February 1st, 2017 (Updated February 10th, 2017 to include language that makes it emphatic that we believe A. Water, Rest and Shade (WRS) is a basic human right B. Regardless of CKDnT WRS programs should be scaled up, though they should be rigorously monitored for effectiveness)

To: All Interested Sugarcane Stakeholders
From: The Worker Health and Efficiency (WE) Working Group
Re: Scope, Impact and Results of the WE Program’s Water Rest and Shade Intervention Study

The Worker Health and Efficiency (WE) Working Group wishes to summarize the scope, impact and results of our Water.Rest.Shade (WRS) intervention study as well as to make clear the limits we place on the interpretation of the study thus far, specifically concerning the prevention of Chronic Kidney Disease of undetermined cause (CKDnT).

What is an intervention Study?

It is well documented that working long hours in direct sunlight or hot environments has many acute adverse health effects, most dire being heat stroke and death. Also well known is that these health effects can be ameliorated if adequate water and time for rest away from direct sun (Water.Rest.Shade – WRS) is provided. We are aware that a number of sugarcane companies are currently implementing some version of such a WRS program and applaud their initiative.

The Worker Health and Efficiency research program is a formal intervention protocol designed to determine if an intervention providing a health program (clean water throughout the day, scheduled rest breaks of appropriate frequency, and accessible rest under the shade) coupled with an efficiency program (properly designed machetes and a better work pattern of row-cutting) can be shown to reduce or eliminate the development of kidney damage that can ultimately result in chronic kidney disease.

Our Findings

The evidence gathered so far in the WE Program is that a water rest & shade intervention is feasible in sugarcane fields, and appears to markedly reduce the impact of the heat stress conditions for the workforce. With proper attention to work practices, production can be maintained with less impact on worker health.

However, we cannot conclude that the intervention prevents kidney damage – more research in a longer timeframe is needed before determining that such a program prevents CKDnT.

Individuals or organizations claiming the WE Program has sufficiently shown that the intervention can prevent chronic kidney damage in sugarcane workers have over-interpreted the implications of our research. We cannot endorse claims regarding the impact of the WE intervention design with respect to CKDnT prevention.

Our Concern

Prematurely claiming that CKDnT onset and progression can be stopped via the WE Program, or similar programs, could damage the funding and policy environment on which serious research and interventions depend. If it is erroneously believed CKDnT has been adequately addressed, support will be more difficult to acquire. This would negatively impact workers and communities depending on rigorous research.

Our Hope

We are in talks with sugar producers to design, and validate, a W.R.S. program using the collective experience and data each party brings. Our hope is that W.R.S. programs continue to expand regardless of CKDnT mitigation, as the provision of water and shaded rest is a fundamental necessity for worker health and a human right.

We of course would like to state the WE Program is already fully successful at preventing CKDnT. However, our job as researchers is to critically evaluate if such interventions are enough to stop, or slow down, the onset of CKDnT.

Our hope is that all parties sharing the objective of understanding how we can design and measure the most effective program possible may work together with the clarity, patience, responsibility and rigor necessary in such a serious undertaking.


Dr. David Wegman
Dr. Ineke Wesseling
Dr. Theo Bodin
Dr. Kristina Jakobsson
Dr. Christer Hogstedt
Dr. Ulf Ekström
Dr. Rebekah Lucas
Ilana Weiss
Jason Glaser

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