Risky Business: Potential Hazards in the Archaeological Investigation of Historic Cemeteries
Paper presented at the 5th Annual Council for West Virginia Archeology Spring Workshop
Warning: Images may be disturbing to some viewers
The excavation of any archaeological site is conducted with the knowledge that potential dangers exist, and precautions are taken to alleviate the risk of harm to workers. Historic cemeteries offer a whole new genre of potential hazards, including embalming chemicals, heavy metals used in coffin and casket construction, and preserved human flesh that could be teeming with disease-causing organisms. This paper will describe in detail the types of hazards that could be encountered during the excavation of an historic cemetery, and provides a short overview of appropriate precautions to ensure a safe working environment. The three main types of hazards potentially associated with historic cemetery excavations are biological (infectious, rickettsial, and viral diseases), chemical (including embalming fluids and coffin materials), and physical (such as working in grave shafts).
Biological Hazards
Numerous infectious bacterial and viral diseases affected historic populations, many of which were catastrophic to 18th, 19th, and early 20th century populations in the United States. Although it is not likely that vestiges of these diseases could have survived over the years in an historic grave setting, it is possible, especially under certain circumstances, such as burial in a metal coffin or in permanently frozen ground. It is highly unlikely we will ever encounter a frozen historic corpse in our temperate climate, but it is possible, if not likely, that intact metal caskets will be found. (slide 2 and slide 3) The first patent for a metal casket was granted in the late 1840s and metal caskets had a period of popular use until the early 20th century. They have been identified during cemetery excavations across the eastern U.S., including the states of Illinois, Indiana, Kentucky, Tennessee, and Virginia. Metal caskets containing preserved human remains have been encountered in cemeteries located in Indiana and Tennessee. Nawrocki et al. (1996) reported on two metal caskets at the 19th century Rhoads Cemetery (12Ma777) in Marion County, Indiana. Pinkish-gray brain material was noted in the cranial cavities, fragments of friction foot skin (and three toenails) were identified, and what was probably rehydrated tissue and decomposition fluid was found in the two sub-adult interments (Nawrocki et al. 1996:11). In the late 1970s, Bass (1984) investigated an interment that, because of the presence of preserved soft tissue (including recognizable intestines), was at first thought to have been buried up to one year prior. It was later realized, however, that the grave was that of a young man who died during the Civil War. He was embalmed and buried in a metal casket 113 years prior to the investigation (Bass 1984). Although the risk of acquiring disease from human remains decreases rapidly with time and decomposition and loss of soft tissue (Ubelaker 1995:46), if an intact metal casket is encountered, it is possible that any communicable disease afflicting the deceased in life, and possibly causing his or her death, could be present in preserved soft tissues.
Bacterial diseases were prevalent in most North American populations prior to the 20th century and were probably the leading cause of death during that time. Anthrax, tetanus, and tuberculosis are resilient bacteria, and special concern about exposure may be warranted with these diseases. Sledzik (2000:73) notes that anthrax spores can last for years, Ubelaker (1995:46) states that tuberculosis is especially hardy, and the United States National Library of Medicine (USNLM) (2003) claims that tetanus can remain infectious for more than 40 years.
(slide 4) Anthrax (Bacillus anthracis) can be contracted cutaneously (through cuts or scrapes in the skin), through inhalation (the terrorist threat), and through ingestion (Lew 1995, cited in Sledzik 2000:73). When contracted through the skin, a small blister emerges around three days after exposure. The pimple fills with fluid, becomes black from hemorrhage, and ulcerates. Edema of the affected limb or other body part usually accompanies the blister. With antimicrobial drugs, death rarely occurs from cutaneous anthrax (Sledzik 2000:73). Although humans are less susceptible to anthrax than most animals, large inhaled doses of spores can produce serious pneumonia, and lead to devastating blood-borne infection. Usually two or three days after exposure, the victim has flu-like symptoms with aches and pains, fever, increasing cough, and shortness of breath. Then the symptoms progress rapidly to severe cough, collapse and respiratory failure, often with a fatal outcome (Crist 2000:90). Respiratory anthrax is hard to transmit person-to-person, though, because the bacteria stay lodged in the main lesions of the lungs and lymph nodes (they are not excreted in large quantities in a cough or sneeze). Cipro (Ciprofioxacin) is an antibiotic used to treat bacterial infections and is approved for the inhaled form of anthrax after exposure. Without treatment, respiratory anthrax is almost always fatal (Sledzik 2000:73). After the terrorist attacks of September 11, 2001, letters containing anthrax spores were received in New York, Florida, and Washington D.C., resulting in at least four deaths from inhaled anthrax, although most exposed individuals recovered with the use of Cipro.
