Safety and Health Issues in Meat Processing Industry

Introduction: Overview of Risks in the Meat Industry

In the meat processing industry, health and safety issues are of vital importance, given the several risks arising from microbial contamination of meat and the occupational hazards faced by workers. Past experience has shown that microbial reproduction in meat and meat products can reach alarming proportions, spreading across countries and even continents. The infamous mad cow disease and foot-and-mouth disease in cattle rattled the British meat industry for a considerable period, resulting in loss of image, consumer confidence, and erosion of profits. North America's main problem is the widespread prevalence of Escherichia coli in meat, more commonly known as hamburger disease. Meat is highly susceptible to attack by bacteria and viruses, and hence there is a constant need to address this risk. When microbial activity sets in, the quality of meat is affected and the consumer suffers from food poisoning or infection.

According to Dr. Linda Saucier of Canada's Food Research and Development Centre (FRDC), every year about 5 to 10% of the global population is afflicted by some kind of food poisoning, of which one in three cases is due to contamination in meat or meat products (Brodeur, Agriculture and Agri-food Canada). Since animals brought for slaughter carry microbes in one form or another, the risk of infection is invariably high during meat processing. Another major issue in the meat industry is the safety and health of workers carrying out processing operations. Meat processing involves a great deal of physical activity and the compulsion to work in environmentally hostile conditions. The nature of the work requires workers to manually handle heavy equipment on a repetitive basis, which can lead to serious physical injuries and illnesses. Unsafe working conditions lead to lower productivity and increase the risk of losses. Lack of hygiene and safety in meat processing units can lead to major quality problems in the final product. Once meat shows signs of infection, it faces market rejection, cannot be sold, and may have to be destroyed.

Sources of Meat and Pre-Slaughter Handling

The main sources of meat are cattle, pigs, sheep, and poultry. Cattle include cows, calves, and bullocks. Cow beef is manufactured from cows that are typically near or past their useful period of milk production; such cows are generally 5–8 years old, although regulations in the UK do not allow extraction of meat from cattle aged more than 30 months (Ranken, 2000, p. 23). When the population of male and female calves exceeds the milk cattle demand, the surplus is diverted for meat manufacture. Bullock meat is manufactured from breeds weighing 450 kg or more. Pig meat comes from bacon pigs, heavy hogs, continental breeds, and boars. Pig meat is valued for its rich fat content and is used for making fresh pork, bacon, sausages, and pie meat. In poultry, chicken is the main source of meat, coming from hens past their egg-laying period, broilers suitable for grilling, and broiler breeder hens. Turkey meat is also popular, characterized by its heavy weight and high meat yield.

The risk of microbial infection is present from the stage of rearing animals onward. Handling of animals in the period before slaughter can determine the quality and hence the commercial value of the finished meat. Poor pre-slaughter handling — such as rough transportation and cramming large numbers of animals into small cages — may lead to unwarranted stress and agitation. Stress leads to softening of pig meat and dark cuts in cattle, adversely affecting quality. Under stress, birds and animals tend to defecate more, posing risks of contamination. Stress has been shown to promote the growth of salmonella in pigs and the shedding of E. coli in cattle (Varnam and Sutherland, 1995, p. 44).

Slaughtering Operations and Associated Hazards

The Health and Safety Executive (HSE) of the UK has identified meat and poultry slaughtering as the major contributors to worker injury in the UK. Over a three-year period, injuries per 100,000 workers were 3,845 for meat slaughtering, 2,943 for poultry slaughtering, and 2,081 for meat and poultry products — rates far exceeding the entire manufacturing industry average of 1,190 injuries per 100,000 workers over the same period (Health & Safety Executive). This is striking evidence of the high risk of injury faced by workers in the meat processing industry. The methods employed in slaughtering have an impact not only on the quality and quantity of meat, but also on the safety of workers and the well-being of ultimate consumers. A typical slaughterhouse receives animals from a variety of sources, and the risk of disease and microbial infection is therefore always present. Symptoms of certain diseases — such as rabies or tetanus — may be more evident in live animals than in the carcass. Certain infections must be detected without delay, as they may reach epidemic proportions if left unchecked. Examples include anthrax, caused by the bacterium Bacillus anthracis, which produces infective spores capable of spreading rapidly in animals and humans with potentially fatal results, and foot-and-mouth disease, caused by a virus that creates blisters in the mouth and feet, reducing the efficiency of body organs.

