Toxicology 11 – Risk assessment of compounds
What is risk?
Paracelsus; Everything is toxic, it depends on the dose.
Forward problem; what is the risk (response) of a given
exposure?
Backward problem; which exposure corresponds to an
acceptable risk (response?
Risk = hazard (gevaar) * exposure (blootstelling)
Risk is the probability that a negative effect will occur.
Risk assessment is just a part of the risk management.
Comparison of risks by toxic compounds to other risk factors
DALY (disability adjusted life years); express risks in terms of lost life years
DALY=YYL (years of life lost) * YLD (years lost to disability)
YYL; years lost due to premature death; n (aantal mensen) * standard life
expectation in year of death (verschil tussen leeftijd doodgaan en life
expectation)
YLD; years lived with disease; n (aantal mensen) * handicap weight * duration
diseases till recovery or death
Hoe can critical exposures be determined?
Hazard; Intrinsic character of the compound
• Qualitative; this compound causes something
• Quantitavie; NOAL and LOAEL
Exposure; quantitative (hoeveelheid) measure for the presence of hazard
NOAEL; no observable adverse effect level
LOAEL; lowest observable adverse effect level
The risk dose is between NOAEL and LOAEL
CES; critical effect size
CED; critical effect dose = BDM; benchmark dose
BMDL; benchmark dose lower confidence bound
ADI; acceptable daily intake → acceptable intake of food or
drinking water what is NOT contaminated
TDI; tolerable daily intake → acceptable intake of food or
drinking water what is contaminated. NOAEL/UF or BMDL/UF or MPRL
UF; uncertainty factor (onzekerheidsfactor), if data is lacking to provide a scientifically
evaluation.
• Interspecies; from test animal to human
• Intraspecies; from average person to most sensitive person
• Shortcoming within the dataset
What is risk?
Paracelsus; Everything is toxic, it depends on the dose.
Forward problem; what is the risk (response) of a given
exposure?
Backward problem; which exposure corresponds to an
acceptable risk (response?
Risk = hazard (gevaar) * exposure (blootstelling)
Risk is the probability that a negative effect will occur.
Risk assessment is just a part of the risk management.
Comparison of risks by toxic compounds to other risk factors
DALY (disability adjusted life years); express risks in terms of lost life years
DALY=YYL (years of life lost) * YLD (years lost to disability)
YYL; years lost due to premature death; n (aantal mensen) * standard life
expectation in year of death (verschil tussen leeftijd doodgaan en life
expectation)
YLD; years lived with disease; n (aantal mensen) * handicap weight * duration
diseases till recovery or death
Hoe can critical exposures be determined?
Hazard; Intrinsic character of the compound
• Qualitative; this compound causes something
• Quantitavie; NOAL and LOAEL
Exposure; quantitative (hoeveelheid) measure for the presence of hazard
NOAEL; no observable adverse effect level
LOAEL; lowest observable adverse effect level
The risk dose is between NOAEL and LOAEL
CES; critical effect size
CED; critical effect dose = BDM; benchmark dose
BMDL; benchmark dose lower confidence bound
ADI; acceptable daily intake → acceptable intake of food or
drinking water what is NOT contaminated
TDI; tolerable daily intake → acceptable intake of food or
drinking water what is contaminated. NOAEL/UF or BMDL/UF or MPRL
UF; uncertainty factor (onzekerheidsfactor), if data is lacking to provide a scientifically
evaluation.
• Interspecies; from test animal to human
• Intraspecies; from average person to most sensitive person
• Shortcoming within the dataset
