Transcript Welcome to Lecture- 04

Lecture # 16: Arsenic contamination in BD
Objectives
1.
2.
3.
4.
5.
To Define Arsenicosis
To Discuss the Areas of Arsenicosis in BD
To Detect the Causes of Arsenicosis in BD
To Discuss the Impacts of Arsenicosis in BD
To Discuss the Mitigation Process of Arsenicosis
in BD
Presented by
Abul Kalam Azad
Senior Lecturer, GED
Northern University Bangladesh
E-mail: [email protected]
Introduction
Arsenic contamination of ground water has
become a catastrophe in Bangladesh. It has
caused enormous health hazards and social
problems. Tube well, which became
unavoidable source of drinking water, is
now a branded evil thing and brings the
poison with ground water. Even, scholars
have begun to say that water should be
redefined as human threat rather than life
giver. Let’s, first of all, define arsenic
contamination and then discuss the causes
and effects of arsenic contamination in
ground water of Bangladesh.
Definition of Arsenic
Arsenic was first written about by Albertus Magnus
(Germany) in 1250.
Qumrul Islam Chowdhury defined arsenic as “a
white semi-metalic powder found in nature.”
[Bangladesh State of Environment Report: Water
and Environment, 1999: 26]
DFID defined arsenic as ~ “both toxic and
carcinogenic” (a substance which causes cancer).
[Groundwater Studies for Arsenic Contamination in
Bangladesh, 1997:1]
Rashida & Mridha defined arsenic as~ “a naturally
occurring poisonous chemical element and always
present as compound.” [Ibid, p- 162]
Arsenic in Nature
1. Arsenic is present in air, soil and water
2. Industrial wastes may emit arsenic to the
atmosphere.
3. Most fruits, vegetables, meats and fishes
contain arsenic
4. Arsenic level in sea water and sea fishes is
higher
5. Human beings take a little amount of arsenic
every day through breaths, food or drinks.
6. An intake of 150 microgram of arsenic per day
should not cause any harmful effect to human
being
7. Very sensitive person becomes sick with as
low as 20 microgram of arsenic a day.
Table: Amount of Arsenic in Different Things
Different Things
Rock Per KG
Soil Per KG
natural water per L
Sea fish per kg weight
Extent of Arsenic
1.5 - 2.0 mg
up to 500 mg
1-2 microgram
5 mg
Chemical Nature of Arsenic at a Glance
Formula
Atomic Number
Atomic weight
Density at 32 degree
Fahrenheit
Melting point
Boiling Point
As
33
74.9216
5.73
1139 degree
Fahrenheit
1497.2 degree
Fahrenheit
Confirmation of Diagnosis
 Detection of arsenic in urine, nail, hair,
skin-scale and liver tissues confirms
diagnosis.
 Normal values: Urine- 0.005-0.04 mg/L.
(level exceeding 1.0 mg/L confirms presence
of excess arsenic); Hair- 0.08-0.25 mg/kg;
Nail- 0.43-1.08 mg/kg.
 Other investigations: Liver function tests,
kidney function tests, endoscopy, routine
examination of blood and urine.
Discovering Arsenic Problem
First sample of arsenic in tube well water was
detected in 1993 in some southern districts of BD.
Arsenic contamination has been found in 19.4%
samples. Acceptable range of arsenic have been
found in tube well water of 155 Thanas of 44
districts (See the table below).
Quest
Answer
Year
Where
Detector
1993
Southern districts of BD
Public Health Eng. Dept of
BD Govt.
% of Sample
Acceptable range of
arsenic found in
19.4 %
155 Thanas of 44 districts
No. of
Affec.
Dist.
More Contaminated Dist.
33
No. of
Affec.
Thana
137
Name of the District
Nawabganj, Bagerhat, Satkhira,
Meherpur, Kushtia, Chuadanga,
Zhinaidah, Magura, Norail,
Jessore, Faridpur, Rajbari,
Gopalganj, Madaripur, Shariatpur,
Laxmipur, Noakhali, Feni,
Chandpur, Comilla, Brahminbaria,
Narayanganj, Pabna, Rajshahi,
Khulna, Munshiganj, Manikganj,
Norshingdi, Sylhet, Sunamganj,
Moulavibazar, Barisal, Pirojpur
No. of
Affec.
Dist.
Less
Contam.
Dist.
11
Contam.
Free
Districts
16
Dist. not
yet
surveyed
4
Total
64
No. of
Affec.
