Table 2.

Calculated toxic units (TUs) based on IC₂₀ values in the FITC-T4 in vitro assay (Hamers et al. 2020) and concentrations (nM) determined in this study and a previous study (Norrgran Engdahl et al. 2017)

Substance	IC20a (nM)	Cmedian (nM)	Cmax (nM)	TUmedian	TUmax
PFHxS	136	1.2	5.3	0.01	0.04
PFOS	82	4.6	10	0.06	0.12
PFHpA	299	1.6	12	0.01	0.04
PFOA	491	2.8	35	0.01	0.07
PFNA	361	0.47	2.2	0.001	0.01
PFDA	1710	0.84	2.9	0.0005	0.002
PFUnDA	1010	0.87	3.0	0.0009	0.003
Pentachlorophenol b	17	0.41	4.2	0.02	0.24
CB153b	77	0.17	1.5	0.002	0.02
2,4,6-TBPb	8.9	0.44	1.1	0.05	0.13
6OH-BDE47b	31	0.5	3.4	0.02	0.11
BDE47b	210	0.04	0.26	0.0002	0.001
BDE99b	73	0.06	0.61	0.0008	0.008
∑TUs				0.17	0.79

^aHamers et al. (2020)

^bNorrgran Engdahl et al. (2017)