhury a, Mrinal K. Sengupta a, Dilip Lodh a, Chitta
      R. Chanda a, Kshitish C. Saha b, Subhash C. Mukherjee. Talanta 58
      (2002) 3-22.

      Abstract: Groundwater arsenic (As) contamination in West Bengal (WB,
      India) was first reported in December 1983, when 63 people from three
      villages of two districts were identified by health officials as
      suffering from As toxicity. As of October 2001, the authors from the
      School of Environmental Studies (SOES) have analyzed >105 000 water
      samples, >25 000 urine/hair/nail/skin-scale samples, screened
      approximately 86 000 people in WB. The results show that more than 6
      million people from nine affected districts (total population
      approximately 42 million) of 18 total districts are drinking water
      containing >=50 ug l-1 As and >300 000 people may have visible
      arsenical skin lesions. 2 700 villages have so far been identified
      where groundwater contains arsenic above 50 Ug l-1. The As content of
      the physiological samples indicates that many more may be
      sub-clinically affected. Children in As-affected villages may be in
      special danger. In 1995, we had found three villages in two districts
      of Bangladesh where groundwater contained >=50 ug l-1 As. The present
      situation is that in 2000 villages in 50 out of total 64 districts of
      Bangladesh, groundwater contains As above 50 ug l-1 and more than 25
      million people are drinking water above >=50 ug l-1 As. After years
      of research in WB and Bangladesh, additional affected villages are
      being identified on virtually every new survey. The present research
      may still reflect only the tip of iceberg in identifying the extent
      of As contamination. Although the WB As problem became public almost
      20 years ago, there are still few concrete plans, much less
      achievements, to solve the problem. Villagers are probably in worse
      condition than 20 years ago. Even now, many who are drinking
      As-contaminated water are not even aware of that fact and its
      consequences. 20 years ago when the WB government was first informed,
      it was a casual matter, without the realization of the magnitude this
      problem was to assume. At least up to 1994, one committee after
      another was formed but no solution was forthcoming. None of the
      expert reports has suggested solutions that involve awareness
      campaigns, education of the villagers and participation of the
      people. Initially, international aid agencies working in the
      subcontinent simply did not consider that As could be present in
      groundwater. Even now, while As in drinking water is being
      highlighted, there have been almost no studies on how additional As
      is introduced through the food chain, as large amounts of As are
      present in the agricultural irrigation water. Past mistakes, notably
      the ceaseless exploitation of groundwater for irrigation, continue
      unabated today; at this time, more groundwater is being withdrawn
      than ever before. No efforts have been made to adopt effective
      watershed management to harness the extensive surface water and
      rainwater resources of this region. Proper watershed management and
      participation by villagers are needed for the proper utilization of
      water resources and to combat the As calamity. As in groundwater may
      just be nature's initial warning about more dangerous toxins yet to
      come. What lessons have we really learned?

      http://dchandra.hypermart.net/WRI10final.pdf (parent page is
      http://dchandra.hypermart.net/IJournals.HTML )

      Arsenic contamination in groundwater, Murshidabad district, West
      Bengal. D. Chandrasekharam & J. Karmakar, Z. Berner and D.
      Stüben. Water-Rock Interaction-10, Proceed. Villasimus, Italy,
      June 10-15,2001

      Abstract: Arsenic content in groundwater and surface waters from
      Murshidabad district of West Bengal varies from 0.05 to 3.7 mg/l.
      Arsenic was scavenged by Fe(III) minerals (primarily as iron
      oxyhydroxides), and to a lesser extent by Mn(IV) phases and is
      released into the groundwater due to lowering of the redox conditions
      in the aquifer system. Similarities in some trace element ratios of
      the Rajmahal traps with those of the arsenic contaminated
      groundwaters in this areas designates the Rajmahal traps as a
      possible primary source for the arsenic contamination.

      Arsenic contamination of the environment- a new perspective from
      central-east India. Piyush Kant Pandey *, Sushma Yadav, Sumita Nair,
      Ashish Bhui. Environment International 28 (2002) 235-245.