(slide 5) Tetanus (Clostridium tetani) bacteria affect the central nervous system, sometimes resulting in death. Spores live in soil and animal feces and can remain dormant for many years. They can be infectious for periods longer than 40 years (USNLM 2003). Infection begins when spores are introduced into an open wound, where they germinate and release active bacteria that produce neurotoxins. These neurotoxins inhibit nerve transmission from the spinal cord to the muscles, causing severe muscle spasm. The contractions can be so powerful that they tear muscles or cause vertebral compression fractures. This disease often begins with mild spasms of the masseter muscles in the jaw (lockjaw), neck muscles, and facial muscles, continuing with stiffness in the chest, back, abdomen, and laryngeal muscles (affecting breathing). All of this is followed by muscular seizures (Dire 2003; Todar 2002). Without treatment, one in three people with tetanus die, and newborns with untreated tetanus die two out of three times; with treatment, less than 10% of patients die. Worldwide, tetanus currently has a mortality rate of over 50% (Crist 2000:94). Incubation lasts from two to 50 days, with five to ten days the average. In the United States, there are about 100 cases of tetanus per year, most of which are in unimmunized individuals or those whose last immunization was no longer current. Galloway and Snodgrass (1998) suggest individuals working with human remains get a booster shot every two years and immunization after skin injuries.
(slide 6) Tuberculosis (Mycobacterium tuberculosis), called consumption historically, is a chronic, recurrent infection most common in the lungs, but can affect any organ, including the skeletal system (Crist 2000:94). The disease has been around for thousands of years and traditional treatment included drinking potions whose ingredients included garlic and dog fat, inhaling smoke from burning cow dung, and taking long sea voyages to exercise the chest with “extended vomiting” (Lung Association 2003). In the 19th century, other treatments emerged, including staying in airtight rooms while wrapped in a blanket near a hot stove. The end of the 19th century saw the beginning of the use of sanatoriums, which touted fresh country air as a magical elixir. Also at these sanatoriums, which tended to be rather posh resorts, heliotherapy made its debut. It was believed that the sun, and later Vitamin D, could help kill the non-pulmonary TB bacteria. Cod liver oil was eventually sold as liquid sunshine (Lung Association 2003). Because of its infectious nature and long chronic course, tuberculosis impacted the health and lives of many families without regard to social or financial standing. Until the 1800s, no treatment for tuberculosis existed and the route of transmission of the disease was not known. In the first half of the 19th century, tuberculosis was responsible for one of every five deaths (Rothman 1995). The tuberculosis of concern here is the pulmonary form, which is the most common. Initial infection may be followed by an asymptomatic latency period extending for several years. In pre-antibiotic times, 50% of cases resulted in death (Crist 2000:94). Symptoms of the disease include dry cough that progressively becomes more productive, followed by rupture of the lung. Inflammatory reactions within highly infected lung tissue can also occur. In longer-term cases, lesions of other soft tissue organs (kidneys, brain, intestines, liver) may also occur. A potential epidemic of drug-resistant tuberculosis has emerged, particularly affecting immuno-suppressed individuals (Crist 2000:95).
(slide 7) Scarlet fever, or scarlatina, (Streptococcus pyogenes) is an acute streptococcal infection of the pharyngeal region (Crist 2000:92). Symptoms include sore throat, sore neck glands, fever, swelling of the tongue, convulsions, and a pink rash that results from the release of toxins from the bacteria that is irritative to the skin. The rash usually appears as a bad sunburn with tiny papules that first appears on the neck and face and spreads to the chest and back (Nemours Foundation 2003). If untreated, the infection can enter the bloodstream or progress to pneumonia (Crist 2000:93).
(slide 8) Syphilis (Treponema pallidum) is a systemic sexually transmitted disease that is characterized by years of latency with no symptoms (Crist 2000:93). The incubation period may vary from one to 13 weeks, but averages three to four weeks. Skin rashes usually appear within 4 to 12 weeks of infection and are most florid after three to four months, with lesions persisting months afterward. The bacteria attacks the CNS early in the infection and within two years the disease enters an asymptomatic latent stage that can last for years, with recurrent outbreaks of lesions occasionally. The late stage of the disease, from three to ten years after infection, is not contagious and is marked by disorders of the nervous and cardiovascular systems, ulcerations of the cranium, and necrosis of soft tissue in the face, genitals, and lower limbs. When left untreated, the disease produces destructive tumor-like masses called gummas (University of Illinois 2003). These occur in the skin and skeletal and nervous systems. Syphilis can cross the placental barrier in pregnant women, resulting in a variety of congenital defects. Before antibiotics, syphilis was treated with mercury, bismuth, and arsenic compounds. Penicillin was the first definitive treatment, and is still the drug of choice (University of Illinois 2003).
(slide 9) Typhus (Rickettsia prowazekii) is an acute severe disease characterized by prolonged high fever, headache, and a rash (Crist 2000:95). The disease is transmitted to humans through contact with the feces of body lice, often when a puncture wound (louse bite) is contaminated through scratching or the feces come in contact with the mucous membranes of the eyes or mouth (World Health Organization 1998). People confined to close, unsanitary quarters, such as refugee camps and prisoners of war, have often been afflicted with this disease. The incubation period for typhus lasts from one to two weeks. Toward the end of the first week of symptoms, small pink spots appear on the arms, legs, and trunk, which then spread across the rest of the body, except for the face, palms, and soles (Crist 2000:96). If untreated, circulatory collapse, anemia, edema, coma, and death may result.
