Fluctuation of Water Intake and of Hydration Indices during the Day in a Sample of Healthy Greek Adults

Risk factors associated with indicators of dehydration among migrant farmworkers

OBJECTIVE

Farmworkers are at increased risk of adverse health outcomes related to occupational heat exposure and inadequate access to water, shade, or rest breaks. Presently, there is a dearth of studies examining the prevalence of dehydration and related factors in U.S. farmworkers. Our objectives were to characterize hydration status during typical workdays and to identify risk factors associated with increased dehydration in migrant farmworkers employed in Florida.

METHODS

Urine samples were collected and analyzed for urine specific gravity (USG) 2-3 times per person per day over five days in May 2021 and 2022. Data collection included demographic characteristics, wet-bulb-globe-temperature (WBGT), and information on working conditions (task type, duration, and crop units harvested), fluid intake, clothing worn, and heat safety behaviors. Multivariable mixed regression models were used to evaluate risk factors associated with change in USG levels (continuous) during a work shift.

RESULTS

A total of 111 farmworkers participated in this study providing 1020 cumulative USG measurements, of which 96.8% of end-of-shift USG samples were above 1.020 indicating potential dehydration. In multivariable models, dehydration assessed using change in USG levels significantly declined with age (β = -0.078; 95%CI: 0.150, -0.006) but showed significant increase with body mass index (β = 0.016; 95%CI: 0.003, 0.028), WGBT (β = 0.054; 95%CI:0.044, 0.064), mean shift duration, and state of primary residence. We did not find significant associations of dehydration with type of clothing worn, intake of employer-provided water, or crop units harvested during a shift in this sample of farmworkers.

CONCLUSION

Our findings underscore the need for additional research to evaluate adverse outcomes related to dehydration and to better understand recovery patterns from chronic dehydration across workweeks and harvest seasons in migrant farmworkers.

Biomarker Reproducibility Challenge: A Review of Non-Nucleotide Biomarker Discovery Protocols from Body Fluids in Breast Cancer Diagnosis

Breast cancer has now become the most commonly diagnosed cancer, accounting for one in eight cancer diagnoses worldwide. Non-invasive diagnostic biomarkers and associated tests are superlative candidates to complement or improve current approaches for screening, early diagnosis, or prognosis of breast cancer. Biomarkers detected from body fluids such as blood (serum/plasma), urine, saliva, nipple aspiration fluid, and tears can detect breast cancer at its early stages in a minimally invasive way. The advancements in high-throughput molecular profiling (omics) technologies have opened an unprecedented opportunity for unbiased biomarker detection. However, the irreproducibility of biomarkers and discrepancies of reported markers have remained a major roadblock to clinical implementation, demanding the investigation of contributing factors and the development of standardised biomarker discovery pipelines. A typical biomarker discovery workflow includes pre-analytical, analytical, and post-analytical phases, from sample collection to model development. Variations introduced during these steps impact the data quality and the reproducibility of the findings. Here, we present a comprehensive review of methodological variations in biomarker discovery studies in breast cancer, with a focus on non-nucleotide biomarkers (i.e., proteins, lipids, and metabolites), highlighting the pre-analytical to post-analytical variables, which may affect the accurate identification of biomarkers from body fluids.

Mass spectrometry-based tear proteomics for noninvasive biomarker discovery

The lacrimal film has attracted increasing interest in the last decades as a potential source of biomarkers of physiopathological states, due to its accessibility, moderate complexity, and responsiveness to ocular and systemic diseases. High-performance liquid chromatography-mass spectrometry (LC-MS) has led to effective approaches to tear proteomics, despite the intrinsic limitations in sample amounts. This review focuses on the recent progress in strategy and technology, with an emphasis on the potential for personalized medicine. After an introduction on lacrimal-film composition, examples of applications to biomarker discovery are discussed, comparing approaches based on pooled-sample and single-tear analysis. Then, the most critical steps of the experimental pipeline, that is, tear collection, sample fractionation, and LC-MS implementation, are discussed with reference to proteome-coverage optimization. Advantages and challenges of the alternative procedures are highlighted. Despite the still limited number of studies, tear quantitative proteomics, including single-tear investigation, could offer unique contributions to the identification of low-invasiveness, sustained-accessibility biomarkers, and to the development of personalized approaches to therapy and diagnosis.

