Chapter 3: PPPs and human health

Question 1

Define risk assessment?

Answer 1

• a comprehensive evaluation process following scientific principles carried out in cooperation with experts

Question 2

What is risk?

Answer 2

Risk= f(x) hazard (toxicity) x exposure

• Risk: The potential for injury to take place
• Hazard (toxicity): The capacity of a pesticide to cause injury
• Exposure: The amount of pesticide entering or contacting the body

Question 3

What is the difference between acute and chronic effects?

Answer 3

• Toxicological testing evaluates whether short-term exposure to a plant protection product will produce-
  1. acute effects (e.g., eye and skin irritation, death)

and whether long-term, continual exposure will cause

2.chronic effects (e.g., impaired liver function, reproductive abnormalities, cancer)

Question 4

Define duration and magnitude of exposure?

Answer 4

• The duration and magnitude of exposure determine the severity of the adverse effect

1. Duration: increment of time during which exposure to the dose occurs
2. Magnitude of exposure: size and number of doses received

Question 5

Know the concept of dose and response? Draw the dose response curve? What does the slope of the curve tell us? Interpretation of dose response relationships? Explain the different values like LD50 etc. – Will be a question!!

Answer 5

1. The toxicity of a chemical substance is determined by quantifying the response of laboratory animals to a series of increasing doses
2. The relationship between the administered dose and animal response is graphically depicted as the dose- response curve
3. The higher the LD50 dose, the less acutely toxic the chemical substance
4. The threshold level is the lowest dose that produces a measurable response in the most sensitive animals (Between NOEL and LOEL)
5. The slope of the dose-response curve is of critical importance: a steep curve indicates only a slight difference between a nontoxic dose and a toxic dose

Question 6

Human risk assessment- Risk assessment is a multi step process. What are the steps?

Answer 6

1. Toxicity assessment: evaluation of intrinsic toxicity or hazard potential of the chemical
2. Exposure assessment: estimation of potential human exposure to the chemical
3. Risk characterization: evaluation of potential risk to humans

Question 7

Routes of exposure- and which route plays are more important role for the consumers and which one for the operators? Question!!!

Answer 7

Plant protection products may enter the human body through:

1. the skin (dermal exposure)
2. the mouth (oral exposure)
3. the lungs (respiratory exposure)

The site of exposure to the plant protection products impacts the rate of absorption into the bloodstream, as well as its distribution pattern

• General public exposure regards mainly residues in food and water (dietary exposure), but also residential exposure
• Occupational exposure occurs during manufacture, transport or use of plant protection products
• Skin, Oral, Lungs (respiratory) –> Operator rather skin

Question 8

Which are the factors that influence the dermal exposure? Question!!!

Answer 8

1. Different anatomical sites
2. Warm and moist areas with increased blood vessels
3. Skin condition such as cuts, abrasions and rashes
4. Type of plant protection product formulation

Question 9

How does the dietary exposure estimation work?

Answer 9

1. Main source of exposure for the general public
2. Dietary exposure is a function of the type and amount of food consumed and the residues of the plant protection product in or on that food
3. Two types of dietary exposure are generally considered: chronic and acute

Question 10

How is the operator exposure estimation done?

Answer 10

1. Dosimetry estimates (patches on the overalls)
2. At the end of exposure, patches are removed and the amount of plant protection product is analyzed
3. Biological monitoring via analysis of urine, blood, and/or exhalation for the PPP and/or its metabolites

Question 11

What are the toxicological thresholds? Question!!

Answer 11

Acceptable Daily Intake (ADI): Threshold for lifespan dietary exposure (= chronic RfD)

Acute Reference Dose (ARfD): Threshold set for compounds that pose risk for effects following single or short term dietary exposure, e.g. acute or subacute effects

Acceptable Operator Exposure Levels (AOEL): Threshold for repeated non dietary exposure