(slide 10) Another bacterial disease that can be seen as a potential threat in historic cemetery excavations is cholera (Vibrio cholerae), an acute diarrheal disease caused by infection of the small intestine. Symptoms can be severe and include profuse watery diarrhea, vomiting, dehydration, and muscle cramps (Crist 2000:90). Rapid loss of fluids can lead to dehydration and shock, resulting ultimately in death (Centers for Disease Control [CDC] 2001). The bacteria are usually contracted through feces-contaminated drinking water or food, but brackish rivers and coastal waters can also contain cholera bacilli. Cholera bacteria produce a toxin that keeps the human body from absorbing liquids, and it is one of the most rapidly fatal illnesses known (Smoot 2002). Untreated individuals can die from severe dehydration in two to three hours. Although it can be life threatening, cholera is easily prevented with proper sanitation and easily treated with immediate replacement of fluids and salts and use of antibiotics. Cholera is potentially highly contagious, and is often spread by ingestion of water, seafood, and uncooked vegetables contaminated by the excrement of infected people. Cholera outbreaks are most common during warm months, and children are at the greatest risk for contracting the disease.
In the United States, cholera was first introduced by English immigrants ca. 1832. At that time, there was no preventative, no treatment, and no cure for the disease (Smoot 2002). Cholera epidemics struck repeatedly between 1832 and 1873 and became the world's first truly global disease in a series of epidemics and had become the most feared disease of the century. The disease struck so suddenly, a person could be in good health at daybreak and dead by nightfall. A common treatment for cholera in the United States up through the Civil War was the purgative medicine calomel, which was composed of mercury. The medicine may have cleansed the bowels, but at the same time it caused acute mercury poisoning resulting in tooth and hair loss and destruction of the patient’s gums and intestines (Smoot 2002).
(slide 11) Dysentery, referred to as flux or bloody flux during the historic period, is an inflamed infection of the large intestines caused by four types of Shigella bacilli (Crist 2000:91). Symptoms primarily include stomach pain and diarrhea, but fever, anorexia, bloody diarrhea, and vomiting may also occur (Crist 2000:91). Death may result due to severe dehydration and circulatory collapse. The bacteria are transmitted through ingestion of food and direct contact with personal items contaminated by the feces of infected individuals, although flies and mosquitoes may also spread the disease. As with typhus, this disease is common in close, unsanitary conditions and was common among soldiers in trenches during World War I and II. The incubation period is one to four days for adults, but may be sudden in children.
(slide 12) Diphtheria (Corynebacterium diptheriae) is an acute respiratory disease occurring primarily in children under the age of ten (Crist 2000:91). According to Crist (2000:91), the disease is especially virulent in the winter and is transmitted through direct contact with other infected people or their contaminated belongings. With infection, the bacterium multiplies in the throat, and a pseudomembrane of bacteria and necrotic tissue may form over the throat and tonsils, causing a sore throat (Methodist Health Care System 2003). This may also result in gradual closing of the airway (Crist 2000:91). Other symptoms include breathing difficulty, enlarged lymph glands, stridor (a shrill breathing sound), nasal drainage, swelling of the palate, low-grade fever, and malaise. Death is usually caused by cyanosis when the membrane obstructs breathing. The incubation period is one to four days. Although a vaccine for diphtheria was developed in the mid-20th century, the disease still affects third world populations and results in the death of one in ten individuals infected.
(slide 13) Bacterial pneumonia (Streptococcus pneumoniae) is an acute infection of the lung tissue and the usual mechanism of infection is inhalation of droplets from infected individuals. Bacterial pneumonia is most common in winter and the bacteria lodge in the lungs, initiating an inflammatory process where fluid accumulates in air cells. Onset is sudden, with a single chill episode followed by pain, labored breathing, cough, and fever to as high as 105 degrees Fahrenheit. In the most severe cases, the victim may experience shaking chills, chattering teeth, severe chest pain, and a cough that produces rust-colored or greenish mucus (American Lung Association 2003). Historically, pneumonia was one of the most prevalent killers, with only diarrheal diseases and tuberculosis causing more deaths (Crist 2000:92).
Viral diseases were also prevalent in most North American populations throughout the historic period. Viruses are completely dependent on living cells for reproduction. Although the anatomical structure of viruses make it unlikely that they could survive without living cells as hosts, they do have the potential to affect individuals excavating historic cemeteries.
(slide 14) Influenza, also known as the flu, attacks the respiratory tract and symptoms include fever, headache, exhaustion, dry cough, sore throat, malaise, myalgia, chills, pharyngitis, rhinorrhea, and body aches (University of Florida 1997). Most people who get influenza recover in one to two weeks, but some people develop life-threatening complications, such as pneumonia. The virus is spread when a person who has the flu coughs, sneezes, or speaks and sends flu virus into the air and others inhale it. A person with influenza is contagious one day before exhibiting any symptoms and up to seven days after symptoms start. The incubation period is one to four days. Evans and Kaslow (1997, cited in Crist 2000:97) suggest that the virus causing influenza (and those causing measles and chickenpox) lose their infectivity within several hours of the death of the host cell.
