Dr. Tawfik A. M. Khoja

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OCCUPATIONAL HEALTH RISK ASSESSMENT

• Dr. Tawfik A. M. Khoja
• MBBS, DPHC, FRCGP, FFPH (UK)
• Director General GCC
• Health Ministers Council

TO BE PRESENTED IN THE OCCUPATIONAL HEALTH AND
SAFETY CONFERENCE Muscat Sultanate of
Oman 20-22 Dhul-Qada 1427 H / 11-13 December 2006
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(No Transcript)
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IN THE NAME OF ALLAH, THE MOST GRACIOUS, THE MOST
MERCIFUL
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Introduction
Chemicals can be either beneficial or harmful,
depending on a number of factors, such as the
amounts to which we are exposed.
are used to determine if
a particular chemical poses a significant risk or
problem to human health and, if so, under what
circumstances.
Health risk assessments
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How much of the chemical would someone have to be
exposed to before it would be dangerous? How
serious could the health risks be?
What
activities might put people at increased risk?
( The total removal of harmful pollutants from
environment is often infeasible or impossible,
and many naturally occurring substances also pose
health risks ).
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Risk assessment helps scientists and regulators
identify serious health hazards and determine
realistic goals for reducing exposure to toxics
and threat to the public . Estimating the
hazards posed by toxic chemicals in the
environment involves the compilation and
evaluation of complex sets of data . These
perform or assist by specialists include
scientists in toxicology and epidemiology as
well as physicians, biologists, chemists, and
engineers .
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As broadly defined, RISK ASSESSMENT can be used
to predict the likelihood of many unwanted events
including industrial explosions, workplace
injuries, failures of machine parts, natural
catastrophes, injury or death from an array of
voluntary activities, diseases, natural causes,
life-style or others.
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HEALTH RISK ASSESSMENT is a separate and
distinct discipline which uses toxicology data
collected from animal studies and human
epidemiology, combined with information about the
degree of exposure, to quantitatively predict the
likelihood that a particular adverse response
will be seen in a specific human population.
The risk-assessment process has been used by
agencies for almost 40 years, most notably within
the U.S. Food and Drug Administration (FDA).
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With the emergence of quantitative methods,
risk-assessment models can better estimate the
probability that a specific adverse effect will
occur over a wide range of doses. Since 1980,
many environmental regulations and some
occupational health standards have been based on
the results of low-dose extrapolation models and
exposure assessments.
Cont.
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For example, risk-assessment methodologies have
been used to set standards for pesticide
residues, food additives, pharmaceutical agents,
drinking water, soil and ambient air.
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RISK ASSESSMENT, by its very nature, is a process
whereby the magnitude of a specific risk is
characterized so that decision makers can
conclude whether the potential hazard is
sufficiently great that it needs to be managed or
regulated.
Before deciding to conduct such analyses, one
must concede that some level of risk can be
deemed acceptable that is, a risk-benefit
balance can be found.
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Some nations
, have traditionally
regulated chemicals to reduce emissions and
exposure to the lowest level achievable using
engineering controls or to impose a
ban. Reducing health risks to levels that are
"as low as reasonably achievable" (ALARA) or
requiring the use of the "best available
technology" (BAT) can produce significant
reductions in the degree of exposure .
Cont.
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First, adopting an ALARA or BAT approach can be
costly and may not result in an appreciable
overall benefit (reduction of risk) to
society. Second, a reliance on banning may not
ensure that a significant or even measurable
level of risk reduction will occur.
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Risk characterization
This is the most important part of an
assessment, it summarizes and interprets the
information collected from previous activities
and identifies the limitations and the
uncertainties in risk estimates.
Cont.
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A risk is the probability (chance) , high or
low, that somebody could be harmed hazards,
together with an indication of how serious the
harm could be. The risk can either be
expressed mathematically, (0.5 a 50/50 chance)
"high/medium/low". The outcome would be a
musculoskeletal disorders (MSDs)
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What is a hazard ?
A hazard is something that has the potential to
cause harm. This harm can effect people, property
and processes as follows
People injury, illness, death, psychological
trauma Property Damage, contamination,
theft chemical, electricity and wastage
Process Work disruption working from ladders
and interruption to production.
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HAZARD IDENTIFICATION is the first and most
easily recognized step in risk assessment. It is
the process of determining whether exposure to an
agent could (at any dose) cause an increase in
the incidence of adverse health effects in humans
or wildlife.
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Dose-response evaluations define the relationship
between the dose of an agent and the probability
of a specific adverse effect in laboratory
animals. Exposure assessment quantifies
the uptake of xenobiotics from the environment by
any combination of oral, inhalation and dermal
routes of exposure.
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What is occupational risk assessment ?
Modern occupational safety and health legislation
usually demands that a risk assessment be carried
out prior to making an intervention.