Before slaughtering, animals are generally subjected to the process of stunning, wherein they are immobilized to facilitate quick severing of blood vessels. Stunning spares animals from feeling the pain of being killed. Animals are stunned in three ways: use of a mechanical instrument such as a captive bolt pistol, passage of electric current through the brain, or induction of unconsciousness through anaesthetic gases such as carbon dioxide. In each method, the objective is to traumatize the brain so that the animal becomes unconscious and can be killed without resistance. However, not all meat processors follow stunning practices. The methods adopted by Jews, Muslims (halal meat), and Sikhs do not incorporate stunning prior to slaughter (Warriss, 2000, p. 56). Animals are generally killed by a single stroke of the sword, which exposes workers to the risk of injuries from repeatedly handling heavy implements while dealing with conscious animals capable of reacting.

Pithing is one of the commonly used processes in slaughtering adult cattle. Its objective is to destroy the brain and spinal cord so that the animal does not react involuntarily during slaughter. A long flexible rod — the pithing cane, made of plastic or stainless steel — is inserted into the skull through a hole created by a captive bolt pistol and manipulated to damage brain tissue. The cane is also slid down the vertebral canal to destroy the spinal nerves. Pithing poses grave risks: opening the internal parts of the animal creates an easy target for microbial infection, and with blood circulation still functioning at the time of brain destruction, microbes can spread rapidly to other organs. Another approach involves severing the spinal cord at the point where it enters the skull using knives (Jones, 1992, p. 12). While this method may cause instant paralysis, it does not render the animal unconscious and is therefore generally not favored. In modern meat processing, the trend is to discard pithing, which reassures consumers that the risk of microbial contamination is greatly reduced.

In another operation, known as sticking, the animal's arteries and veins are cut to ensure brain death. Knives are used, and immediately after cutting, bleeding results from the fractured vessels. The blood exposed at the wound site carries a risk of infection from external sources. Repeated sticking operations expose workers to the risk of injuries and cumulative traumatic disorders (Jones, 1992, p. 13).

Carcass dressing is another major area of occupational risk. The outer skins of even healthy animals can be contaminated with dirt and bacteria, a problem particularly prevalent in animals with abundant hair, as hair layers can also harbor insects and flies that carry microbes. The primary objective of carcass dressing is to remove the outer skin, hair, and other non-edible parts in order to free the meat of infection. Traditionally, carcass dressing was performed with the animal laid on the floor or on a cradle; it is now done with the carcass hanging by its hind legs from an overhead rail system, which has greatly improved hygiene but does not eliminate the risk from microbes present in skin or hair. Workers face similar risks in poultry processing. After stunning, the blood vessels in the bird's neck are cut either manually or with an automatic rotating knife, and feathers are removed before the meat is prepared, to reduce carcass contamination (Jones, 1992, p. 15).

One of the major risks in poultry processing is microbial contamination arising from accidental cuts and wounds sustained during operations. Even small infections can rapidly spread across whole populations of carcasses, so workers must exercise considerable caution. Workers themselves are at risk of exposure to harmful bacteria. Following slaughter, carcasses and viscera are subjected to post-mortem inspection to ensure that the meat is fit for human consumption. Tissues and organs are examined by visual inspection, palpation, and incision. Routine incision of lymph nodes is commonly performed to detect disease. It is well established that pneumonia and tuberculosis produce characteristic lesions, and that parasitic diseases caused by tapeworms and ringworms are often concentrated in the liver, muscles, and heart. These microbes continue to thrive, especially in undercooked meat, and can easily enter the human system. Personnel conducting post-mortem inspection are therefore directly exposed to the risk of microbial attack.