More people died during the influenza pandemic of 1918-1919 (up to 40 million) than were killed in World War I. It was the most devastating epidemic in recorded world history. This influenza outbreak, which began in small pockets across the world, ravaged the world and 1/5 of the total population was infected. The flu was most deadly for infants and children from birth to five years, adults from 20 to 40 years, and the elderly from 70 to 74 years of age, and around 500,000 Americans died (Kolata 1999). According to Billings (1997), one physician wrote that patients with seemingly ordinary influenza would rapidly develop the most vicious type of pneumonia that has ever been seen and later, when cyanosis appeared in the patients, it was simply a struggle for air until they suffocated. Several attempts have been made to isolate the particular virus responsible for the 1918-1919 influenza pandemic (Taubenberger 1999). Frozen corpses of military men buried in the tundra of Greenland were exhumed in the mid-1990s in an attempt to collect viable virus cells from their organs. Major safety precautions were made to avoid letting the virus loose again if any was found to be living (Taubenberger 1999). Luckily or not, none was.
(slide 15) Smallpox is probably the most significant potential health risk arising from the excavation of historic cemeteries. The smallpox virus has essentially been eradicated and the vaccination is generally no longer performed, thus the release of smallpox organisms could be catastrophic. The last outbreak in the U.S. was in 1949, while the last naturally occurring case in the world was in Somalia in 1977 (CDC 2002a). Smallpox is a serious, highly contagious, and sometimes fatal disease. The most common forms are Variola major and minor. Major is characterized by an extensive rash and high fever with an overall fatality rate of 30%; other forms are usually completely fatal (CDC 2002a). Transmission of the disease is usually through prolonged, face-to-face contact or through contact with bodily fluids or contaminated objects (i.e., bedding and clothing). According to the CDC (2002a), the incubation period for smallpox is seven to 17 days, in which the host is not contagious. The first symptom is usually a high fever (101 to 104 degrees Fahrenheit) and at the first evidence of the symptoms, the victim may be contagious. Other early symptoms include malaise, head and body aches, and vomiting, which last from two to four days. After that, a rash emerges in the mouth and the small red spots break open and spread huge amounts of the virus into the mouth and throat. The person is most contagious in this state. Later, a skin rash develops, starting at the face and usually encompassing the body within 24 hours. The rash becomes raised bumps that fill with thick opaque fluid, and they develop a bellybutton-like depression in the center. The bumps become pustules, which later form a crust and scab over. The scabs eventually fall off, after about three weeks since the initial rash, leaving pitted scars. The victim is no longer contagious once all of the scabs have fallen off. Smallpox (in addition to anthrax, tetanus, and tuberculosis) is known to have long-term persistence. A study conducted over a 13-year period starting in 1955 on smallpox victim scabs showed that virus particles were recoverable at least 13 years after death (DeNoon 2001).
(slide 16) Yellow fever, also known as the black vomit, is an acute virus transmitted to humans by the bite of the female mosquito (Crist 2000:96). The disease is characterized by fever, chills, headache, back pain, myalgia, nausea, and prostration (Singh 2001). Following this, the disease goes into remission for a few days, with recurrence of the fever within three to nine days. The toxic phase develops as the fever returns, with symptoms such as high fever, headache, lower back pain, nausea, vomiting, abdominal pain, jaundice (hence the name), and albuminuria. Severe cases include hemorrhagic manifestations, such as the characteristic black vomit (hematemesis), epistaxis, bleeding of the gums, and petechial and purpuric hemorrhages. The affected individual becomes confused and apathetic and eventually falls into coma, then dies. The last epidemic of the disease in the United States occurred in New Orleans in 1905. Yellow fever was prevalent during the Spanish-American War of 1898, killing over 5000 soldiers (only 968 were killed in actual combat) (University of Virginia 2002). Modern mortality rates may reach as high as 10% of those afflicted; the rate was up to 85% during the Spanish-American War.
Chemical Hazards
Chemical hazards associated with historic cemetery excavations include fluids used in embalming and materials used in coffin construction and decoration. (slide 17) In the United States, the mid-19th century saw the rapid rise, spread, and acceptance of a need for the body to be preserved as a necessary preliminary to interment (Habenstein and Lamers 1955:311-312). Prior to the Civil War, embalming was used primarily for preservation of scientific specimens (National Museum of Civil War Medicine 2003), while the practice of human embalming really began to take hold during the Civil War in an attempt to prevent decomposition prior to return of bodies of dead soldiers to their families. Civil War surgeons, learning from Dr. Thomas Holmes, embalmed arterially, through a slit made in the femoral artery (Johnson et al. 1996). Price of embalming ranged from $25 to $100, depending on the rank of the soldier. Later in the war, the government agreed to pay for the service (Colman 1997:57). When deceased soldiers were not embalmed (primarily those of lower rank), devices such as ice coffins and cooling boards were employed to delay decomposition during transportation (slide 18). Items such as these were in use since at least 1843, when John Good of Philadelphia received a patent for a “corpse preserver” and 1846, when Robert Frederick and C. A. Trump received a patent for a “Refrigerator for Corpses (Habenstein and Lamers 1955:316). Frederick and Trump’s cooler was highly successful, as it was economical and portable and allowed for storage of a fully dressed corpse that was “coffin-ready”. Use of corpse coolers persisted until around the turn of the 20th century, generally being replaced by the widespread acceptance of arterial embalming. Use of metal coffins and embalming were almost exclusive to wealthy folks during the mid-19th century, but advances in embalming practices made the procedure more accessible to the less affluent by the end of the century (Konofes and McKee 1996:16).
