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Hidden hazards in health care.

Developed by:

Patricia B. Reinhart, RN

Staff Nurse, Ohio State University Hospital and

Nurse Entrepreneur

Thornville, Ohio

Presented by:

Ohio Nurses Foundation

4000 E. Main Street

Columbus, Ohio 43213-2983

614-237-5414

www.ohnurses.org

Copyright [c] 2001, 2003, 2005, 2007 by Ohio Nurses Foundation

Nurses, physicians, and other health care workers strive to defend themselves, their families and their communities against illness. Yet unknown to many of us, the purchasing and waste disposal practices of health care institutions often undermine their own purpose by contributing to the disease process. While most nurses are concerned about the possible risk of AIDS, hepatitis, and back injuries, there are insidious hazards in health care settings that affect us all.

Health care institutions, driven by mandates from federal, state and local governments, are assiduously attempting to contain and prevent the spread of diseases. The process has led to a burgeoning volume of health care waste and pollutants.

RED BAGS

Eighty-five percent of hospital waste is like household waste, it can be recycled or re-used. Only 15% is regulated (infectious) waste, which is generated while diagnosing or treating a patient. Regulated waste includes IV bags, gauze dressings, syringes, and bed pans. The portion of waste that can transmit an infectious disease is to be disposed of in "red bags" so that it may be more easily identified. Most regulated waste does not need to be incinerated. Only pathological waste (tissues and organs) must be incinerated. It has been reported that pathological waste comprises only 2% of total hospital waste. Some hospitals incinerate 75-100% of their waste even though infectious waste costs 5 times more to dispose of than regular trash (Rutala and Mayhall 1992).

The coloring agent used in "red bags" and rigid needle boxes is cadmium, a known carcinogen. Cadmium is a heavy metal that can cause profound neurological effects similar to other heavy metals like lead and mercury. The Agency for Toxic Substances and Disease Registry (ATSDR) estimated that in the U.S., about 2 million pounds of cadmium are emitted during cadmium production and another 2 million pounds from cadmium use per year. Burning of fossil fuels (coal and oil) and incineration of waste contribute to the cadmium emitted to our air.

Increases in cadmium soil levels have resulted from application of municipal sludge and phosphate fertilizers. This has caused increased human exposure from food chain accumulation of cadmium in plants and animals. Cadmium contaminated topsoil may be indirectly responsible for the greatest human exposure to cadmium due to its uptake in edible food and tobacco. Inhalation of cadmium has been strongly linked to lung cancer. Workers in smelters and medical waste incinerators which burn plastic are at greater risk for cancer. The greatest potential for above average exposure to cadmium to the general public is from smoking which may double an individual's intake of cadmium. Food is the main source of human exposure for non-smokers. Some cereal grains, such as sunflower kernels, have been found to have a high concentration because of their genetic and physiological characteristics. Fish caught in contaminated water also pose a risk. The EPA has recommended monitoring of cadmium in fish and shellfish tissue samples.

The World Health Organization has set the provisional tolerable weekly intake (PTWI) of dietary cadmium at 7 micrograms per kilogram of body weight. Exposure from water is generally 2 micrograms per day. Different cadmium compounds have varying uses. Cadmium carbonate and cadmium chloride have been used as fungicides for home lawn and golf course turfs. By 1997, all cadmium pesticides had undergone voluntary cancellation. Cadmium oxide is issued as an additive in plastics such as Teflon. Cadmium sulfide is the most widely used cadmium compound and is primarily used as a pigment. Europeans banned the use of cadmium pigments in cosmetics in 1990. It is also used as a stabilizer in PVC.

Cadmium is listed as a known carcinogen by The World Health Organization's (WHO) International Agency for Research on Cancer (IARC). The FDA, EPA, OSHA (Occupational Safety and Health Administration), and NIOSH (National Institute for Occupational Safety and Health) have made recommendations and regulate levels of exposure to cadmium.

