NORTHERN CARIBBEAN UNIVERSITY
DEPARTMENT OF BIOLOGY, CHEMISTRY AND
ENVIRONMENTAL SCIENCES
ECOTOXICOLOGY
ECO-TOXILOGICAL ANALYSIS OF LEAD POISONING IN JAMAICA
SUBMITTED BY:
LATRICIA FRANCIS
LENROY GREEN
ANTONIQUE WILLIAMS 18100441
LESLEY ANN JAMES
Executive Summary
For several decades Jamaican children have been exposed to lead, mainly from mine
waste in the Kintyre region, lead recovery mainly located in the Red Pond area of Spanish Town
and scattered illegal backyard smelting operations mainly in Kingston, St Andrew and St
Catherine. There is also leaded gasoline wherever cars are operated and lead-containing
household paints which are sources of lead contamination. Lead exposure has been associated
with numerous maladies including cognitive and behavioural deficits, hypertension,
osteoporosis, and a range of non-specific constitutional symptoms. Lead is also a potent
neurotoxin especially detrimental to the developing nervous system of the foetus, babies and
young children. The consequence of lead contamination are; social and financial burdens,
reduced intelligence and violent behaviour place demands on society that are far from trivial and
are quite unnecessary since lead poisoning is an entirely preventable malady. This makes the
project a necessary one and bring attention to an issue that has not been given due attention by
the authorities.
This project adds to previous work done on Lead decomposition, contamination and
poisoning in Jamaica and mainly the communities of Mona common, Kintyre and Red pond in St
Catherine. Lead contamination is looked at from an environmental, health, toxic and
psychological perspectives. The chemical structure of lead and its toxicity will be fully explored.
We will further decipher the chemical structure of lead and determine its reactions and
combinations with other substances that enable it to be so toxic. The causes of Lead Deposition
and Poisoning in Jamaica will be explored at different locations as we generally investigate the
locations of lead poisoning have occurred. Two locations namely Red Pond St Catherine and
Mona Commons St. Andrew will looked at for an in-depth comparative analysis. Current
mitigation policies that have been implemented by the government will also be identified while
possible ones that could be implemented will be provided.
The information gathered and analysed has proven that Lead exposure has been
associated with numerous maladies including cognitive and behavioural deficits, hypertension,
osteoporosis, and a range of non-specific constitutional symptoms. Lead is also a potent
neurotoxin especially detrimental to the developing nervous system of the foetus, babies and
young children. There has been an increased appreciation in Jamaica of the dangers associated
with lead deposition, however; backyard lead smelting is still being carried out. As such, there
remain a substantial number of chronically lead poisoned children who require suitable clinical
and environmental interventions. This is becoming better understood and there are increased
efforts to manage lead pollution in the Jamaican environment. Medical and environmental
interventions is needed to produce significant reductions in blood lead levels and such
interventions if they are going to be effective they will require longer term monitoring and
support.
Acknowledgments
This work was supported by the Northern Caribbean University Department of Biology
Chemistry and Environmental Sciences. Acknowledgements are also made to the staff of that
department who eagerly cooperated and shared ideas and knowledge on the topic. Dr. Vincent
Wright Dean of the College of Natural and Applied Sciences, Dr. Mark Harris, Geochemist and
Associate Professor Northern Caribbean University. The University of the West Indies, Ms
Kameaka Duncan, and Ms Pansy Matthews, principal of the Mona Commons Basic School.
Table of Contents
Title
Page
Goals and Objectives...............................................................................................................1
Section A
Introduction.............................................................................................................................2
Environmental Impact of Lead Poisoning...............................................................................3
Health Impact of Lead Poisoning.............................................................................................6
Toxic Impact of Lead Poisoning..............................................................................................8
Psychological Impact of Lead Poisoning................................................................................8
Section B
Chemical Structure of Lead.....................................................................................................11
Reaction of Lead with other chemicals...................................................................................14
Section C
Description Study Areas for Lead Poisoning…………………………………………………17
Toxic Killing………………………………………………………………………………….24
Discussion on the causes of Lead Deposition and Poisoning in Different Parts of Jamaica...25
Section D
Mitigations against Lead Toxicity in Jamaica........................................................................29
Conclusions and Recommendations......................................................................................, 34
References..............................................................................................................................36
List of Tables
Title
Pages
Table1- Showing the chemical properties of lead...................................................12
Table 2 - Blood lead levels results for a total of 107 children
from the Mona Commons.......................................................................................18
Table 3 – Summary of chelated children’s blood level over 3 months period........19
Table 4 – Variation of blood level (mg/dL) with time after discharge...................20
Table 5 – Lead contents of environmental samples in Mona Commons................21
List of Figures
Title
Pages
Figure 1 – X-ray images showing lead in bone of lead poisoned children..................19
Figure 2 – Blood levels of the emergency cases before and after chelation
Therapy treatment..........................................................................................................21
Figure 3 – Contaminating effect of the lead smelting operation in Mona Commons
Illustrated by the concentration distribution of lead in the soils...................................22
List of Plates
Title
Page
Lead Poisoning.................................................................................................7
Toxic Killing...................................................................................................24
Goals and Objectives
The goals of this project are to study the impact of Lead Poisoning in Jamaica. We will
accomplish this by looking at the impacts from an environmental, health, toxic and psychological
perspectives. We will further decipher the chemical structure of lead and determine its reactions
and combinations with other substances that enable it to be so toxic. The causes of Lead
Deposition and Poisoning in Jamaica will be explored at different locations as we generally
investigate the locations of lead poisoning have occurred. Finally two locations namely Red
Pond St Catherine and Mona Commons (Kintyre) St. Andrew will looked at for an in-depth
comparative analysis.