Early embalming fluids included alcohol, zinc and mercuric chloride, creosote, arsenic, sulfuric acid, and turpentine (Johnson et al. 1996). Some of these substances pose little threat to individuals excavating or analyzing materials from historic cemeteries, but others have the potential to be quite hazardous. Many never degrade into harmless by-products and remain with the coffin and skeletal material or seep into the surrounding soils. Historic embalming practices are an issue for archaeologists excavating and analyzing remains from historic cemeteries.
(slide 19) Arsenic is the most infamous early embalming agent. Use of this substance in embalming began around 1850, but really became popular during the Civil War. Dr. Thomas Holmes, touted as the “father of American embalming”, practiced and taught his craft steadily throughout the war. Arsenic was an ideal embalming fluid because it effectively killed the microorganisms responsible for decomposition (Konofes and McGee 1996:15), allowing for preservation of the bodies of dead soldiers to be returned home for burial. According to Konofes and McGee (1996:15), six patents for embalming fluid were issued between 1856 and 1873, requiring between 4 ounces and 12 pounds of arsenic per body. By the 1890s, arsenic was the primary embalming agent, although mercury and other fluids were also used (Meyers et al. 1998). Arsenic was banned in the United States by around 1910 because many embalmers were dying as a result of overexposure to the toxic substance (Meyers et al. 1998). Michigan was the first state to eliminate use of highly toxic chemicals in 1901 (Johnson et al. 1996:455). Of interest, use of poisonous embalming compounds, including arsenic and other metallic salts, was outlawed in France in 1846 (Habenstein and Lamers 1955:323). Bichloride of mercury was also prohibited in France in 1848 (Johnson et al. 1996:437).
Arsenic is toxic and persistent, and the elemental form never degrades into harmless by-products. The arsenic that endures today in cemeteries can potentially harm archaeologists or others working in cemeteries, or individuals drinking contaminated ground water. Borstel and Niquette (2000) note that during excavation, arsenic may appear as vivid blue or blue-green crystal formations, much like the crystals resulting from the disintegration of copper alloy items. Arsenic minerals emit a garlic-like odor when broken (Pough 1960). Borstel and Niquette (2000) suggest “extreme caution should be used if unusual odors, soil colors, lusters, or staining, or unfamiliar materials (particularly in finely divided or crystalline form) are noted.” Possible arsenic has been noted in at least a few graves excavated archaeologically in the United States. One interment dating to the early 20th century in the Upper Prater Cemetery (15Pi191) in Pike County, Kentucky contained several small concentrations of bright blue crystals that were assumed to have been arsenic (the material was not analyzed because all materials were reinterred the day they were excavated) (Bybee 2003). Nawrocki et al. (1996:11) noted for a metal coffin interment from the 19th century Rhoads Cemetery (12Ma777) in Marion County, Indiana “…a blue crystalline precipitant formed on the remains as they were drying…” The technical report for the cemetery excavation does not identify the material, but the description was suggestive of arsenic.
According to the National Park Service (NPS) (2000), arsenic can enter the body through skin absorption, inhalation, or ingestion, and affects the stomach, liver, intestines, heart, lungs, blood vessels, kidneys, nervous system, skin, and nails. Short-term arsenic poisoning is marked by weakness, headache, gastro-intestinal discomfort, changes in skin and nail texture and pigmentation, respiratory problems, coughing, irregular heart beat, breathing difficulty, and chest pain; chronic (long-term) effects include abnormal pigmentation of skin and nails, nonmalignant respiratory diseases, nervous system diseases, emphysema, kidney disease, heart disease, and various forms of cancer (NPS 2000). The Occupational Safety and Health Administration (OSHA), under 29 CFR 1929.1018, specifically regulates worker exposure to inorganic arsenic compounds.
(slide 20) Popular use of formaldehyde as an embalming agent began once use of arsenic was banned (Johnson et al. 1996). Formalin, a 37% solution of formaldehyde in water, became the new embalming standard in the early 1900s (Welton 2003). Formalin is carcinogenic and anatomists and embalmers who come in contact with this material have significantly higher risks for leukemia and brain cancer. Formaldehyde is also suspected in causing nasal and lung cancers. Formaldehyde, along with mercury, is most likely present in cemeteries dating to the 20th century. Roughly 350,000 gallons of formaldehyde is buried by the funeral industry each year in the United States (Welton 2003), but this fluid quickly evaporates out of embalming fluid and poses little threat to workers excavating historic cemeteries. Formaldehyde is completely soluble in water and evaporates quickly from soil. Its half-life in air is one to two hours, but could potentially take up to 12 hours to degrade. Formaldehyde causes major irritation of the mucous membranes, conjunctiva, skin, and upper respiratory tract. Skin contact causes necroses with hardening, tanning, and anaesthetization. Swallowing or inhaling large quantities of this substance causes esophageal or tracheal burning, gastrointestinal pain, nausea, unconsciousness, and collapse (Spectrum Laboratories 2001). OSHA regulates worker exposure to formaldehyde under 29 CFR 1910.1048.
