Ecological Impacts
of Cemeteries
Cemeteries may serve as a reservoir for several toxins and pollutants which can lead to the contamination of soil and groundwater while they can be a thriving ground for pathogens some of which may be resistant to antimicrobials.
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Traditional burial practices may lead to the spread of bacteria, fungi, viruses, and several organic or metallic ions. Likewise, cremation can produce particulate matter, volatile organic toxins and trace gases like oxides of sulphur, nitrogen and carbon monoxides. Both of these methods introduce soil contaminants that may interact with water to form necroleachate, an effluent rich in organic and inorganic matter released from the decomposing bodies. These may remain in soil, seep into the water table or arise with flooding water and contaminate surface water or river runoffs.
The process of embalming mainly involves the application of formaldehyde. The embalming fluids are meant to slow down the decomposition of the corpse so that the body can be viewed for long enough. Formaldehyde is a well known carcinogen and has been classified as a hazardous and polluting substance. Each time an embalmed body is buried, about three gallons of embalming fluid pumped into the body gets buried with it. This not only poses health risk to the mortuary workers exposed to the corpse but also harms the microorganisms involved in the decomposition of the body and inhibits its breakdown for a sustained period that may allow contamination of soil and thus groundwater. The formaldehyde may itself trickle down into the soil and reach the waters below.
Many cemetery practices also involve encasing the body into coffins. The wooden ones generally contain sealers, varnishes, and preservatives ingredients like copper naphthalene and copper arsenate harmful to the environment. They have paints with colouring agents based on toxic metals like lead, mercury, cadmium and chromium. Additionally, they are decorated with handles or other ornaments to enhance the aesthetic value. These mostly contain minerals like zinc, copper silver and gold spray painted, electroplated or simply attached to them. Burial of such coffins can serve as a long term environmental hazard as they degrade over time releasing harmful toxins that accumulate or spread in the soil and seep into the groundwater table.
Metals like lead are known to damage neuromuscular, cardiovascular and kidney while they may spontaneous abortions, fetal and child mortality and developmental disorders. Chromium may lead to the formation of ulcers, allergic reactions and immune system disorders. Mercury, a known neurotoxin can lead to neurodegenerative disorders and affect cognitive development in children while it has been known to increase several types of tumors in rats tested in the lab. This can trigger conditions like neurodegenerative diseases, allergic reactions, hormonal imbalances and damage to vital organs like the kidney, liver and heart. Such metals can also act as carcinogens and reduce fertility in both men and women.
Many humans also have metal-based substances implanted into the body intended to protect certain organs or replace the ones that have lost their function to prolong the life of individuals. But even after death, these substances remain in the body and slowly degrade with it releasing toxins. Dental filling based on mercury is a common example of such a substance. Apart from that there are several artificial scaffolds, prosthetics, implantable devices and life support equipment like artificial pacemakers, esophageal tubes and other medical products based on materials that don’t occur naturally and can serve as a source of pollutants.
Some individuals may also be administered with radioactive compounds for diagnosis or treatment during their lifetime which can accumulate in the body. These radiopharmaceuticals can be released into the soil on burial as remains of cremation. These pose as radiation hazards for exposed workers or to the community. In 2021, the news of the death of 20 vultures in Assam made headlines after feeding on carcasses of eagles containing high levels of antibiotics.
Decomposing bodies serve as a source of nutrients for soil microorganisms or may add up to many soil microorganisms. Cemeteries can also be a breeding ground for several antibiotic resistant microorganisms. Corpses may introduce such pathogens to the soil or foster already existing microbes in graveyard soils polluted by sewage water or other contaminants. Corpses may nurture microorganisms resistant to antibiotics or contribute to the development of acquired antibiotic resistance by facilitating contact of various microorganisms with the resistant strains. Another mechanism involves the development of resistance by introducing antibiotics that remain in the body allowing selective evolutionary pressure and thus the development and proliferation of more robust strains.