Trauma from Overexertion or Repetitive Motion

Ergonomic hazards refer to physical demands placed on the body that can lead to disorders and loss of function. Agricultural work in particular has been linked to muscu­loskeletal trauma due to the stresses on the body of constant bending, lifting, twisting, and other awkward or punishing work. In the European Union for example, close to 60% of workers in agriculture and fishing are exposed to painful positions at work half the time or more and 50% carry heavy loads at work half the time or more.

Numerous farming tasks such as propagation and harvesting require workers to stand, bend, or stoop in demanding positions for long periods of time. Sprains, strains, and overexertion are all common injuries, espe­cially for workers engaged in manual cultivation. Nursery workers engage in repetitive gripping and cutting. They work virtually full-time year round without rotation to other jobs. In the short term, horticultural workers often report pain and numbness in the hand, wrist, and arm.

After an extended time on the job, they are at high risk for carpal tunnel syndrome, a disabling condition of the hand.

Noise. Although little population-based data are available, as much as 55% of farmers older than 50 may have clinically significant hearing impairment. Hearing impairment related to noise generated by farm equipment develops early in life. Rural students have a 2.5 times greater hearing loss than urban students and that discrepancy increases with age and number of years worked in farming. Farmers and farm family members are exposed to excessive noise from equipment used on the farm, including tractors, grain dryers, combines, bush hogs, and chain saws.

Noise induced hearing loss occurs with continued exposure to high levels of noise; it is cumulative and irreversible. Noise-induced hearing loss results from the destruction of the cochlear hair cells in the inner ear. There are two types of hearing damage caused by excessive noise. Acous­tic trauma occurs when the ears are exposed to a single sudden sound above 140 dB(A) (decibels measured on the A scale, which incorporates weighting that takes into account the ear’s varying response to sounds of different frequencies) and the sensory cells are permanently dis­lodged and destroyed. Gunshot blasts or explosions can cause acoustic trauma.

Prolonged exposure to noises above 85 dB(A) can result in damage, though not necessarily permanent, to the cochlear nerve cells. Permanent damage to hearing occurs when exposure to excessive noise levels continues and the nerve cells are not given sufficient time to recover. There is no universal agreement on recovery duration.

There is ample evidence that the damage is insidious, usually beginning at a young age, and in the long run, usually severe enough to affect a person’s ability to hear and understand speech. Some evidence suggests that chemicals such as solvents and pesticides can interact with occupational noise exposure, resulting in a greater risk for hearing loss than noise exposure alone. This mix­ture of exposures may be particularly harmful for young farmworkers (Perry and May, 2005).

Stress. There is little doubt that farming is one of the most stressful occupations in both developed and developing countries. Both farm workers and farm family members are exposed to the economic pressures of their family livelihood, the future of which remains precarious at best. The influence of stress is manifested by psychologi­cal or emotional disturbance such as alcohol abuse among family members, as well as by the creation of insecure working conditions.

Being unmarried, having negative life events within the past year (legal problems, substantial income decline, and loss of something of sentimental value), and lower perceived general health status have been identified as significant risk factors for depressive symptoms among male farmers in the United States.

Farm workers in general have high rates of depression. Extreme poverty and hardship, the stress of job uncer­tainty and frequent moves, and social stigmatization and isolation are contributing factors. This is true for children and youth as well. Studies have also linked depression in workers to long hours of work in high-intensity, low-skilled jobs, precisely the kind of labor undertaken by farm workers.

Having one’s livelihood controlled by the uncertainty of the weather and the agricultural market combined with the social isolation often experienced by rural inhabitants increase the risk for psychological distress. Rural areas of China and Sri Lanka, for example, have seen an increase in suicides among subsistence farmers, many of whom are using toxic farm chemicals to poison themselves. Identi­fying symptoms of psychosocial stress in farmers requires history taking and consultation to determine current social and economic conditions in the family.

Depressive symptoms are expressed differently in men and women. Knowing that adult farm owners and farm workers are at higher risk for psychological disturbance should alert health-care providers and public health practitioners to the need for outreach to these high-risk groups. Because health-care providers are usually the first mental health contact for rural residents, they play an important role in the early identification of psychological distress in farm­ers, farm workers, and their families.

Sanitation. Agricultural health clinicians have identified hygiene as being key in preventing bacterial infections from animals and dermatoses caused by chemical contamination. How­ever, farmers themselves may forego the minimum sani­tation requirements when working in fields as a means of saving time and effort or because water is simply not available.

Regulations in the United States illustrate how basic public health protections may not be in place for agricultural workers. Access to clean drinking water, water for hand washing, and toilet facilities are the minimum sanitation requirements imposed on farms by the Occu­pational Safety and Health Administration (OSHA), the occupational regulatory agency in the United States.

Even these minimal requirements, however, may be ignored by growers and by the farm labor contractors who bring in workers. Furthermore, labor laws prohibit enforcement of these regulations on farms with ten employees or less, essentially exempting small farms. An estimated 95% of all U.S. farms fall under this exemption. Health-care pro­viders and public health practitioners should consider the multiple sources of contamination in the farm environment and consider hygiene as having a role in sources of infections, especially of the skin.

Heat. Heat illnesses can lead to death or brain damage and are an ever-present danger for field workers. In the United States alone, there are approximately 500 deaths annually from heat illnesses. Risk for heat stress during the growing season is particularly acute, especially during haying and harvesting. It is recommended that workers laboring under hot weather conditions drink a minimum of 8 oz of water every half hour.

Very high heat or humidity increases the amount of recommended water, so that, for example, a person working in 90 °F heat under a full sun should drink 8 oz of water every 15 min. Ensuring sources of fresh water are abundant is critical to maintain workers’ hydration needs. Excessive sun exposure places farmers at risk for future skin malignancies and must be prevented with proper head and body covering, which can also increase the risk of heat stress from too much clothing. Keeping farmers hydrated, protected from the sun, and ensuring a minimum of 10 min of break time during each hour can reduce the risk of illnesses from overexposure to heat and sun.