The Silent Pandemic Caused by The Silent Pandemic Caused by Drinking Metals in Deep Well WaterDrinking Metals in Deep Well Water

Copyright Copyright ©© 2011 Seth H. Frisbie, Ph.D. All rights reserved. 2011 Seth H. Frisbie, Ph.D. All rights reserved.

Erika Mitchell, Ph.D.Erika Mitchell, Ph.D.

Bibudhendra Sarkar, Ph.D.Bibudhendra Sarkar, Ph.D.

Seth Frisbie, Ph.D.Seth Frisbie, Ph.D.

Donald Maynard, P.E. Donald Maynard, P.E.

A History of Drinking WaterA History of Drinking Water• Since the beginning of human Since the beginning of human

history until very recently, we history until very recently, we have used only surface or dug have used only surface or dug well water for drinking.well water for drinking.

• In 1862 the tubewell was In 1862 the tubewell was invented by Col. Nelson W. invented by Col. Nelson W. Green and deep well water Green and deep well water became easily accessible for became easily accessible for drinking.drinking.

• Today billions of people use Today billions of people use deep well water for drinking.deep well water for drinking.

(Photograph by Peer (Photograph by Peer Water Exchange, 2006)Water Exchange, 2006)

(Col. Nelson W. Green)(Col. Nelson W. Green)

• Surface and dug well water Surface and dug well water often has microorganisms often has microorganisms that can make a person sick that can make a person sick hours or days after drinking.hours or days after drinking.

• High dissolved oxygen (OHigh dissolved oxygen (O22) )

and the removal of ions by and the removal of ions by leaching gives surface and leaching gives surface and dug well water low dug well water low concentrations of arsenic concentrations of arsenic (As), manganese (Mn), and (As), manganese (Mn), and other metals.other metals.

(Photograph of (Photograph of Vibrio choleraVibrio cholera by Jozef Rosinský)by Jozef Rosinský)

A History of Drinking WaterA History of Drinking Water

• In contrast, deep well water rarely has pathogenic In contrast, deep well water rarely has pathogenic microorganisms.microorganisms.

• Low dissolved OLow dissolved O22 and the accumulation of ions and the accumulation of ions

from leaching gives deep well water high from leaching gives deep well water high concentrations of As, Mn, and other metals that concentrations of As, Mn, and other metals that can make a person sick after years or decades of can make a person sick after years or decades of regular drinking.regular drinking.

(Images by Element Collection, Inc.)(Images by Element Collection, Inc.)

• The diagnosis of The diagnosis of chronic metal poisoning chronic metal poisoning is made difficult by the is made difficult by the 5 to 20 or more years of 5 to 20 or more years of exposure needed to exposure needed to produce symptoms.produce symptoms.

A History of Drinking WaterA History of Drinking Water

A History of Drinking Water in ArgentinaA History of Drinking Water in Argentina• In the 1880s tubewells were first used in Northern In the 1880s tubewells were first used in Northern

Argentina.Argentina.• In 1916 Dr. Abel Ayerza found that both people and In 1916 Dr. Abel Ayerza found that both people and

chickens had symptoms similar to pharmaceutical chickens had symptoms similar to pharmaceutical As poisoning.As poisoning.

• Later, Ayerza checked things in common and Later, Ayerza checked things in common and found As and vanadium (V) in the drinking water.found As and vanadium (V) in the drinking water.

(Photographs by Ayerza, 1918)(Photographs by Ayerza, 1918)

• Many premature deaths were caused by drinking Many premature deaths were caused by drinking surface water.surface water.

• The life expectancy during the mid-1960s was only The life expectancy during the mid-1960s was only 46 years.46 years.

A History of Drinking Water in BangladeshA History of Drinking Water in Bangladesh• Rivers, ponds, and dug Rivers, ponds, and dug

wells were the only wells were the only practical source of practical source of drinking water from at drinking water from at least 900 BC until the least 900 BC until the 1970s.1970s.

