19085-1701857-UL_Prop_65_Test_Results_2019

Released by UL Environment
Date Prepared:
February 11, 2019
Report #:
1000339735-1162663EA
©2019 UL LLC
CA Prop 65 Exposure Assessment Page 10 | 15
Table 3. Lifetime Average Daily Doses (LADDs)
Exposure
Scenario
1,4 Dioxane LADD
(µg/day)
Acetaldehyde LADD
(µg/day)
Cumene LADD
(µg/day)
Private Office 0.4 2.0 1.0
School Classroom 0.04 0.2 0.1
Home Residence 0.2 1.1 0.5
NSRL 30
1
90
1
3.7
2
LADDs reported in bold exceed NSRL
1
OEHHA NSRL
2
Calculated provisional NSRL following OEHHA guidance (see Appendix A)
CONCLUSIONS
There always is uncertainty regarding the estimates in an exposure assessment. By
necessity, assumptions and extrapolations are required to fill areas of missing and limited
data. The use of conservative product assumptions and exposure parameters, however,
ensures that the calculated LADDs overestimate actual exposures that occur during
product usage. Use of conservative exposure assumptions and exposure parameters for
the Execumat Chair Mats used within a private office, school classroom, and home
residence results in estimated 1,4 dioxane LADDs of 0.4, 0.04 and 0.2 µg/day;
acetaldehyde LADDs of 2.0, 0.2, 1.1 µg/day, and cumene LADDs of 1.0, 0.1, 0.5 µg/day,
respectively. These calculated LADDs are less than the established safe harbor value for
1,4 dioxane (NSRL 30 µg/day) and acetaldehyde (NSRL 90 µg/day) as well as the
provisional NSRL for cumene of 3.7 µg/day (see Appendix A).
Actual 1,4 dioxane, acetaldehyde and cumene exposures associated with the use of the
Execumat Chair Mats within an indoor environment will be lower than the LADD values
calculated within this assessment. For example, it is well documented that VOC emissions
from consumer materials decrease over the lifetime of the product. The estimated
acetaldehyde and cumene emission rates used herein occur early in the products’ lifetime
and are assumed to remain constant over a 25-year exposure period. In addition 1,4
dioxane emissions were only present above quantification level during the first 72 hours of
product emission testing but have been assumed to continue at the calculated emission
rate over the 25-year product life. Continued decay and resulting reduction of emissions
over the product life was not considered in this evaluation.
In addition, the minimum air exchange rates used within the private office, school
classroom and home residence are all based on the ASHRAE minimum ventilation