Impact of heat stress on thermal balance, hydration and cortical response among outdoor workers in hot environment – an exploratory report from North East India

Krishnan Srinivasan; Chaki G. Boulton; Manasi Bhattacharjee; Abhishek Sinha; Sundareswaran Loganathan; Ashikh Seethy; Saklain M. Alam; Benzamin Hanse

doi:10.1515/jbcpp-2024-0003

Article

Impact of heat stress on thermal balance, hydration and cortical response among outdoor workers in hot environment – an exploratory report from North East India

Krishnan Srinivasan , Chaki G. Boulton , Manasi Bhattacharjee , Abhishek Sinha , Sundareswaran Loganathan , Ashikh Seethy , Saklain M. Alam and Benzamin Hanse

Published/Copyright: March 13, 2024

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From the journal Journal of Basic and Clinical Physiology and Pharmacology Volume 35 Issue 1-2

Abstract

Objective

The objective of our study was to assess the impact of heat stress on hydration and cognition among outdoor workers in hot environment.

Methods

Area heat stress assessments were measured using Quest Temp WBGT monitor. Sweat rate for dehydration and reaction time for acute cognitive processing were recorded using standard procedures.

Results

Heat stress measurements ranged from 23.8 °C – 42 °C. More than 50 % of the workers had high sweat rate (>1.2 L/h) when exposed to high environmental temperatures. Positive correlation was obtained between WBGT, sweat rate and reaction time which indicates that hyperthermia has an impact on neural network processing. Heart rate and reaction time also increased with rise in WBGT and heavy physical activity.

Conclusions

There was impairment of cognitive functions (reaction time) under heat stress conditions. Hence, reaction time can be used to assess the short-term impact of heat stress on neural modulation and will help to plan effective intervention strategies to reduce morbidity and mortality among workers.

Keywords: WBGT (Wet Bulb Globe Thermometer); heat strain; core body temperature; reaction time; sweat rate

Corresponding author: Dr. Krishnan Srinivasan, Assistant Professor, Department of Physiology, AIIMS, Guwahati 781101, Assam, India, E-mail: drkrish10@gmail.com

Funding source: Department of Health Research, India

Award Identifier / Grant number: GIA 1961-2022

Acknowledgments

We extend our heartfelt thanks to the funding agency, ICMR-DHR, for their financial support.

Research ethics: Ethical approval obtained from the host institute.
Informed consent: Informed consent was obtained from all individuals included in this study.
Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission. Dr. Krishnan S: conceptualization of the idea, study design, methodology, project implementation, coordination of data collection, data management, data analysis; Chaki G Bolton: study design, methodology, project implementation, data collection; Prof. Manasi Bhattacharjee: conceptualization of the idea, study design, methodology, coordination of data collection; Dr. Naveen P: conceptualization of the idea, study design; Dr. Abhishek Sinha: conceptualization of the idea, study design, data collection, data analysis; Dr. Sundareswaran L: conceptualization of the idea, study design, data collection, data analysis and manuscript preparation; Dr. Ashikh Seethy: study design, data collection, data analysis and manuscript preparation; Saklain M Alam: data collection, data analysis and manuscript preparation; Benzamin Hanse: data collection, data analysis and manuscript preparation.
Competing interests: Authors state no conflict of interest.
Research funding: ICMR-DHR GIA 1961–2022, Govt of India.
Data availability: The raw data can be obtained on request from the corresponding author.

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Received: 2024-01-08

Accepted: 2024-02-21

Published Online: 2024-03-13

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Articles in the same Issue

https://doi.org/10.1515/jbcpp-2024-0003

Keywords for this article

WBGT (Wet Bulb Globe Thermometer); heat strain; core body temperature; reaction time; sweat rate