Lead contamination and its remediation

1. LEAD CONTAMINATION AND ITS
REMEDIATION
Presented by
ANASUYA KARMAKAR
CLASS- B.C.E, 3RD YEAR (2014-15)
SECTION-B2
ROLL NO-001210401081
Under the guidance of
Dr. ANUPAM DEBSARKAR
Department of Civil Engineering
Jadavpur University

2. CONTENTS
INTRODUCTION
SOURCES OF LEAD IN WATER
ADVERSE EFFECTS OF LEAD LEAD CONTAMINATION IN WATER
CASE STUDIES ON LEAD
CONTAMINATION
REMEDIATION OF LEAD
CONTAMINATED WATER
CONCLUSION

3.  Lead contamination of water is the toxicity of lead that are relevant to
the estimation of a public health protective level in drinking water.
 Thirty three percent of over 370 samples of water from the top 26
cities of India tested positive for harmful content of lead.
 In 2004, 143,000 deaths and a loss of 8,977,000 disease adjusted life
years were attributed to lead exposure worldwide, primarily from lead-
associated adult cardiovascular disease and mild intellectual disability
in children.
 As per various surveys and investigations conducted by organizations
such as the ‘Quality Council of India,’ the presence of ‘lead in water’ has
alarmed people and agencies across the country.
INTRODUCTION

4. SOURCES OF LEAD IN WATER
 Lead dissolves in water from natural sources such as rock and soil . So it is
unlikely present in raw water.
 From household plumbing systems in which the pipes, solder, fittings or
service connections to homes contain lead. Polyvinyl chloride (PVC) pipes
also contain lead compounds that can be leached from them and result in
high lead concentrations in drinking-water.
 Lead can also be released from flaking lead carbonate deposits on lead pipe
and from iron sediment from old galvanized plumbing that has accumulated
lead from lead sources such as plumbing and service connections, even when
the water is no longer plumb solvent.
 Corrosive water can increase the amount of lead in drinking water.
Corrosive water can be caused by high acidity or low mineral content. Acidic
water tends to dissolve lead from pipes into water.

5. SOURCES OF LEAD IN WATER
 Occupational exposure, such as from lead smelting, soldering and battery
manufacturing, and exposure from hobbies, such as stained glass making, can
also be a source of lead.
 A small number of cosmetic products have been found to contain significant
amounts of lead.
 Food can contain small amounts of lead. Food is the major source of exposure to
lead for the majority of the population in Europe.
 Lead content can be increased when the water used for cooking, or the cooking
utensils, contain lead or when the food, especially if acidic, has been stored in
lead-ceramic pottery ware or lead-soldered cans.

6. ADVERSE EFFECTS OF LEAD
 The health consequences of lead exposure depend on the cumulative dose
of lead and vulnerability of the individual person rather than the
environmental media (i.e., food, water, soil, dust, or air) in which the lead
exists.
 Recent evidence suggests that the dose-effect relationship might be
superlinear, with a steeper dose response and potential risk for an adverse
health effect such as IQ loss at BLLs <10 µg/dl compared with BLLs ≥10
µg/dl in case of children.
 Adults with occupational exposure to lead report more colds and
influenza and exhibit suppressed secretory immunoglobulin A (IgA)
levels, demonstrating lead induced suppression of humeral immunity.

7. ADVERSE EFFECTS OF LEAD
 Motor nerve dysfunction can occur at BLLs as low as 40µg/dl. Lead also is
nephrotoxic and can cause progressive nephron loss leading to renal failure,
gout, and hypertension.
 The increment in the percentage of lead in water also causes cancer.
 Disturbances in cardiac conduction and rhythm and increase in blood
pressure; hepatic damage; anemia and other hematological effects,
reproductive and developmental toxicity, gastrointestinal disturbance.
 Research on young primates has demonstrated that exposure to lead results in
significant behavioral and cognitive deficits, such as impairment of activity,
attention, adaptability, learning ability and memory.

8. LEAD CONTAMINATION IN WATER
 Lead is a poisonous metal. Lead ions are being released into the environment
due to industrial activity and technological development.
 This poses a significant threat to the environment and public health because
of toxicity, incremental accumulation in the food chain and persistence in the
ecosystem.
 Young children, those 6 years and younger, are at particular risk for lead
exposure because they have frequent hand-to-mouth activity and absorb lead
more easily than do adults.
 No safe blood lead level in children has been determined. Lead can affect
almost every organ and system in our body. The most sensitive is the central
nervous system (brain), particularly in children.