In the past, hospitals commonly placed red bags in all the patient care areas and placed any waste that came into contact with a patient into them. This practice not only wasted a great deal of money but was also responsible for the generation of large amounts of toxic pollution when the red bagged waste was treated. "Honor hospitals" like New York's Beth Israel Medical Center have begun to segregate infectious waste. It has discovered that the best way to keep non-infectious waste out of these red bags was to educate employees as to what the definition of "infectious" waste really is. Then they strategically placed "red bag" garbage cans to discourage employees and visitors from putting regular trash in the infectious waste stream. The employee education program included stickers on trash bins, signs, and one-on-one meetings with employees who didn't understand the program. This, along with a rigorous monitoring system and strategic placement of waste bins, dramatically reduced the amount of red bag waste at Beth Israel for a cost savings of 60%. In 1997 the estimated savings was $900,000 on all waste and over $600,000 on medical waste. Waste segregation programs like Beth Israel's prove that hospitals can stay in line with current regulations while reducing waste management costs.

DISPOSABLES

The 1994 Dioxin Reassessment done by the United States Environmental Protection Agency (USEPA) brought to light that the incineration of medical waste was the single largest source of dioxin air pollution.

American hospitals generate 2 million tons (4 billion-4,000,000,000 pounds) of waste a year. If that amount were piled on a football field, it would reach a height of nearly a mile. In the 1930s, hospitals generated 7 pounds of waste per day per patient. In the 1960s, that grew to 8 pounds per day. The 1970s and 80s saw a switch from reusable products to disposables since hospitals believed it to be less expensive and more convenient to use. Now, 40 years later, that figure has doubled to 16 pounds per patient per day. High disposal costs and regulations regarding treatment and disposal of toxic substances have made waste management one of the top issues facing hospital administrators.

The most environmentally responsible hospitals have responded to this problem by developing plans for waste reduction and recycling. They have discovered that waste disposal costs overshadow the supposed benefits of disposables. Less inspired facilities continue business as usual relying on expensive medical waste incinerators to dispose of regulated and non-regulated waste.

POLY VINYL CHLORIDES

Polyvinyl chloride (PVC) plastic usage has increased because of its flexibility, strength, suitability for steam sterilization, resistance to kinking, transparency, and cost. PVC represents 25% of all plastics used in medical devices. Its rise to dominance, especially in the bag market, is part of a bigger trend in the displacement of glass, aluminum and metals. The demand for medical bags and tubing containing polyvinyl chloride plastic in the U.S. alone totaled 270 million pounds by 1994.

Because of disposables, plastic now constitutes 15-20% of the hospital waste stream. The environmental impact of this high plastic usage is serious. From the production to the disposal of PVC, toxic compounds are produced and released into the environment. PVC is a product that is 57% chlorine by weight. When it is incinerated, the chlorine is released and combines with organic matter to produce dioxin. The dangers of dioxin are described below.

DIOXIN

Dioxin is the common name for a class of 75 chemicals; it has no commercial use. It is a toxic waste by-product formed when products containing chlorine are manufactured or when waste that contains chlorine is burned. PVC plastic is a major source of the chlorine in medical waste. Dioxin is one of the most toxic classes of chemicals known. Dioxin is of particular concern because of the threat it poses to the environment and human health. Dioxin is a known carcinogen. Liver, lung, stomach, and connective tissue cancers, as well as non-Hodgkin's lymphoma, have all been associated with dioxin. It has been linked to birth defects, decreased fertility, immune system suppression and other hormonal dysfunctions. Because of the threat dioxin poses to human health, some medical associations have passed resolutions calling for the elimination of PVC.

Dioxin is atmospherically transported and enters the food chain long distances from its point of origin. Dietary sources, which account for 90% of human exposure, include meat, dairy products, eggs, and fish. It bio-accumulates, building up in fatty tissues and concentrating in organisms as it moves up the food chain. According to the USEPA, adults eating an average diet are consuming 300500 times the daily safe dose of dioxin. Because of the high fat content of breast milk, nursing infants are exposed to about 50 times the average adult dose and may receive more than 10% of their lifetime exposure during the nursing period, a time when they are extremely vulnerable to dioxin's toxic effects.

DI-ETHYLHEXYL PHTHALATE

PVC is a relatively rigid and brittle polymer, but it is unique in its ability to accept large quantities of additives to achieve the specific qualities that make it so desirable for use in medical products. Flexibility is achieved through the addition of chemical plasticizers. The most widely used group is the phthalate esters. Di-ethylhexyl phthalate (DEHP) is the most important phthalate in the production of medical devices and is the international standard PVC plasticizer.

