BACKGROUND: At high medicinal doses perchlorate is known to decrease the production of thyroid hormone, a critical factor for fetal development. In a large and uniquely exposed cohort of pregnant women, we recently identified associations between environmental perchlorate exposures and decreased maternal thyroid hormone during pregnancy. Here, we investigate whether perchlorate might be associated with birthweight or preterm birth in the offspring of these women. METHODS: Maternal urinary perchlorate, serum thyroid hormone concentrations, birthweight, gestational age, and urinary nitrate, thiocyanate, and iodide were collected in 1957 mother-infant pairs from San Diego County during 2000-2003, a period when the county's water supply was contaminated with perchlorate. Associations between perchlorate exposure and birth outcomes were examined using linear and logistic regression analyses adjusted for maternal age, weight, race/ethnicity, and other factors. RESULTS: Perchlorate was not associated with birth outcomes in the overall population. However, in analyses confined to male infants, log10 maternal perchlorate concentrations were associated with increasing birthweight (beta=143.1gm, p=0.01), especially among preterm births (beta=829.1g, p<0.001). Perchlorate was associated with male preterm births ≥2500g (odds ratio=3.03, 95% confidence interval=1.09-8.40, p-trend=0.03). Similar associations were not seen in females. CONCLUSIONS: This is the first study to identify associations between perchlorate and increasing birthweight. Further research is needed to explore the differences we identified related to infant sex, preterm birth, and other factors. Given that perchlorate exposure is ubiquitous, and that long-term impacts can follow altered birth outcomes, future research on perchlorate could have widespread public health importance.

BACKGROUND: Findings from national surveys suggest that everyone in the United States is exposed to perchlorate. At high doses, perchlorate, thiocyanate, and nitrate inhibit iodide uptake into the thyroid and decrease thyroid hormone production. Small changes in thyroid hormones during pregnancy, including changes within normal reference ranges, have been linked to cognitive function declines in the offspring. OBJECTIVES: We evaluated the potential effects of low environmental exposures to perchlorate on thyroid function. METHODS: Serum thyroid hormones and anti-thyroid antibodies and urinary perchlorate, thiocyanate, nitrate, and iodide concentrations were measured in 1,880 pregnant women from San Diego County, California, during 2000-2003, a period when much of the area's water supply was contaminated from an industrial plant with perchlorate at levels near the 2007 California regulatory standard of 6 μg/L. Linear regression was used to evaluate associations between urinary perchlorate and serum thyroid hormone concentrations in models adjusted for urinary creatinine and thiocyanate, maternal age and education, ethnicity, and gestational age at serum collection. RESULTS: The median urinary perchlorate concentration was 6.5 μg/L, about two times higher than in the general U.S. POPULATION: Adjusted associations were identified between increasing log10 perchlorate and decreasing total thyroxine (T4) [regression coefficient (β) = -0.70; 95% CI: -1.06, -0.34], decreasing free thyroxine (fT4) (β = -0.053; 95% CI: -0.092, -0.013), and increasing log10 thyroid-stimulating hormone (β = 0.071; 95% CI: 0.008, 0.133). CONCLUSIONS: These results suggest that environmental perchlorate exposures may affect thyroid hormone production during pregnancy. This could have implications for public health given widespread perchlorate exposure and the importance of thyroid hormone in fetal neurodevelopment. CITATION: Steinmaus C, Pearl M, Kharrazi M, Blount BC, Miller MD, Pearce EN, Valentin-Blasini L, DeLorenze G, Hoofnagle AN, Liaw J. 2016. Thyroid hormones and moderate exposure to perchlorate during pregnancy in women in Southern California. Environ Health Perspect 124:861-867; http://dx.doi.org/10.1289/ehp.1409614.

Narrative approaches and storytelling are emerging as powerful health promotion tools that can spark interest, increase understanding of determinants of health, and translate complex science. A Story of Health, a multimedia e-book with continuing education credits was designed to harness the power of storytelling to increase environmental health literacy. Health professionals are a key audience. They recognize that patients may be suffering from preventable illnesses of environmental origin but often feel ill-equipped to educate individuals and families about risks associated with common exposures. A Story of Health seeks to fill this gap and help readers develop the competencies they need in order to help patients make informed choices, reduce health risks, improve quality of life, and protect the environment. Americans rate nurses and medical doctors as having the highest honesty and ethical standards of all professions. These medical professionals can play a key role in changing patterns of patient behavior and influencing public policies. The e-book provides an easily accessible method of developing environmental health competency. The multimedia format with graphical interpretations allows for quick reviews of topics or for more in-depth analysis via links to additional resources. The CE evaluations have been overwhelmingly positive.

