Defining the components of chronic risk The evaluation of chronic risk relies primarily on the technical concepts of danger, exposure and impact. Danger: Intrinsic likelihood of the properties of a substance to cause harm to a living organism exposed or it, or to cause damage to people, goods or the environment. Dose: quantity of a substance that comes in contact with an organism. There is a distinction between external dose, the quantity of pollutant that comes in physical contact with [the external barrier of] the human organism and internal dose, the quantity of pollutants that penetrate biological systems once they have passed through the tissues separating internal and external environments. The dose-response relationship is the quantitative relationship between a dose (or a given concentration) of a substance and the biological changes observed in the exposed organism. Effect: biological or systemic phenomenon provoked by the properties of a substance. Effect refers to the objective consequence of exposure to a substance, independent of the characteristics of the exposed target. Effects may be direct or indirect, temporary or permanent, reversible or irreversible, reducible, irreducible or cumulative. Exposure: contact between a pollutant and a target (organism, system or population). There is a distinction between acute exposure, subchronic exposure, and chronic exposure based on the duration; the duration of different types of exposure may vary according to species. In humans, acute exposure is over a duration from several seconds to several days; subchronic exposure is exposure over several days to several months; and chronic exposure is exposure over several years to an entire lifetime. There are three categories of exposure pathway: inhalation (respiratory system), ingestion (digestive system) and cutaneous contact (epidermis). Impact: any modification to the health of living organisms, on the natural surroundings or components of it, induced by [the effects of] a substance. Impact may be positive or negative. In regulatory impact studies, impact means the transposition of the effect of a substance, activity or construction (industrial site, agricultural exploitation) onto the scale of the exposed target. Impact factors in the target’s sensitivity [to effects] and on comparing observed or anticipated modifications with a reference situation or state.
Defining the components of chronic risk The evaluation of chronic risk relies primarily on the technical concepts of danger, exposure and impact. Danger: Intrinsic likelihood of the properties of a substance to cause harm to a living organism exposed or it, or to cause damage to people, goods or the environment. Dose: quantity of a substance that comes in contact with an organism. There is a distinction between external dose, the quantity of pollutant that comes in physical contact with [the external barrier of] the human organism and internal dose, the quantity of pollutants that penetrate biological systems once they have passed through the tissues separating internal and external environments. The dose-response relationship is the quantitative relationship between a dose (or a given concentration) of a substance and the biological changes observed in the exposed organism. Effect: biological or systemic phenomenon provoked by the properties of a substance. Effect refers to the objective consequence of exposure to a substance, independent of the characteristics of the exposed target. Effects may be direct or indirect, temporary or permanent, reversible or irreversible, reducible, irreducible or cumulative. Exposure: contact between a pollutant and a target (organism, system or population). There is a distinction between acute exposure, subchronic exposure, and chronic exposure based on the duration; the duration of different types of exposure may vary according to species. In humans, acute exposure is over a duration from several seconds to several days; subchronic exposure is exposure over several days to several months; and chronic exposure is exposure over several years to an entire lifetime. There are three categories of exposure pathway: inhalation (respiratory system), ingestion (digestive system) and cutaneous contact (epidermis). Impact: any modification to the health of living organisms, on the natural surroundings or components of it, induced by [the effects of] a substance. Impact may be positive or negative. In regulatory impact studies, impact means the transposition of the effect of a substance, activity or construction (industrial site, agricultural exploitation) onto the scale of the exposed target. Impact factors in the target’s sensitivity [to effects] and on comparing observed or anticipated modifications with a reference situation or state.
