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BACKGROUNDThe advancement of natural gas (NG) extraction across the United States (U.S.) raises concern for potential exposure to hazardous air pollutants (HAPs). Benzene, a HAP and a primary chemical of concern due to its classification as a known human carcinogen, is present in petroleum-rich geologic formations and is formed during the combustion of bypass NG. It is a component in solvents, paraffin breakers, and fuels used in NG extraction and processing (E&P).OBJECTIVESThe objectives of this study are to confirm the presence of benzene and benzene-related compounds (benzene[s]) in residential areas, where unconventional shale E&P is occurring, and to determine if benzene[s] exists in elevated atmospheric concentrations when compared to national background levels.METHODSAmbient air sampling was conducted in six counties in the Dallas/Fort Worth Metroplex with passive samples collected in evacuated 6-L Summa canisters. Samples were analyzed by gas chromatography/mass spectrometry, with sampling performed at variable distances from the facility fence line.RESULTSElevated concentrations of benzene[s] in the atmosphere were identified when compared to U.S. Environmental Protection Agency’s Urban Air Toxics Monitoring Program. The 24-hour benzene concentrations ranged from 0.6 parts per billion by volume (ppbv) to 592 ppbv, with 1-hour concentrations from 2.94 ppbv to 2,900.20 ppbv.CONCLUSIONBenzene is a known human carcinogen capable of multisystem health effects. Exposure to benzene is correlated with bone marrow and blood-forming organ damage and immune system depression. Sensitive populations (children, pregnant women, elderly, immunocompromised) and occupational workers are at increased risk for adverse health effects from elevated atmospheric levels of benzene[s] in residential areas with unconventional shale E&P.

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Background Maternal migraine has been linked to adverse birth outcomes including low birth weight and preterm birth, as well as congenital anomalies in offspring. It has been speculated that this may be due to the use of medications in pregnancy, but lifestyle, genetic, hormonal, and neurochemical factors could also play a role. There is evidence for varying cancer incidences among adults with migraine. Here, we utilized data from national registries in Denmark to examine associations between maternal diagnoses of migraine and risk for cancer in offspring. Methods We linked several national registries in Denmark to identify cases from the Cancer Registry among children less than 20 years (diagnoses 1996–2016) and controls from the Central Population Register, matched to cases by birth year and sex (25:1 matching rate). Migraine diagnoses were identified from the National Patient Register using International Classification of Diseases, versions 8 and 10 codes and migraine‐specific acute or prophylactic treatment recorded in the National Pharmaceutical Register. We used logistic regression to estimate the risk of childhood cancers associated with maternal migraine. Results Maternal migraine was positively associated with risk for non‐Hodgkin lymphoma (odds ratio [OR] = 1.70, 95% confidence interval [CI]: 1.01–2.86), central nervous system tumors ([OR = 1.31, 95% CI: 1.02–1.68], particularly glioma [OR = 1.64, 95% CI: 1.12–2.40]), neuroblastoma (OR = 1.75, 95% CI: 1.00–3.08), and osteosarcoma (OR = 2.60, 95% CI: 1.18–5.76). Conclusions Associations with maternal migraine were observed for several childhood cancers, including neuronal tumors. Our findings raise questions about the role of lifestyle factors, sex hormones, genetic, and neurochemical factors in the relationship between migraine and childhood cancers.

Background Childhood cancer may be related to maternal health in pregnancy. Maternal anemia is a common condition in pregnancy, especially in low‐income countries, but the association between maternal anemia and childhood cancer has not been widely studied. Objective To examine the potential relation between maternal anemia during pregnancy and childhood cancers in a population‐based cohort study in Taiwan. Methods We examined the relationship between maternal anemia and childhood cancer in Taiwan (N = 2160 cancer cases, 2,076,877 noncases). Cases were taken from the National Cancer Registry, and noncases were selected from birth records. Using national health registries, we obtained maternal anemia diagnoses. We estimated the risks for childhood cancers using Cox proportional hazard analysis. Results There was an increased risk of cancers in children born to mothers with nutritional anemia (hazard ratio (HR): 1.32, 95% CI 0.99, 1.76). Iron deficiency anemia (HR: 1.30, 95% CI 0.97–1.75) carried an increased risk, while non‐nutritional anemias were not associated with childhood cancer risk. Conclusion Our results provide additional support for screening for anemia during pregnancy. Adequate nutrition and vitamin supplementation may help to prevent some childhood cancer.