A case-control study of exposure to organophosphate flame retardants and risk of thyroid cancer in women

BMC Cancer

Table 4 Odds ratios and 95% confidence intervals for the association of urinary concentrations of organophosphate flame retardants (ng/ml; specific gravity-corrected) and microcarcinomas and larger tumor papillary thyroid cancer in Connecticut women

	Microcarcinomas (Tumor Diameter ≤ 1 cm)					Larger Tumor Size (Tumor Diameter > 1 cm)
Organophosphate Flame Retardant (ng/ml)	Cases	Controls	OR^a	95% CI	p- trend	Cases	Controls	OR^a	95% CI	p- trend
BCIPP
< MDL	32	50	1			28	50	1
≥ MDL - 0.45	9	25	0.52	(0.18, 1.38)	0.06	16	25	0.99	(0.38, 2.56)	0.31
> 0.45	6	25	0.38	(0.12, 1.09)	0.06	7	25	0.51	(0.15, 1.56)	0.31
Continuous^b	47	100	0.84	(0.69, 1.03)		51	100	0.94	(0.77, 1.14)
DPHP
< 0.59	17	33	1			16	33	1
0.59–1.28	15	33	0.87	(0.33, 2.29)	0.61	18	33	0.94	(0.33, 2.67)	0.57
> 1.28	15	34	0.78	(0.29, 2.05)	0.61	17	34	1.32	(0.49, 3.64)	0.57
Continuous^b	47	100	0.86	(0.56, 1.26)		51	100	1.08	(0.76, 1.55)
BDCIPP
< 0.37	15	33	1			14	33	1
0.37–0.96	15	33	0.76	(0.28, 2.03)	0.90	18	33	1.02	(0.36, 2.86)	0.49
> 0.85	17	34	1.03	(0.41, 2.65)	0.90	19	34	1.43	(0.51, 4.08)	0.49
Continuous^b	47	100	0.98	(0.74, 1.31)		51	100	1.12	(0.84, 1.51)
IPDPP
< 1.60	17	33	1			13	33	1
1.60–3.56	12	33	0.79	(0.30, 2.08)	0.99	16	33	1.00	(0.35, 2.84)	0.52
> 3.56	18	34	1.01	(0.39, 2.55)	0.99	22	34	1.37	(0.50, 3.83)	0.52
Continuous^b	47	100	1.06	(0.70, 1.60)		51	100	0.98	(0.62, 1.54)
BCIPHIPP
< 0.12	18	33	1			20	33	1
0.12–0.32	18	33	1.06	(0.44, 2.57)	0.25	15	33	0.81	(031, 2.10)	0.27
> 0.32	11	34	0.54	(0.19, 1.45)	0.25	16	34	0.57	(0.21, 1.52)	0.27
Continuous^b	47	100	0.79	(0.57, 1.06)		51	100	0.77	(0.59, 1.00)
Summed PFR
< 4.10	20	34	1			14	34	1
4.10–7.95	12	33	0.65	(0.25, 1.66)		17	33	1.37	(0.50, 3.83)	0.55
> 7.95	15	33	0.75	(0.29, 1.93)	0.53	20	33	1.37	(0.50, 3.79)	0.55
Continuous^b	47	100	0.77	(0.47, 1.22)		51	100	1.02	(0.66, 1.57)

bis(1-chloro-2-propyl) 1-hydroxy-2-propyl phosphate (BCIPHIPP), bis(1-chloro-2-propyl) phosphate (BCPP), diphenyl phosphate (DPP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), isopropyl-phenyl phenyl phosphate (IP-DPP), and tert-butyl phenyl phenyl phosphate (tb-PPP), odds ratio (OR), 95% confidence interval (95%CI), PFR (organophosphate flame retardant)
^aAdjusted for age, BMI, education level, family history of thyroid cancer, previous benign thyroid disease, and alcohol consumption
^bBased on log-transformed PFR concentrations; odds ratio calculated for each 1og of 1 ng/ml

ISSN: 1471-2407