Other general objectives include:
 To define lead poisoning.
 To identify the sources of lead poisoning.
 To determine the signs and symptoms of lead poisoning in children.
 To determine the effects and complications associated with lead poisoning.
 To identify current mitigation policies that have been implemented by the government
while providing possible ones that could be implemented.
 To assess all the impact lead poisoning has on Jamaica
1
Introduction
For several decades Jamaican children have been exposed to lead, mainly from mine
waste in the Kintyre region, lead recovery mainly located in the Red Pond area of Spanish Town
and scattered illegal backyard smelting operations mainly in Kingston, St Andrew and St
Catherine. There is also leaded gasoline wherever cars are operated and lead-containing
household paints which are sources of lead contamination. One of the greatest concerns
associated with lead contamination is the lag period; this refers to the time the lead takes to get
out of the environment. In any event, the potential damage of lead seems to increase with each
discovery made, so for the future, lead exposure for children should be kept to an absolute
minimum and those previously affected require continuing medical attention for a long time.
Although lead contamination and poisoning continues to be an issue of concern, much
progress has been made in restricting the amount of lead in the Jamaican environment: The
sources of poisoning in the Kintyre and other areas have been isolated, the lead recovery plant
closed, backyard smelting has been greatly reduced, lead in household paint discontinued.
Leaded gasoline was banned by the Government in 2000, and toy imports are checked for toxic
levels. But the continuing warnings provided by worldwide studies on lead toxicity should
maintain a sense of urgency in protecting our children. And it should be remembered that the
greatest risk of lead poisoning in Jamaica is now the improper disposal of lead-acid batteries
The impacts of lead poisoning can be categorized as follows: Environmental, Health, Toxic and
Psychological. These will be looked at in details.
2
Environmental Impact of Lead Poisoning
Lead contamination within the environment does not only caused by leaded gasoline. Other
human activities, such as fuel combustion, industrial processes, mining, and solid waste
combustion also contribute to concentrations of lead within the environment. Lead can end up in
water and soils through corrosion of leaded pipelines in a water transporting system and through
corrosion of leaded paints. It cannot be broken down; it can only be converted to other forms.
Lead accumulates in the bodies of water organisms and soil organisms. In the areas of study, Red
Pond in St. Catherine is the accumulation of lead in water and Kintyre in St. Andrew the lead
accumulation is in the soil. The contamination of the atmosphere, the water and the soil will lead
to environmental degradation.
Air: Lead particles are emitted from automobiles to the atmosphere as lead halides (e.g., PbBrCl)
and as the double salts with ammonium halides (e.g., 2PbBrCl NH4Cl); lead particles are emitted
from mines and smelters primarily in the form of PbSO4, PbO.PbSO4, and PbS (EPA, 1986). In
the atmosphere, lead exists primarily in the form of PbSO4 and PbCO3 (EPA, 1986). How the
chemical composition of lead changes in dispersion is not clear.
Water: Lead has a tendency to form compounds of low solubility with the major anions found in
natural water. In the natural environment, the divalent form (Pb2+) is the stable ionic species of
lead. Hydroxide, carbonate, sulphide, and, more rarely, sulphate may act as solubility controls in
precipitating lead from water. A significant fraction of lead carried by river water is expected to
be in an undissolved form. This can consist of colloidal particles or larger undissolved particles
of lead carbonate, lead oxide, lead hydroxide, or other lead compounds incorporated in other
components of surface particulate matter from runoff. This will block the sunlight from
3
penetrating the water bodies thus affecting the ecosystem of the water. Not only that but the
water may be used for domestic purposes and thus pose a risk to health.
Soil: Paint is a major contributor to soil lead contamination. Remediation of exterior lead-based
paint hazards is critical if further contamination is to be avoided. The accumulation of lead in
soil is primarily a function of the rate of deposition from the atmosphere. The fate of lead in soil
is affected by the specific or exchange adsorption at mineral interfaces, the precipitation of
sparingly soluble solid phases, and the formation of relatively stable organo-metal complexes or
chelates with the organic matter in soil.
Evidence exists that atmospheric lead enters the soil as lead sulphate or is converted rapidly to
lead sulphate at the soil surface. Lead sulphate is relatively soluble, and thus could leach through
the soil if it were not transformed. In soils with pH of > or = 5 and with at least 5% organic
matter, atmospheric lead is retained in the upper 2-5 cm of undisturbed soil.
Lead may mobilize from soil when lead-bearing soil particles run off to surface waters during
heavy rains. Lead may also mobilize from soil to atmosphere by downwind transport of smaller
lead- containing soil particles entrained in the prevailing wind. This latter process may be
important in contributing to the atmospheric burden of lead around some lead-smelting and
Superfund sites that contain elevated levels of lead in soil.