• Biological agents
• Chemical agents
• Physical agents, including

• noise
• vibration
• ionizing radiation

Cont.
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• Physical hazards

• Slips and trips
• Falls from height
• Workplace transport
• Dangerous machinery
• Electricity

• Work related stress causal factors

Various models for conducting occupational health
risk assessment provide step-by-step guidance for
the identification and assessment of significant
occupational health hazards.
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Occupational risk assessment helps you to make
sure that you can weigh up whether you have taken
enough precautions or should do more to prevent
harm.
Accidents and ill health can ruin lives and
affect your business too if output is lost,
machinery is damaged, insurance costs increase or
you have to go to court.
The aim is to make sure that no one gets hurt or
becomes ill.
Cont.
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You are legally required to assess the risks in
your workplace so that you put in place a plan to
control the risks.
The importance things you need to decide are
whether a hazards is significant , and whether
you have than a careful examination of what, in
your work, could it covered by satisfactory
precautions so that the risk is small.
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How to assess the risks in the workplace
Step 1 Look for the hazards Step 2 Decide
who might be harmed and how Step 3 Evaluate
the risks and decide on precautions Step
4 Record your findings and implement them Step
5 Review your assessment and update if necessary
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HRA Vs Epidemiological Studies
The term health risk assessment is often
misinterpreted. People sometimes think that a
risk assessment will tell them whether a current
health problem or symptom was caused by exposure
to a chemical. This is not the case. HRA and
epidemiologic studies have different objectives.
Most epidemiologic studies evaluate whether past
chemical exposures may be responsible for
documented health problems in a specific group of
people.
Cont.
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In contrast, health risk assessments are used to
estimate whether current or future chemical
exposures will pose health risks to a broad
population, such as a city or a community.
Scientific methods used in health risk
assessment cannot be used to link individual
illnesses to past chemical exposures assessments.
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The Four-Step Process of Risk Assessment
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RISK ASSESSMENT PARADIGM
Risk assessment has (by convention) been
separated into four sub-disciplines 1) hazard
identification, 2) dose-response assessment, 3)
exposure assessment. and 4) risk
characterization. This has been called the
Risk Assessment Paradigm."
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Step 1 Hazard Identification
Scientists determine the types of health problems
a chemical could cause by reviewing studies of
its effects in humans and laboratory animals.
Depending on the chemical, these health effects
may include

• Short-term ailments, such as headaches nausea
  and eye, nose, and throat irritation
• Or chronic diseases, such as cancer.

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Effects on sensitive populations, such as
pregnant women and their developing fetuses,
children, the elderly, or those with health
problems (including those with weakened immune
systems those with pre-existing medical
conditions), must also be considered. Responses
to toxic chemicals will vary depending on the
amount and length of exposure.
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• The effects of the vast majority of chemicals
  often rely on animal studies to evaluate a
  chemicals health effects.

• Comparison of human and animal metabolism may be
  useful in selecting the animal species that
  should be studied, if similar effects were found
  in more than one species, the results would
  strengthen the evidence that humans may also be
  at risk.

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Step 2 Exposure Assessment
Scientists attempt to determine

• How long people were exposed to a chemical
• How much of the chemical they were exposed to
• Whether the exposure was continuous or
  intermittent
• And how people were exposedthrough eating,
  drinking water and other liquids, breathing, or
  skin contact.

