Unsafe Sharps Disposal Among Insulin-Using Patients With Diabetes Mellitus: An Emerging Global Crisis

Abstract

Approximately eight billion therapeutic injections are administered outside of medical treatment facilities annually. The management of diabetes mellitus (DM) includes self-monitoring of blood glucose levels and administration of insulin and injectable non–insulin-related medications. The lancets, needles, and syringes used for DM management are categorized as medical sharps. Improperly discarded medical sharps can cause needlestick injuries in unsuspecting individuals and thereby pose a considerable public health risk. Release of these items into the environment will likely increase with the rising worldwide prevalence of DM, and a public safety crisis will emerge if proper disposal measures are not emphasized. This article reviews the literature from various geopolitical regions and describes how a substantial number of patients with DM improperly discard their sharps. Data support the need to develop multifaceted and innovative approaches to reduce risk associated with improper disposal of DM-related medical sharps into local communities.

Introduction

Media reports and images from the 1980s showed needles washing ashore on public beaches and illustrated the dangers of improper disposal of medical sharps. ¹ The World Health Organization estimates that nearly 16 billion injections are administered annually; ² of these, nearly eight billion are administered outside of health care facilities (e.g., in the home or workplace). ³ The number of used needles (termed medical sharps) discarded into household garbage was estimated to increase by nearly threefold from 2001 through 2011. ³ Improperly discarded needles present a risk to waste industry workers who sort recyclables. Nearly 1500 needlestick injuries are estimated to occur annually at material recovery facilities in the United States, and the associated treatment, prophylaxis, and monitoring costs are approximately $2.25 million. ³ However, risk is not only to workers at the material recovery facilities but also includes workers collecting the waste from households and landfill operators. In developing countries waste pickers are prevalent both at the point of generation (i.e., sorting through the rubbish bags on the kerbside on the day of collection) as well as at the landfill site. Improper home disposal also places home health workers at risk of needlestick injuries. ⁴

Treatment of diabetes mellitus (DM) includes self-monitoring of blood glucose and administration of insulin and injectable non–insulin-related therapeutics. Medical sharps associated with DM treatment can include lancets, needles, and syringes. In addition, insulin pumps and continuous glucose monitors (CGMs) may also generate medical sharps waste (e.g.,infusion sets and connecting needles). ³ As with other medical sharps waste, unless these items are carefully discarded after use, they could put an unsuspecting worker at a material recovery facility at risk for direct contact with biologic materials via a needlestick injury.

The problem of medical sharps waste generated during the course of DM self-management will likely continue to grow as disease prevalence increases. As of 2018, nearly 35 million people in the United States (10.5% of the population) had a known diagnosis of DM. ⁵ Globally, more than 420 million people have DM, and the prevalence is expected to increase to 570 million by 2030. ⁶ Because disposal of loose needles into the municipal solid waste stream is never acceptable, several organizations have published guidelines for the proper disposal of sharps at home. For instance, the US Food and Drug Administration (FDA) recommends placing used sharps into a sharps disposal container. If an FDA-cleared container is unavailable, a heavy-duty plastic household container can be used, although, depending on the thickness, it may not be safe.^{7 -9} The US Environmental Protection Agency has published its recommendations. ¹⁰ However, regulations for sharps disposal may vary by state, and these diverse recommendations could be challenging for patients who travel around the country. ¹¹

As DM prevalence continues to rise, the issue of medical sharps disposal becomes a potential global emerging environmental crisis, and international strategies to facilitate appropriate disposal must be developed. However, to improve sharps disposal practices among patients with DM, their current behaviors must be understood first. The purpose of this article is to summarize the studies that examined how patients with DM report disposal of their medical sharps.

Methods

We searched the literature to identify recent information, published since our previous study, ¹² on sharps disposal practices of patients with DM. With the assistance of a medical librarian, we searched PubMed and Embase by using the key terms “Diabetes Mellitus” with “Medical Waste Disposal” OR “Hazardous Waste,” OR “Waste dispos.” The search was limited to English-language articles published from 2016 to current year so that only the most recent publications could be reviewed. Discussion of results is provided by geographic region.

Results

Africa

In a survey of 132 outpatients with DM attending an outpatient clinic in Durban, South Africa, patients indicated that they were reusing needles 2 to 20 times. ¹³ When discarding sharps, 117 (89%) disposed of used needles directly into the household trash, 8 (6%) flushed needles down the toilet, and 4 (3%) used other methods (eg, buried the needles). Only 3 patients (2%) disposed of sharps properly (returned used needles in puncture-resistant containers to the hospital). Although most participants had received diabetes education, only 5 indicated they had received education and counseling regarding the correct methods of sharps disposal.

