As part of the presentation of projects integrated in the Center for Environmental and Marine Studies (CESAM), we spoke with Susana Loureiro (CESAM/DBIO), the researcher responsible for the University of Aveiro’s participation in the European project PARC. In this conversation, we sought to learn more about the objectives and specific characteristics of this “European Partnership for the Assessment of Risks from Chemicals – PARC.”

CESAM: How did the PARC project come about?

Susana Loureiro: This project came about as a result of a previous partnership, the HBM4EU project (Human Biomonitoring for Europe – Science and Policy for a healthy future), which was a human biomonitoring project where various institutions aimed to monitor the accumulation of different types of chemicals in humans – such as metals, mycotoxins, polycyclic aromatic substances, and others.
Based on the results of this project, which successfully established risk assessment in various European populations, the European Union decided that it was very important to continue this project and extend the consortium to the environmental aspect. Therefore, this European partnership for chemical risk assessment [PARC project] began with a set of risk assessment partners for the human component and then supplemented with partners who had competencies in the environmental area.
This project is a partnership with the member states, since each member state chooses the national partners. In Portugal, there are two beneficiary partners, the Ricardo Jorge Health Institute and the Faculty of Medicine of the University of Lisbon. These two organisations chose affiliated partners: us [CESAM/UA], the UC, the Higher School of Health, the General Directorate of Health, etc. We were explicitly contacted because of our competencies in environmental risk assessment.

CESAM: When discussing risks, what exactly are we talking about?

Susana Loureiro: For us to evaluate whether there is potential for risk to human or environmental health, or in other words, the potential for a visible and felt impact on the population… the population also feels environmental impacts, directly or indirectly… we have two components: the exposure component and the effects component. Then we will assess the probability of these effects occurring, assigning a value to the risk, and this quantification will provide information about the existence of that risk.
Whenever the effects [on living organisms] occur at concentrations [of the chemical] lower than those in the environment, we know there is a risk. If the effects occur only at concentrations [of the chemical] higher than those in the environment, then there is no risk. In other words, if the concentrations are minimal, and the effects only occur at much higher concentrations, the risk is minimal or nil. When they approach each other [environmental concentrations and concentrations that cause effects], then there is a probability of risk.

CESAM: When discussing chemical risks, are we referring to chemicals of all kinds? From medications to food?

Susana Loureiro: Yes, we can divide this into two types of substances: those that occur naturally in the environment and those that are anthropogenic in production.
Even those that occur in the environment, for example, from mining operations, the mine exists and occurs naturally, meaning that the ore present there occurs naturally. The mining activities make these metals available and release them from their original location. By doing so, we increase the concentrations of these metals in that area… which was unexpected because they were all concentrated in the same place and in a less available form to organisms. These substances exist in nature, such as lead, zinc, copper, and all the metals that exist naturally.
Then we have synthesised substances like drugs and pesticides, which, in some cases, have a biological basis, meaning the molecule exists but is synthesised and prepared for a specific purpose and later released into the environment directly or indirectly. In the case of pesticides, they are applied directly, while in the case of drugs, they appear more indirectly because they are used by humans and then pass through wastewater treatment plants before entering the environment. If it’s a drug used in veterinary medicine, it reaches the environment more quickly through animal waste.

CESAM: Earlier, you used the term “environmental health.” It’s a term that is rarely used in our everyday language…

