Background Occupational heat stress mediated acute kidney injury (AKI) has been linked to the development of chronic kidney disease of non-traditional causes (CKDnt) in agriculture workers. Rest-shade-hydration-hygiene (RSHH) programs are promising interventions for preventing CKDnt. An obstacle to the implementation of RSHH programs is the concern that the reduced work time associated with these programs may reduce productivity and earnings. This case study analyzes the economic impact of an RSHH program implemented at a sugar mill in Nicaragua.

Approach Data were obtained from the sugar mill over a six-year, five-harvest period (Harvest 1: 2017-18 through Harvest 5: 2021-2022). Data included health and productivity metrics, and RSHH program costs. During Harvest 1 existing heat mitigation strategies were in place but were not optimal. Thus, 2017 was considered the pre-RSHH (baseline) period. Over subsequent harvests progressively improved RSHH programs were implemented.

Analysis A cost-benefit analysis was conducted to estimate the return on investment of the RSHH program. The analysis considered both fixed and variable costs associated with the program, including electrolyte beverage production, costs for AKI treatment and worker training. Benefits were calculated based on productivity improvements, including reductions in absenteeism, and reductions in AKI cases.

Results As soon as 2020, the costs of implementing the RSHH program were offset by savings resulting from increased productivity (i.e., reduced absenteeism and increased worker production) and reduced cases of AKI. The RSHH program yielded a positive return on investment from 2020 and onward. The average return on investment over the five-year period was 0.02 (or a return of $1.02 for every $1.00 invested), which takes into consideration the first two years of the intervention in which there was a negative return on investment. In 2022, every $1.00 invested in the RSHH program saw a return of $1.60.

Discussion This case study provides evidence that implementing an RSHH program can provide both economic and health benefits, particularly in locations where climate change is increasing the already present risk and burden of occupational heat stress.

Teaser message A rest-shade-hydration-hygiene intervention program at a sugar mill in Nicaragua produced a positive return on investment after five years by improving both health and productivity outcomes.

Key findings and implications

A positive average return on investment of $1.60 USD for every $1.00 invested was identified after a five-year period following implementation of a rest-shade-hydration-hygiene (RSHH) program at a sugar mill in Nicaragua.

Three years after implementation, the costs of implementing the RSHH program were offset by savings resulting from increased productivity (i.e., reduced absenteeism and increased worker production) and reduced cases of acute kidney injury.

This case study provides evidence of the health and economic benefits of promoting an easily applicable workplace intervention that addresses current risks as well as the rising threat of climate change induced occupational heat stress.

The authors have declared no competing interest.

The preparation of this case study manuscript was supported by the following awards: National Institutes of Health - Fogarty International Center, the National Institute of Occupational Safety and Health (R01OH011528), The Protection Resilience Efficiency and Prevention (PREP) for workers in industrial agriculture in a changing climate project was funded by Forte (FORTE 2019-01548; Sweden); NOAA (USA), NSF (USA) and UKRI (NERC; NE/T013702/1; UK). This manuscript is a part of a supplement titled, Lessons from the field: Case studies to advance research on climate adaptation strategies and their impact on public health. This writing project was supported by the National Institutes of Health (NIH) Climate Change and Health Initiative (https://climateandhealth.nih.gov) and coordinated by the Center for Global Health Studies at the Fogarty International Center of NIH. The activity was led by a steering committee of global experts on health and climate change. More information is available at https://go.nih.gov/ClimateAdaptationStudies.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Comite de Etica para Investigaciones Biomedicas (CEIB), Facultad de Ciencias Medicas, Universidad Nacional Autonoma de Nicaragua (UNAN-Leon), FWA000045231/IRB00003342

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Data produced in the present study are available upon reasonable request to the authors