The downward movement of lead from soil by leaching is very slow under most natural
conditions. The conditions that induce leaching are the presence of lead in soil at concentrations
that either approach or exceed the sorption capacity of the soil, the presence in the soil of
materials that are capable of forming soluble chelates with lead, and a decrease in the pH of the
4
leaching solution (e.g., acid rain). Partial favourable conditions for leaching may be present in
some soils near lead- smelting sites that contain elevated levels of lead in soil. A typical example
how leaching has led to water contamination that posed a health threat to persons who come in
contact with this contaminated water is the Red Pond community in St. Catherine.
When the environment is contaminated with lead then the ecosystem is affected. Lead
contamination affect the health on shellfish, this happens when very small concentrations of lead
are present. Body functions of phytoplankton can be disturbed when lead interferes.
Phytoplankton is an important source of oxygen production in seas and many larger sea-animals
eat it. That is why we now begin to wonder whether lead pollution can influence global balances.
Soil functions are disturbed by lead intervention, especially near highways and farmlands, where
extreme concentrations may be present. Soil organisms than suffer from lead poisoning, too.
Lead is a particularly dangerous chemical, as it can accumulate in individual organisms, but also
in entire food chains.
5
Health Impact of Lead Poisoning
Lead is a heavy metal that enters the body via inhalation or ingestion, which usually makes
children more susceptible to poisoning since they may spend more time outdoors and may
consume food not properly washed. Extensive studies conducted on the heavy metal revealed
that it is possible that every part of the body might be affected by lead. It competes with metals
that are essential for bodily function, such as calcium, but it has no biological value. Lead plays
no essential role in the body. Lead can enter the human body through uptake of food, water and
air. Foods such as fruit, vegetables and grains. This may be a result of contaminated soil. The
lead then moved from the soil to the plant and so the food is contaminated. Seafood may contain
significant amounts of lead due to the presence of lead in water; aquatic organism may take in
lead and thus results in the seafood contamination. Cigarette smoke also contains small amounts
of lead.
Lead can enter (drinking) water through corrosion of pipes. This is more likely to happen when
the water is slightly acidic. Lead can cause several unwanted effects on health such as:
- Disruption of the biosynthesis of haemoglobin and anaemia
- A rise in blood pressure
- Kidney damage
- Miscarriages and subtle abortions
- Disruption of nervous systems
- Brain damage
- Declined fertility of men through sperm damage
- Diminished learning abilities of children
- Behavioural disruptions of children, such as aggression, impulsive behavior and hyperactivity
6
Lead can enter a foetus through the placenta of the mother. Because of this it can cause serious
damage to the nervous system and the brains of unborn children. The diagram below summarizes
the impact of lead poisoning on the body:
7
Toxic Impact of Lead Poisoning
Lead is cancer-causing, and adversely effects reproduction, liver and thyroid function, and
disease resistance. The main potential ecological impacts of wetland contaminants result from
direct exposure of algae, benthic invertebrates, and embryos and fingerlings of freshwater fish
and amphibians to lead. It can be bioconcentrated from water, but does not bioaccumulate and
tends to decrease with increasing trophic levels in freshwater habitats. Lead adversely affects
algae, invertebrates, and fish. There are also limited adverse effects in amphibians, including loss
of sodium, reduced learning capability, and developmental problems. Fish exposed to high levels
of lead exhibit a wide-range of effects including muscular and neurological degeneration and
destruction, growth inhibition, mortality, reproductive problems, and paralysis. Lead adversely
affects invertebrate reproduction; algal growth is affected. Lead partitions primarily to
sediments, but becomes more bioavailable under low pH, hardness and organic matter content.
Lead bioaccumulates in algae, macrophytes and benthic organisms, but the inorganic forms of
lead do not biomagnify.
At elevated levels in plants, lead can cause reduced growth, photosynthesis, mitosis, and water
absorption. Birds and mammals suffer effects from lead poisoning such as damage to the nervous
system, kidneys, liver, sterility, growth inhibition, developmental retardation, and detrimental
effects in blood. Lead poisoning in higher organisms has been associated with lead shot and
organo-lead compounds, but not with food chain exposure to inorganic lead. There are complex
interactions with other contaminants and diet. Lead poisoning also affects neurologic processes.
At very high blood lead levels, lead is a powerful abortifacient. At lower levels, it has been
associated with miscarriages and low birth weights of infants. Predominantly to protect the
developing foetus.
8
Psychological Impact of Lead Poisoning
The development of the brain involves two different but interrelated organizational periods. ‘The
first period begins at conception and includes the major histogenetic events, such as neurulation,
proliferation, migration and differentiation. It has been proposed that these events may be
controlled by genetic and epigenetic events, which give rise to neural structures that are
amenable to external influence. The second period is a time of reorganization in the human
cortex. These events occur during gestation and continue postnatally, possibly through the
second decade of life. This stage is characterized by dendritic and axonal growth, synapse
production, neuronal and synaptic pruning, and changes in neurotransmitter sensitivity’. Synaptic
pruning, the process by which the rich overproduction of synaptic connections that characterizes
early development is shaped by experience and learning‐dependent synaptic activity to eliminate
redundant connections, also seems to be particularly sensitive to lead’s effects.
The architecture of cortical processing units is also affected by lead’s developmental influences.
