Bikas Vaidya

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Rapid Detection of Arsenic in Water

• Bikas Vaidya

Small Business Water Innovation - An Integrated
Approach to Sustainable Solutions Session II -
Innovative Detection Technologies March 23,
2016
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Arsenic in Water

• Arsenic in drinking water poses a serious health
  hazard to tens of millions of people, especially
  in parts of the world where the arsenic
  concentrations far exceed the 10 ppb guideline
  value set by WHO.

Global occurrences of arsenic in groundwater
B. Panda, Int. J. of Ecosystem 2015, 5(3A) 75-85
B.
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Arsenic Detection

• Arsenic in drinking water poses a serious health
  hazard to tens of millions of people in different
  parts of the world.
• Rapid and reliable testing to distinguish wells
  with high and low arsenic levels is critical.
• Conventional methods for determination of
  arsenic, such as ICP-MS and ICP-AES, are time
  consuming, and expensive, while colorimetric
  tests are not reliable.
• Colorimetric test kits use highly toxic chemicals
  containing mercury or lead and also produce
  highly toxic arsine gas during the test.
• Lynntech is developing a rapid, reliable and
  convenient test kit for quantitative
  determination of arsenic in water samples without
  using toxic chemicals or metals.

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Lynntech Approach

• Simple handheld system that utilizes disposable
  cartridges for rapid detection of arsenic in
  water.
• Disposable dry cartridge consisting of two blocks
  (reagent block and detection block) and
  eliminates the need for handling any corrosive or
  toxic chemicals.
• A simple colorimeter used for quantification.

1. Pass water sample through the test cartridge. 2. Attach the detection cartridge block to a colorimeter and take reading.
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Preliminary Results
0 ppb 5 ppb 10 ppb 20
ppb Water samples with higher concentration of
arsenic produced deeper green coloration.
Reagent (top) and detection (bottom) blocks used
for detection of arsenic.
Reflectance absorption spectra for the samples
containing 0, 5, 10 and 20 ppb As.
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Features and Benefits

• Detection of both As(III) and As(V).
• Quantitative. A handheld colorimeter used for
  quantification.
• Rapid. Result within minutes.
• Simple. Does not require a skilled operator.
• Safe. Spent reagents are neutralized for
  convenient disposal.
• Green. Does not use toxic metals like mercury or
  lead.
• Reactions occur in a prepackaged flow through
  cartridge minimizing reagent handling and
  operator error.
• Long shelf life. Uses dry (stable) reagents in
  disposable cartridges.
• Inclusion of a step to remove phosphate.

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Acknowledgement and Contact Info.

• This research is funded by
• The Superfund Research Program
• The National Institute of Environmental Health
  Sciences
• National Institutes of Health (R43 ES025466-01)

• Contact
• Bikas Vaidya
• bikas.vaidya_at_lynntech.com
• 979-764-2299

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