Assuming a world population of 5 billion, between one-quarter and one-half of a million people die each day. Many of the dead are infants or children, but eventually everyone who is born will also die. Despite the diversity in culture and religious beliefs surrounding death, the bodily remains of each person must be disposed of. In general, the two main methods of disposing of human remains consist of burial and cremation. Both of these disposal methods often have been applied to the untreated human remains. Many cultures, however, have developed funeral rites that prescribe some treatment of the dead body. Simpler rites may include the washing of the external surface with herbs and spices to slow or mask the onset of decay and the smell associated with dead tissue. More sophisticated rites include intrusive procedures such as embalming and removal of internal organs. Embalming usually involves replacement of blood with an embalming or preserving fluid. The Egyptians were among the first culture to develop and practice embalming of the dead. Embalming has been extensively practiced in the twentieth century throughout Western Europe and North America. Embalming may be followed either by burial or cremation. Outside of Western Europe and North America, burial or cremation is usually not preceded by embalming.
The preparation and burial of a deceased person can involve many processes, including:
- washing the surface of the body with various preparations
- dressing the body in burial clothes
- autopsies, in certain circumstances, which involve intrusive procedure, such as dissection and analysis of blood and body tissues
- embalming and removal of internal organs
- application of cosmetics to cover up visible damage if the body is to be viewed
- transporting the body to place of burial or cremation
- lifting of body and casket, and lowering it into the grave
- digging and filling of the grave
- possible exhumation of the body and subsequent autopsy.
Three types of hazard are always associated with the handling of deceased humans: microbial, psychological and ergonomic. A fourth type of hazard - chemical exposure - is introduced when embalming is performed. In the United States many states have enacted laws that require a body to be embalmed if the deceased person will be viewed in a open casket.
Death is often caused by disease. After death the germs that caused the disease may continue to live in the deceased person and can infect the people handling the dead body.
Contagious diseases such as the plague and smallpox have been spread by improper handling of victims who died from the diseases. The route of exposure must be considered when evaluating the microbial hazard associated with the handling of dead bodies. Many diseases are spread by touching a source of contamination and then introducing that disease-causing organism, or pathogen, to one’s mucous membranes by rubbing the eyes or nose, or by ingesting the pathogen. Some diseases can be contracted simply by inhaling the pathogen. Inhalation can be a special hazard during exhumation, when the remains are dry, or during procedures that aerosolize parts of the human body, such as sawing through the bone of a deceased person. The contagion of diseases is further exacerbated when procedures with sharp instruments are used in funeral rites. Such practices introduce the possibility of parenteral exposure.
Microbial hazards can be classified in many different ways, including the type of disease-causing organism, the type of disease, the severity of the disease and the route of infection. Perhaps the most useful way of discussing microbial hazards encountered by funeral workers is by route of infection. The routes of infection are ingestion, inhalation, touch or surface contact and parenteral, or puncture of a body surface.
Ingestion as a route of exposure can be controlled by proper personal hygiene - that is, always washing hands before eating or smoking, and by keeping food, drink or any object that will be put in the mouth (such as cigarettes) out of areas of possible contamination. This is important for controlling chemical exposure as well. In addition to careful personal hygiene, wearing impermeable gloves when handling the dead can reduce the probability of infection.
Inhalation exposure occurs only when disease-causing organisms become airborne. For funeral workers the two primary ways that pathogens can become airborne are during an exhumation or during autopsy procedures in which a saw is used to cut through bone. A third possibility of aerosolizing a pathogen - tuberculosis, for example - is when air is forced out of the lungs of a corpse during handling. Although the epidemics of the past have included plague, cholera, typhoid, tuberculosis, anthrax and smallpox, only the organisms causing anthrax and smallpox appear capable of surviving any length of time after burial (Healing, Hoffman and Young 1995). These pathogens would be found in any of the soft tissues, not the bones, and particularly in soft tissues that have become mummified and/or dried out and friable. The anthrax bacterium can form spores that remain viable for long periods, especially under dry conditions. Intact smallpox viruses taken from the tissues of bodies buried in the 1850s were identified under the electron microscope. None of the viruses grew in tissue culture and they were deemed to be non-infective (Baxter, Brazier and Young 1988). Smallpox virus has remained infective, however, after 13 years in dry storage under laboratory conditions (Wolff and Croon 1968). An article appearing in the Journal of Public Health (UK) during the 1850s reports concern about smallpox infectivity from remains buried two hundred years earlier in Montreal, when smallpox was widespread in the New World (Sly 1994).
