Assessment of construction workers’ hydration status using urine specific gravity

Abstract

Objectives: The study objective was to assess hydration status by measuring USG among construction workers in Iran. Materials and Methods:The study design was comparative and experimental. Sixty participants were randomly selected from the construction workers from a construction campus with a similar type of work, climate and diet and formed 2 groups (individuals exposed to the sun and non-exposed individuals). TWL and USG were measured in both groups on 2 consequent days, at the beginning, mid and end of the work shift. Results: USG test showed that mean USG was 1.0213±0.0054 in the control group and in the exposed group, where it was significantly higher, it amounted to 1.026±0.005. In the exposed group, 38% of workers had a USG level between 1.026-1.030, representing a higher risk of heat illness and impaired performance and 12.72% had a USG level above 1.030 representing a clinically dehydrated status, while this proportion in the control group was 15.2% and 0.58%, respectively. The mean TWL index measure was 215.8±5.2 W/m 2 for the control group and 144±9.8 W/m 2 for the exposed group, where, again, it was significantly higher. The Pearson correlation measure showed a significant correlation between USG and TWL. Conclusions: Strong correlation between TWL, as an indicator of thermal stress and USG shows that USG can be considered as a predictor of thermal stress. The difference between USG among the exposed and non-exposed workers and the increase in USG during midday work show the sensitivity of this measure in different thermal and climatic conditions, whereas, the high level of dehydration among workers despite acceptable TWL level, shows that heat stress management without considering the real hydration status of workers, is insufficient.

Angiotensin-Converting Enzyme Ins/Del Polymorphism and Body Composition: The Intermediary Role of Hydration Status

“…During the last decades, the new insights in the active role of adipose tissue as a metabolic active organ focused the attention on the fat mass component in the evaluation of body health. However, even if this is surely a remarkable aspect, also the FFM content of each individual as an index of health is of growing importance [19,20,28,29], in particular in terms of phase angle (PhA) and BCMI. So, PhA and BCMI have been proposed as other indices capable to describe body composition in terms of fat mass and lean mass in addition to the traditional BMI, to better define metabolic health [18,19,20].…”

“…Urine osmolality has been unambiguously associated with insufficient water intake, and it is less invasive, expensive and more sensitive to mild cell dehydration than other indicators [2]. The population has been divided in 2 classes according to hydration status: norm-hydrated subjects with USG <1,020 and dehydrated subjects with USG >1,021 [20]. …”

“…BCM was normalized for height by calculating the BCM index (BCMI) [18]. The BIA PhA, calculated as the arctangent of the directly measured reactance-to-resistance ratio [19], correlates with various indices of functional and nutritional status and it is the most clinically established impedance parameter [20]. In particular, PhA has been suggested as a muscularity index and an indicator of cellular health with higher values representing higher cellularity, cell membrane integrity, and better cell function [19].…”

Provision of an Empirical Model to Estimate the Adaptive Capacity of Workers at Risk of Heat Stress

“…Another study (2007) was conducted on workers of surface mines located in Pilbara in Western Australia; and the results obtained from urine samples revealed that 70% of 710 workers were subjected to water scarcity and that 16% of workers needed clinical services (34). Similar conditions were reported for construction workers in Iran (35) and United Arab Emirates (34). Education is important in helping workers maintain their hydration state.…”

Heat stress intervention research in construction: gaps and recommendations

“…Strategies for developing these interventions have been focused on the process of quantifying heat stress (causes) and strain (consequences). For instance, Bates and Schneider25 ) , Bates et al 27 ) , Miller and Bates28 ) , and Montazer et al 29 ) investigated the hydration status of construction workers and advised that interventions are required to maintain adequate levels of hydration of workers under extreme heat stress conditions. Chan et al 30, 31 ) , Yi and Chan8, 26, 32 ) , Rowlinson and Jia9 ) , and Pérez-Alonso et al 1 ) proposed work and/or recovery thresholds after examining body heat strain limits arising from multiple heat stressors (e.g., meteorology, work and individual characteristics) in the Hong Kong construction industry.…”