Table 2.

Summary of PFOA concentrations (ng/g ww or ng/ml) in mouse and human bone, human serum samples and in in vitro studies of mouse and human osteoblasts and osteoclasts.

Study	n	% Detect	Mean	Median	Min-max	NOAEL	LOAEL
Chemical analyses
Mouse bones
Pooled femurs and tibias, controls15	2a	100	0.69	0.69	0.64–0.73	—	—
Pooled femurs and tibias, exposed15	2a	100	3.35	3.35	3.0–3.7	—	3.0b
Human bone bank (current study)
Trabecular bone	19	63	0.15	0.18	<LOQ-0.38	—	—
Bone marrow	19	100	0.44	0.34	<LOQ-1.5	—	—
Other studies
Spanish population, rib bone12	20	55	60.2	20.9	<LOQ-234	—	—
Swedish women, nursing, serum41	413	—	1.71	—	—	—	—
US Firefighters, serum42	12	100	7.0	6.0	2–12	—	—
US Population, serum43	2094	99.7	3.9	4.0	<LOQ-4.3	—	—
Finnish Firefighters, serum44	8	100	3.2	2.94	1.61–4.85	—	—
Swedish population, serum45	579	100	2.8	—	0.33–15	—	—
In vitro –studies
Cells, mouse15
Osteoblasts	—	—	—	—	—	41.4	414.1c
Osteoclasts	—	—	—	—	—	41.4	414.1d
Cells, human (present study)
Osteoblasts	—	—	—	—	—	82 814e	—
Osteoclasts, PB	—	—	—	—	—	—	41.4f
Osteoclasts, MSCs	—	—	—	—	—	41.4	414.1g

Data from the present study and the indicated references. NOAEL = no-observed adverse effect level, LOAEL = lowest observed adverse effect level.

^aPooled samples from 20 animals, n = 5 in each group.

^bIncreased femoral periosteal and medullary area, decreased cortical mineral density of tibias.

^cIncreased osteocalcin expression.

^dIncreased resorption area.

^eNo significant effects.

^fIncreased number of osteoclasts.

^gIncreased resorption area.