A second study from Africa on sharps disposal practices focused on 210 outpatients with DM in Ethiopia. ¹⁴ Patients had poor understanding of the risks associated with improper sharps disposal and had unsafe disposal practices.

Middle East

Investigators in Saudi Arabia surveyed 406 patients attending two diabetes specialty clinics about their knowledge, attitude, and practice of sharps disposal at home. ¹⁵ Knowledge about the dangers of needlestick injuries was noted by 92% of respondents, and 93% noted that sharps should be discarded in a safe manner. However, 79% indicated that they threw lancets and needles into garbage bags, and only 37% reported storing them in a plastic or tin container.

South America

A survey of 105 insulin-using patients with DM at a Brazilian primary care clinic showed that nearly 60% of patients disposed of sharps incorrectly. ¹⁶ Patients who had received education on safe disposal were 21 times more likely to dispose of waste properly.

A follow-up study by the same investigators examined insulin use and sharps disposal practices among 150 patients with DM. ¹⁷ In that analysis, the authors noted that syringes, needles, and lancets were disposed of incorrectly by more than 80% of survey respondents.

South Asia

Survey data on insulin use practices, including sharps disposal methods, were collected from 158 patients with DM treated at a teaching hospital in Sri Lanka. ¹⁸ The majority of respondents (68%) put their sharps into common household garbage bins. Other methods of disposal were sharps containers, toilet pits, a common public garbage dump, or incineration.

A study from Pakistan surveyed 375 insulin-using patients with DM who were recruited from five tertiary care centers. ¹⁹ The surveys indicated that 92% of insulin syringe users and 75% of insulin pen users disposed of their sharps by placing them directly in a household trash bin. In addition, 91% discarded their used lancets in the household trash bin. About half the patients reported being educated by their physicians about the proper disposal of sharps. The odds of safe disposal increased with patient education and their literacy levels. ¹⁹

Southeast Asia

A survey of 304 insulin-using patients with type 2 DM was conducted by primary care clinics in two districts in Malaysia. ²⁰ Only 35 patients reported delivering their sharps to a local health facility for disposal. However, when doing so the sharps were typically delivered in plastic bags and other non–heavy-duty containers.

The same investigators conducted a follow-up study of 132 insulin-using patients with type 2 DM receiving an educational intervention designed to improve safe handling of sharps. ²¹ One group was educated about proper sharps disposal and the second group was a control (no disposal education). During a three-month follow-up period, the intervention cohort showed a significant improvement (P < .001) in sharps disposal methods compared with the control cohort.

United Kingdom

A survey from a one health district showed a low percentage of safe disposal practices among patients with DM. ²² A randomly selected sample of 1348 adults with DM, obtained from the district population–based diabetes register, were surveyed regarding their sharps disposal practices, and 1201 responses were received. Lancets were loosely placed into household waste by 29.5% of respondents. In addition, 24.3% of syringes and 11.5% of needles were discarded directly into household waste. Disposal into household containers was reported for 35.1% of lancets, 34.1% of syringes, and 27.1% of needles. The remaining respondents used other means of disposal (eg, safety clip, incineration). ²²

United States

Insulin-using patients treated at an academic tertiary care endocrinology practice in New York were surveyed regarding their medical sharps disposal practices. ²³ Responses from 151 patients with DM were analyzed. The investigators defined sharps as syringes, pen needles, and lancets, and a sharp was defined as correctly handled if it was placed in either a designated sharps container or puncture-resistant container. The survey showed that only 59% of respondents disposed of sharps correctly and that the odds of doing so increased by nearly fourfold if patients had received proper instruction. ²³

Another study conducted in a private endocrinology practice in New Jersey surveyed sharps disposal practices among insulin-using patients. ²⁴ They specifically examined gender-based differences and the impact of attitude and education. Attitude was defined as the intent to use proper disposal practices. They reported that men of lower income followed safer disposal practices than men of higher income, older women had a more positive attitude toward safe disposal than younger women, positive attitude correlated with proper disposal practices, and individuals who received prior information engaged in safer disposal methods. ²⁴

We previously conducted a survey to assess patterns of sharps handling and disposal among insulin-using patients at our academic endocrinology practice. ¹² Ours was unique from the other studies reviewed here because it also included inpatients and patients using insulin pumps and CGMs. The survey was completed by 150 patients (94 outpatients, 56 inpatients). Of those who self-monitored blood glucose levels, 38% discarded lancets directly into the trash, as did 33% of those injecting insulin. No differences in sharps handling was observed between outpatient and inpatients. A longer duration of DM was associated with more unsafe disposal practices (P = .03). Insulin pump infusion sets and used CGMs were placed directly into the household trash. The majority of respondents (64%) indicated they had never received any counseling about how to safely dispose of their medical sharps waste.