• A massive cholera A massive cholera outbreak began in outbreak began in 1963.1963. (Photograph by Dhaka Hospital)(Photograph by Dhaka Hospital)

• Approximately 10,000,000 Approximately 10,000,000 tubewells have been tubewells have been installed since 1971 to installed since 1971 to supply safe drinking water.supply safe drinking water.

• Within 1 generation the Within 1 generation the population changed from population changed from drinking surface water to drinking surface water to drinking groundwater.drinking groundwater.

• By 2000, approximately By 2000, approximately 97% of Bangladeshis drank 97% of Bangladeshis drank tubewell water.tubewell water.

(Photograph by Steven Brace, 1995)(Photograph by Steven Brace, 1995)

A History of Drinking Water in BangladeshA History of Drinking Water in Bangladesh

• The symptoms of The symptoms of chronic As poisoning chronic As poisoning from drinking water from drinking water usually take 5 to 20 usually take 5 to 20 years to manifest.years to manifest.

• Chronic As poisoning Chronic As poisoning from drinking tubewell from drinking tubewell water was first water was first diagnosed in 1993.diagnosed in 1993.

Melanosis of the chestMelanosis of the chest

Keratosis of the palmsKeratosis of the palms(Photograph by Dhaka Community (Photograph by Dhaka Community Hospital and Richard Wilson, 2002)Hospital and Richard Wilson, 2002)

Keratosis of the feetKeratosis of the feet

Blackfoot diseaseBlackfoot disease

A History of Drinking Water in BangladeshA History of Drinking Water in Bangladesh

• The first national-scale The first national-scale map of As concentration map of As concentration in Bangladesh’s tubewell in Bangladesh’s tubewell water was made in 1997.water was made in 1997.

• Approximately Approximately 75,000,000 Bangladeshis 75,000,000 Bangladeshis are at risk of death from are at risk of death from skin, bladder, liver, and skin, bladder, liver, and lung cancers caused by lung cancers caused by chronic As poisoning.chronic As poisoning.

• The source of As is The source of As is geological.geological.

Map of As Map of As concentration (mg/L).concentration (mg/L).

A History of Drinking Water in BangladeshA History of Drinking Water in Bangladesh

The Discovery of Other Toxic Elements in The Discovery of Other Toxic Elements in Bangladesh’s Drinking WaterBangladesh’s Drinking Water

AnalyteAnalyte IndependentIndependentStandard RecoveryStandard Recovery(Analyte Added to (Analyte Added to

Distilled Water)Distilled Water)

Sample Matrix Sample Matrix Spike RecoverySpike Recovery

(Analyte Added to (Analyte Added to Drinking Water)Drinking Water)

Arsenic (As)Arsenic (As) 83%83% 89 89 11% 11%

Ferrous iron (FeFerrous iron (Fe2+2+)) 93 93 10% 10% 34 34 23% 23%

Total iron (Fe)Total iron (Fe) 95%95% Not measured, at least 27% of Not measured, at least 27% of samples developed the wrong color.samples developed the wrong color.

• At least 27% of the drinking water wells in Bangladesh At least 27% of the drinking water wells in Bangladesh apparently contain an analytical interference to the 1,10-apparently contain an analytical interference to the 1,10-phenanthroline methods for measuring ferrous iron and phenanthroline methods for measuring ferrous iron and total iron.total iron.

The Discovery of Other Toxic Elements in The Discovery of Other Toxic Elements in Bangladesh’s Drinking WaterBangladesh’s Drinking Water

• In addition, the early onset of In addition, the early onset of chronic As poisoning chronic As poisoning suggested that multimetal suggested that multimetal health effects are possible.health effects are possible.

• The problems measuring The problems measuring iron and the early onset of iron and the early onset of chronic As poisoning were chronic As poisoning were the first evidence that other the first evidence that other toxic elements are widely toxic elements are widely distributed in Bangladesh’s distributed in Bangladesh’s drinking water.drinking water.

(Photograph by NGO Forum, 2002)(Photograph by NGO Forum, 2002)

• 60% of Bangladesh’s area contains groundwater with Mn 60% of Bangladesh’s area contains groundwater with Mn concentrations greater than the WHO drinking water guideline.concentrations greater than the WHO drinking water guideline.

