UI study looks at ag machinery vibration, back pain among farmers

combine harvesting cornDuring harvest season, it’s common for farmers to work 10 to 14 hours a day. Long hours sitting on agricultural equipment can take a physical toll on the body and lead to back pain.

A new study conducted by researchers at the University of Iowa College of Public Health examined whole-body vibration exposures during the operation of several types of agricultural machinery. Whole-body vibration is defined as mechanical vibrations that are transmitted to the human body through a contact surface, such as a seat.

“Exposure to whole-body vibration is a key occupational risk factor for back pain, which is common among agricultural workers,” says the study’s lead investigator, Nathan Fethke, CPH associate professor of occupational and environmental health. “Spending many hours operating machinery can increase the frequency of back pain episodes and, if the pain is severe or becomes chronic, medical costs can be quite high.”

A previous study found that costs associated with lower back pain in the United States exceeded $100 billion per year, two thirds of which are a result of lost wages and productivity. Reducing exposures to whole-body vibration can help improve health and may reduce long-term health care costs.

Fethke’s team measured whole-body vibration by attaching sensors to the seats of more than 100 machines, including tractors, combines, forklifts, skid loaders, and all-terrain vehicles (ATVs), as more than 50 Midwestern farmers went about their daily routines.  An additional sensor attached to the floor of each machine allowed Fethke’s team to examine how effectively the seats reduced the vibration levels. A paper describing results of the study appears in Annals of Work Exposure and Health.

A portrait of Nate Fethke, professor of Occupational and Environmental Health at the University of Iowa College of Public Health.
Nathan Fethke

The average vibration levels were compared to the European Union’s (EU) whole-body vibration exposure limits, which are similar to recommendations made by the American Conference of Governmental Industrial Hygienists. The U.S. Occupational Safety and Health Administration does not enforce a whole-body vibration standard. The whole-body vibration levels of nearly 30% of the machines were high enough to reach EU’s “action level” within only two hours of operation. The action level is defined as the level above which the risk of health effects increases.

Combines exhibited the lowest levels of whole-body vibration exposures, which, according to Fethke, is “likely due to a combination of the mass of combines compared to other machine types and the common presence of relatively sophisticated seat suspension systems.” The combine seats reduced by half the amount of vibration measured at the floor.

Tractors and heavy utility vehicles did not fare as well, with average vibration levels about double what was measured on combines.

“Special seat-based suspension systems, particularly on tractors, did not dramatically reduce whole-body vibration like we thought they would– it is possible that these suspension systems were not properly adjusted to the weight of the operator, or had degraded over time from mechanical wear and tear,” Fethke says.

Farmers should check seat suspension systems to make sure they are greased and working properly. They should also make sure the seat suspension is properly adjusted for the operator’s body weight.  This is especially important if several workers or family members will be operating the equipment.  If the seat tends to frequently “bottom out,” even after proper adjustment for body weight and routine maintenance, it is time to consider a replacement.

Finally, the potential effects of whole-body vibration on back pain and discomfort also depend on the operator’s posture in the seat.

“As any experienced agricultural equipment operator knows, it is often necessary to lean far forward or look to the side or behind the equipment for visibility purposes. However, these twisting postures change how the body responds to vibration and can increase the risk of back problems down the road,” says Fethke.

The study is one of few to look at whole-body vibration during the operation of agricultural machinery.  The article, Whole-Body Vibration and Trunk Posture during Operation of Agricultural Machinery, is available online at https://academic.oup.com/annweh/advance-article/doi/10.1093/annweh/wxy076/5104230 .

For posters and handouts in English and Spanish with recommendations on reducing whole-body vibration, visit http://bit.ly/WBVrecommendations.

‘Food Chains’ documentary will be shown Oct. 12

poster for Food Chains filmIn recognition of National Hispanic Heritage Month, the College of Public Health will host two screenings of the documentary film Food ChainsThe screenings are sponsored by the CPH Diversity and Inclusion Committee and the UI Latino Council.

Monday, October 2
CPH Spotlight Series: Partial Screening and Panel Discussion
12:30 – 1:30 p.m.