Multinational Studies

Individual reports from various geopolitical regions illustrate the global issue with unsafe disposal of medical sharps by patients with DM. Multinational surveys have provide additional evidence of the global problem of improper medical sharps disposal. For instance, an analysis of questionnaires sent to 109 practices in France, Belgium, Luxembourg, Switzerland, and Tunisia and completed by 1070 respondents ²⁵ showed that 46.9% of needles, 49.9% of syringes, and 52.2% of lancets were placed directly into household garbage. For those who managed their DM in the workplace, 63% brought their medical sharps home for disposal, and 30% disposed of sharps directly into the trash in the workplace work.

In the largest study of its kind, data on insulin injection techniques and practices were collected from 13 289 insulin-requiring patients from 423 centers in 42 countries. ²⁶ Forty-eight percent of respondents indicated that they recapped needles and then threw them into the household trash. Another 40% then disposed of sharps into the community trash. Neither of the above studies included information on whether respondents had received education regarding proper sharps disposal.

Discussion

A review of surveys conducted on medical sharps disposal practices among DM patients reveals a common worldwide theme: patients typically do not dispose of their medical sharps in a safe manner. The mass of medical sharps discharged into the environment is expected to rise in parallel with the global increase in DM cases. Discharging DM-related medical waste into the environment without following the recommended disposal methods places the community at risk of needlestick injuries.

The studies of medical sharps disposal practices have several limitations. First, each study used a unique survey instrument, so the data collection methodologies were not standardized. Second, the data were self-reported, which raises the possibility that improper disposal practices could be underreported if respondents had concerns about possible criticism or reprisal. If this is true, the problem with disposal may actually be much greater than estimated. Third, surveys generally assessed home-based disposal practices. Extremely limited data have been obtained about medical sharps disposal in other venues, such as at work, when transiting through major transportation hubs (eg, airports, train and bus stations), at restaurants, or while vacationing.

The problem of unsafe medical sharps disposal is one that likely will require multilevel solutions. As indicated by some of the cited studies, patient education is key but often does not occur. Diabetes educators should be fully versed in their regionally specific guidelines for medical sharps disposal so that they can pass that information on to the patient. Enhanced point-of-care education is crucial but may not be sufficient as it will only touch a small number of patients. A larger public health campaign that emphasizes risk of improper disposal of medical sharps will be required. Such a campaign could describe safe sharps disposal methods and options, such as special municipal pickup services, designated drop-off centers, mail-back or exchange programs, or destruction of needles at home (and then safe disposal with the household trash).^10,27 However, the resources for safe disposal will not be universally available. Nongovernmental organizations, such as the Product Stewardship Institute, have promoted disposal models in which the manufacturers of pharmaceuticals and their associated sharps pay for and manage sharps take-back programs. ²⁸ Holding manufacturers accountable to design solutions through legislation may ultimately be needed.

The discharge of medical sharps waste into the community is a priority from a safety standpoint. However, medical sharps disposal should be considered in the broader context of the impact of all DM waste on the environment. DM care is associated with an unquantified mass of discarded unrecyclable and nonbiodegradable products, such as glass insulin vials and plastic pen devices. Unused medications may be discharged into the water stream (eg, by flushing down the toilet). Concerns about the environmental impact of dangerous and nondegradable DM products are now emerging. Some manufacturers of DM products are beginning to dedicate initiatives to solving this problem. ²⁹ The Diabetes Technology Society has recently launched its Green Diabetes Initiative, with the goal of reducing the mass of medical waste associated with diabetes care. ³⁰

Conclusion

Improper discharge of medical sharps into the community and surrounding environment is an important public health concern. Given the rising prevalence of DM, the sharps hazards generated through self-management strategies will likely increase in parallel, creating even greater public safety issues on a global scale in the future. Multifaceted and international efforts will be required to educate the public and improve safety. Extended producer responsibility needs to be enforced. Solutions will need all parties to be involved and not just the health care provider or nongovernmental organizations that are concerned with environmental issues.