Tenofovir alafenamide (TAF) is a novel prodrug of tenofovir that efficiently delivers tenofovir-diphosphate to lymphoid cells following oral administration. We investigated if the combination of TAF and emtricitabine (FTC) could prevent simian HIV (SHIV) infection in macaques to determine the potential use of TAF for HIV pre-exposure prophylaxis (PrEP). Macaques were exposed rectally to SHIV once a week for up to 19 weeks and received saline or FTC/TAF 24h before and 2h after each virus inoculation. All 6 controls were infected, while the 6 PrEP-treated animals were protected from infection. Our results support the clinical investigation of FTC/TAF for PrEP.

The drinking water infrastructure in the United States is ageing; extreme weather events place additional stress on water systems that can lead to interruptions in the delivery of safe drinking water. We investigated the association between household exposures to water service problems and acute gastrointestinal illness (AGI) and acute respiratory illness (ARI) in Alabama communities that experienced a freeze-related community-wide water emergency. Following the water emergency, investigators conducted a household survey. Logistic regression models were used to estimate adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) for self-reported AGI and ARI by water exposures. AGI was higher in households that lost water service for 7 days (aPR 2.4, 95% CI 1.1-5.2) and experienced low water pressure for 7 days (aPR 3.6, 95% CI 1.4-9.0) compared to households that experienced normal service and pressure; prevalence of AGI increased with increasing duration of water service interruptions. Investments in the ageing drinking water infrastructure are needed to prevent future low-pressure events and to maintain uninterrupted access to the fundamental public health protection provided by safe water supplies. Households and communities need to increase their awareness of and preparedness for water emergencies to mitigate adverse health impacts.

Perchlorate, thiocyanate, and low iodine intake can all decrease iodide intake into the thyroid gland. This can reduce thyroid hormone production since iodide is a key component of thyroid hormone. Previous research has suggested that each of these factors alone may decrease thyroid hormone levels, but effect sizes are small. We hypothesized that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time. Using data from the 2007-2008 National Health and Nutrition Examination Survey, subjects were categorized into exposure groups based on their urinary perchlorate, iodine, and thiocyanate concentrations, and mean serum thyroxine concentrations were compared between groups. Subjects with high perchlorate (n=1939) had thyroxine concentrations that were 5.0% lower (mean difference=0.40mcg/dl, 95% confidence interval=0.14-0.65) than subjects with low perchlorate (n=2084). The individual effects of iodine and thiocyanate were even smaller. Subjects with high perchlorate, high thiocyanate, and low iodine combined (n=62) had thyroxine concentrations 12.9% lower (mean difference=1.07mcg/dl, 95% confidence interval=0.55-1.59) than subjects with low perchlorate, low thiocyanate, and adequate iodine (n=376). Potential confounders had little impact on results. Overall, these results suggest that concomitant exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production. This highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents.

Drug-resistant human immunodeficiency virus type 1 (HIV-1) minority variants increase the risk of virologic failure for first-line nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens. We performed a pooled analysis to evaluate the relationship between NNRTI-resistant minority variants and the likelihood and types of resistance mutations detected at virologic failure. In multivariable logistic regression analysis, higher NNRTI minority variant copy numbers, non-white race, and nevirapine use were associated with a higher risk of NNRTI resistance at virologic failure. Among participants on efavirenz, K103N was the most frequently observed resistance mutation at virologic failure regardless of the baseline minority variant. However, the presence of baseline Y181C minority variant was associated with a higher probability of Y181C detection after virologic failure. NNRTI regimen choice and preexisting NNRTI-resistant minority variants were both associated with the probability and type of resistance mutations detected after virologic failure.