A segment of the film will be shown followed by a panel discussion.
Lunch will be provided. Please RSVP by emailing cph-spotlight@uiowa.edu

Corrected date:  Thursday, October 12
Full Screening
5:30 p.m.

A reception will follow in the atrium. Admission is free and open to the public.

About the Film

There is more interest in food these days than ever, yet there is very little interest in the hands that pick it. Farmworkers, the foundation of our fresh food industry, are routinely abused and robbed of wages. In extreme cases they can be beaten, sexually harassed or even enslaved – all within the borders of the United States.

Food Chains reveals the human cost in our food supply and the complicity of large buyers of produce like fast food and supermarkets. Fast food is big, but supermarkets are bigger – earning $4 trillion globally. They have tremendous power over the agricultural system. Over the past 3 decades they have drained revenue from their supply chain, leaving farmworkers in poverty and forced to work under subhuman conditions. Yet many take no responsibility for this.

In this exposé, an intrepid group of Florida farmworkers battle to defeat the $4 trillion global supermarket industry through their ingenious Fair Food program, which partners with growers and retailers to improve working conditions for farm laborers in the United States.

Individuals with disabilities are encouraged to attend all University of Iowa-sponsored events. If you are a person with a disability who requires a reasonable accommodation in order to participate in this program, please contact the College of Public Health in advance at (319) 384-1500. This film has captioning available.

Research: Farmers still take own lives at a high rate

The number of suicides among farmers and farmworkers in the United States has remained stubbornly high since the end of the 1980s farm crisis, much higher than workers in many other industries, according to a new study from the University of Iowa.

The study examined suicides and homicides among farmers and agricultural workers across the country from 1992 to 2010 and found 230 farmers committed suicide during that time, an annual suicide rate that ranged from 0.36 per 100,000 farmers to 0.95 per 100,000. The rate is well above that of workers in all other occupations, which never exceeded 0.19 per 100,000 during the same time period.

The 1992 to 2010 rate is not as high as the 1980s, when more than 1,000 farmers took their own lives because they were losing their farms to foreclosure, but study co-author Corinne Peek-Asa, professor of occupational and environmental health in the UI College of Public Health, says the new numbers still are excessive.

“Occupational factors such as poor access to quality health care, isolation, and financial stress interact with life factors to continue to place farmers at a disproportionately high risk for suicide,” she says.

The survey found farmers in the West were more likely to commit suicide, at 43 percent of total farmer suicides, followed by the Midwest (37 percent), South (13 percent), and Northeast (6 percent).

As in the 1980s, financial issues continue to cause some suicides, especially during economic crises or periods of extreme weather, Peek-Asa says. But farmers face an array of other stresses that put them at high risk for suicide: physical isolation from a social network, leading to loneliness; physical pain from the arduous work of farming; and lack of available health care resources in rural areas, especially mental health care. She says other research also suggests that exposure to chemical insecticides causes depression in some people.

In addition, Peek-Asa says, farm culture dictates that farmers who may have physical or psychological needs should just suck it up and go about their work.

Finally, farmers have access to lethal means because many of them own weapons. The rifle they use to chase off coyotes can easily be turned on themselves.

Peek-Asa says farmers are different from workers in most other fields in that their work is a significant part of their identity, not just a job. When the farm faces difficulties, many see it as a sign of personal failure.

“They struggle with their ability to carve out the role they see for themselves as farmers. They can’t take care of their family; they feel like they have fewer and fewer options and can’t dig themselves out,” Peek-Asa says. “Eventually, suicide becomes an option.”

Peek-Asa says policy solutions would include include improving rural economies, increasing social networks in rural areas, and improving access to health care and mental health services in rural areas.

Beyond that, she says improving the quality of life in rural communities also is important, pointing to UI programs that contribute to that, such as the mobile museum or Hancher’s summer art outreach program that brings arts and cultural opportunities to towns and cities across Iowa.

The study, “Trends and Characteristics of Occupational Suicide in Farmers and Agriculture Workers,” was published in the Journal of Rural Health. It was co-authored by Kelley Donham, UI professor emeritus in the College of Public Health; Marizen Ramirez of the University of Minnesota and visiting associate professor in the UI College of Public Health; and Wendy Ringgenberg of Des Moines University.

(This story originally appeared in Iowa Now)

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