The effects of lead on the development of the nervous system establish the basis for cognitive
impairments in lead‐exposed children, while specific effects on glutamatergic transmission,
which is critically involved in both development and neuronal plasticity, presage impairments in
learning and memory. Disruption of dopaminergic functioning, which is normally involved in
not only motor control but also attention, memory and executive functioning, can produce a host
of behavioural problems, including attention deficit hyperactivity disorder, as well as cognitive
impairments. Based on these impairments to the central nervous system then the psychological
aspect of the individual will be affected. There is a great possibility that persons who are exposed
to lead contamination are more likely to be aggressive and out of order, due to the central
nervous system impairment caused by the exposure to lead.
9
Although lead exposure is associated with increases in problematic behaviour, it is not clear if
the observed behaviours are caused directly by lead‐induced brain damage or are secondary to
the handicaps imposed by cognitive impairments. Brain‐injured children frequently experience a
loss of confidence in response to the academic difficulties they experience due to cognitive
deficiencies. Repeated reminders of one’s inadequacies in comparison with peers—nowhere is
this more likely than in a classroom where testing allows letter‐grade ranking of abilities—
ultimately often causes loss of self‐esteem and poor social development. However, lead also
affects the brain systems that regulate social/emotional functioning.
Christine Forrester-Gill, a health professional, has argued that the high crime rate in Jamaica has
for too long been erroneously blamed on many social factors. Drawing on research carried out by
Dr Herbert Needleman, a medical pioneer in the United States, Dr Forrester-Gill says the
exposure to lead may be one of the most significant causes of violent crime in young people. "It
is clear that a lead contamination problem exists in pockets of Jamaica. But how research
correlating lead poisoning to impulsivity, violence, homicide and criminality applies to Jamaica.
10
Chemical Structure of Lead
Anglesite (PbSO4), cerussite (PbCO3), and minim (Pb3O4) are other common lead minerals.
Lead is a bluish-white metal of bright luster, is very soft, highly malleable, ductile, and a poor
conductor of electricity. It is very resistant to corrosion. It is used in containers for corrosive
liquids (such as sulphuric acid) and may be toughened by the addition of a small percentage of
antimony or other metals. Natural lead is a mixture of four stable isotopes: lead-204 (1.4%),
lead-206 (24.1%), lead-207 (22.1%), and lead-208 (52.4%). Lead isotopes are the end products
of each of the three series of naturally occurring radioactive elements: lead-206 for the uranium
series, lead-207 for the actinium series, and lead-208 for the thorium series. Forty other isotopes
of lead, all of which are radioactive, are recognized. Its alloys include solder, type metal, and
various antifriction metals. Great quantities of lead, both as the metal and as the dioxide, are used
in storage batteries. Much metal also goes into cable covering, plumbing, ammunition, and in the
manufacture of lead tetraethyl. The metal is very effective as a sound absorber, is used as a
radiation shield around X-ray equipment and nuclear reactors, and is used to absorb vibration.
White lead, the basic carbonate, sublimed white lead (PbSO4) chrome yellow (PbCrO4), red lead
(Pb3O4), and other lead compounds are used extensively in paints, although in recent years the
use of lead in paints has been drastically curtailed to eliminate or reduce health hazards. Lead
oxide is used in producing fine “crystal glass” and “flint glass” of a high index of refraction for
achromatic lenses. The nitrate and the acetate are soluble salts. Lead salts such as lead arsenate
have been used as insecticides, but their use in recent years has been practically eliminated in
favour of less harmful organic compounds. Care must be used in handling lead as it is a
cumulative poison. Environmental concern with lead poisoning has resulted in a national
program to eliminate the lead in gasoline.
11
Table1 showing the chemical properties of lead:
Atomic number
82
Atomic mass
207.2 g.mol -1
Electronegativity according to
1.8
Pauling
Density
11.34 g.cm-3 at 20°C
Melting point
327 °C
Boiling point
1755 °C
Vander Waals radius
0.154 nm
Ionic radius
0.132 nm (+2) ; 0.084 nm (+4)
Isotopes
13
12
Electronic shell
[ Xe ] 4f14 5d10 6s2 6p2
Energy of first ionisation
715.4 kJ.mol -1
13
Reaction of lead with other chemicals
 Reaction of lead with air
The surface of metallic lead is protected by a thin layer of lead oxide (PbO). Only upon heating
lead to 600-800°C does lead react with oxygen in air to from lead oxide, PbO. The reaction can
be represented by the equation: 2Pb(s) + O2(g) → 2PbO(s)
 Reaction of lead with water
The surface of metallic lead is protected by a thin layer of lead oxide, PbO. It does not react with
water under normal conditions.
 Reaction of lead with halogens
Lead metal reacts vigorously with fluorine, F2, at room temperature and chlorine, Cl2, on
warming to form the poisonous di-halides lead (II) fluoride, PbF2, and lead (II) chloride, PbCl2,
respectively. This reaction can be represented as follows:
Pb(s) + F2(g) → PbF2 (s)
Pb(s) + Cl2(g) → PbCl2(s)
 Reaction of lead with bases
Lead dissolves slowly in cold alkalis to form plumbites.
 Reaction of lead with acids
14
The surface of metallic lead is protected by a thin layer of lead oxide, PbO. This renders the lead
essentially insoluble in sulphuric acid, and so, in the past, a useful container of this acid. Lead
reacts slowly with hydrochloric acid and nitric acid, HNO3. In the latter case, nitrogen oxides are
formed together with lead (II) nitrate, Pb (NO3)2.
