Table 3.

Odds ratios (OR) and 95% confidence intervals (CI) for the association between an interquartile range increase in PM_2.5 and childhood cancer risk, per pregnancy period.

	First Trimester (IQR: 2.50) a					2nd Trimester (IQR: 2.46) b				Third Trimester (IQR: 2.50) c				Full Pregnancy (IQR: 1.88) d
Cancer type	N, 5069	OR	95% CI		FDR P	OR	95% CI		FDR P	OR	95% CI		FDR P	OR	95% CI		FDR P
All cancer combined	1236	0.96	0.88	1.04	0.78	0.93	0.86	1.02	0.63	1.04	0.95	1.13	0.77	0.95	0.87	1.04	0.62
Lymphoid leukemias	297	0.99	0.85	1.16	0.98	0.92	0.79	1.09	0.75	1.17	1.01	1.37	0.27	1.03	0.87	1.23	0.94
Mature B-cell leukemias	263	1.01	0.86	1.20	0.98	0.96	0.81	1.14	0.86	1.20	1.02	1.41	0.27	1.07	0.90	1.28	0.69
Mature T-cell leukemias	20	0.91	0.50	1.65	0.98	1.06	0.57	1.97	0.95	1.64	0.97	2.76	0.33	1.34	0.70	2.56	0.62
<1 year	17	0.62	0.30	1.27	0.68	0.57	0.27	1.17	0.63	1.20	0.64	2.25	0.83	0.65	0.33	1.29	0.62
1–5 years	230	1.05	0.88	1.25	0.97	0.93	0.78	1.12	0.75	1.13	0.95	1.34	0.45	1.04	0.86	1.26	0.83
Acute myeloid leukemias	58	0.95	0.66	1.37	0.98	0.84	0.58	1.23	0.75	1.14	0.81	1.62	0.80	0.98	0.67	1.43	0.95
Other leukemias e	32	0.76	0.47	1.23	0.78	0.80	0.49	1.29	0.75	1.01	0.64	1.59	0.98	0.77	0.48	1.23	0.62
Hodgkin lymphomas	16	0.98	0.53	1.83	0.98	2.60	1.52	4.45	0.01	0.89	0.45	1.77	0.88	1.92	0.95	3.87	0.43
Non-Hodgkin lymphomas	27	0.51	0.29	0.90	0.17	0.80	0.47	1.34	0.75	0.67	0.40	1.14	0.45	0.62	0.38	1.00	0.43
Burkitt lymphoma	18	1.93	1.13	3.30	0.17	1.24	0.68	2.28	0.76	1.38	0.74	2.54	0.70	1.72	0.86	3.44	0.62
Miscellaneous lymphoreticular neoplasms	52	1.43	1.01	2.01	0.27	1.05	0.72	1.51	0.95	1.09	0.76	1.58	0.83	1.32	0.86	2.01	0.62
Ependymomas	40	1.23	0.82	1.84	0.78	0.83	0.53	1.30	0.75	0.95	0.60	1.49	0.89	0.97	0.62	1.51	0.95
Astrocytomas	130	0.74	0.58	0.95	0.17	1.01	0.80	1.28	0.95	0.84	0.66	1.07	0.45	0.80	0.63	1.01	0.43
Medulloblastomas	36	0.67	0.42	1.08	0.42	0.90	0.57	1.43	0.87	0.86	0.54	1.36	0.81	0.73	0.47	1.13	0.62
Other intracranial and intraspinal embryonal f	19	1.13	0.61	2.06	0.98	0.66	0.33	1.31	0.65	1.90	1.07	3.37	0.27	1.17	0.59	2.32	0.86
Other CNS cancer types g	57	1.01	0.72	1.41	0.98	0.79	0.55	1.13	0.63	1.30	0.94	1.79	0.45	0.96	0.67	1.37	0.95
Neuroblastoma and other peripheral nervous cell tumors	148	0.93	0.75	1.16	0.97	0.79	0.63	0.99	0.48	0.79	0.63	0.99	0.27	0.76	0.61	0.96	0.43
Retinoblastoma	43	1.10	0.73	1.65	0.98	1.02	0.67	1.55	0.95	1.21	0.80	1.82	0.75	1.17	0.74	1.84	0.83
Renal tumors	107	0.93	0.72	1.20	0.97	0.94	0.72	1.21	0.86	1.07	0.83	1.38	0.83	0.97	0.75	1.27	0.95
Hepatic tumors	24	1.18	0.72	1.94	0.97	0.99	0.58	1.68	0.97	0.98	0.57	1.67	0.97	1.14	0.66	1.95	0.86
Malignant bone tumors	19	1.29	0.75	2.22	0.81	1.44	0.82	2.51	0.63	0.93	0.50	1.73	0.89	1.39	0.75	2.59	0.62
Soft tissue and other extraosseous sarcomas	54	0.97	0.67	1.41	0.98	0.77	0.52	1.15	0.63	1.28	0.89	1.84	0.45	0.99	0.68	1.46	0.97
Germ cell tumors, trophoblastic tumors and neoplasms of gonads	40	0.67	0.43	1.05	0.41	1.03	0.69	1.55	0.95	1.09	0.73	1.61	0.85	0.85	0.55	1.32	0.83
Other malignant epithelial neoplasms and malignant melanomas	19	0.98	0.54	1.76	0.98	1.50	0.82	2.73	0.63	0.78	0.39	1.56	0.80	1.16	0.62	2.17	0.86

Abbreviation: PM_2.5: Particulate matter <2.5 mg/m³; FDR: False Discovery Rate. 1st Trimester included 1st, 2nd and 3rd month of a pregnancy; 2nd Trimester included 4th, 5th and 6th month of a pregnancy; 3rd Trimester included 7th, 8th, 9th month of a pregnancy. Bold values indicated P-value less than 0.05.

^aAdjusted for trimester 1 PM2.5 for each control IQR increase from trimester 1, maternal age at delivery, maternal race/ethnicity, maternal education, child sex, year of birth, trimester 2 PM2.5 (high/low), trimester 3 PM2.5 (high/low).

^bAdjusted for trimester 2 PM2.5 for each control IQR increase from trimester 2, maternal age at delivery, maternal race/ethnicity, maternal education, child sex, year of birth, trimester 1 PM2.5 (high/low), trimester 3 PM2.5 (high/low).

^cAdjusted for trimester 3 PM2.5 for each control IQR increase from trimester 3, maternal age at delivery, maternal race/ethnicity, maternal education, child sex, year of birth, trimester 1 PM2.5 (high/low), trimester 2 PM2.5 (high/low).

^dAdjusted for PM2.5 for each control IQR increase from full pregnancy, maternal age at delivery, maternal race/ethnicity, maternal education, child sex, year of birth.

^eChronic myeloproliferative diseases, Myelodysplastic syndrome, Unspecified and other specified leukemias.

^fPrimitive neuroectodermal tumor (PNET), Medulloepithelioma, Atypical teratoid/rhabdoid tumor.

^gOther gliomas, Other specified intracranial and intraspinal neoplasms, Unspecified intracranial and intraspinal neoplasms.