• Manganese in drinking water is a potent neurotoxin, associated with Manganese in drinking water is a potent neurotoxin, associated with violent behaviors and depression. It causes learning disabilities in violent behaviors and depression. It causes learning disabilities in children and Parkinson's-like symptoms in adults.children and Parkinson's-like symptoms in adults.

• It causes liver and kidney damage, and is associated with hearing loss.It causes liver and kidney damage, and is associated with hearing loss.

Map of Mn concentration (mg/L).Map of Mn concentration (mg/L).

• 3% of Bangladesh’s area contains groundwater with Pb concentrations 3% of Bangladesh’s area contains groundwater with Pb concentrations greater than the WHO drinking water guideline.greater than the WHO drinking water guideline.

• Lead is a potent neurotoxin, associated with IQ deficits and learning Lead is a potent neurotoxin, associated with IQ deficits and learning disabilities in children and dementia in adults.disabilities in children and dementia in adults.

• It is also associated with kidney, liver, and heart disease, tooth loss, It is also associated with kidney, liver, and heart disease, tooth loss, cataracts, hypertension, diabetes, and bladder cancer.cataracts, hypertension, diabetes, and bladder cancer.

Map of lead (Pb) concentration (mg/L).Map of lead (Pb) concentration (mg/L).

• < 1% of Bangladesh’s area contains groundwater with Ni < 1% of Bangladesh’s area contains groundwater with Ni concentrations greater than the WHO drinking water guideline.concentrations greater than the WHO drinking water guideline.

• Nickel is a potent carcinogen.Nickel is a potent carcinogen.• It is also associated with lung, heart, and kidney disease and can It is also associated with lung, heart, and kidney disease and can

induce spontaneous abortions.induce spontaneous abortions.

Map of nickel (Ni) concentration (mg/L).Map of nickel (Ni) concentration (mg/L).

• < 1% of Bangladesh’s area contains groundwater with Cr < 1% of Bangladesh’s area contains groundwater with Cr concentrations greater than the WHO drinking water guideline.concentrations greater than the WHO drinking water guideline.

• Cr(III) is the form most often found in drinking water. Chronic Cr(III) is the form most often found in drinking water. Chronic exposure inhibits DNA synthesis and the fidelity of DNA replication. exposure inhibits DNA synthesis and the fidelity of DNA replication.

• Cr(III) accumulates in the liver; persons with existing liver disease may Cr(III) accumulates in the liver; persons with existing liver disease may be exceptionally susceptible to its toxic effects.be exceptionally susceptible to its toxic effects.

Map of total chromium (Cr) concentration (mg/L).Map of total chromium (Cr) concentration (mg/L).

aa Assuming Bangladesh has 158,570,535 people (July 2011 est.) and 97% of its Assuming Bangladesh has 158,570,535 people (July 2011 est.) and 97% of its population drinks well water.population drinks well water.

Estimated number of Bangladeshis drinking water Estimated number of Bangladeshis drinking water with metal concentrations above WHO guidelines.with metal concentrations above WHO guidelines.

MetalMetal Carcinogenic Carcinogenic PotentialPotential

WHO WHO Guideline Guideline

(µg/L)(µg/L)

Percent of Percent of Bangladesh’s Area Bangladesh’s Area

Exceeding WHO Exceeding WHO GuidelineGuideline

Number of Number of Bangladeshis Bangladeshis

Drinking Unsafe Drinking Unsafe Water Water aa

AsAsMnMnPbPbNiNiCrCr

Known carcinogenKnown carcinogenNoncarcinogenNoncarcinogenPossible carcinogenPossible carcinogenProbable carcinogenProbable carcinogenNoncarcinogenNoncarcinogen

1010400400101020205050

4949606033

< 1< 1< 1< 1

75,000,00075,000,00092,000,00092,000,000

4,600,0004,600,000< 1,500,000< 1,500,000< 1,500,000< 1,500,000

• Tens of millions of Bangladeshis are drinking water that Tens of millions of Bangladeshis are drinking water that exceeds WHO health-based guidelines for As, Mn, Pb, Ni, exceeds WHO health-based guidelines for As, Mn, Pb, Ni, and Cr.and Cr.