Susana Loureiro: And I always like to emphasise it because there are different types of exposures in humans, and we associate our exposure only with food. While it is true that if we eat fish contaminated with some chemical substance, we will ingest it. Therefore, if the oceans are polluted, it will affect us. In the case of microplastics, if a fish ingests them and they accumulate in parts of the fish we eat, we will ingest the microplastics.
However, there are many chemical substances that we are exposed to in our daily lives that influence us. For example, why are there so many fertility problems nowadays that did not exist before? Why do so many women have difficulty getting pregnant? Because something is happening with either the man, the woman, or both. In most cases, it is not related to the genetics of both individuals but to the environmental component. Our physiology can be altered entirely by one of these factors: genetic factors, environmental factors, or the combination of both… or it could be something we are not yet aware of.
And often, the explanation lies in the environmental factor, or the environmental factor combined with genetics. These environmental factors are mostly the chemical substances to which we are exposed every day, from our food and personal hygiene products to the cleaning products we use at home and the substances we are exposed to at work and in our daily lives. We are exposed to thousands of chemical substances per year, leading to a drastic decrease in fertility levels.

CESAM: How do you decide which substances to evaluate?

Susana Loureiro: The European Union has a list of priority substances, which is constantly changing… actually, it keeps growing because, unfortunately, it doesn’t decrease.
Then there are substances considered emerging, which are identified as a new problem. Sometimes it can be a problem identified immediately or something that we suspect will cause a problem. For example, microplastics are something for which the exact issues they will cause are not 100% proven. In comparison to macroplastics, we know the problems they cause for marine animals. However , microplastics are more difficult, even though we know they will likely cause problems. And that’s why they are considered emerging substances.
Then [the criteria for inclusion in this list] are very much focused on the effects. Some effects are considered priorities… for example, substances that cause carcinomas, go straight to the top, they are the most prioritised ones. And then we have others that cause DNA alterations, and endocrine disruption, which is also one of the most pressing effects because endocrine dysfunction is associated with fertility, reproduction, and several essential functions.
We also have neurotoxicity, which is associated with the central nervous system and therefore acquires a priority status. Understanding and generating knowledge about substances that have these types of effects is urgent.

CESAM: In conclusion, what stage is the project in, and what are the next steps?

Susana Loureiro: PARC started in May 2022, and having a partnership with national governmental institutes is something unprecedented and very complex to coordinate… in addition to that, it has another peculiarity: it lasts for seven years. European projects usually have a maximum duration of 4 years.
Within this partnership, there will be hundreds of small projects . For each of them, a budget is required, partners are needed, and a defined work plan is needed… so, this first year was focused a lot on that, although we are already doing some work… it was mostly about organization and preparation. Many of the working groups will start doing “real” work in the second semester of the first year.
Because it is very complex to define a 7-year work plan… in 7 years, science evolves a lot, and new approaches and new chemical structures emerge that need to be addressed… and we also want to take a step forward in risk assessment and create what is called “new generation risk assessment (NGRA).”
NGRA is focused on reducing the number of tests, such as reducing the practical evaluation of effects by reducing tests on animals (especially vertebrates – mice, fish – and cephalopods – octopuses, squids). To achieve this, computational methodologies or “in vitro” methodologies are used, which employ computational approaches or cells, organelles, organoids… all highly organised biological structures but at a lower level of biological organisation, such as tissues or cells. This is to provide an understanding of the effects without the need for animal testing.

Another area we want to advance in is the evaluation of chemical mixtures…

CESAM: …chemical mixtures?

Susana Loureiro: Yes, because we are not exposed to just one chemical substance, and risk assessment is often done on a chemical-by-chemical basis without considering the cumulative risk. It’s always like: “Is there a risk for this substance? No”; “Is there a risk for this other substance? No.”
But the truth is, if we add up the minimum risk of these substances, does it not create a higher risk? Let me give you an example: imagine that a particular chemical substance, at a given concentration, induces a 10% effect… a 10% effect, whatever it may be that we are measuring, is something that can often be derived from chance (10%). But if we have ten chemical substances that each cause a 10% effect, and if we add them all up, you end up with a more significant effect. In this case, if you do the math, you have a total effect of 100%!
Currently, what is assessed is chemical by chemical, independent of the presence of others.

For more information about the PARC project, access this link.
This partnership has received funding from the European Union’s Horizon Europe research and innovation programme under Grant Agreement No 101057014