Hello, we will start the module on toxicology and microbiology with an introduction that will allow us to understand the place of these sciences in the HSE field.

Toxicology and microbiology will be interested in 2 types of risks.

Toxicology will be interested in chemical risks, while microbiology will be interested in biological risks.

These risks will concern an isolated person, a population or an environment.

This is true for chemical risk and biological risk.

If it is a biological risk, the source will be microorganisms, bacteria or viruses for example.

If it is a chemical risk, the source will be a molecule.

Here I gave you an example of glyphosate.

If this source comes in contact with an isolated individual at the top, or with a population, or with the environment in these living or non-living components, so the biosenose at the air-soil, we can observe an impact.

This impact, depending on the source, could be reversible or irreversible.

Thus, toxicology will allow us to understand the chemical risk in HSE and to have a first approach.

Human toxicology, environmental toxicology.

However, we will not deal with fire, explosive atmosphere, transport of dangerous materials, storage and chemical reactions.

Microbiology will allow us to have a first approach to biological risk.

We will address the following themes, biological risk and health, biological risk and environment, and then we will also be interested in the benefits of microorganisms for the environment, and they are extremely numerous.

However, we will not address the problems of alteration of a product by the presence of microorganisms, which is very important in food agro, for example.

And what I'm going to show you here, or remind you, is that of course the risk assessment approach that we talked about applies to these 2 risks, as to all the other risks.

If we take the project that you have carried out, the first thing that you are asked to do is to know the context of your company and the working situation and to have knowledge about the risks you are studying.

So, toxicology and microbiology allow you to have knowledge that will allow you to assess risks and in particular to make a quotation, a hierarchy that makes sense to be able to decide the acceptability of risks.

These scientific knowledge will also allow you to adapt your mastery in a better way to the situation.

This notion of control must then be planned and implemented and we must carry out a follow-up of this action plan.

In the context of biological risk and chemical risk, of course, we will rely on the 9 principles of prevention.

In the case of biological and chemical risk, we will of course focus on the 9 prevention principles.

I advise you to take a short break on the presentation so that you can reflect on these 9 principles.

Then you will go to the next slide So here are the 9 principles that you should have found and you probably have placed the risk assessment in principle number 2 So let's focus now on a little bit of vocabulary So you have to master the notion of risk situation, that you understand the distinction between exposure and effect, and that you have understood, now, at this time of the year, the difference between chronic and acute.

The chronic is something that is persistent, continuous or discontinuous, and that occurs over a long period, while the acute occurs over a short period.

So we can have chronic exposures and acute exposures, and chronic effects and acute effects.

In the middle, we have the notion of sub-chronic.

If we are interested in the environment and we take the definition of the ADEME concerning the exposure, we see that the high will go up to a few days.

The chronic will start at a year or even a few years.

Between the 2, we will have the sub-chronicle.

If we are now interested in health and safety at work, with the notion of exposure limit values for toxins that have a dose threshold, that is, there must be a certain dose for an effect.

We will find 2 types of limit exposure values.

Exposure limit values on the short term, that is, for high-end.

So if we exceed this limit value, even if it is only a short time, there will be a potential impact.

And then we will have chronic limit exposure values.

If we exceed them every day over a long period, there will be a potential impact that will develop over time.

We will talk here about chronic exposure limit values.

You see that It is not the same time scale as the environment.

Here we are in the order of a few moments, from the second minute or 5 minutes, until, for the chronic, we will be able can have chronic effects from a few weeks to a few months, or even a few years depending on the type of problem.

Let's now look at the effects, that is, the disease, the infection.

According to the WHO, a chronic infection is a long-term infection that usually evolves slowly.

They cite, for example, cancer, chronic respiratory infections, diabetes.

Regarding these infections, There are 2 opposite terms for these conditions.

A serious disease has to oppose a benign disease.

In the synonym of serious, we say severe.

A acute infection can be opposed to a chronic infection.

An acute infection can be serious or benign.

A chronic infection can be serious or benign.

Often, for chronic infections, we see that the beginning is progressive, that the duration is long, and that it is sometimes definitive, that the chronicity is alive in some cases.

For acute infections, it is the opposite.

Something rather brutal at the start and a short duration.

It can become chronic, we will talk about chronicization.

The prognosis involved in these conditions is of 3 types.