DEHP has a high compatibility with PVC resins. The amount of the plasticizer used depends on the flexibility needed. A recent study found that some medical devices contain between 29% and 81% DEHP by weight (DiGangi, 1999). DEHP is not chemically bound to the polymer, but is dispersed in the matrix. Because of this it can leach out during normal use. It may leach out directly, or the extracting material such as IV fluids or blood products may diffuse into the PVC matrix dissolving the plasticizer and the two leach out together. The most important factors in DEHP leaching are temperature, concentration of the phthalate, agitation, storage time, and surrounding media. Researchers Latini and Avery (1999) found that 6-12% DEHP was lost from endotrachial tubes used to provide Continuous Positive Airway Pressure (CPAP) to premature infants. They found that plasticizer loss over time increased and that the color and flexibility changed consistent with its loss. DEHP exposure by individuals, who are ill, and therefore potentially less able to cope with any toxicant, is of particular concern. According to Huber, et al. (1996) and other researchers, human exposure to DEHP through medical treatments can be substantial.

ENVIRONMENTAL EXPOSURES TO DEHP

The overall growth rate for consumption of DEHP has decreased since the late 1980s based on concerns that DEHP acts as an animal carcinogen (NTP,1982) and is labeled as a possible human carcinogen by the International Agency for Research on Cancer (IARC, 1987). This concern has caused some manufacturers, including some in the toy industry, to switch to other phthalates. Non-plasticizer uses of DEHP include insecticides for orchards and as an inert component in pesticide formulations. Major uses of DEHP for PVC include such products as flooring, wall coverings, furniture and footwear. While DEHP use is decreasing in many sectors, medical applications actually represent a growing market (SRI, 1996).

Key studies have documented the toxicity of DEHP on different organs: the testis, ovaries, heart, lungs, kidneys, liver, and the fetus and embryo. Of concern to researchers are reproductive and other developmental impacts on children. The National Center for Environmental Health (NCEH) and U.S. Centers for Disease Control have embarked on a multi-year survey of phthalate metabolites in the U.S. population (Brock, 1999).

DEHP has been considered a priority environmental pollutant by governments in North America and Europe (Wams, 1987) due to its ubiquity in the environment. Phthalates in general are considered to be among the most universal of all environmental pollutants. Phthalates have been found throughout the globe, from the air above the ocean, to the ocean floor, to the Andes Mountains in Bolivia. (Toppari, et al., 1996).

Ingestion of contaminated food is the primary route of DEHP exposure in humans. Sources of food contamination include: direct contamination (e.g. fish ingesting contaminated water); manufacturing the food product (e.g. use of PVC milk tubing); and leaching from food in PVC packaging. We can also be exposed through drinking water, water from wells near land fills, production facilities, or waste sites that could result in higher than average exposures.

Exposure via inhalation of ambient air is generally considered a minor source, except in certain indoor settings where there has been extensive use of PVC products, especially in construction materials. Wams (1987) and Oie,et al. (1997)found that small children are at risk of being more heavily exposed to DEHP through indoor air because they spend more of their time indoors and, per unit body weight, they have a respiration rate twice that of an adult.

DEHP enters the environment throughout its entire life cycle: production, use, and disposal. Its half life is 2-5 weeks in aerobic conditions, but in sediment its half life is estimated to be over 100 years due to anaerobic conditions (Baughman, 1980).

EXPOSURE THROUGH MEDICAL DEVICES

Warnings from scientific researchers on DEHP phthalate plasticizer leaching from medical products made of PVC began soon after the products came into common use. Unfortunately, these public health warnings have gone unheeded by the government, chemical and plastic manufacturers and much of the health care industry. PVC medical devices containing DEHP are used extensively in modern health care facilities in examination gloves, blood bags, tubing (endotracheal and transfusion) and catheters. Studies as early as 1960 noted that certain types of PVC tubing used in rat experiments would release additives affecting the heart.

