Food Safety Systems
and Risk Assessment
The
most rudimentary processes that historically have been used to preserve foods
have also been used to keep foods safe where general principles of heating,
cooking, drying, cooling and salting that were reveled thousands of years ago
are still the methods by which food safety can be managed in the most basic of
settings. As food businesses and their customer base grew larger, distanced by
both space and time needs for food manufacturers to consider preservation as a
means of maintaining quality products has led to the evolution of modern food
safety systems and their accompanying programs. In today’s international
marketplace acceptable standards for food safety that use a common language and
achieve quality standards of practice are the goals that food safety
practitioners focus their attention upon. Considering the context of food safety,
assessment of risk and mitigation of risk are the most important part of food
safety management systems available. All the HACCP based food safety management
systems apply risk assessment as the key criteria to finalize critical control
points where prevention and mitigation is taking place to safeguard consumers
from the food safety hazards.
The
definition of risk is the "possibility of suffering harm or loss;
danger" as to the dictionary where scientists use the term risk when
assessing potential human health threats
from exposure to chemicals or pollutants in the
environment. Risk is equal to a person's exposure multiplied by
the toxicity of the chemical where exposure is a combination of
the concentration of the chemical; a person is exposed to and the
length of time they are exposed to that chemical. Toxicity is a measure of the
degree to which something is poisonous and is often expressed as a
dose-response relationship. Almost every substance is toxic at some dosage, which
means; anything in a large enough quantity can be poisonous. For example, an
adult ingesting half a cup (400 grams) of salt can be fatal, not only that even
water, if consumed in large quantities that can be fatal.
The
risks from the foods are also assessed in the same way, but process of risk
assessment can be explained as a continuous event, which follows the following
order while it practiced. Thus you need to reconsider your risk assessments
time to time and consider if there are any new risks has been exposed to the
product after initial assessment is conducted.
Estimation of Risks
Estimating
risk is a complicated process which involves taking data and multiplying it by
a risk factor to determine the likelihood of a health effect. The
data must be collected using methods approved for risk assessments and must be
verified. I.e. take product samples, measures the chemical levels in the
samples and determines if the chemical levels pose a risk to human health. The
data is then compared to acute thresholds, chronic thresholds and the
probability of disease development.
Exposure and
Symptoms
However,
the measurements used to determine risk can be very confusing because they are
made in unfamiliar quantities. For example, when we speak of exposure, measurements
such as micrograms per cubic meter (µg/m3) are sometimes used. Micrograms per
cubic meter describe the concentrations of chemicals in the environment.
Concentrations of chemicals in air are typically measured in units of the mass
of chemical (milligrams, micrograms) per volume of air (cubic meter).
However, concentrations may also be expressed as parts per million
(ppm) or parts per billion (ppb) by applying a conversion
factor. The formula to convert a concentration from micrograms per meter cubed
to parts per billion is based on the molecular weight of the chemical and is
different for each chemical. Also, atmospheric temperature and pressure affect
the calculation. Most of the time a standard atmospheric temperature (25 °C)
and atmospheric pressure (1 atm) are used.
Some
health problems occur very soon after a person is exposed to a hazard. Symptoms
or illnesses occurring from short-term exposure are called acute effects.
The immediate effects may be minor (i.e. vomiting, nausea, skin allergies,
watery eyes, rash, throat irritation) and may go away once a person is no
longer exposed to the hazard. However, some acute exposures may cause
serious problems, such as damage to the nerve system. Other health problems may
not appear unless a person is exposed to a hazard for many years. These effects
are a result of long-term exposure and are called chronic effects. The
threshold for chronic effects is usually much lower than the threshold for
acute effects since hazard can build up in the body over time.
Process Initiation
The
first task is called process initiation – getting started on responding to your
customers’ requirements. One strategy is to proceed in the following manner.
Stage 1: Assemble a
team
As
for food safety management system planning, you need a team that covers a range
of disciplines:
A food technologist
with knowledge of specific processes and products;
A food
microbiologist who knows about microbial ecology;
A statistician to
assemble and handle data;
A manager to direct
the work
As
the manager, it is your task to find the specialists needed to undertake the
risk assessment work on behalf of the company. In larger countries with a
history of product (e.g. Ice Cream/Soft Drinks) exports, this will not be a
great problem. In smaller countries, however, we may need help. Together with
WHO, FAO and CODEX has prepared a number of texts, which take you to advanced
levels in risk assessments.
Stage 2: Survey the
industry
Make
a survey of all the products you manufacture and the countries to which you
export. This is a straightforward task since every nation keep records.
Stage
3: Survey product-related illness
Do
a preliminary study of product-related (e.g. Ice Cream/Soft Drink) illnesses in
the country as well as in countries to which you export. This will set the
scene for doing a risk profiling exercise.
If
your Health Department keeps records of food poisoning incidents, that is a
good place to start your survey. You can make a list of Product-related incidents,
linking products with hazards (micro-organisms and toxins) and include these
hazards: product pairs in the risk profile. In many countries, however,
resources are so scarce that keeping statistics is not a high priority so you
should spend some time searching and talking to people who would be likely to
know of any illnesses caused by consumption. This is purely anecdotal evidence
but has some value – therefore make notes of your conversations. The next stage
is to look for statistics from customer countries. If you have Internet access,
there are a number of Web sites, where information on food poisonings is
included.
Once
you have gathered data, assemble them into a summary table. A collection of
outbreaks of seafood-related illness in the United States and Australia over
the period 1990–2000 is an example of the hazards and products involved in
those countries.
The
data are valuable because they:
Identify the main
hazards;
Provide background
on what has caused problems in importing countries.
If
you look a little more carefully at the data, you can make a list of hazards
and products that will shape your risk profiling exercise.
If
you look a little more carefully at the data, you can make a list of hazards
and products that will shape your risk profiling exercise.
You
now have a list that can form the basis of your risk profile. There may be
other perceived issues that need to be added to the list. Some countries
perceive these as food safety issues and they also become trade issues, so they
are important, and you may wish to assemble some information on them.
Stage 4: Do a risk
profile
If
you do a risk profile of the industry as a whole this will give you a focus on
products and pathogens of most concern. For the purpose of this document, risk
profiling is defined as “a description of a food safety
problem and its context developed for the purpose of identifying those elements
of a hazard or risk that are relevant to risk management decisions”.
This
phase of the work entails gathering data in three areas:
Hazard
identification
Hazard
characterization
Exposure assessment
Once
this is done, you will know which pathogen: product pairings should be
investigated as a matter of priority.
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