9. LEAD CONTAMINATION IN WATER
 Low blood levels of lead (those below 10 µg/dl) have been associated
with reduced IQ and attention span, learning disabilities, poor
classroom performance, hyperactivity, behavioral problems,
impaired growth, and hearing loss.
 Very high lead level (blood lead levels above 70 µg/dl) can cause
severe neurological problems such as coma, convulsions, and even
death.

10. CASE STUDIES
CASE STUDY-1
LEAD CONTAMINATION IN CANADA
 Population blood lead levels show a significant decrease, most notably since the
phase out of lead gasoline.
 Pathways of exposure still exist such as through house dust and dirt, old paint
chips and drinking water distribution systems.
 Drinking water can account for 10-20% of lead exposure in children and adults,
and 40-60% in infants consuming formula made with drinking water containing
lead.
 Households with drinking water lead concentrations ≥ 10 ug/l will be provided
with information on ways to reduce lead exposure including the use of certified
water filters.

11. CASE STUDY-2
LEAD CONTAMINATION IN SCHOOL
 Schools were sampled in 1991 and 1992 in response to the Lead Contamination Control
Act. Drinking fountains with lead levels over 20 ppb were replaced.
 Lead levels over 20 ppb were found at 25% of the locations. One location was 1600
ppb.
 The water supplied by the local public water system was found to have typically less
than 1 ppb lead and was ruled out as a source of lead.
 The district adopted a policy for mitigation that included a target level of 10 ppb for
lead. Additionally, the EPA public water supply standards for cadmium, copper, iron
and coliform bacteria were adopted.
 Fountains and other outlets that produce lead analysis results higher than 10 ppb will
be fixed or disabled. Fixtures with confirmed levels of iron will be fixed or removed
from service
CASE STUDIES

12. REMEDIATION OF LEAD
CONTAMINATED WATER
 ION EXCHANGE
 The principals of the ion exchange process is naturally related to water
softening.
 Sodium ions were exchanged for calcium and magnesium ions on an
equivalent basis and there was no decrease in dissolved solids.
 For demineralization, however the exchanged ions must not contribute
dissolved solids to the effluent, this is accomplished by exchanging hydrogen
for the dissolved cat ions and hydroxide for the dissolved anions.

13. REMEDIATION OF LEAD
CONTAMINATED WATER
ADSORPTION
 In physical adsorption The concentration of gases and vapors on solids at
temperature above dew point, depends upon Vander-Waals force(an
intermolecular attractive force).
 The amount of gas adsorbed relates to the ease of condensation of the gas-the
higher the boiling point, the greater the amount adsorbed.
 In chemical adsorption the contaminant gas molecule forms a chemical bond
with the adsorbents, and the gas is held strongly to the solid surface by valence
forces.

14. CONCLUSION
 Lead levels are extremely high in several drinking water sources in the
industrial cities. This is particularly alarming in ground water sources,
almost all of which had higher lead concentrations that the WHO
acceptable limit of 10 ppb.
 Mean lead quantity was > 150 ppb in the ground water sources in many
countries of the world. There is a need for further investigation of sources
of lead in drinking water supplies in the city and for detailed inspection of
water samples to be carried out in every area.
 In the worse affected districts there may be a need for cessation of some of
the water sources to prevent the adverse consequences of lead toxicity in
the public.

15. REFERENCES
 Robert M. Brooks Temple University, Mozhgan Bahadory Temple
 University,Fernando To via, Philadelphia University,Hossein Rostami
 Philadelphia University, rostamih@philau.edu, REMOVAL OF LEAD FROM
CONTAMINATED WATER, article: 14.
 M.N.Murty,Surender Kumar, Water Pollution in India an Economic Appraisal
 Guidance package for Water Utility Companies, Residents, Alberta Health
Services, Healthcare Providers, and Laboratories, Lead and Drinking Water
from Lead Service Lines (2013)
 Background document for development of WHO Guidelines for Drinking-
water Quality , Lead in Drinking Water

16. THANK YOU