• Chronic As poisoning is the most significant health risk.Chronic As poisoning is the most significant health risk.• Multimetal health effects are possible.Multimetal health effects are possible.

Climate Change and Multimetal Climate Change and Multimetal Exposure in BangladeshExposure in Bangladesh

• Most of Bangladesh is Most of Bangladesh is less than 12 meters less than 12 meters above sea level.above sea level.

• In a normal monsoon In a normal monsoon season one-third of the season one-third of the cultivated land is cultivated land is flooded with a mixture flooded with a mixture of fresh and saltwater.of fresh and saltwater. (Photograph by Louise Gray, 2009)(Photograph by Louise Gray, 2009)

• Flooding will likely increase the concentrations of Flooding will likely increase the concentrations of As, Mn, and other metals by creating a reducing As, Mn, and other metals by creating a reducing environment and by ion exchange.environment and by ion exchange.

Graph of As concentration (mg/L) Graph of As concentration (mg/L) versus oxidation-reduction potential versus oxidation-reduction potential

(mV).(mV).

0.000

0.100

0.200

0.300

0.400

0.500

-200 -100 0 100 200 300

Oxidation-Reduction Potential (mV)

Ars

en

ic C

on

ce

ntr

ati

on

(m

g/L

)

Climate Change and Multimetal Climate Change and Multimetal Exposure in BangladeshExposure in Bangladesh

• This graph suggests This graph suggests that As is released from that As is released from solids to Bangladesh’s solids to Bangladesh’s groundwater by groundwater by reduction.reduction.

• If so, it is likely that If so, it is likely that flooding would also flooding would also release a wide variety release a wide variety of other ions into of other ions into groundwater by groundwater by creating a reducing creating a reducing environment.environment.

Map of As concentration (mg/L).Map of As concentration (mg/L). Map of ClMap of Cl-- concentration (mg/L). concentration (mg/L).

• These maps suggest this saltwater intrusion might release arsenite These maps suggest this saltwater intrusion might release arsenite (H(H3-x3-xAs(III)OAs(III)O33

x-x-) or arsenate (H) or arsenate (H3-x3-xAs(V)OAs(V)O44x-x-) from solids to Bangladesh’s ) from solids to Bangladesh’s

groundwater by anion exchange with chloride (Clgroundwater by anion exchange with chloride (Cl--).).• If so, it is likely that saltwater intrusion would also release a wide If so, it is likely that saltwater intrusion would also release a wide

variety of other ions into groundwater by both anion and cation variety of other ions into groundwater by both anion and cation exchange.exchange.

Satellite image of Bongaon, Satellite image of Bongaon, West Bengal, India.West Bengal, India.

A Discovery of Multimetal Exposure in IndiaA Discovery of Multimetal Exposure in India

Map of As, Mn, and boron (B) Map of As, Mn, and boron (B) concentrations (µg/L).concentrations (µg/L).

• As, Mn and B As, Mn and B were found were found above WHO above WHO health-based health-based drinking water drinking water guidelines in guidelines in 50%, 19% and 50%, 19% and 6% of 6% of tubewells, tubewells, respectively.respectively.

• The unsafe The unsafe concentrations concentrations are shown in are shown in yellow.yellow.

A Discovery of Multimetal Exposure in IndiaA Discovery of Multimetal Exposure in India

• Pb in nature is a mixture of 4 stable isotopes: Pb in nature is a mixture of 4 stable isotopes: 204204Pb (1.48%), Pb (1.48%), 206206Pb (23.6%), Pb (23.6%), 207207Pb (22.6%), and Pb (22.6%), and 208208Pb (52.3%).Pb (52.3%).