Human exposure to DEHP in the general population is reported to range from 0.5 to 2.0 mg per day (Wams, 1987). The Swedish Chemical Inspectorate (KemI, 1997) cited sources that calculated that acute exposure through blood and plasma transfusions can result in up to 120 mg DEHP per liter of blood; treatment on a heart/ lung machine can result in exposure to DEHP of up to 14 mg/kg per day; and chronic exposure via dialysis can result in 370 mg per treatment. Infants on Extra Corporeal Membrane Oxygenation Therapy (ECMO) are exposed at a rate of 3.5mcg/ ml per hour after 48 hours and 4 mcg/ml after 84 hours. Premature and ill newborns receive among the highest doses of DEHP from medical devices since they are supported by ECMO, mechanical ventilation, IV therapy, blood transfusions, and tube feedings.

Certain drugs may cause leaching of DEHP from PVC IV bags into solutions. Detectable leaching into drugs such as Diotoxinor cyclosporine or the solvent Polysorbate 80 have been found to occur in as little as one hour and increased over the 24 hour test period. Taxol (used to treat AIDS-related Kaposi's sarcoma, ovarian, and breast cancer) is a drug known to cause leaching of DEHP into solution. The preparation instructions for IV administration recommend that the solution be prepared and stored in glass or polyolefin bottles and administered with non-PVC or polyethylene-lined administration sets. A similar warning exists for the cancer medication Taxotere (Docetaxel). Other drugs known to leach DEHP from PVC tubing are: Etoposide (VePesid), Teniposide (Vumon), Librium, Monistat, Sandimmune, Tacrolimus, Fat Emulsions and Vitamin A.

Investigators have noted that the quantity of plasticizer extracted is greater for solutions with a higher lipid (fat) content. Acutely and chronically ill patients receiving TPN and enteral feedings are at high risk of exposure to DEHP.

A 1994 article in the Journal of Intravenous Nursing found that hospital staff may not be aware of leaching of DEHP from IV products. They may not read package literature that directs the use of non-PVC products (Noah and Godin, 1994). This may result in certain lipid-based products, such as alimentary fat emulsions or parenteral nutrition, being administered inappropriately to chronically ill patients (including pregnant women) for extended periods of time. The authors concluded that although PVC plastic has a valuable role in the provision of medical care because of its low cost and flexibility, it is nevertheless evident that many infusates leach DEHP from PVC in sizable amounts with toxic results and caution is advised. Cost containment, versatility and convenience are important aspects of modern health care, but not at the expense of safe, risk-free therapy."

MERCURY

In addition to avoiding unnecessary incineration of waste, there are a number of other steps that hospitals can take to reduce their negative impact of mercury on the environment. Hospitals need to examine the materials they use and their toxic effects. Many of the toxic items used in hospitals are easily replaced with nontoxic alternatives. The easiest products to start with are mercury-containing instruments.

Mercury is present in batteries, thermometers, Miller-Abbott tubes, Cantor tubes, sphygmomanometers, electrical equipment, fluorescent lamps, laboratory reagents and disinfectants. Alternatives already exist for most of these. Where they do not--for example, in energy efficient fluorescent light bulbs-- recycling would prevent the release of mercury into the environment. (Refer to the University of Massachusetts at Lowell's Sustainable Hospitals Project for a list of mercury alternatives. The web address is www.uml.edu/centers/LCSP/hospitals).

When someone becomes ill, one of the first things they do is to reach for the thermometer to check their temperature. Most of us do not realize that the silvery-white liquid inside is a hazard to our health. Mercury affects the brain, spinal cord, and liver. It affects the ability to feel, taste, and move. It can cause tingling sensations in the fingers and toes, a numb sensation around the mouth, and tunnel vision.

Mercury crosses the placental barrier and affects fetal development by preventing the brain and nervous system from developing normally. Affected children show lowered intelligence, impaired hearing and poor coordination. Their verbal and motor skills may be delayed. Because of this, the federal government recommends that women who are pregnant or may become pregnant not eat mercury-contaminated fish. Currently there is so much mercury pollution that 39 states are warning residents not to eat fish caught in all or some of the states' lakes, rivers or streams.

According to the Ohio Department of Health, there is statewide mercury advisory for women of childbearing age and children age six and under. These groups are advised not to eat more than one fish meal per week from any Ohio water body, and not more than one fish meal per month for any body of water where mercury is a noted contaminant.