Either a healing with sequelae, or a healing without sequelae, or a death.

So, in conclusion, what is a dangerous situation?

We said that we needed a source, an interaction with the impactable element, and that it causes a potential impact.

To limit this potential impact, and to limit this interaction, we will work on the control.

You are aware, you saw it in S1, that the control can play both on the probability of the interaction or on the potential impact.

At the end of the year, you should have clearly understood the notion of high exposure and chronic exposure.

And so, with the explanations provided, you should also have understood what is a high effect and what is a chronic effect.

Now let's move on to the last part of this support, the risk assessment.

First, a little personal work, what are the criteria that allow to assess a risk?

And then the second question you will answer, are these criteria the same for the high risk and for the chronic risk?

So you take a break to think about these questions and then you will move on to the next slide.

So what you probably found, you remember that in S1 we talked about the criticality and the criticality depends on 2 elements the gravity and the probability of the occurrence of the unwanted event.

If we look a little bit in the standards we will try to understand in the end, what is a risk?

Because in fact, in toxicology and microbiology, we will have to find elements, criteria that will allow us to understand this risk.

And therefore to understand this risk in all its dimensions.

Let's take the table of the lexicon of the PCA guide of the SGDSN.

They have taken the definition of the risk in ISO 73000 and it is said at the top that it is the effect of uncertainty on the achievement of the objectives.

What I have explained to you below is that there is a norm called 31000 which abandons the vision of the engineer, the 1 I presented to you previously, the risk being in the engineer's vision the combination of probability of event and its consequence.

The 31000 prefers to couple the risks to the objectives of the organization and to use the definition I gave you earlier the risk being the effect of uncertainty on the objectives So we observe 2 aspects, 2 concepts In the end, how will a risk be defined?

We will remember that a risk will be defined by its sources, the sources of risk, trigger events or a trigger event, consequences with certain gravity, and we will have to ask ourselves the question if this set is plausible or not.

And we're going to talk about plausibility.

In some cases, we will be able to work on probability.

It is the possibility that something happens, while probability is a measure of the chances of occurrence, and therefore expressed by a number.

If we take this number between 0 and 1, 0 means it is impossible and 1 means absolute certainty.

This brings us to resume the notion of risk modeling which we had already discussed in major natural risks.

To define a risk, we will first have to understand the sources of risk, the potential events and the potential consequences.

This set here will have a real semblance We already modeled this kind of reflection in S1 For example, concerning the environment we find here the same notion with a source of danger, with its intrinsic property which is the danger.

The impact that is made by an interaction between this source of danger and the impactable element, so this is what we called the impacting aspect.

And the impact could be local, regional or planetary.

You started a risk assessment process, you understood the context of your company, and then you looked for potential danger sources and interactions with an individual.

Here I represented a potential danger source and interaction with an individual.

If there are interactions, there is a potential impact.

You looked at what the existing masteries were and sometimes you asked yourself what could be added as mastery to limit the impact, even if you were not necessarily asked to think about it in this context.

Whether in biological risk or toxicological risk, we will find ourselves exactly with this model.

We will have to try to understand what are the sources of danger.

So, in microbiology, we'll talk about microorganisms, so we'll be on the biological risk.

So, in toxicology, we'll talk about molecules, we'll be on chemical products.

And so, we'll also try to understand the impacts on the individual, the population or the environment.

So the second question you asked is, are these the same criteria for acute and chronic risk?

You have already worked on this in terms of short vibrations, and you understood that for chronic, doses had to be calculated, so the notion of duration had to be used in order to determine this dose.

In the case of biological risk, we can treat this risk as being a risk almost only acute, except for allergies.

And the chemical risk, on the other hand, there will be situations both acute and chronic.

So we are talking about toxicology, we are talking about molecules, we are talking about the effects of these molecules on health, we are talking about chemical risk.

In microbiology, we will talk about microorganisms, and we will talk about the effects of these microorganisms on health.

In negative terms, we will be on the biological risk, but let's not forget that the majority of microorganisms, the ultra-majority of microorganisms, bring us health benefits, or for the environment.

We have now finished this first part of the module.

I wish you a good morning, a good afternoon or a good evening.

I don't know what time you did this course.

Before moving on to the next sequence, take the time to understand everything that has been said here.