Butchering presents yet another area of concern. Meat is butchered into smaller portions for sale at retail outlets, requiring workers to repeat cutting actions many times in the course of their work. Butchering can therefore lead to injuries, trauma disorders, and related illnesses. Butchers are exposed to meat in an open state and are easily prone to bacterial attack if the meat is already infected. Butchering can also affect meat quality depending on the manner of cutting, timing, and choice of knives used. Due to the nature of the work, butchering outlets often tend to have poor sanitary and hygienic conditions unless there is regular maintenance and proper housekeeping. Workers are constantly exposed to potentially infectious conditions and, if already infected with harmful bacteria, may contribute to the spread of infection to both colleagues and the meat being handled.

Conclusion

It is clear that workers in the meat processing industry are exposed to a multitude of risks. The demand for greater physical exertion and the repetitive nature of work are leading to injuries, cumulative traumatic disorders, and related illnesses. Meat processing and packaging is becoming increasingly mechanized, but many health and safety risks continue to confront workers. Unsafe conditions and practices in the workplace affect the ultimate quality of meat in one way or another. After the alarming outbreaks of microbial contamination — such as mad cow disease in recent years — consumers are justifiably wary of the quality of the meat they purchase. It is therefore critically important that the quality and wholesomeness of meat are preserved and that the best possible product is offered to consumers.

If this objective is to be realized, workers must be educated and trained on the importance of safety and hygiene in meat processing operations. Employers have the responsibility to provide an ergonomic workplace that motivates workers to perform at their best — an outcome that benefits both consumers and the company. Robust regulatory frameworks, rigorous application of tools such as HACCP, and continued investment in advanced processing technologies collectively represent the path toward a safer, higher-quality meat industry.

American Meat Industry Fact Sheet: "Worker Safety in the Meat and Poultry Industry." (2002). Available at www.meatami.com/content/presscentre/factsheets_infobits/FactSheetWorkerSafety.pdf. Accessed 11/28/2003.

Brodeur, C. (n.d.). Agriculture and Agri-food Canada — "Meat Safety: The War on Bacteria." Available at http://www.res2.agr.gc.ca/orda/pubs/art8_e.htm. Accessed 11/28/2003.

Cannon, J. E., et al. (1996). Pork chain quality audit survey: Quantification of pork quality characteristics. Journal of Muscle Foods, 7, 56–62.

Chesworth, N. (1997). Food hygiene auditing. Blackie Academic & Professional, London.

Codex Alimentarius Commission. (1993). HACCP guidelines: Guidelines for the application of Hazard Analysis Critical Control Point System (Supplement 1).

Crossland, W. J. (1997). HACCP and factory auditing. In N. Chesworth (Ed.), Food hygiene auditing. Blackie Academic & Professional, London.

Health & Safety Executive. Food manufacture: Slaughtering meat, poultry and fish processing. Available at www.hse.gov.uk/food/slaughter.htm. Accessed 11/28/2003.

Health & Safety Executive. (1997). Health and safety priorities in the meat processing industry: Food information sheet no. 15. Available at www.hse.gov.uk/pubns/fis15.pdf. Accessed 11/28/2003.

Heitzmann, R. J. (1996). Residues in meat. In Meat quality and meat packaging. ECCEAMST, Utrecht.

Johnson, D. R. (1994). Guide to U.S. food safety law. Thompson Publishing Group, New York.

Jones, J. M. (1992). Food safety. Eagen Press, St. Paul.

Middlekauff, R. D. (1989). Regulating safety of food. Food Technologist, 43(9), 296–307.

Morgan, J. B., et al. (1991). National beef tenderness survey. Journal of Animal Science, 69, 3274.

Ranken, M. D. (2000). Meat product technology. Blackwell Science, UK.

Varnam, A., & Sutherland, J. (1995). Meat and meat products: Technology, chemistry and microbiology. Chapman & Hall, London.

USDA Report. Worker safety issues related to Advanced Meat Recovery. Available at www.fsis.usda.gov/OPPDE/rdad/FRPubs/98-027R/WorkerSafetyIssuesRelatedtoAMR.pdf. Accessed 11/28/2003.

Warriss, P. D. (2000). Meat science: An introductory text. CABI Publishing, Oxon.