CONTEXT: Presence of low-frequency, or minority, human immunodeficiency virus type 1 (HIV-1) drug resistance mutations may adversely affect response to antiretroviral treatment (ART), but evidence regarding the effects of such mutations on the effectiveness of first-line ART is conflicting. OBJECTIVE: To evaluate the association of preexisting drug-resistant HIV-1 minority variants with risk of first-line nonnucleoside reverse transcriptase inhibitor (NNRTI)-based antiretroviral virologic failure. DATA SOURCES: Systematic review of published and unpublished studies in PubMed (1966 through December 2010), EMBASE (1974 through December 2010), conference abstracts, and article references. Authors of all studies were contacted for detailed laboratory, ART, and adherence data. STUDY SELECTION AND DATA ABSTRACTION: Studies involving ART-naive participants initiating NNRTI-based regimens were included. Participants were included if all drugs in their ART regimen were fully active by standard HIV drug resistance testing. Cox proportional hazard models using pooled patient-level data were used to estimate the risk of virologic failure based on a Prentice weighted case-cohort analysis stratified by study. DATA SYNTHESIS: Individual data from 10 studies and 985 participants were available for the primary analysis. Low-frequency drug resistance mutations were detected in 187 participants, including 117 of 808 patients in the cohort studies. Low-frequency HIV-1 drug resistance mutations were associated with an increased risk of virologic failure (hazard ratio (HR], 2.3 [95% confidence interval {CI}, 1.7-3.3]; P < .001) after controlling for medication adherence, race/ethnicity, baseline CD4 cell count, and plasma HIV-1 RNA levels. Increased risk of virologic failure was most strongly associated with minority variants resistant to NNRTIs (HR, 2.6 [95% CI, 1.9-3.5]; P < .001). Among participants from the cohort studies, 35% of those with detectable minority variants experienced virologic failure compared with 15% of those without minority variants. The presence of minority variants was associated with 2.5 to 3 times the risk of virologic failure at either 95% or greater or less than 95% overall medication adherence. A dose-dependent increased risk of virologic failure was found in participants with a higher proportion or quantity of drug-resistant variants. CONCLUSION: In a pooled analysis, low-frequency HIV-1 drug resistance mutations, particularly involving NNRTI resistance, were significantly associated with a dose-dependent increased risk of virologic failure with first-line ART.

In The Lancet, Julia Brotherton and colleagues1 report a decrease in precancerous cervical lesions in girls younger than 18 years after population-wide human papillomavirus (HPV) vaccination in Victoria, Australia, in 2007. The study reports a 0·38% absolute decrease in the rates of histologically confirmed high-grade cervical lesions in these girls during the 2 years after HPV vaccine introduction compared with the 3 years before vaccine introduction.1 This ecological finding might be an early sentinel of the potential real-life effect of the vaccine on the main outcome in the clinical trials: cervical intraepithelial neoplasia of grade 2 or worse (CIN2+). However, these results should be viewed with caution, in view of the well-known limitations of ecological studies. For example, guidelines that emphasise less aggressive management of low-grade cytology, which were published 9 months before HPV vaccine introduction, could have contributed to the reported CIN2+ decrease.2 Health-care providers might also have screened and managed vaccinated patients less aggressively, especially girls younger than the recommended screening age of 18 years. With the 47·5% relative decrease in the incidence of high-grade cervical abnormalities recorded in girls younger than 18 years, a similar though smaller decrease would be expected in girls in the next oldest age group (those aged 18–20 years), who were likely to benefit from the vaccine and in whom vaccine coverage was high. However, no decrease was observed in this age group.

At the most basic conceptual level, | drought is a natural phenomenon in | which levels of rainfall or other types | of precipitation are lower than average for | an extended period of time, resulting in | inadequate water supply. To truly understand drought and its effect on people and | the environment, including human health | impacts, one must also consider differences | in geographic regions, local water demand, | and variables such as a community’s ability to adapt to water shortages and state | and local policies that regulate water supply (www.drought.unl.edu). For instance, | a significant amount of annual rainfall in | the southwestern U.S could be considered | a drought in the Northwest. The photo at | the top of page 11 illustrates recent conditions in the southeastern United States. As | a readily available supply of safe water is | a prerequisite for public health, droughts | have potential public health significance | and understanding the relationship between the two is an important first step in | examining potential associations.