Atrazine in public water supplies and risk of ovarian cancer among postmenopausal women in the Iowa Women's Health Study

Background

Few studies have evaluated environmental chemical exposures in relation to ovarian cancer. We previously found an increased risk of ovarian cancer among postmenopausal women in Iowa associated with higher nitrate levels in public water supplies (PWS). However, elevated nitrate levels may reflect the presence of other agricultural chemicals, such as atrazine, one of the most commonly detected pesticides in Iowa PWS.

Methods

We evaluated the association between atrazine in drinking water and incident ovarian cancer (N=145, 1986–2010) among 13 041 postmenopausal women in the Iowa Women's Health Study who used their PWS for ≥11 years as reported in 1989. Average levels of atrazine (1986–1987), nitrate-nitrogen (NO₃-N, 1955–1988) and estimated levels of total trihalomethanes (TTHM, 1955–1988) from PWS monitoring data were linked to the participants' cities of residence. We computed HRs and 95% CIs by categories of the average atrazine level (not detected, ≤ or >0.37 parts per billion=median) using Cox proportional hazards regression adjusting for ovarian cancer risk factors.

Results

Atrazine was detected in water samples from 69 cities where 4155 women (32%) lived and levels were moderately correlated with NO₃-N (=0.35) and TTHM (=0.24). Atrazine levels were not associated with ovarian cancer risk with or without adjusting for NO₃-N and TTHM levels (p-trend=0.50 and 0.81, respectively). Further, there was no evidence for effect modification of the atrazine association by NO₃-N or TTHM levels.

Conclusions

In our study with low atrazine detection rates, we found no association between atrazine in PWS and postmenopausal ovarian cancer risk.

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'Should we consider renaming 'Mesoamerican Nephropathy as Nephropathy of Unknown Cause in Agricultural Labourers (NUCAL)?

Mesoamerican nephropathy (MAN) refers to a kidney disease that primarily afflicts male labourers (usually in the agricultural sector) and has been mainly identified in regions of Central America.1 While the global prevalence and incidence is not known, in the regions where the condition has been recognised, the prevalence has been noted to be between 10% and 15%. Nearly 20 000 deaths have been attributed to this condition from El Salvador alone.2 The aetiology is unclear. It is thought to be contributed to by dehydration, malnutrition, fructose ingestion, electrolyte imbalance, pesticides, environmental toxins and heat injury. The role of genetics or other patient factors is unclear. Clusters of kidney disease with similar presentation have been identified in agricultural labourers in India, Egypt and Sri Lanka. The histopathology of this condition is characterised by interstitial fibrosis and tubular atrophy with glomerulosclerosis similar to that from Central America.3...

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Relationship between cumulative exposure to 1,2-dichloropropane and incidence risk of cholangiocarcinoma among offset printing workers

Objectives

This study aimed to evaluate the relationship between cumulative exposure to 1,2-dichloropropane (1,2-DCP) and incidence risk of cholangiocarcinoma among workers in the offset proof-printing section of a small printing company in Osaka, Japan.

Methods

We identified 95 workers of a printing company (78 men and 17 women) who had been exposed to 1,2-DCP between 1987 and 2006, and calculated the standardised incidence ratio (SIR) of cholangiocarcinoma from 1987 to 2012. We estimated cumulative exposure to 1,2-DCP and calculated SIRs in four exposure categories. We also calculated incidence rate ratios (RRs) adjusted by sex, age, calendar year and dichloromethane (DCM) exposure for three exposure categories using Poisson regression analysis.

Results

Cumulative exposures to 1,2-DCP ranged from 32 to 3433 ppm-years (mean, 851 ppm-years) and the SIR was 1171 (95% CI 682 to 1875). In the analysis of the four exposure categories, SIRs increased significantly in the three highest exposure categories, but not in the lowest category. Adjusted RRs in the middle and high exposure categories were 14.9 (95% CI 4.1 to 54.3) and 17.1 (95% CI 3.8 to 76.2), respectively, in the analysis without lag time, and were 11.4 (95% CI 3.3 to 39.6) and 32.4 (95% CI 6.4 to 163.9), respectively, in the analysis with a 5-year lag. The trend analysis revealed a significant increase in RR in association with increasing cumulative exposure to 1,2-DCP. DCM exposure was not significantly associated with the development of cholangiocarcinoma.