(slide 21) Although not as widespread as either arsenic or formaldehyde, mercury was also used as an embalming agent, particularly during the 20th century, after arsenic was banned (Johnson et al. 1996). Mercury is usually discussed only as an aside in published literature concerning embalming fluids and historic cemeteries, and little information regarding its historic use as an embalming agent was found. Indeed, Borstel and Niquette (2000), Konefes and McGee (1996), and Meyers et al. (1998) offer only rudimentary mention of this element in their discussions of cemeteries and health safety, focusing exclusively on arsenic instead. Mercury was used in various medicines historically, including diuretics, antibacterial agents, antiseptics, and laxatives. In the late 18th century, antisyphilitic medications contained mercury, and it was during the 19th century that the phrase "mad as a hatter" was coined because of the chronic mercury exposure felters endured because mercury was used in hat making. It has recently been suggested that Abraham Lincoln’s erratic behavior prior to his inauguration as president in 1861 was brought on by his use of “blue mass pills”, whose main component was mercury. These pills were prescribed for apoplexy, worms, childbearing, tuberculosis, toothaches, and constipation (Mayell 2001). Lincoln reportedly stopped taking the pills in 1861 because they made him “cross”, after which, his erratic behavior ceased.
Mercury is the only metal that is liquid at room temperature. According to the Kansas Department of Health and Environment (2003), mercury is highly toxic and poisoning can result from vapor inhalation, ingestion, or skin absorption. Severe health problems resulting from both chronic and acute exposure to mercury include cough, chest pain, bronchial pneumonia, excitability, manic behavior, tremor, anorexia, gastrointestinal dysfunction, insomnia, weakness, memory loss, hearing and speech disorders, increased salivation, gingivitis, dermatitis (skin exposure to mercury), and airway inflammation (mercury vapor poisoning) (Pangborn 1994; Reno et al. 2000). Chronic toxicity is usually manifest as tremor, erethism, and stomatitis (Buckell, et al. 1993). Historically, calomel, or mercurious chloride, was used to clear the intestines and stimulate the liver, but the side effects were ulcerated gums, loosened teeth, and destroyed jawbones (Whorton 2002). An outbreak of mercurialism from the use of calomel in the mid-1900s was described as “pink disease”, which was exhibited by reddening of the palms and soles, irritability, insomnia, loss of appetite, skin rash, photophobia, and night sweats (Bates 1998). Mercury poisoning is usually misdiagnosed because of nonspecific signs and symptoms and lack of knowledge within the medical profession. OSHA regulates worker exposure to mercury under 29 CFR 1910.1048.
(slide 22) According to the Agency for Toxic Substances and Disease Registry (ATSDR) (2003), creosote is the generic name for a variety of chemical mixtures commonly known as wood creosote, coal-tar creosote, and coal tar, among others. Creosote mixtures have a smoky odor and vary in color from yellowish to black to dark brown. Creosote is composed of many substances created through burning beech and other woods, coal, or from the resin of the creosote bush (ATSDR 2003). Coal-tar creosote is the most widely used wood preservative in the United States, and was also used in early embalming. This lesser-known embalming agent was sometimes used as an anti-putrefactive, but had an objectionable odor. Creosote has also been used historically as a disinfectant, laxative, cough suppressant, and as a treatment for skin disease. ATSDR (2003) states that components of creosote that do not dissolve in water remain in place in a tar-like mass.
During a search of published literature, no reference to a cemetery excavation in which creosote was identified in the graves was found. Aside from its occasional use as an embalming fluid, it is also possible that creosote was used to treat coffin wood, as it has long been used as a wood preservative. Eating or drinking substances with high levels of creosote may cause a burning sensation and stomach pain. In addition, herbal remedies composed of creosote may cause liver or kidney damage. ATSDR (2003) suggests that brief direct contact with large amounts of coal tar creosote may result in a rash or skin irritation, chemical burns of the eye surface, convulsions, mental confusion, kidney or liver problems, unconsciousness, or death. Longer direct skin contact with low levels of creosote mixtures or vapors may result in increased light sensitivity, corneal damage, and skin damage. Vapor exposure can cause irritation to the respiratory tract. It is suspected that creosote is carcinogenic to humans, and major, long-term exposure (such as wood treatment or manufacture of coal tar creosote treated products) may be related to skin and scrotum cancers. OSHA has not established a substance-specific standard for occupational exposure to coal-tar pitch volatiles (creosote), thus exposures are regulated under the Air Contaminants Standard (29 CFR 1926.55, 1926.1102, and 1926.1129).
A much-overlooked aspect of historic cemetery excavations is the potential presence of lead in graves. Lead is a heavy and easily worked metal that, despite its known toxicity, has been used for thousands of years. Some historians speculate that the downfall of the Roman Empire was fueled by an epidemic of lead poisoning, possibly due to the liberal use of lead in their aqueduct system, cookware, and as a sweetening agent for wine (Donnay 1996). The EPA suggests lead poisoning was the likely cause of a pattern of mental incompetence in the Roman elite. The mental illness and ultimate deaths of various historical figures have been attributed to possible lead poisoning, including Ludwig von Beethoven and Vincent Van Gogh.
