6.3 Hazard Identification (Step 1)
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consider is provided here for human toxicity (Sect. 6.3.1) and for environmental
toxicity (Sect. 6.3.2).
6.3.1 Human Toxicity
A risk assessment of a product for adverse effects on humans aims to clarify any
potential toxic effects during the life cycle of the product for directly exposed
populations, such as workers and consumers. In addition to direct exposure, possible
effects due to indirect environmental exposure (i.e., through food, drinking water,
and respiratory air) are also a target of the investigation, with the inhalation and oral
and dermal exposure routes considered.
Identified hazards to human health often include the following toxicity types (van
Leeuwen and Vermeire, 2007; ECHA, 2011):
• Acute toxicity: A substance’s ability to cause adverse effects on human health
that occur very soon after exposure (on the order of seconds, minutes, hours, or
days).
• Sub-chronic or chronic toxicity: A substance’s ability to cause adverse effects
that occur following long-term, repeated exposure. Sub-chronic effects occur
from repeated exposure over several weeks or months, and chronic effects occur
from exposure over many months or years. (Note: In general, the definition
of “chronic” is in relationship to the lifetime of the organisms of the species
considered.)
• Mutagenicity: Mutagenic substances can cause permanent, transmissible changes
(mutations) in the genetic material of a cell.
• Carcinogenicity: Carcinogenic substances can act as an initiator or promoter of
abnormal cell growth and differentiation that can lead to cancer. Two mechanisms
that have been distinguished for assessment of this are (1) genotoxic carcinogens
that cause cancer as a result of direct contact to DNA and (2) non-genotoxic
carcinogens that cause their carcinogenic effects not via the DNA, but, for
example, via specific receptors.
• Reproductive toxicity: This term summarizes adverse effects on a developing
embryo or fetus caused either by a chemical directly acting on its cells or by
a chemical inducing mutation in a parent’s germ cell.
• Irritation and corrosivity: Irritating substances can cause inflammation when in
contact with certain tissues, e.g., skin, eyes, or mucous membranes. Corrosive
substances can destroy living tissue they contact.
• Sensitization: Sensitizers are substances that, when inhaled or absorbed through
the skin, cause an allergic reaction and lead to a more pronounced reaction when
there is contact with the substance in the future.
A chemical product can be tested for each of these toxicity types. For decades,
this has been done often by using standardized animal studies and then using those
results to estimate how a human would respond to the same exposure. For acute
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consider is provided here for human toxicity (Sect. 6.3.1) and for environmental
toxicity (Sect. 6.3.2).
6.3.1 Human Toxicity
A risk assessment of a product for adverse effects on humans aims to clarify any
potential toxic effects during the life cycle of the product for directly exposed
populations, such as workers and consumers. In addition to direct exposure, possible
effects due to indirect environmental exposure (i.e., through food, drinking water,
and respiratory air) are also a target of the investigation, with the inhalation and oral
and dermal exposure routes considered.
Identified hazards to human health often include the following toxicity types (van
Leeuwen and Vermeire, 2007; ECHA, 2011):
• Acute toxicity: A substance’s ability to cause adverse effects on human health
that occur very soon after exposure (on the order of seconds, minutes, hours, or
days).
• Sub-chronic or chronic toxicity: A substance’s ability to cause adverse effects
that occur following long-term, repeated exposure. Sub-chronic effects occur
from repeated exposure over several weeks or months, and chronic effects occur
from exposure over many months or years. (Note: In general, the definition
of “chronic” is in relationship to the lifetime of the organisms of the species
considered.)
• Mutagenicity: Mutagenic substances can cause permanent, transmissible changes
(mutations) in the genetic material of a cell.
• Carcinogenicity: Carcinogenic substances can act as an initiator or promoter of
abnormal cell growth and differentiation that can lead to cancer. Two mechanisms
that have been distinguished for assessment of this are (1) genotoxic carcinogens
that cause cancer as a result of direct contact to DNA and (2) non-genotoxic
carcinogens that cause their carcinogenic effects not via the DNA, but, for
example, via specific receptors.
• Reproductive toxicity: This term summarizes adverse effects on a developing
embryo or fetus caused either by a chemical directly acting on its cells or by
a chemical inducing mutation in a parent’s germ cell.
• Irritation and corrosivity: Irritating substances can cause inflammation when in
contact with certain tissues, e.g., skin, eyes, or mucous membranes. Corrosive
substances can destroy living tissue they contact.
• Sensitization: Sensitizers are substances that, when inhaled or absorbed through
the skin, cause an allergic reaction and lead to a more pronounced reaction when
there is contact with the substance in the future.
A chemical product can be tested for each of these toxicity types. For decades,
this has been done often by using standardized animal studies and then using those
results to estimate how a human would respond to the same exposure. For acute