Conclusions

The present study demonstrated an exposure–response relationship between exposure to 1,2-DCP and the development of cholangiocarcinoma.

http://ift.tt/2964w8V

IJERPH, Vol. 13, Pages 671: Suicide: Incidence or Prevalence? Comments on Hernández-Alvarado et al. Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012. Int. J. Environ. Res. Public Health 2016, 13, 552

I recently reviewed the paper published in this journal by Hernández-Alvarado et al., titled “Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012” [1], and I noticed that the epidemiological concept “prevalence” is not correctly used.[...]

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IJERPH, Vol. 13, Pages 672: Response to the Fernández-Niño Comments on Hernández-Alvarado et al. Increase in Suicide Rates by Hanging in the Population of Tabasco, México between 2003 and 2012. Int. J. Environ. Res. Public Health 2016, 13, 552

We thank the comments of Fernández-Niño [1] addressing our article [2] “Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012”, which pointed out that the use of the epidemiological concept “prevalence” is not correctly applied in the present manuscript.

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IJERPH, Vol. 13, Pages 666: Community-Based Management of Child Malnutrition in Zambia: HIV/AIDS Infection and Other Risk Factors on Child Survival

(1) Background: Supplementary feeding programs (SFPs) are effective in the community-based treatment of moderate acute malnutrition (MAM) and prevention of severe acute malnutrition (SAM); (2) Methods: A retrospective study was conducted on a sample of 1266 Zambian malnourished children assisted from 2012 to 2014 in the Rainbow Project SFPs. Nutritional status was evaluated according to WHO/Unicef methodology. We performed univariate and multivariate Cox proportional risk regression to identify the main predictors of mortality. In addition, a time-to event analysis was performed to identify predictors of failure and time to cure events; (3) Results: The analysis included 858 malnourished children (19 months ± 9.4; 49.9% males). Program outcomes met international standards with a better performance for MAM compared to SAM. Cox regression identified SAM (3.8; 2.1–6.8), HIV infection (3.1; 1.7–5.5), and WAZ <−3 (3.1; 1.6–5.7) as predictors of death. Time to event showed 80% of children recovered by SAM/MAM at 24 weeks. (4) Conclusions: Preventing deterioration of malnutrition, coupled to early detection of HIV/AIDS with adequate antiretroviral treatment, and extending the duration of feeding supplementation, could be crucial elements for ensuring full recovery and improve child survival in malnourished Zambian children.

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IJERPH, Vol. 13, Pages 670: Approaches to Children’s Exposure Assessment: Case Study with Diethylhexylphthalate (DEHP)

Children’s exposure assessment is a key input into epidemiology studies, risk assessment and source apportionment. The goals of this article are to describe a methodology for children’s exposure assessment that can be used for these purposes and to apply the methodology to source apportionment for the case study chemical, diethylhexylphthalate (DEHP). A key feature is the comparison of total (aggregate) exposure calculated via a pathways approach to that derived from a biomonitoring approach. The 4-step methodology and its results for DEHP are: (1) Prioritization of life stages and exposure pathways, with pregnancy, breast-fed infants, and toddlers the focus of the case study and pathways selected that are relevant to these groups; (2) Estimation of pathway-specific exposures by life stage wherein diet was found to be the largest contributor for pregnant women, breast milk and mouthing behavior for the nursing infant and diet, house dust, and mouthing for toddlers; (3) Comparison of aggregate exposure by pathways vs biomonitoring-based approaches wherein good concordance was found for toddlers and pregnant women providing confidence in the exposure assessment; (4) Source apportionment in which DEHP presence in foods, children’s products, consumer products and the built environment are discussed with respect to early life mouthing, house dust and dietary exposure. A potential fifth step of the method involves the calculation of exposure doses for risk assessment which is described but outside the scope for the current case study. In summary, the methodology has been used to synthesize the available information to identify key sources of early life exposure to DEHP.

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