Lead(II,IV) oxide
Lead (II, IV) oxide, also called minimum, red lead or triplumbic tetroxide, is a bright red or
orange crystalline or amorphous pigment. Chemically, red lead is Pb3O4, or 2 PbO·PbO2. Lead
(II, IV) oxide is used in the manufacture of batteries, lead glass and rust-proof primer paints.
Red lead is virtually insoluble in water and in alcohol. However, it is soluble in hydrochloric acid
present in the stomach, and is therefore toxic when ingested. It also dissolves in glacial acetic
acid and a diluted mixture of nitric acid and hydrogen peroxide.
Lead tetra oxide is most often used as a pigment for primer paints for iron objects. Due to its
toxicity, its use is being limited. In the past, it was used in combination with linseed oil as a
thick, long-lasting anti-corrosive paint. The combination of minimum and linen fibres was also
used for plumbing, now replaced with PTFE tape. Currently it is mostly used for manufacture of
glass, especially lead glass. It finds limited use in some amateur pyrotechnics as a relatively
potent oxidizer. Red lead is used as a curing agent in some polychloroprene rubber compounds.
It is used in place of magnesium oxide to provide better water resistance properties. Red lead was
also used for engineer's scraping, before being supplanted by Engineer's blue. In traditional
Chinese medicine, red lead is used to treat ringworms and ulcerations, though the practice is
limited due to its toxicity. Also, azarcon, a Mexican folk remedy for gastrointestinal disorders
contains up to 95% lead (II, IV) oxide.
15
When inhaled, lead (II, IV) oxide irritates lungs. In case of high dose, the victim experiences a
metallic taste, chest pain, and abdominal pain. When ingested, it is dissolved in the gastric acid
and absorbed, leading to lead poisoning. High concentrations can be absorbed through skin as
well, and it is important to follow safety precautions when working with lead-based paint. Longterm contact with lead (II, IV) oxide may lead to accumulation of lead compounds in organisms,
with development of symptoms of acute lead poisoning. Chronic poisoning displays as agitation,
irritability, vision disorders, hypertension, and also a greyish facial hue.
Lead (II, IV) oxide was shown to be carcinogenic for laboratory animals. Its carcinogenicity for
humans was not fully proven, however; it is still believed to be the most toxic and the most
dangerous oxide or form of lead to humans.
.
16
Description Study Areas for Lead Poisoning
Lead exposure has been associated with numerous maladies including cognitive and
behavioural deficits, hypertension, osteoporosis, and a range of non-specific constitutional
symptoms. Lead is also a potent neurotoxin especially detrimental to the developing nervous
system of the foetus, babies and young children. Most children with elevated blood lead levels
are asymptomatic, but irreversible damage to the developing brain leads to a lowering of IQ and
there are substantial statistical correlations between behavioural problems and the consumption
of leaded gasoline over years. The risk of lead poisoning is especially high for children in poorer
circumstances since exposure is also likely to be higher and accompanied by iron and calcium
deficiencies that result in higher blood lead concentrations. The two areas that are concentrated
on for this lead poisoning report are:
Red Pond in St. Catherine
Mona Commons in St. Andrew
17
Results for a survey done at Mona Commons which includes Kintyre:
Blood lead levels results for a total of 107 children from the Mona Commons are summarized in
Table 2.
As many as 59% of these children showed BPb levels above the CDC intervention level of >10
µg/dL and the population mean is unacceptably high. Of these, 48 children received iron
supplements; eight with BPb levels between 40 and 60 mg/dL were referred to the paediatric
outpatient clinic at the University Hospital of the West Indies. One child continued to visit the
clinic for over a year and received oral chelation with succimer, with an overall decline in the
BPb level of only 9%.
The five children with the highest BPb values (ranging from 89 µg/dL to 202 µg/dL), well above
the present CDC emergency level of 70 µg/dL, were admitted to the UHWI. Two presented with
lead encephalopathy; one of these (BPb = 126 µg/dL) went on to have status epileptics, which is
common in children with BPb above 100 µg/dL but has also been seen at levels of about 70
µg/dL (11). These children required acute seizure management prior to the initiation of chelation
therapy. The severe chronic exposure of these children to lead was the result of backyard lead
smelting ex-acerbated by significant pica and chronic nutritional anaemia. The radiograph shown
as Fig. 1, of (A) upper limbs and (B) lower limbs of one of these children illustrates a marked
18
linear increase in the density of the metaphytes, attributed to the significant lead uptake that had
already occurred in the bones.
Chelation Therapy
A summary of the BPbs on chelation during hospitalization is shown in Table 3.
The variations of BPb levels of the five children after chelation during hospitalization are shown
in Fig. 2.
19
Overall, the time variation patterns of BPb were similar in each child. After the first chelation,
the levels fell by 46–76% and initially tended to increase between chelation (12). Twenty-one
days after the third chelation the BPb levels were 13–28 µg/dL at which time the children were
discharged from hospital. During the following weeks, there were significant increases in BPb
shown in Table 4.
On discharge, the children were placed in a government home for the care of children where they
20
were monitored. Oral chelation treatment was provided with succimer for those whose BPb level
had risen above 50 µg/dL. After the last chelation treatment, the children were returned by the
parents to the original residence. Further follow-up was indicated.