• Of these 4 isotopes, only Of these 4 isotopes, only 204204Pb is not a radiogenic nuclide.Pb is not a radiogenic nuclide.• The Uranium Series starts with The Uranium Series starts with 238238U and ends with U and ends with 206206Pb.Pb.• The Actinium Series starts with The Actinium Series starts with 235235U and ends with U and ends with 207207Pb.Pb.• The Thorium Series starts with The Thorium Series starts with 232232Th and ends with Th and ends with 208208Pb.Pb.

• Therefore, more than 98% of Pb is from the radioactive Therefore, more than 98% of Pb is from the radioactive decay of decay of 238238U, U, 235235U, and U, and 232232Th.Th.

• Pb, U, and Th are in this village’s drinking water.Pb, U, and Th are in this village’s drinking water.• There are WHO drinking water guidelines for Pb and U.There are WHO drinking water guidelines for Pb and U.• There is no WHO drinking water guideline for Th.There is no WHO drinking water guideline for Th.

A Discovery of Multimetal Exposure in IndiaA Discovery of Multimetal Exposure in India

Known regions of natural multimetal contamination in deep well water.Known regions of natural multimetal contamination in deep well water.

• Billions of people use deep well water for drinking.Billions of people use deep well water for drinking.• However, very few However, very few systematicsystematic surveys of multiple metals in surveys of multiple metals in

deep well water have been done at a national or regional-deep well water have been done at a national or regional-scale.scale.

• More of these surveys are needed.More of these surveys are needed.

A First Challenge for Drinking Water ChemistsA First Challenge for Drinking Water Chemists

No.No. Ele.Ele. ppmppm No.No. Ele.Ele. ppmppm No.No. Ele.Ele. ppmppm No.No. Ele.Ele. ppmppm

112233445566778899

1010111112121313141415151616171718181919

OOSiSiAlAlFeFeCaCaMgMgNaNaKKTiTiHHPP

MnMnFF

BaBaSrSrSSCCZrZrVV

455,000455,000272,000272,00083,00083,00062,00062,00046,60046,60027,64027,64022,70022,70018,40018,4006,3206,3201,5201,5201,1201,1201,0601,060544544390390384384340340180180162162136136

2020212122222323242425252626272728282929303031313232

33a33a33b33b3535363637373838

ClClCrCrNiNiRbRbZnZnCuCuCeCeNdNdLaLaYY

CoCoScScNbNbNN

GaGaLiLiPbPbPrPrBB

1261261221229999787876766868666640403535313129292525202019191919181813139.19.199

393940404141424243434444454546464747

48a48a48b48b50505151525253535454

55a55a55b55b55c55c

ThThSmSmGdGdErErYbYbHfHfCsCsBrBrUU

SnSnEuEuBeBeAsAsTaTaGeGeHoHoMoMoWWTbTb

8.18.17.07.06.16.13.53.53.13.12.82.82.62.62.52.52.32.32.12.12.12.122

1.81.81.71.71.51.51.31.31.21.21.21.21.21.2

585859596060616162626363

64a64a64b64b666667676868696970707171

72a72a72b72b7474

75a75a75b75b

TlTlTmTm

IIInInSbSbCdCdAgAgHgHgSeSePdPdPtPtBiBiOsOsAuAuIrIrTeTeReReRuRuRhRh

0.70.70.50.5

0.460.460.240.240.20.2

0.160.160.080.080.080.080.050.05

0.0150.0150.010.01

0.0080.0080.0050.0050.0040.0040.0010.0010.0010.001

0.00070.00070.00010.00010.00010.0001

A Second Challenge for Drinking Water ChemistsA Second Challenge for Drinking Water ChemistsAbundance of elements in the earth’s crust.Abundance of elements in the earth’s crust.

Elements with WHO drinking water guidelines are red.Elements with WHO drinking water guidelines are red.

• Only 16 of 76 (21%) elements in the earth’s crust have a WHO drinking Only 16 of 76 (21%) elements in the earth’s crust have a WHO drinking water guideline. Many of the remaining elements are toxic and water guideline. Many of the remaining elements are toxic and commonly found in groundwater. More guidelines are needed.commonly found in groundwater. More guidelines are needed.

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