Perhaps a more probable source of inhalation exposure during exhumation are fungal spores. Whenever old material of any sort is disturbed, protection against the inhalation of fungal spores should be provided. Disposable high efficiency particulate (HEPA) respirators, developed primarily for protection against tuberculosis and lead dust, are quite effective against fungal spores as well. In addition to microbial concerns, the possibility of exposure to wood dust and/or lead needs to be evaluated before any exhumation proceeds.
The primary route of infection for tuberculosis is inhalation. The incidence of tuberculosis has increased during the last quarter of the twentieth century, primarily due to decreased public health vigilance and the emergence of bacterial strains that are resistant to several groups of antibiotics. A recent study conducted at Johns Hopkins School of Public Health (Baltimore, Maryland, US) indicates that 18.8% of embalmers demonstrated positive results to tuberculin skin tests. Only 6.8% of people employed in the funeral business who are not embalmers demonstrated positive results to the same test. The lower rate of reactivity is similar to the general public (Gershon and Karkashion 1996).
Hepatitis B virus (HBV) and the human immunodeficiency virus (HIV) are infective if they come in contact with mucous membranes or are introduced into the bloodstream through a cut or puncture. A study of funeral service practitioners in Maryland indicated that 10% had a mucous membrane exposure within the past 6 months and 15% reported a needle stick within the past 6 months (Gershon et al. 1995). Other US studies reported that between 39 and 53% of morticians had a needle stick within the past 12 months (Nwanyanwu, Tubasuri and Harris 1989). In the United States, the reported prevalence of HBV is between 7.5 and 12.0% in unvaccinated funeral directors, and 2.6% or less in vaccinated funeral workers. The reported vaccination rate varies between 19 and 60% of morticians in the United States. Although there is a vaccine for HBV, there is currently no vaccine for HIV.
HIV and HBV are infective only when the virus comes into contact with the mucous membranes or is introduced into the bloodstream of another human. The virus is not absorbed through intact skin. Mucous membranes include the mouth, nose and eyes. These viruses can be introduced into the bloodstream through a cut or abrasion in the skin, or by puncturing or cutting the skin with an instrument that is contaminated with the virus. Hands that are cracked due to dryness or a hangnail may provide routes of entry for these viruses. Therefore, to prevent transmission of these diseases it is important to provide a barrier impermeable to body fluids, to avoid splashing contaminated fluids on the eyes, nose or mouth, and to prevent puncturing or cutting the skin with an instrument contaminated with HIV or HBV. Use of latex gloves and a face shield can often provide this protection. Latex gloves, however, have a limited shelf life depending on the amount of sunlight and heat to which they have been exposed. In general, the latex should be stress tested if the gloves have been stored for more than a year. Stress testing involves filling the glove with water and observing if any leaks develop during a minimum of two minutes. Some countries in the West, such as the United States and Great Britain, have adopted the idea of universal precautions, which means that every corpse is treated as if it were infected with HIV and HBV.
In many cultures the family of the deceased prepares the body of their dead relative for burial or cremation. In other cultures a specialized group of individuals prepares the bodies of the dead for burial or cremation. There is a psychological effect on the living when they are involved in handling dead bodies. The psychological effect is real regardless of the procedures used in the funeral rites. Recently there has been an interest in identifying and evaluating the effects of performing funeral rites on those who actually perform them.
Although the psychological hazards of being a professional funeral worker have not been extensively studied, the psychological effects of dealing with the human remains of traumatic death have been recently analyzed. The main psychological effects appear to be anxiety, depression and somatization (the tendency to report physical ailments), as well as irritability, appetite and sleep disturbances, and increased alcohol use (Ursano et al. 1995). Post-traumatic stress disorder (PTSD) occurred in a significant number of individuals who handled the victims of traumatic deaths. Immediately after a disaster in which human remains were handled by rescue workers, between 20 and 40% of the rescue workers were considered to be in a high risk category, as demonstrated by psychological testing, but only about 10% of the rescue workers were diagnosed with PTSD. The psychological effects were still present in rescue workers one year after the disaster, but the incidence was greatly reduced. Adverse psychological effects, however, have been detected in individuals several years after the traumatic event.
Many of these studies were performed on military personnel. They indicate that generalized stress rates are higher in inexperienced individuals who were not volunteers, and that there was an increased incidence of stress indicators up to one year after a traumatic incident. Empathy or self-identification of the mortuary worker with the deceased appeared to be associated with an increased level of psychological stress (McCarroll et al. 1993; McCarroll et al. 1995).