Speaker 0: Hello, we will start the module on toxicology and microbiology with an introduction that will allow us to understand the place of these sciences in the HSE field. Toxicology and microbiology will be interested in 2 types of risks. Toxicology will be interested in chemical risks, while microbiology will be interested in biological risks. These risks will concern an isolated person, a population or an environment. This is true for chemical risk and biological risk.

Let's take a source. If it is a biological risk, the source will be microorganisms, bacteria or viruses for example. If it is a chemical risk, the source will be a molecule. Here I gave you an example of glyphosate. If this source comes in contact with an isolated individual at the top, or with a population, or with the environment in these living or non-living components, so the biosenose at the air-soil, we can observe an impact.

This impact, depending on the source, could be reversible or irreversible. Thus, toxicology will allow us to understand the chemical risk in HSE and to have a first approach. We will address several themes. Human toxicology, environmental toxicology. However, we will not deal with fire, explosive atmosphere, transport of dangerous materials, storage and chemical reactions.

You will see this in other modules. Microbiology will allow us to have a first approach to biological risk. We will address the following themes, biological risk and health, biological risk and environment, and then we will also be interested in the benefits of microorganisms for the environment, and they are extremely numerous. However, we will not address the problems of alteration of a product by the presence of microorganisms, which is very important in food agro, for example. So, 2 risks.

And what I'm going to show you here, or remind you, is that of course the risk assessment approach that we talked about applies to these 2 risks, as to all the other risks. If we take the project that you have carried out, the first thing that you are asked to do is to know the context of your company and the working situation and to have knowledge about the risks you are studying. So, toxicology and microbiology allow you to have knowledge that will allow you to assess risks and in particular to make a quotation, a hierarchy that makes sense to be able to decide the acceptability of risks. These scientific knowledge will also allow you to adapt your mastery in a better way to the situation. This notion of control must then be planned and implemented and we must carry out a follow-up of this action plan.

In the context of biological risk and chemical risk, of course, we will rely on the 9 principles of prevention. Normally, I think you remember them. In the case of biological and chemical risk, we will of course focus on the 9 prevention principles. I think you remember them. I advise you to take a short break on the presentation so that you can reflect on these 9 principles.

Then you will go to the next slide So here are the 9 principles that you should have found and you probably have placed the risk assessment in principle number 2 So let's focus now on a little bit of vocabulary So you have to master the notion of risk situation, that you understand the distinction between exposure and effect, and that you have understood, now, at this time of the year, the difference between chronic and acute. The chronic is something that is persistent, continuous or discontinuous, and that occurs over a long period, while the acute occurs over a short period. So we can have chronic exposures and acute exposures, and chronic effects and acute effects. In the middle, we have the notion of sub-chronic. If we are interested in the environment and we take the definition of the ADEME concerning the exposure, we see that the high will go up to a few days.

The chronic will start at a year or even a few years. Between the 2, we will have the sub-chronicle. If we are now interested in health and safety at work, with the notion of exposure limit values for toxins that have a dose threshold, that is, there must be a certain dose for an effect. We will find 2 types of limit exposure values. Exposure limit values on the short term, that is, for high-end.

So if we exceed this limit value, even if it is only a short time, there will be a potential impact. And then we will have chronic limit exposure values. If we exceed them every day over a long period, there will be a potential impact that will develop over time. We will talk here about chronic exposure limit values. You see that It is not the same time scale as the environment.

Here we are in the order of a few moments, from the second minute or 5 minutes, until, for the chronic, we will be able can have chronic effects from a few weeks to a few months, or even a few years depending on the type of problem. Let's now look at the effects, that is, the disease, the infection. According to the WHO, a chronic infection is a long-term infection that usually evolves slowly. They cite, for example, cancer, chronic respiratory infections, diabetes. Regarding these infections, There are 2 opposite terms for these conditions.

A serious disease has to oppose a benign disease. In the synonym of serious, we say severe. A acute infection can be opposed to a chronic infection. An acute infection can be serious or benign. A chronic infection can be serious or benign.

Often, for chronic infections, we see that the beginning is progressive, that the duration is long, and that it is sometimes definitive, that the chronicity is alive in some cases. For acute infections, it is the opposite. Something rather brutal at the start and a short duration. It can become chronic, we will talk about chronicization. The prognosis involved in these conditions is of 3 types.