Mercury is volatile and evaporates at 70 degrees Fahrenheit. If a mercury thermometer breaks, it will evaporate, potentially reaching dangerous levels in indoor air. It precipitates out on cold surfaces just as steam from a hot shower does. There, it condenses and trickles to the floor where it lurks and repeats the cycle continuously. The immediate and greatest risk is in small rooms and to small children. Exposed children may require months of treatment before they are well. The long-term risk is that it will evaporate to the outdoors rising to the clouds and returning to the earth in the form of rain where it will contaminate the soil and water. Eventually it works its way up the food chain reaching fairly high concentrations in top predator fish like tuna, swordfish, and shark.

Levels of methyl mercury in tuna tested by the FDA in 1993 ranged from 0.01 to 0.75 PPM. If the current FDA advisory were transformed into an enforceable standard for mercury contamination in fish, it would not come anywhere near protecting the public health. A pregnant woman would exceed the EPA safe dose of mercury by eating just 1/26th of a can (6.5 grams) or (a little more than a teaspoon) of tuna if it were contaminated with mercury at the FDA limit of 1.0 PPM. A four-year-old would exceed the EPA safe dose by eating one can of tuna every 98 days. This is based on long term risk and does not consider damage during "windows of vulnerability".

An average home fever thermometer contains 1.59 grams of mercury. That is enough to potentially contaminate 9,000 cans of tuna at the FDA limit of 1.0 PPM.

Mercury is a persistent, bio-accumulative toxin. It has been linked to numerous negative health effects in wild life and humans. Its natural state under ambient temperatures is a silver-white liquid that changes easily from solid to liquid to gas, allowing it to circulate in the atmosphere and the environment. There are three major forms of mercury but the one of most concern is methylmercury. It is formed from inorganic mercury by bacteria and is the most harmful because, unlike other forms of mercury, it is absorbed by the muscle tissue and can build up in the food chain. It cannot be destroyed by incineration.

The earliest cases of mercury poisoning were diagnosed because of gross symptoms (death or severe neurological damage) resulting from occupational exposure. Many workers in the Roman Empire died as a result of exposures in the mercury mines of Almaden, Spain (Myers 1996).

High levels of occupational exposure were later identified as the cause of "mad hatters" disease, in which hat makers in the 19th century were exposed to high levels of mercury and suffered brain damage. Permanent neurological damage of this type (dementia) is now known to occur in adults at doses of about 0.73mg/kg/day (Davis 1974).

The first truly widespread case of recognized mercury poisoning occurred along Minamata Bay in Kyushu, Japan in the mid-1950s. Originally called "Minamata Disease" 750 people died and thousands suffered permanent neurological effects. The epidemic was traced to methylmercury contamination of fish by a local chemical plant. This episode marked a major shift in the study of mercury poisoning. It was here that scientists first noted that doses that were harmful to fetuses did not affect their mothers.

The largest known accidental poisoning to date occurred in Iraq in three separate waves between 1959 and 1972. The outbreak occurred as a result of people eating seeds-mostly wheat-that were coated with a methylmercury-based pesticide. It claimed 6530 victims in a public health disaster of epidemic proportions (Watanabe, 1996). Researchers determined a dose-response curve for in-utero exposure to mercury. It suggested that the safe level of mercury exposure that the WHO was using at the time would not protect children in the womb. In 1972 the safe level was thought to be 0.00047mg/kg/day. The USEPA used these data in 1985 to set a lower reference dose (RfD) at 0.0003mg/kg/day. This level was again lowered in 1995 to 0.0001 mg/kg/day. The safe levels continue to drop.

Many scientists question whether the current standard will protect the population from more subtle effects of mercury poisoning. The RfD for mercury is based on results from an acute exposure study. The long half-life of mercury elimination from the brain, coupled with the fact that most mercury exposure is long term, increases the uncertainty factor. Mercury may accelerate the neurodegeneration associated with aging.

According to the U.S. EPA's 1997 Mercury Report to Congress, 87% of all anthropogenic (man-made) mercury in the environment comes from incinerators, power plants and other combustion sources. Medical waste incineration accounts for 10%. That is an annual discharge into the air of 16 tons, enough to contaminate 14 million 20 acre-sized lakes (approximately 20 times the size of Lake Michigan) to the point where the fish are unsafe to eat.