Estimates of fluid intake, urine output and hydration-levels in women from Somaliland: a cross-sectional study

The study objective was to measure fluid intake and associations with background characteristics and hydration biomarkers in healthy, free-living, non-pregnant women aged 15–69 years from Hargeisa city. We also wanted to estimate the proportion of euhydrated participants and corresponding biomarker cut-off values. Data from 136 women, collected through diaries and questionnaires, 24h urine samples and anthropometric measurements, were obtained with a cross-sectional, purposeful sampling from fifty-two school and health clusters, representing approximately 2250 women. The mean (95 % CI) 24 h total fluid intake (TFI) for all women was 2⋅04 (1⋅88, 2⋅20) litres. In multivariate regression with weight, age, parity and a chronic health problem, only weight remained a predictor (P 0.034, B 0.0156 (l/kg)). Pure water, Somali tea and juice from powder and syrup represented 49⋅3, 24⋅6 and 11⋅7 % of TFI throughout the year, respectively. Mean (95 % CI) 24 h urine volume (Uvol) was 1⋅28 (1⋅17, 1⋅39) litres. TFI correlated strongly with 24 h urine units (r 0.67) and Uvol (r 0.59). Approximately 40 % of the women showed inadequate hydration, using a threshold of urine specific gravity (Usg) of 1⋅013 and urine colour (Ucol) of 4. Five percent had Usg > 1⋅020 and concomitant Ucol > 6, indicating dehydration. TFI lower cut-offs for euhydrated, non-breast-feeding women were 1⋅77 litres and for breast-feeding, 2⋅13 litres. Euhydration cut-off for Uvol was 0⋅95 litre, equalling 9⋅2 urine units. With the knowledge of adverse health effects of habitual hypohydration, Somaliland women should be encouraged to a higher fluid intake.

Risk Assessment of Glyphosate Exposures from Pilot Study with Simulated Heavy Residential Consumer Application of Roundup® using a Margin of Safety (MOS) Approach

Due to the widespread application of glyphosate, a nonselective herbicide, to a variety of resistant food crops, the general population is exposed to glyphosate through dietary intake. Despite this, dietary exposures to glyphosate are considered low in comparison to application-related exposures. Although previous studies have evaluated exposure to horticultural and agricultural workers, to date only one study, which we recently conducted, has characterized exposure to glyphosate in consumers following heavy residential application of a glyphosate-containing herbicide in a residential yard and garden setting. In this previous study, we demonstrated that urinary glyphosate concentrations in these applicators were similar to or in some circumstances greater than those in occupational applicators, likely due to the nature of the simulation study, which ensured a heavy application protocol. However, it is unknown whether these urinary glyphosate concentrations in consumer applicators correspond to internal doses that may be of concern. Therefore, the purpose of this study is to provide a comprehensive risk assessment of glyphosate exposure in consumer applicators using a margin of safety approach. Here, we incorporated data collected from multiple spot urine samples across time from our previous study that assessed consumer exposure to glyphosate from Roundup® application. Estimated internal doses, even with the use of conservative assumptions across unique approaches, were below internal doses estimated from established health-based guidance values. Overall, this study demonstrates that glyphosate exposure from even heavy consumer application of a commercially available glyphosate-containing herbicide does not appear to be a health concern.

The Timing of Water and Beverage Consumption During the Day Among Children and Adults in the United States: Analyses of NHANES 2011-2016 Data

Dietary Guidelines for Americans 2015–20 recommend replacing sugar sweetened beverages (SSBs) with plain water in order to promote adequate hydration while reducing added sugar intake. This study explored how water intakes from water, beverages, and foods are distributed across the day. The dietary intake data for 7453 children (4–18 y) and 15,263 adults (>19 y) came from the National Health and Nutrition Examination Survey (NHANES 2011–2016). Water was categorized as tap or bottled. Beverages were assigned to 15 categories. Water intakes (in mL/d) from water, beverages, and food moisture showed significant differences by age group, meal occasion, and time of day. Plain water was consumed in the morning, mostly in the course of a morning snack and between 06:00 and 12:00. Milk and juices were consumed at breakfast whereas SSBs were mostly consumed at lunch, dinner, and in the afternoon. Children consumed milk and juices, mostly in the morning. Adults consumed coffee and tea in the morning, SSBs in the afternoon, and alcohol in the evening. Relatively little drinking water was consumed with lunch or after 21:00. Dietary strategies to replace caloric beverages with plain water need to build on existing drinking habits by age group and meal type.