Environmental evaluations
Some environmental assessment results for Mona Commons are summarized in Table 5.
The soil samples at the home of the lead-poisoned children and the immediate surroundings
showed levels as high as 30 000 mg/kg. The range of soil lead concentrations in Canada and
many European countries in 25 – 100 mg/kg (13). The lead concentration in uncontaminated
Jamaican soils is 44 mg/kg (14). The dust sample collected from the floor of the children’s home
showed lead concentration of 373 µg/f2, nearly ten times in excess of the United States
Environmental Protection Agency PA limit of 40 µg/f2. The lead content of the drinking water
was below the sensitive detection limits of atomic absorption spectroscopy and that of all
Jamaican foods so far examined is also low (15). The contaminating effect of the lead smelting
operation in Mona Commons is illustrated in Fig. 3 by the concentration distribution of lead in
the soils.
21
The extent of lead contamination is obvious; some 50% of the soil area had lead soil
concentrations greater than 400 mg/kg, the US EPA lead limit for residential soils (16). The area
near to the smelting operation, including the five lead-poisoned children’s yard, was grossly
contaminated, and despite the high density of lead and its compounds, even at 30 feet above
ground level there were quite significant concentrations in the outdoor dust.
Results for a survey done at Red Pond, St. Catherine
In a report published in 2002 by the International Centre for Nuclear Sciences (ICENS) at the
University of the West Indies a comprehensive analysis was done on the Red Pond community in
Spanish Town St Catherine after Professor Lalor had identified alarming levels of lead in the
area and it was once again brought to national attention when a number of school children were
diagnosed with lead poisoning. For their research the (ICENS) reported that approximately 300
children at basic schools were screened for blood lead to identify risk areas for further
22
examination. The response and cooperation of parents, teachers and children was excellent. The
‘hot-spot’ areas where mapping and analysis of survey samples by ICENS indicated highest risk
were examined in detail to identify possible sources of lead exposure, e.g. soil, dust, water, food,
and cooking utensils. A community-based intervention programme was developed (including
education of the public, the parents, teachers, and children on how to minimize exposure to lead)
and targeted at the population at risk. The study results provided a database which will be used
for future monitoring of blood lead levels of Jamaican children.
The range of blood lead levels observed for children In Spanish Town was very large and eighty
children (80) were given medical attention, several receiving repetitions of chelation therapy
over periods of time. This represented a 26.7% of the total number of children tested in and
around Red Pond and the general Spanish Town area. In later life, high levels of chronic
exposure to lead can contribute to seizures, reduced intelligence, lower productivity and aberrant,
sometimes violent behaviour that place social and financial burdens on society. The higher
blood lead values were found mainly in the Kingston and St. Andrew Corporate area and in St.
Catherine. It was possible to reduce most of the high levels by isolation of the contamination
from the environment, education, and improved nutrition and hygiene, although there remain
some intermediate values which should receive attention.
The main source of exposure to lead in St Catherine was identified as the contamination caused
by backyard recycling of used lead-acid batteries. The smelter-contaminated soils so far
identified are mainly in St. Catherine and in the Corporate area; some smelters have also been
observed on fishing beaches. Other potential sources exist, most of which are already regulated
by the government: the sale of leaded gasoline for automobiles, leaded paints, and toys, trinkets
23
etc. that contain lead are banned. Food and water appear to contribute little to population
exposure. Professor Lalor said more than 60 children from that community were exposed and
had to be treated for lead poisoning. He says adults from Red Pond in St Catherine are still
suffering from the effects of lead poisoning. Professor Lalor explains that ICENS is not a public
health group and does not have adequate human resources to do checks across the country for
lead. The ICENS head is hoping the Ministry of Health will carry out this exercise.
Toxic killing
An order by the local council warning of lead-contaminated areas in Red Pond, St Catherine, is
seen in this 2004 Gleaner file photo. - photos by Andrew Smith/Photography Editor ( Jamaica
Gleaner Archive).
24
Discussion on the causes of Lead Deposition and Poisoning in Different Parts of Jamaica
Lead poisoning is not new to Jamaica. This hazardous material has affected hundreds of children
in communities such as Kintyre, Mona Commons, Marverly in St Andrew, Red Pond in St
Catherine and other locations in Kingston and St Catherine where illegal smelting operations are
flourishing. These communities have been plagued by incidents of violence over many years.
The continuous accumulation of lead in an environment may be caused by varying factors.
However the cause may be lead deposition is a detrimental activity since it will lead to poisoning
and as a result, lead deposition should be prevented in every way possible.
In 2001, the Jamaican law stipulated that the manufacture of lead in materials such as
paint and gasoline was illegal. However During our research it was seen that the reported
incidents of lead poisoning were seen in the urbanized areas such as red pond community St
Catherine along with the others as was previously mentioned. The causes of lead deposition and
poisoning are different based on location. Places who practice activities that use lead is more
susceptible to lead problems than those areas such as Middle Quarters St Elizabeth where little
or no lead based activity takes place. Based on studies between 1984 and 2000, and even up until
2012, it has been seen where the most exposure to lead is seen in the battery repair shops.