Thana
18
Name of the District
Gaibandha, Kurigram, Nilphamari,
Sirjaganj, Natore, Jamalpur,
Netrokona, Cox'sbazar,
Kishoreganj, Sherpur, Chittagong
Panchagar, Thakurgaon,
Lalmonirhat, Dinajpur, Rangpur,
Joypurhat, Bogra, Naogaon,
Dhaka, Tangail, Mymensingh,
Hobiganj, Bhola, Zhalokathi,
Patuakhali, Gazipur
Causes of Arsenic Contamination in
Ground Water of BD
Rashida & Mridha state: “ . . There are
several speculations about the source
of arsenic contamination in Bangladesh such as~
1. Wooden
electric
poles
of
Rural
Electrification Board which are treated
with chromate copper arsenate (CCA),
ammoniacal copper arsenate (ACA), and
ammoniacal copper zinc arsenic (ACZA);
2. High use of fertilizers and pesticides,
particularly phosphate fertilizers;
3. Role of microbes in the aquifers;
4. Reduction of iron oxyhydroxides etc.
[Ibid, p- 163]
They further state that all these
speculations were gradually rejected
and ultimately a survey shows that
only the shallow and tube-well water
contained
high
concentration
of
arsenic which are usually restricted at
40- 150 feet depth.
Saumyen Guha says: “The source of arsenic
in any aquifer may be either anthropogenic
or natural. Anthropogenic emissions of
arsenic arise from:
Mining ; Fuel consumption ; Smelting of ores (rock or
soil from which metal can be obtained); and the use
of arsenic in fertilizers and pesticides. [A Study of
Arsenic in Drinking Water, Vol # 4, 2001: 1]
According to Miller: Arsenic arises from:
Oxygen- demanding wastes; Disease-causing
agents; Inorganic chemicals; Plant nutrients;
Sediments; Radioactive substances; and
Heat. [Living Environment, p- 357]
Effects of Arsenic on Health
Any form of arsenic compound is toxic to
human. Its toxicity is more than four times
higher than that of the toxic trace element
mercury. The toxic
effect of arsenic
species depend mainly on their chemical
form, route of entry, age, sex, dozes and
duration of exposure. Arsenic toxicity
occurs through contaminated food and
drinking water. Skin diseases are the
common effects of arsenic poisoning. Long
term exposure to excessive arsenic causes
changes in skin pigments and hyperkeratosis;
promotes development of ulcerations of skin,
bladder, kidney and skin.
Table: Arsenic Toxicity in different Organ Systems
Organ
System
Skin
Liver
Nervous
System
Respiratory
System
Endocrine
System
Problems
Symmetric hyperkeratosis
(Figure-1: See below) of palms
melanosis (Figure-2: See below)
or depigmentation, tumour
Enlargement, Jaundice,
hearing loss
Lung Cancer
Diabetes
Figure-1: Hyperkeratosis on the palm
of hand of a young adult
Figure-2: Melanosis on the neck and
chest of a middle aged female
Table- Clinical Feature of Arsenicosis as
observed in Bangladesh
Preclinical
Stage
No preclinical
manifestation
Initial
Stage
Second Stage
Last Stage
Melanosis,
Nephropathy
Depigmenkeratosis,
,
tation,
conjunchepatopathy,
hyperkeratosis
tivitis,
gangrene,
, peripheral
bronchitis,
cancer of
nephropathy,
gastroenter
skin, bladder
hepatopathy
itis
and lung
In Bangladesh, majority of patients are in initial
and second stages
Mitigation of Arsenic Contamination
There is no single magic bullet solution of
arsenic problems. However, many scholars
have given some suggestions.
DFID –suggestions
1. Use of surface water with treatment by
pond sand filter;
2. Sinking deep wells into the arsenic free
aquifers;
3. Rain water harvesting;
4. Sterilization of existing ground water;
and
5. Arsenic treatment at various scales.”
20 Recommendations of the WHO
Immediate
• Identify arsenicoses patients and at
risk patients.
• Provide treatment and nutritious food to
the patients.
• Provide equipment and medicines at
health centers to ensure the treatment.
• Set up regional facilities for detection
of arsenic in water and human body in
collaboration of donor agencies.
• Create alternate source of safe drinking
water.
• Provide training to health personnel and
staff for improving knowledge and
efficiency
in
the
diagnosis
and
management of arsenicoses.
• Enhance awareness of people through
massive health education campaigns.
• Conduct integrated and intensive surveys
in Bangladesh and in West Bengal by the
support of donor agencies.
Long Term
• Establish national database on arsenic problem.
• Examine efficacies of different de-arsination
methods.
• Design local projects suitable for specific
problem prone areas.
• Assess types of training need.
• Build organizational structure to check drinking
water quality.
• Build organizational structure to follow up
arsenicoses patients on regular basis.
• Build National Reference Laboratory for the
detection and evaluation of arsenic presence in
drinking water and human body.
• Provide support to research program relating to
arsenic contamination and reduction of risks.
• Assess need of fund.
• Establish bilateral collaboration with the
Government of India in exchanging experiences,
travels and joint initiatives.
• Strengthen International collaboration for the
solution of the problem.
Conclusion
Finally, it may be said that arsenic
contamination in Bangladesh is a
great health risk, no doubt. So, we
should take proper steps to mitigate
such dangerous poison as early as
possible.