Either a healing with sequelae, or a healing without sequelae, or a death. So, in conclusion, what is a dangerous situation? We said that we needed a source, an interaction with the impactable element, and that it causes a potential impact. To limit this potential impact, and to limit this interaction, we will work on the control. You are aware, you saw it in S1, that the control can play both on the probability of the interaction or on the potential impact.

At the end of the year, you should have clearly understood the notion of high exposure and chronic exposure. And so, with the explanations provided, you should also have understood what is a high effect and what is a chronic effect. Now let's move on to the last part of this support, the risk assessment. First, a little personal work, what are the criteria that allow to assess a risk? And then the second question you will answer, are these criteria the same for the high risk and for the chronic risk?

So you take a break to think about these questions and then you will move on to the next slide. So what you probably found, you remember that in S1 we talked about the criticality and the criticality depends on 2 elements the gravity and the probability of the occurrence of the unwanted event. If we look a little bit in the standards we will try to understand in the end, what is a risk? Why understand that? Because in fact, in toxicology and microbiology, we will have to find elements, criteria that will allow us to understand this risk.

And therefore to understand this risk in all its dimensions. Let's take the table of the lexicon of the PCA guide of the SGDSN. They have taken the definition of the risk in ISO 73000 and it is said at the top that it is the effect of uncertainty on the achievement of the objectives. What I have explained to you below is that there is a norm called 31000 which abandons the vision of the engineer, the 1 I presented to you previously, the risk being in the engineer's vision the combination of probability of event and its consequence. So probability and gravity.

The 31000 prefers to couple the risks to the objectives of the organization and to use the definition I gave you earlier the risk being the effect of uncertainty on the objectives So we observe 2 aspects, 2 concepts In the end, how will a risk be defined? We will remember that a risk will be defined by its sources, the sources of risk, trigger events or a trigger event, consequences with certain gravity, and we will have to ask ourselves the question if this set is plausible or not. And we're going to talk about plausibility. In some cases, we will be able to work on probability. So what is the true probability?

It is the possibility that something happens, while probability is a measure of the chances of occurrence, and therefore expressed by a number. If we take this number between 0 and 1, 0 means it is impossible and 1 means absolute certainty. This brings us to resume the notion of risk modeling which we had already discussed in major natural risks. To define a risk, we will first have to understand the sources of risk, the potential events and the potential consequences. This set here will have a real semblance We already modeled this kind of reflection in S1 For example, concerning the environment we find here the same notion with a source of danger, with its intrinsic property which is the danger.

The impact that is made by an interaction between this source of danger and the impactable element, so this is what we called the impacting aspect. And the impact could be local, regional or planetary. Let's take the example of your project. You started a risk assessment process, you understood the context of your company, and then you looked for potential danger sources and interactions with an individual. Here I represented a potential danger source and interaction with an individual.

If there are interactions, there is a potential impact. So you also thought about mastery. You looked at what the existing masteries were and sometimes you asked yourself what could be added as mastery to limit the impact, even if you were not necessarily asked to think about it in this context. Whether in biological risk or toxicological risk, we will find ourselves exactly with this model. We will have to try to understand what are the sources of danger.

So, in microbiology, we'll talk about microorganisms, so we'll be on the biological risk. So, in toxicology, we'll talk about molecules, we'll be on chemical products. And so, we'll also try to understand the impacts on the individual, the population or the environment. So the second question you asked is, are these the same criteria for acute and chronic risk? You have already worked on this in terms of short vibrations, and you understood that for chronic, doses had to be calculated, so the notion of duration had to be used in order to determine this dose.

In the case of biological risk, we can treat this risk as being a risk almost only acute, except for allergies. And the chemical risk, on the other hand, there will be situations both acute and chronic. So we are talking about toxicology, we are talking about molecules, we are talking about the effects of these molecules on health, we are talking about chemical risk. In microbiology, we will talk about microorganisms, and we will talk about the effects of these microorganisms on health. In negative terms, we will be on the biological risk, but let's not forget that the majority of microorganisms, the ultra-majority of microorganisms, bring us health benefits, or for the environment.

We have now finished this first part of the module. I wish you a good morning, a good afternoon or a good evening. I don't know what time you did this course. Before moving on to the next sequence, take the time to understand everything that has been said here. Take care, see you soon!

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Toxicologie support 1 intro 2020