The Red pond community in St Catherine is an area where proliferation of “backyard
battery repair shops” has been a main cause in the lead poisoning rate in the country. The leadcontaminated top soil from the community and other areas of deposition at unknown sites
resulted in high levels of lead poisoning among residents, especially small children.. People at
risk for lead poisoning based on these reports are battery repair workers, workers in the metal
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refining industry, and children and other residents living in close proximity to backyard battery
smelters.
Other sources in the past were lead based paint, leaded gasoline and old water pipes, but
these have all been phased out over time. Uncommon sources include food stored in lead-glazed
pottery, low-quality toys, metal trinkets, and crayons. Toddlers commonly put their hands in
their mouths, suck their thumbs, and explore their environment by tasting things and are at
greater risk for lead poisoning. Even though it is illegal lead-based paint is still on walls and
woodwork in many older homes and apartments. Most lead poisoning in children results from
eating lead-based paint chips. Lead pipes, brass plumbing fixtures and copper pipes soldered
with lead can release lead particles into tap water thus allowing the risk of having lead poisoning
increase.
Lead seldom occurs naturally in water supplies like rivers and lakes. Lead enters drinking
water primarily as a result of the lead deposition by corrosion, or wearing away, of materials
containing lead in the water distribution system and household or building plumbing. These
materials include lead-based solder used to join copper pipe, brass and chrome plated brass
faucets older construction may still have plumbing that has the potential to contribute lead to
drinking water. Lead particles that settle on the soil from leaded gasoline or paint can last for
years. Lead-contaminated soil is still a major problem around highways and in some urban
settings. Household dust can contain lead from lead paint chips or from contaminated soil
brought in from outside. Glazes found on some ceramics, china and porcelain can contain lead
that may leach into food. Kohl is a traditional cosmetic, often used as eyeliner. Testing of various
26
samples of kohl has revealed high levels of lead and the exposure to this lead based equipment is
a frequent experience among women of every age group.
Numerous previous studies have confirmed the extent of lead poisoning worldwide, the
neurotoxicity of lead; it’s lowering of IQ values, the increased risk of severe learning disabilities
and impulsive sometimes violent behaviour, and contributions to increased crime rates in
juveniles and adults. It was after all such work that demonstrated the dangers of chronic lead
exposures and convinced governments to restrict the use of this very important material
ironically the removal of lead from gasoline was first done because it poisoned the catalytic
converters needed to meet new emission controls. This earlier work provided a logical core for
Nevin's and Reyes' analyses of crime rates and lead poisoning.
The United States data show two lead-poisoning spikes: the earlier Nevin links to lead in
household paint which was outlawed in 1978, the later post-World War II, they both attribute to
the great increase in the use of leaded gasoline which was gradually phased out in the US during
the 1970s and '80s. These blood lead and crime incidence data rise and fall together and there is a
very strong association between preschool blood lead and subsequent crime rate trends over
several decades, not only for the US but also for Britain, France, Australia, Finland, Italy, West
Germany and New Zealand, where the decisions on lead removal came somewhat later and other
conditions might reasonably differ. The relationship is characterised by best fit lags (highest R2
and t-value for blood lead), consistent with neurobehavioral damage in the first year of life and
the peak of offending for index crime, burglary and violent crime. The impact of blood lead is
also evident in age-specific arrests and incarceration trends. Regression analysis of average
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1985-1994 murder rates across US cities suggests that murder could be especially associated
with more severe cases of childhood lead poisoning."
These international data helps to confirm what Dr Needleman had concluded in studies
done in AMAICA. Dr. Needleman, a paediatrician, researcher and professor at the University of
Pittsburgh, conducted studies on the neurodevelopmental damage caused by lead poisoning. He
concluded that when environmental lead finds its way into the developing brain, it disturbs
mechanisms responsible for the regulation of impulse. This, according to Needleman, could
ultimately lead to anti-social and criminal behaviour, hence the correlation of high crime levels
in Kingston, Spanish Town and other parts of the cooperate areas where the highest level of BPb
were found.
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Mitigations against Lead Toxicity in Jamaica
Due to its devastating nature as a presence in both the environmental and human population,
steps and measures have been put in place over the years to eradicate, reduce and educate about
the adverse effects lead toxicity poses. There are a myriad of means with which individuals
especially children can be poisoned. These means include:

lead added to gasoline

lead from an active industry, such as mining (especially in soils)

lead-based paints and pigments,

drinking-water systems with lead solder and lead pipes

lead released by incineration of lead-containing waste

lead in electronic waste (e-waste)

lead in the food chain, via contaminated soil
Lead contamination as a legacy of historical contamination from former industrial sites.
Jamaica’s greatest exposure to lead poisoning came through the smelting to lead batteries and
from lead ore mining. In 1963, recovery of lead from used batteries was established in Red Pond
district near Spanish Town. This business became very lucrative and as a result backyard
smelting by other Jamaicans was established. This practice continued into the 1980’s until the
increase in incidences of lead poisoning became highly noticeable. Other incidences during that
period include: lead poisoning of children at the Kintyre Basic School which sits on the land that
used to house a mill which crushed and concentrated lead ore, research done by American
scientists who prove that lead poisoning of pregnant mothers can have implications on criminal
activity of the child when he reaches adulthood and other problems.
