Groundbreaking work by a team of South African medical researchers has exposed the damage the expected warmer weather in the near future will have on the health of workers.
The scientists say the health impacts of rising temperatures, especially in parts of the world that are already hot, could prove fatal in certain cases and could shrink economies significantly.
The team was led by Professor Angela Mathee, who?s the chief of the Environment and Health Unit at South Africa?s Medical Research Council and the director of the World Health Organization?s Collaborating Centre for Urban Health.
The study was part of an international project to investigate the implications of global warming on worker well-being and worker performance in various parts of the world.
South Africa was a particularly important study site as international climatologists say the country could be hard hit by climate change in the future. Some scientists have predicted that average temperatures in Africa?s strongest economy will climb by four degrees Celsius by 2100. Several uncharacteristic heat waves, poor rainfall patterns and droughts have struck it in recent years.
?People in many parts of my country are already working in conditions that are so hot that it is very uncomfortable for them and it?s putting their health at risk. If these conditions become more excessive it stands to reason that these health risks will increase substantially,? Mathee told VOA.
Heat?s physical toll
The medical researcher?s team studied workers in Johannesburg, South Africa?s major center of labor, and in the district of Upington, in Northern Cape province, where temperatures are often higher than 40 degrees Celsius (104 degrees Fahrenheit).
?We used workers like road construction workers, people who work in parks digging holes and on farms, people who were doing hard physical labor throughout the day,? Mathee explained.
She said almost all of the workers reported a wide range of health conditions, ?like thirst and excessive perspiration, itchy skin, being very tired or even exhausted, having dry or bleeding noses (and) blistered skin, severe leg pains, dizziness, feeling faint, insomnia and having backaches and headaches.?
In the South American leg of the study, researchers found that relatively young cane cutters are suffering from potentially fatal kidney conditions because they?re sweating out liters of water a day without replenishing enough of the lost liquids.
In South Africa, Mathee made similar ?disturbing? findings. She commented, ?Some of the workers were telling us that they have to carry as many as five to seven liters of water with them a day, and sometimes that is not enough.?
?Psychosocial? impacts and lower productivity
Mathee stated that as temperatures rose, the health problems suffered by the laborers became more intense, and they also endured less obvious, psychosocial effects on their well-being.
?The workers were telling us that on very hot days they become irritable, or they can?t sleep and they become angry with their family members for no other reason than the heat that they are suffering.?
The hotter the work conditions, Mathee explained, the higher the aggression levels of workers, with corresponding higher risk of friction and conflict in their workplaces and their homes.
She also said hotter weather could significantly decrease worker productivity in the near future. ?At a certain temperature (above 25 degrees C or 77 degrees F) you simply can?t be as productive,? said Mathee. ?Some of the workers, in our discussions with them, were saying things like, ?When it gets so hot we simply cannot keep up the pace of work, even in the morning.? So productivity is going to be a big concern (in the future), especially as far as African economies are concerned.?
Strategies to protect worker health
Mathee?s study concluded that many employers aren?t taking any steps to protect their laborers against hotter conditions.
?They aren?t supplying enough water, they aren?t providing shade; the workers schedules are not adapted (for them) to be able to cope with this kind of heat. They aren?t allowing them to start working early in the day, for example, and having longer siesta periods in the hottest part of the day,? she said, adding, ?Unfortunately right now a lot of workers are having to endure these higher temperatures with no relief and no effort on the part of employers at all to help them.?
Mathee did, however, emphasize that there are some good examples of preparation for higher workplace temperatures in South Africa. She pointed to some grape farms in Northern Cape province, where laborers begin work well before dawn, when it?s cooler. When temperatures start to soar, the workers continue their duties in air-conditioned pack houses.
Then, in South Africa?s KwaZulu-Natal province, some sugarcane farmers provide extremely strong lighting in their fields, which enables their workers to work at night and so to escape the heat of the day.
Mathee reflected, ?This study has been so useful. The main message for me is that we have to act immediately; there are a lot of basic public health measures that we could put in place right now to increase workers? comfort and to protect their health in the expected hotter weather of the future.?
She said these measures include ?setting guidelines for work undertaken above particular temperature thresholds; considering new work schedules and rotations ? for example earlier starting times or longer midday lunch break; providing safe water supplies to workers in sun-exposed settings; educating workers and supervisors about the signs and symptoms of heat stress and related intervention measures; providing shade for breaks and encouraging protective measures, such as providing sun hats and sunscreen lotions to workers.?