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To estimate exposure levels, scientists rely on
air, water, and soil monitoring human blood and
urine samples or computer modeling. Although
monitoring of a pollutant provides excellent
data, it is time consuming, costly, and typically
limited to only a few locations.
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So
Scientists often rely on computer modeling, which
is relatively inexpensive and less time
consuming, also uses mathematical equations to
describe and assess how a chemical is
released ( industrial facilities ) and to
estimate the speed and direction of its movement
through the surrounding environment.
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Step 3 Dose-Response Assessment
Scientists evaluate the information obtained
during the hazard identification step to estimate
the amount of a chemical that is likely to result
in a particular health effect in humans. An
established principle in toxicology is that the
dose makes the poison. For example, a
commonplace chemical like table salt is harmless
in small quantities, but it can cause illness in
large doses.
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Scientists perform a dose-response assessment to
estimate how different levels of exposure to a
chemical can impact the likelihood and severity
of health effects. The dose-response
relationship is often different for many
chemicals that cause cancer than it is for those
that cause other kinds of health problems.
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Cancer Effects
For chemicals that cause cancer, the general
assumption in risk assessment has been that there
are no exposures that have zero risk unless
there is clear evidence otherwise. Very low
exposures to carcinogens might increase the risk
of cancer, if only by a very small amount.
Several factors make it difficult to estimate
the risk of cancer.
Cont.
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Cancer appears to be a progressive disease
because a series of cellular transformations is
thought to occur before cancer develops. Cancer
in humans often develops many years after
exposure to a chemical.
Collective data from new studies can be used to
improve estimates of cancer risks.
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Non-cancer Effects
Non-cancer health effects (such as asthma,
nervous system disorders, birth defects, and
developmental problems in children) typically
become more severe as exposure to a chemical
increases.
One goal of dose-response assessment is to
estimate levels of exposure that pose only a low
or negligible risk for non-cancer health effects.
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Step 4 Risk Characterization
The last step in risk assessment brings together
the information developed and dose response
assessments to describe the resulting health
risks that are expected to occur in the exposed
population. Scientists analyze the information
developed during the exposure is presented in
different ways for cancer and non-cancer health
effects, as explained as follow
Cont.
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Cancer Risk
Cancer risk is often expressed as the maximum
number of new cases of cancer projected to occur
in a population of one million people due to
exposure to the cancer-causing substance over a
70-year lifetime. For example, a cancer risk of
one in one million means that in a population of
one million people, not more than one additional
person would be expected to develop cancer as the
result of the exposure to the substance causing
that risk.
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An individuals actual risk of contracting
cancer from exposure to a chemical is often less
than the theoretical risk to the entire
population calculated in the risk assessment.
For example, the risk estimate for a
drinking-water contaminant may be based on the
health-protective assumption.
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Moreover, an individuals risk not only depends
on the individuals exposure to a specific
chemical but also on his or her genetic
background (i.e., a family history of certain
types of cancer) health diet and lifestyle
choices, such as smoking or alcohol consumption.
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How Health Risk Assessment Is Used
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Risk managers rely on risk assessments when
making regulatory decisions, such as setting
drinking water standards, or developing plans to
clean up hazardous waste sites. Risk
managers are responsible for protecting human
health, but they must also consider public
acceptance, as well as technological, economic,
social, and political factors, when arriving at
their decisions.
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For example, they may need to consider how much
it would cost to remove a contaminant from
drinking water supplies or how seriously the loss
of jobs would affect a community if a factory
were to close due to the challenge of meeting
regulatory requirements that are set at the most
stringent level. Health risk assessments can
help risk managers weigh the benefits and costs
of various alternatives for reducing exposure to
chemicals.
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One of the most difficult questions of risk
management is How much risk is acceptable? !
While it would be ideal to completely eliminate
all exposure to hazardous chemicals, it is
usually not possible or feasible to remove all
traces of a chemical once it has been released
into the environment.
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The goal of most regulators is to reduce the
health risks associated with exposure to
hazardous pollutants to a negligibly low level.
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Risk Assessment of Work Related Stress
Definition work related stress as "the adverse
reaction people have to the excessive pressures
or other types of demand placed on them".
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Principles
Stressors need to be assessed by the same
methodology as other work related hazards. Heads
of departments of the organization are required
to appoint one or more persons (who are senior
employees, qualified, and trainaed members) in
their department to carry out the necessary risk
assessments, judgments and to recommend
appropriate actions.
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FACTORS TO BE CONSIDERED BY ASSESSORS ARE
Demands - such as workload, fear of exposure to
physical hazards etc Control - the degree of
control an employee in their role/job has in the
work that they do Relationships - in particular
harassment or bullying in the department Change
- the way organizational change is managed and
communicated in the department
Cont.
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Role - whether an employee understands their role
in the department and in particular if any one
employee has conflicting roles Training -
whether training has been provided to enable
employees to undertake the core functions of
their job Support - provided by peers and line
managers Individual factors - whether allowance
has been made for individual differences.
Cont.
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A checklist can be used to identify role or
individual's stressors. Experiencing one or
more stressors does not necessarily lead to the
experience of stress. Non- work related factors
often impact on work related stressors.
Cont.
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A proportion of employee stress in the workplace
arises from factors outside of work. However,
non-work and work based stressors can act
together and may lead to problems. Quantitative
assessments should include sickness absence and
work performance measure against reasonable
expectation..
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Evaluating the risk
Assessors should consider what action is already
being taken, whether it is enough or what more is
needed. Assessments should be carried out

• On request from an individual employee,
• Where an individual's role or a section in a
  department with a high level of stress has been
  identified.
• When managers have concerns about a group of
  staff or a unit.
• When there is good reason to believe that an
  employee has stress related illness.