29
These issues have led to the development of, and implementations of mitigations which
are responsible for the reduction, eradication and education of lead and its effects on the
environment and the populace. These mitigations have worked effectively for the period that
they were implemented. But as is always the case, as soon as a government demits power or an
activist leaves office, the work declines and comes to a halt. Mitigation for such a situation
involves clean-up and then preventative measures to prevent the event from occurring again. The
following are examples of mitigations that have been implemented over the years and the results
they have garnered:
I.
Ministry of Education and Child Development Centre (1988)
In 1988, The Ministry of Health in collaboration with the Child Development
Centre did extensive research which defined and publicised the scale of the problems
involved in backyard smelting and its resultant effect on children and handlers of the
substance. Measures were taken to close the company, ban smelting, and made the
dangers quite potent and evident to not only the residents of Red Pond but to the wider
island. This mitigation was as effective as it could have been at the time but the major
loophole is that the act of smelting was not completely eradicated. Many illegal backyard
smelting areas continued and so the possibility of contamination still existed.
II.
International Centre for Environmental and Nuclear Science with Environmental
Foundation of Jamaica.
The International Centre for Environmental and Nuclear Science in collaboration
with the Environmental Foundation of Jamaica produced three mitigation products over a
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period of ten (10) years which dealt with eradication, monitoring and education of
individual in areas that were susceptible to lead poisoning.
a. Mitigation of Lead Hazard in the Hope Mine Area ( 1995- 1996)
This mitigation involved mapping the areas that were most contaminated and then
putting measures in place to reduce the movement of dust and soil from the area. This
would limit the amount of contamination to the Hope River and surrounding
communities.
b. Improvement of Community Health in the Hope River Valley through Lead
Abatement (2000-2002)
This mitigation concentrated on the health of the community and isolating the
remaining lead contamination in the area. This was done by testing the food, dust, air,
water, lead and other means of lead contamination. The community became very
involved and after being educated were more aware on measures to take to prevent
contamination
c. Childhood Screening for Lead Poisoning and Lead Mitigation in Jamaica
(2003- 2005).
This mitigation included the testing of the blood of children across
Jamaica in areas that are prone to lead poisoning. These areas included:
Kingston, Montego Bay, Mandeville, Port Antonio and Browns Town and
other rural areas. The plan was to look at the blood levels across Jamaica
and do a comparison. The highest blood levels were found in Kingston
and St. Andrew along with St. Catherine. The children that were tested
and found to have high lead blood levels were given treatment.
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III.
Ministry of Environment (2005)
The Ministry of Environment in 2005, created the National Used Lead Acid
Batteries Project where, batteries were collected from garages, gullies, new and
used car dealerships, communities, designated collection spots and along
roadways. These batteries were to be exported to Trinidad and Tobago for
recycling. This was in an effort to reduce the number of available batteries for
smelting and reduce the risk of lead poisoning.
These are some of the mitigations implemented by Jamaica. There are other mitigations that can
be of significant importance and even assistance in eradicating the incidences of lead toxicity in
Jamaica. These methods include:
A. Development of a sector in the Ministry of Public Health that deals specifically
with the education and monitoring of the health of individuals in areas prone to
lead contamination
B. Programmes where there is a collection and accountability for used batteries,
small owners can sell to larger qualified companies for agreed and reasonable
prices to prevent backyard smelting.
C. Vigorous and continuous education programmes, especially in areas where the
contamination is prevalent or impending.
D. A central agency can be put in place to monitor the activities of other areas
dealing with Lead poisoning education and eradication. This is to prevent a lapse
in the work if there is a change in heads of government or activists.
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Much progress has been made in restricting the amount of lead in the Jamaican
environment: The sources of poisoning in the Kintyre and other areas have been isolated, the
lead recovery plant closed, backyard smelting has been greatly reduced, lead in household paint
discontinued. Leaded gasoline was banned by the Government in 2000, and toy imports are
checked for toxic levels. But the continuing warnings provided by worldwide studies on lead
toxicity should maintain a sense of urgency in protecting our children. And it should be
remembered that the greatest risk of lead poisoning in Jamaica is now the improper disposal of
lead-acid batteries
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Conclusions and Recommendations
One of the most valuable aspects of the project was raising the awareness of the general
population about the incidence and risks of lead poisoning. ICENS also established useful
collaborations with the medical fraternity. Both outcomes helped to improve the discovery of
lead poisoned children and the care they receive.
Interventions, including the building of an awareness of the nature and risks of chronic lead
poisoning amongst health care providers and caregivers, helped to reduce the immediate and
future dangers of lead poisoning. In the longer term the reduction of blood lead levels in
children nationally will require concerted action not only in education and regulation but also by
adopting aggressive prevention and case management including the development of a small
public health unit which has this responsibility. The infrastructure and technical skills to do this
are available, and it is reasonable to expect that in the near future the blood lead levels of most
Jamaican children will meet international norms.
In summary, although there is an increased appreciation in Jamaica of the dangers, backyard lead
smelting is still being carried out. As such, there remain a substantial number of chronically lead
poisoned children who require suitable clinical and environmental interventions. The consequent
social and financial burdens, reduced intelligence and violent behaviour place demands on
society that are far from trivial and are quite unnecessary since lead poisoning is an entirely
preventable malady. This is becoming better understood and there are increased efforts to
manage lead pollution in the Jamaican environment.
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Medical and environmental interventions produce significant reductions in blood lead levels but
such interventions, to be effective, do require longer term monitoring and support.
35
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