Background: Night shift work has been classified by the International Agency for Research on Cancer as a probable carcinogen in humans. Several studies have assessed night shift work in relation to breast cancer risk, with inconsistent results.Methods: In the prospective Sister Study cohort, current and past occupational history was collected for 48,451 participants. We used Cox proportional hazards models to estimate adjusted HRs and 95% confidence intervals (CI) for the association between baseline work schedule characteristics and incident breast cancer.Results: During follow-up (mean ¼ 9.1 years), 3,191 incident cases were diagnosed. We observed little to no increase in risk associated with work schedule characteristics (ever working rotating shifts: HR ¼ 1.04, 95% CI, 0.91-1.20; ever working rotating night shifts: HR ¼ 1.08, 95% CI, 0.92-1.27; ever working at night: HR ¼ 1.01, 95% CI, 0.94-1.10; and ever working irregular hours: HR ¼ 0.98, 95% CI, 0.91-1.06). Although short-term night work (>0 to 5 years vs. never: HR ¼ 1.12; 95% CI, 1.00-1.26) and rotating shift work at night (>0 to 5 years vs. never: HR ¼ 1.30; 95% CI, 1.05-1.61) were associated with increased breast cancer risk, working nights for more than 5 years was not associated with risk.Conclusions: Overall, we observed little evidence that rotating shift work or work at night was associated with a higher risk of breast cancer, except possibly among those who participated in such work for short durations of time.Impact: This study indicates that if night shift work is associated with breast cancer, the increase in risk is small.

Phthalates are ubiquitous chemical compounds, and two-di-ethyl phthalate (DEP) and di-isobutyl phthalate (DiBP)-are not currently regulated by the U.S. Congress or the European Union. While many reviews of phthalates have been published, none have examined bone health, inflammation, or oxidative stress; anogenital distance was most recently reviewed in 2014. The objective of this paper is to determine if an association exists between mono-ethyl phthalate (MEP) or mono-isobutyl phthalate (MiBP), metabolites of DEP and DiBP, respectively, and the four outcomes indicated above. We conducted a literature search of PubMed through December 2017 and included 29 observational epidemiologic studies published in English that assessed MEP and/or MiBP in relation to one of the above four health outcomes in humans. Two authors rated each paper using a modified Downs and Black (DB) assessment tool; a third author settled score disagreements. A single author extracted information related to the study population, exposure and outcome assessment, covariates, and significant results from each article. Ten studies were identified on anogenital distance, four on bone health, five on inflammation, and thirteen on oxidative stress. Score percentages (total points given out of total possible points) were calculated for each study. The current research suggests a positive association between MiBP and two measures of oxidative stress, 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane. MEP is potentially associated with 8-OHdG as well, although the evidence is limited by fewer highquality studies. There does not appear to be an association between anogenital distance and MEP or MiBP, and it is unclear if relationships exist between these phthalate metabolites and bone health and inflammation. Given the role that oxidative stress plays in a number of diseases and the ubiquity of MEP and MiBP, it is important that individuals be aware of potential sources of exposure to these chemicals.

Background: The aim of this systematic review was to evaluate medical conditions and modifiable risk factors for myelodysplastic syndromes (MDS) using the 2001 or 2008 World Health Organization (WHO) diagnostic criteria. Methods: PubMed, MEDLINE, and Scopus databases were searched for studies published between January 2001 and August 2017. Study characteristics and findings were abstracted for each article. Results: Thirteen articles (4 cohort, 9 case-control) met the inclusion criteria. Smoking and alcohol use were each evaluated as potential MDS risk factors in four studies. Body mass index and anemia were each evaluated in two studies. Other potential risk factors evaluated in single studies included physical activity, dietary intake (tea, isoflavones, meat, fruit, or vegetables), history of allergies, autoimmune disorders and community-acquired infections, and use of antituberculosis drugs, traditional Chinese medicines, or hair dyes. Conclusions: Higher BMI, smoking, a history of autoimmune disorders, community-acquired infections, history of anemia, and use of antituberculosis drugs were associated with higher risk of MDS. Vigorous physical activity and tea and dietary isoflavone intake were associated with lower MDS risk. These findings suggest no association between the other factors and risk of MDS. Impact: Research on risk factors for MDS is limited, and further research in larger studies is needed.