CONCLUSIONS

SOLUTIONS TO THE DEHP THREAT

The FDA does limit the amount of plasticizer to 30% of materials in food containers. The U.S. toy industry has eliminated the use of DEHP in toys. The plasticizer is still found in some toys produced and sold in other countries (Stringer, et al., 1997).

Health care decision-makers should consider the environmental health impacts of the products they choose as part of their health care mission. Chlorine and DEHP-free alternatives exist. Easily replaced items include patient identification bracelets and cards, IV bags, compression stockings and fluid collection devices. These plastics do not produce dioxin when manufactured or burned. Rigid PVC products often have alternatives made of metal or non-chlorinated plastic such as polypropylene and polycarbonate. New non-chlorinated plastic polymers are being developed.

SOLUTIONS TO THE MERCURY THREAT

There are 11 million nurses worldwide. If each one would take a mercury thermometer to a hazardous waste recycling center, potentially 99 billion cans of tuna could be spared mercury contamination.

Acting together, nurses could hold mercury fever thermometer exchanges at their local hospitals, offering mercury free substitutes for those brought in. The news media would provide free advertising for such an event since it is a public health issue. It is good public relations for hospitals and nurses alike.

Pediatric nurses can educate parents about the hazards of a broken thermometer encouraging them to take them to a "household hazardous waste recycling day" or to a hazardous waste collection facility that does not incinerate the waste. Or they can set up a recycling center at their place of employment.

Post partum nurses can discourage their hospitals from sending mercury fever thermometers home with new parents.

Nurses need to know how to clean up a mercury spill and to teach others the technique. First turn down the heat or turn off the air conditioner to prevent the spread of the vapors. Open the windows and leave them open for at least two days. Don't vacuum it up and don't sweep it up with any kind of a brush. Wear gloves when cleaning up the spill. Gather up all the beads that are visible with an eyedropper, using a flashlight to visualize them. Use wet paper towels to gather the remaining beads. Put the mercury along with the cleaning materials in a labeled closed container. It can be taken to a recycling center. NEVER throw it or a mercury thermometer in the trash. NEVER pour mercury down the drain. In 1998, the American Hospital Association (AHA) signed an agreement with the USEPA committing to virtual elimination of mercury from hospital waste streams by the year 2005. Many are hoping to be mercury free by 2003. In order to accomplish this, many hospitals are phasing out the use of mercury thermometers and other mercury-containing equipment. Nurses can set an example in their homes and communities. Talk to your health care provider; ask your local pharmacist and drugstore to take mercury thermometers off the shelves. Help distribute brochures to childcare centers, PTAs, and other organizations concerned with children's health.

GENERAL SOLUTIONS

Form a coalition with your hospital administrators to establish a "green team" that would be authorized to identify wasteful practices and design a waste management strategy that incorporates waste reduction, reuse and recycling measures.

Take steps to initiate environmentally preferable purchasing practices. Assign a materials management staff to research and communicate with suppliers concerning the safe substitution of materials (sterilizing solutions, floor cleaners, cooling unit biocides) to reduce the toxic chemical exposure of staff and patients, and to reduce environmental pollution emissions and impacts. Prevention is still the best medicine.

Several organizations formed the Health Care without Harm (HCWH) campaign in 1996. Its coalition now exceeds 271 organizations in 25 countries. Just as the Hippocratic Oath promises to "first do no harm", the HCWH campaign is based on the premise that health care practitioners have a responsibility to work toward the elimination of environmental harm resulting from health care practices, and to work for an ecologically sustainable health care system. ONA and ANA are members of HCWH and support the concept of environmental justice.

Health Care Without Harm, American Nurses Association, U.S. Environmental Protection Agency's Office of Pollution and Toxics, and several progressive hospital consortiums sponsored SETTING HEALTH CARE'S ENVIRONMENTAL AGENDA CONFERENCE in October, 2000. Participants examined environmental issues facing health care, possible solutions, and impediments to the solutions.

The issues and impediments are weighty but solutions are possible and there are many who are eager and willing to work on them. The solutions will come more quickly as more join in the effort.
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Title Annotation:Independent Study
Publication:ISNA Bulletin
Geographic Code:1USA
Date:Aug 1, 2009
Words:4720
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