One study evaluated the causes of death in 4,046 embalmers and funeral directors in the United States between 1975 and 1985, and reported a proportionate mortality ratio (PMR) of 130 for suicide. The PMR is a ratio of the actual number of suicides in the embalmers and funeral directors divided by the number of suicides that would be expected in a group of individuals comparable in age, race and sex who are not embalmers or funeral directors. This ratio is then multiplied by 100. The purpose of this study was to assess the risk of cancer in morticians, and the suicide statistic was not elaborated any further.
A deceased human adult is heavy and usually must be carried to a designated place of burial or cremation. Even when mechanical means of transportation are used, the dead body must be transferred from the place of death to the vehicle and from the vehicle to the burial or cremation site. Out of respect for the dead person, this transfer is usually performed by other humans.
Morticians are required to move corpses many times during the course of body preparation and funerals. Although there were no studies found that addressed this issue, low-back pain and injury is associated with prolonged repetitive lifting of heavy objects. There are lifting devices available which can assist with these types of lifts.
Embalming procedures introduce a number of potent chemicals into the workspace of funeral workers. Perhaps the most widely used and toxic of these is formaldehyde. Formaldehyde is irritating to the mucous membranes, the eyes, the nasal lining and the respiratory system, and has been associated with mutagenic cell changes and the development of cancer, as well as occupational asthma. During the past several decades the occupational exposure level associated with no adverse effects has been consistently lowered. Current 8-hour time-weighted average permissible exposure limits range from 0.5 ppm in Germany, Japan, Norway, Sweden and Switzerland to 5 ppm in Egypt and Taiwan (IARC 1995c). Formaldehyde levels between 0.15 and 4.3 ppm, with instantaneous levels as high as 6.6 ppm, have been reported for individual embalmings. An embalming typically takes between 1 and 2 hours. Additional formaldehyde exposure is associated with the application of embalming creams and drying and hardening powders, and during spills.
Rats that have been chronically exposed to 6 to 15 ppm of formaldehyde (Albert et al. 1982; Kerns et al. 1982; Tobe et al. 1985), or repeatedly exposed to 20 ppm for 15-minute periods (Feron et al. 1988), have developed nasal carcinomas (Hayes et al. 1990). The IARC reports limited epidemiological evidence for an association between formaldehyde exposure in industry and the development of human nasal and pharyngeal cancers (Olsen and Asnaes 1986; Hayes et al. 1986; Roush et al. 1987; Vaughan et al. 1986; Blair et al. 1986; Stayner et al. 1988). Several studies of morticians, however, have reported an increased incidence of leukaemias and brain tumours (Levine, Andjelkovich and Shaw 1984; Walrath and Fraumeni 1983). In addition to the carcinogenic effects, formaldehyde is irritating to the mucous membranes and has been considered a strong sensitizer in the development of adult-onset asthma. The mechanism or mechanisms by which formaldehyde precipitates asthma are even less well characterized than its role in the development of cancer.
Other potentially toxic chemicals used in embalming fluids include phenol, methanol, isopropyl alcohol and glutaraldehyde (Hayes et al. 1990). Glutaraldehyde appears to be even more irritating than formaldehyde to the mucous membranes, and affects the central nervous system at levels well above 500 ppm. Methanol also affects the central nervous system and, in particular, the vision system. Phenol appears to affect the nervous system as well as the lungs, heart, liver and kidneys, and is absorbed quite rapidly through the skin. Our understanding of the toxicology of, and our ability to perform risk assessment for, exposure to multiple chemicals simultaneously are not sufficiently sophisticated to analyse the physiological effects of the mixtures to which embalmers and funeral directors are exposed. Blair et al. (1990a) thought that the increased incidence of leukaemias and brain tumours reported in professional, but not industrial, workers was a result of exposure to chemicals other than formaldehyde.
Recent advances in the design of dissecting tables indicate that local downdrafting of vapours significantly reduces the exposure of individuals working in the vicinity (Coleman 1995). Wearing gloves while performing procedures that require skin contact with embalming fluids and creams also reduces the hazard. There has been some concern, however, that some of the latex gloves on the market may be permeable to formaldehyde. Therefore, protective gloves should be selected carefully. In addition to the immediate concerns about the hazards of formaldehyde exposure, evidence has been accumulating that leachate from cemeteries may lead to formaldehyde contamination of groundwater.
Exhumation of bodies may also involve chemical exposures. Although used sporadically for centuries, lead was commonly used to line coffins beginning in the eighteenth and continuing into the nineteenth century. Inhalation of wood dust is associated with respiratory problems, and fungus-contaminated wood dust is a double-edged sword. Arsenic and mercury compounds were also used as preservatives in the past and could present a hazard during exhumation.