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Records
Where an assessment has been carried out the
significant findings should be recorded. Heads
or administrators need to discuss the results of
the assessment with the individual or individuals
concerned. Departments must be aware of the Data
Protection Act requirements. There is no need to
make intrusive enquiries of a personal nature or
to record sensitive personal data.
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Departmental action list
(a) Appoint assessors and arrange for their
training and capacity building. (b) Carry out
assessment. (c) Report to department
management. (d) Department management to liaise
over problems sympathetically with individual(s)
concerned.
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Early detection
The early detection of individuals experiencing
difficulties is vital and department managers are
encouraged to refer at as early a stage as
possible, individual(s) who they believe might
benefit from Occupational Health Service input.
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CONCLUSION
Current risk assessment methods, are often
frustratingly lacking in their ability to use all
available information rely on overly simplified
models and/or assumptions and foster a sense of
uncertainty surrounding health and environmental
policy-making.
Thus, desired outcomes of advancements in risk
assessment science.
Cont.
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Improved science underpinning of methods makes
the resultant data more useful because they can
be more reliably interpreted.
Risk assessment models based on more advanced
science will enable more cost-effective
risk-based management decisions because more
accuracy reduces over- and under-regulation.
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Access to high quality assessments is of high
value to all stakeholders, including government
that is mandated to protect the public and
environment, industry that seeks full knowledge
of its products through Responsible Care, and the
public who has a right to know.
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The knowledge and skills in the risk assessment
of work-related stress (occupational hygiene,
ergonomics, mental health) have increased in the
past few years. More emphasis should put on
other phases of risk analysis, i.e. risk
management and communication, which, however, are
sometimes even more important for the whole
society.
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TO VALID RISK ASSESSMENT, ALSO RATIONAL
MANAGEMENT AND RELIABLE COMMUNICATION ARE
ESSENTIAL REQUIREMENTS FOR SUSTAINABLE
DEVELOPMENT AND DECISION-MAKING. AT THE
ENTERPRISE LEVEL, POSITIVE, WELL-FUNCTIONING
COMMUNICATION IS A CRUCIAL ASPECT OF COMPANY
POLICY AND OCCUPATIONAL HEALTH RISK ASSESSMENT.
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RECOMMENDATIONS
1. Development of healthy work practices and
promotion of health at work. 2. Strengthening of
Occupational Health Services (OHS) and Health
risk assessments for all workers in all sectors
of the economy and in all enterprises, as well as
for the self-employed. The preventive
approach should be given the highest priority.
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3. Establishment of support services for
occupational health Health risk assessments
. 4. A national quality assurance and quality
management element should be included in
occupational health and Health risk assessments
programmes as well as an appropriate training
should be provided to responsible personnel.
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5. Development of occupational health standards
based on scientific risk assessment to ensure
minimum levels of health and safety at work are
applied.. The standards also serve as references
for assessment of the result of monitoring and
provide guidelines for planers. 6. Development
of human resources for occupational health and
Health risk assessments.
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7. Governments should ensure that the necessary
elements of occupational health will be included
in the basic training curricula of all who may in
the future deal with occupational health issues
(Health risk assessments ). 8. In all training
the need for a multidisciplinary approach should
be taken into consideration, ensuring involvement
of occupational medicine and nursing,
occupational hygiene, ergonomics and work
physiology, occupational safety , work
organization and other relevant fields.
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9. Establishment of information systems as well
as analysis of reliable data and establishment of
trends in occupational health, (Risks)
recognition of priorities at national and local
levels are of utmost importance both for
decision-making on policies, for occupational
health practices and Health risk
assessments. 10. Each country should review its
data and registration systems of occupational
diseases, accidents and risk data management. The
comparability of data should be ensured by
collaboration between the countries.
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11. Development of collaboration in occupational
health, Health risk assessments and with other
activities, so tripartite collaboration between
government, employers and trade unions in
implementation of occupational health activities
should be ensured by the establishment of formal
links with these bodies.
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Thank you for your kind attention
Wishing you all the best