(slide 23) The ill-fated Franklin Expedition in search of the Northwest Passage in the 1840s could also blame lead for its downfall (Stock n.d.). Sir John Franklin’s two ships (Erebus and Terror) and 128 crewmembers were liberally provisioned with three years worth of canned food. The crew was apparently poisoned from the lead in solder, which was used widely to seal food storage tins. The tins were improperly manufactured, allowing lead to leach into the foods. The fact that officers, who had preferred access to tinned foods, died earlier than the rest of the crew, and the highly elevated lead levels in the hair of three preserved bodies exhumed in the 1980s (Beattie and Geiger 1993), all corroborated the assumption that lead poisoning contributed to the demise of the crew. The anorexia, weakness, fatigue, and paranoia brought on by lead poisoning must have made normal daily tasks required of the crew exhausting.
(slide 24) In the United States, lead has long been used in the production of utensils, in ceramic glazes, and as lining for storage containers, all leading to the inadvertent ingestion of this toxic metal. The usefulness of lead include its softness, high density, low melting point, ability to block radiation, resistance to corrosion, and readiness to form alloys and chemical compounds (Environment Canada 2002). Lead poisoning is probably one of the oldest occupational diseases, and the risks associated with use of lead have historically been considered a fact of daily life for various professions. Once lead is released through smelting, it never degrades. Archaeologically, this metal can potentially be found in a variety of artifacts, including lead shot and ceramic sherds that had lead in the glaze. Of particular interest to historic cemetery excavations is the use of lead for decorative coffin hardware, paint, and, possibly, decorative hair combs. Use of lead in paint dates back to at least 1884 (Askari and McDiarmid 2003), and didn’t let up until the 1940s, when less expensive additives were produced. Tortoiseshell and horn hair combs were often finished with lead salts, which provided iridescence to the combs. Decorative coffin hardware was often composed of white metal, which is described as any of several lead or tin based metals (Hacker-Norton and Trinkley 1984:11).
There is no “normal” level of lead for the human body because there is no biological value to this metal. Exposure to lead can be from air, dust, food, and drinking water. Acute exposure to this metal usually first presents with gastrointestinal symptoms (cramping, abdominal pain, and constipation), nausea, vomiting, and black tarry stools (California Division of Occupational Safety and Health [Cal/OSHA] 1997). Effects on the nervous system cause headache, confusion, stupor, coma, and seizures. Chronic lead poisoning symptoms include fatigue, apathy, and gastrointestinal distress. Further chronic exposure results in central nervous system issues, such as insomnia, confusion, difficulties in concentration, memory problems, and motor neuropathy (Cal/OSHA 1997). OSHA regulates worker exposure to lead under 29 CFR 1926.62.
Physical Hazards
Physical hazards of working in cemeteries include any that are normally associated with an archaeological excavation. Archaeological work is subsumed under the OSHA regulations for construction (29 CFR 1926) and, although nothing specifically regarding archaeological excavations is noted, several standards are applicable. Perhaps most significant are 29 CFR 1926.651 (specific excavation requirements) and 1926.652 (requirements for protective systems). 29 CFR 1926.651(c)(2) requires that a safe means of egress (i.e., ladder, stairway, ramp) be located in a trench that is 1.22 m (4 feet) or more in depth so as to require no more than 7.62 m (25 feet) of lateral travel. Although grave shafts are usually no more than around 2 m in length, depths can range well below 1.22 m, thus use of a ladder or other means of egress would be required for each deep grave. 29 CFR 1926.651(j)(1) requires protection of workers from loose rock or soil that could pose a hazard by falling or rolling from an excavation face, and OSHA requires that scaling to remove loose material or other equivalent protection be conducted. Similarly, 29 CFR 1926.651(j)(2) requires protection of workers from materials or equipment that could fall or roll into excavations. This standard requires that materials and equipment be located at least 61 cm from the edge of excavations. In essence, 29 CFR 1926.651(j)(1) and (2) require that grave markers, grave shaft fill, or other loose materials be removed from the top edges of deep grave shafts, and that any other items be placed well away from the grave shaft openings to avoid the chance that materials may roll or fall into the pit.
29 CFR 1926.652(a) relates to protection of employees in excavations, with 1926.652(a)(1) requiring that workers be protected from cave-ins by an adequate protective system. Exceptions to the use of a protective system include excavations that are made in stable rock, as per 29 CFR 1926.652(a)(1)(i), or excavations that are less than 1.52 m (5 feet) in depth and examination of the ground by a competent person provides no indication of a potential cave-in, as per 29 CFR 1926.652(a)(1)(ii). If neither of these two exceptions can be met, protective systems that have the capacity to resist without failure all loads that are intended or could reasonably be expected to be applied or transmitted to the system must be used. Protective systems could include benching, sloping, or shoring. Thus, graves that are less than 1.52 m deep and have no potential for cave-in or graves that are excavated in solid bedrock do not require use of a protective system. If it is expected that graves will be greater than 1.52 m deep, mechanical removal of grave shafts and surrounding soils to a depth that would not require use of protective shoring (or an alternate means of egress) could be implemented. 29 CFR 1926.652(f) states that workers are not to work on the faces of sloped or benched excavations at levels above other employees except when employees at the lower levels are adequately protected from the hazard of falling, rolling, or sliding material or equipment. Thus, when one person is working in a deep grave shaft, other workers should not be located along the adjacent ground surface, unless the person within the grave shaft is wearing a hard hat. In addition, 29 CFR 1926.100(a) requires that protective helmets be worn when working in areas where there is a possible danger of head injury from impact, or from falling or flying objects, or from electrical shock and burns.