      Abstract: This paper reports a regional contamination of the
      environment in central-east India that does not share geology or
      boundary with the Bengal Delta Plain. About 30,000 people residing
      in 30 villages and towns are directly exposed to arsenic and more
      than 200,000 people are ''at risk.'' Complete geographical extent of
      this contamination is being established, and this newly reported
      contaminated area could be quite large. This paper further reports
      that the mechanisms involved in arsenic mobilisation are complex and
      the two theories of arsenic mobilisation, i.e., pyrite oxidation and
      oxyhydroxides reduction, do not fully explain the high levels of
      arsenic contamination. This paper also proposes the
      ''oxidation-reduction theory'' for arsenic mobilisation where the
      arsenic originates from the arsenopyrite oxidation and the arsenic
      thus mobilised forms the minerals and gets reduced underground in
      favourable Eh conditions. The stoppage of water withdrawal from the
      contaminated sources did not result in lowering of arsenic levels as
      expected according to the heavy groundwater extraction theory (pyrite
      oxidation theory). Cases of arsenicosis in the region are on the rise
      and the switchover to less contaminated water has not reversed the
      arsenicosis progression in the affected persons even after 2 years.
      Surface water of the rivers is also being contaminated because of the
      probable dislocation of contaminated groundwater due to the heavy
      rains in monsoon season, which indicates that the river water could
      be a major carrier of arsenic in dissolved or adsorbed forms that may
      be a cause of contamination of the delta plains.

      Arsenic contamination in groundwater: some analytical considerations.
      David G. Kinniburgh, Walter Kosmus. Talanta 58 (2002) 165-180

      For countries such as Bangladesh with a significant groundwater
      arsenic problem, there is an urgent need for the arsenic-contaminated
      wells to be identified as soon as possible and for appropriate action
      to be taken. This will involve the testing of a large number of
      wells, potentially up to 11 million in Bangladesh alone. Field-test
      kits offer the only practical way forward in the timescale required.
      The classic field method for detecting arsenic (the 'Gutzeit' method)
      is based on the reaction of arsine gas with mercuric bromide and
      remains the best practical approach. It can in principle achieve a
      detection limit of about 10 ug l-1 by visual comparison of the
      coloured stain against a colour calibration chart. A more objective
      result can be achieved when the colour is measured by an electronic
      instrument. Attention has to be paid to interferences mainly from
      hydrogen sulfide. Due to analytical errors, both from the field-test
      kits and from laboratory analysis, some misclassification of wells is
      inevitable, even under ideal conditions. The extent of
      misclassification depends on the magnitude of the errors of analysis
      and the frequency distribution of arsenic observed, but is in
      principle predictable before an extensive survey is undertaken. For
      a country with an arsenic distribution similar to that of Bangladesh,
      providing care is taken to avoid sources of bias during testing,
      modern field-test kits should be able to reduce this
      misclassification to under 5% overall

      Role of iron in controlling speciation and mobilization of arsenic in
      subsurface environment. Purnendu Bose and Archana Sharma. Water
      Research, in press.

      Abstract: Widespread arsenic contamination of groundwater has been
      reported of late in Bangladesh and West Bengal state of India. On the
      basis of arsenic geochemistry, three probable mechanisms have been
      cited for arsenic mobility in aquifers of West Bengal and Bangladesh.
      First, mobilization of arsenic due to the oxidation of
      arsenic-bearing pyrite minerals. Second, dissolution of
      arsenic-contaminated iron oxy-hydroxides (FeOOH) due to onset of
      reducing conditions in the subsurface. Third, due to the release of
      arsenic sorbed to aquifer minerals by competitive exchange with
      phosphate ions, that migrates into aquifers due to application of
      fertilizer to surface soil. Based on the reviewof .eld data from the
      affected region, it appears that the second mechanism described above
      is the most probable. Two reduction processes associated with this
      mechanism were investigated, viz., reduction of iron oxy-hydroxide to
      iron (II), which results in the mobilization of arsenic, and
      reduction of arsenic (V) to arsenic (III), which may enhance mobility
      of arsenic under certain conditions. These reactions, in the opinion
      of some researchers, are possible in subsurface environments mainly
      through microbial intervention. However, through the data presented
      in this paper, it has been demonstrated that above red-ox reactions
      involving iron and arsenic are also possible through predominantly
      abiotic pathways. While these results do not necessarily imply that
      abiotic red-ox processes are dominant in all subsurface environments
      containing iron and arsenic, it is entirely possible that abiotic
      interactions as described <br/><br/>(Message over 64 KB, truncated)
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