318
G Case Study Solutions
As the risk quotients are much less than one, there is likely not a risk posed to
these species as indicated by the modeled environmental concentration value in this
particular scenario and considering just these three toxicological studies. This result
clearly represents a very simplified calculation based on limited data and cannot be
used to assess the actual environmental safety of the product.
Human Toxicity: Occupational
Considering the set AOEL of 0.03 mg kg
−1
bw d −1 according to EFSA (EFSA, 2014),
the calculated occupational exposure to operators without PPE is greater than 500%
of the AOEL, and with PPE it is 52% of the AOEL. There is clearly a risk present
when PPE is not used, and no risk is expected to be posed when PPE is worn.
EFSA writes that they arrived at this AOEL value (and also at the ADI value)
“based on the LOAEL of 10 mg/kg bw per day from the developmental toxicity study
in rat, applying an uncertainty factor (UF) of 300 [referred to in this book as an
assessment factor], 100 standard factor plus additional factor of 3 to account for the
LOAEL basis” (EFSA, 2014).
Human Toxicity: Dietary
The highest calculated PDI for any population group and country (see Table G.10)
was calculated as 0.00125 mg kg
−1
bw d −1 . This is a factor of 24 below the set ADI of
0.03 mg/kg (EFSA, 2014), indicating a large margin of safety for dietary consumer
risk.
G.4.5 Step 5: Risk Management
(a) Of the three areas investigated, the only risk that was found to be not acceptable
was the occupational exposure to ASM for workers without PPE.
(b) PPE should always be properly worn when spraying Bion ® .
(c) This case study was clearly limited in scope and made use of just a very small
subset of data and available modeling tools to examine specific risks. Some
of the clear limitations and uncertainties for each of the investigated areas
include:
• Risk to the environment: (1) The small-world model is a simplified level
III model making use of just a small set of physicochemical properties
to describe ASM and the environment it could be applied within. Further,
detailed information regarding the application and actual environmental
conditions could be used in a more sophisticated model to estimate the
PEC. Field studies and environmental monitoring would, of course, be more
accurate. (2) Only a single toxicological study for just one aquatic species
was considered in defining the PNEC. Many more toxicological studies, as
well as a rigorous approach to applying a best assessment factor, are needed
in order to define a more reliable PNEC.
G Case Study Solutions
As the risk quotients are much less than one, there is likely not a risk posed to
these species as indicated by the modeled environmental concentration value in this
particular scenario and considering just these three toxicological studies. This result
clearly represents a very simplified calculation based on limited data and cannot be
used to assess the actual environmental safety of the product.
Human Toxicity: Occupational
Considering the set AOEL of 0.03 mg kg
−1
bw d −1 according to EFSA (EFSA, 2014),
the calculated occupational exposure to operators without PPE is greater than 500%
of the AOEL, and with PPE it is 52% of the AOEL. There is clearly a risk present
when PPE is not used, and no risk is expected to be posed when PPE is worn.
EFSA writes that they arrived at this AOEL value (and also at the ADI value)
“based on the LOAEL of 10 mg/kg bw per day from the developmental toxicity study
in rat, applying an uncertainty factor (UF) of 300 [referred to in this book as an
assessment factor], 100 standard factor plus additional factor of 3 to account for the
LOAEL basis” (EFSA, 2014).
Human Toxicity: Dietary
The highest calculated PDI for any population group and country (see Table G.10)
was calculated as 0.00125 mg kg
−1
bw d −1 . This is a factor of 24 below the set ADI of
0.03 mg/kg (EFSA, 2014), indicating a large margin of safety for dietary consumer
risk.
G.4.5 Step 5: Risk Management
(a) Of the three areas investigated, the only risk that was found to be not acceptable
was the occupational exposure to ASM for workers without PPE.
(b) PPE should always be properly worn when spraying Bion ® .
(c) This case study was clearly limited in scope and made use of just a very small
subset of data and available modeling tools to examine specific risks. Some
of the clear limitations and uncertainties for each of the investigated areas
include:
• Risk to the environment: (1) The small-world model is a simplified level
III model making use of just a small set of physicochemical properties
to describe ASM and the environment it could be applied within. Further,
detailed information regarding the application and actual environmental
conditions could be used in a more sophisticated model to estimate the
PEC. Field studies and environmental monitoring would, of course, be more
accurate. (2) Only a single toxicological study for just one aquatic species
was considered in defining the PNEC. Many more toxicological studies, as
well as a rigorous approach to applying a best assessment factor, are needed
in order to define a more reliable PNEC.