The U.S. Department of Labor takes OSHA compliance very seriously, and any authorized representative has right of entry to any site of contract that is subject to section 107 of the Contract Work Hours and Safety Standards Act. The representative may inspect or investigate the matter of compliance with safety and health standards. Indeed, Cultural Resource Analysts, Inc. was charged a hefty fine of over $11,000 for violations of various standards in 1995 (the fine was later reduced to $500 and a stern warning of no further leniency was given) (Niquette 1997). Violations recorded by an OSHA inspector included lack of appropriate egress, location of materials or equipment less than 61 cm from the edge of excavations, and lack of protective helmets. The incident resulted in what Niquette referred to as a “corporate lifestyle change” (1997) in which OSHA regulations were strictly adhered to; the company continues today to abide by all OSHA regulations in both the field and office. The reader is urged to inspect the U.S. Department of Labor, OSHA regulations (Standards – 29 CFR) prior to conducting archaeological investigations of historic cemeteries. The regulations can be accessed through the following webpage:
http://www.osha.gov/pls/oshaweb/owasrch.search_form.
Aside from abiding by OSHA regulations, other actions should be taken to minimize the risk of injury to workers. For example, while working in a shaft that has grave markers or marker anchors at either end, the markers should be removed prior to excavation. Loosening the surrounding soil could free the markers or anchors, causing them to topple into the grave on top of a worker. In addition, if the topsoil is stripped or the grave shafts are excavated mechanically, make sure the root systems of nearby large trees have not been cut. If they have, request that the backhoe operator knock the trees over (if possible).
Prior to excavation of any cemetery, soil testing must be conducted to determine if arsenic, mercury, or lead are present. As mentioned previously, arsenic is probably the most significant chemical health risk to workers in historic cemeteries. The element occurs naturally in rocks, soils, water, plants, and animals. Distribution of arsenic concentrations in groundwater reflects bedrock lithology, and regions underlain by sandstone, shale, coal, or poorly consolidated sands and mudstones have the highest concentrations of groundwater arsenic (Fisher 2002). The average soil in the United States has 5 parts per million (ppm) of arsenic (Lindsay 1979, cited in Meyers et al. 1998). Soil samples taken from a cemetery in Montgomery County, Kentucky (15Mm137) suggested the presence of arsenic in at least one interment (soil samples were analyzed for three of 17 graves). The interment in question had an arsenic level of 80 ppm, while the two other graves had levels of 6.07 and 30 ppm (the control sample had 37 ppm) (Bybee and Richmond 2003:58). The ridge on which the cemetery was located was underlain by shale bedrock, thus the lower levels of arsenic found in two interments and the control sample may have been representative of the natural levels of this element in the local soils. Meyers et al. (1998) suggest guidelines for the interpretation of arsenic levels from historic cemeteries. They state that with levels less than 20 ppm, arsenic contamination is likely absent, while levels ranging from 20 to 100 ppm suggest contamination may be present and appropriate protective measures should be executed. Levels greater than 100 ppm are highly suggestive of arsenic contamination and an expert assessment of the sediments should be undertaken. The elevated levels of arsenic identified at the 15Mm137 cemetery were suggestive of the use of the element as an embalming fluid, but were not conclusive. Of note, however, was the presence of three interments in which human hair, and in one instance, feathers from a pillow, were recovered. According to the NPS (2000), arsenic tends to adhere strongly to hair and feathers. The presence of hair and feathers, and the veritable absence of human skeletal remains in these interments, may be associated with the level of arsenic in the graves, which may or may not have been influenced by 19th century embalming practices.
(slide 25) The types of protective gear to be used for an excavation will be determined by the potential hazards present. Most importantly, exposure of the lungs and hands to potentially hazardous biological or chemical materials should be minimized (Flanagan 1995; Galloway and Snodgrass 1998). If hazardous materials are believed to be present, use of dust masks, gloves (rubber, nitrile, or vinyl), Tyvek overalls, and long sleeved shirts and pants may be appropriate. Latex gloves should be worn whenever human remains or coffin hardware are handled, as they provide more maneuverability than bulky work gloves. It is also recommended that clothes be changed daily and that the bottom of the grave shaft be lined with plastic while working within the coffin. Disposable Tyvek booties can also be worn to keep work boots free of adhering soils or sediments that may contain hazardous materials. In addition, water should be sprayed on dry soils to inhibit dust particles from becoming airborne and screens should be placed downwind from workers (Flanagan 1995). As for hygiene, eating, drinking, and smoking should be confined to a designated area, and clean water and soap should be made available for washing.
Although the biological, chemical, and physical hazards presented here may not be the only potential hazards at a cemetery, they likely comprise the majority. For bacterial, viral, or rickettsial diseases, there is little chance that infection to the archaeologist performing an excavation or analysis will occur if all remains are skeletonized. This changes, however, with the presence of soft tissues. When an individual has been interred in a metal coffin, particularly one in which the seal has not broken, or the individual has been embalmed, there is a good chance soft tissue will be present. This tissue should be treated as a potentially hazardous material. Testing for arsenic, mercury, and lead should be conducted prior to excavation, and appropriate protective gear should always be worn.
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