Healthcare workers are often at high risk of hazardous drug exposure; ironically some medications upon which we rely for healing can be potentially as deadly as the diseases they are combating.
This duality applies to treatments involving hazardous drugs. The National Institute for Occupational Safety and Health (NIOSH) in the United States categorises drugs as hazardous if “studies in animals or humans indicate that exposures to them have a potential for causing cancer, developmental or reproductive toxicity, or harm to organs.” The vast majority of medications classed as “hazardous” are prevalent in oncology treatment – specifically, chemotherapy drugs.
Origins and awareness
Chemotherapy drugs are highly toxic, containing antineoplastic agents whose origins can be traced to the development of chemical warfare during the First World War. The same deadly ingredients, unleashed with such devastating effect a century ago (specifically in the form of mustard gas) are now regularly being used to combat cancer. Indeed, it was the autopsies of soldiers killed by mustard gas in WWI that revealed a decrease in the white blood cell counts, leading researchers to experiment with nitrogen mustard as a treatment for various types of lymphomas and leukaemia.
However, these chemicals have the potential of being just as dangerous to the healthcare workers attempting to save lives. Contemporary studies conducted in the United States, Asia and Europe have confirmed that exposure to hazardous drugs can lead to a variety of complications due to the inherent mutagenic, cytotoxic and/or carcinogenic nature of these drugs. These can range from skin irritations and rashes to birth defects and miscarriages and, in extreme cases, even cancer.
Given the documented risks of these drugs, it did not take long for manufacturers to recognise the need to protect workers involved in handling chemotherapy drugs. Production quickly moved from open-plan factories, void of any form of safety precaution, to sophisticated facilities comprising several layers of clean rooms, divided with pressure differentiators to ensure that hazardous substances are not able to escape.
At present, most of this production is automated to further reduce the risk of hazardous drugs to workers, and subsequently others, from becoming contaminated. The limited personnel who directly operate in these production centres often resemble astronauts, wearing completely sealed and pressurized suits.
Only recently has an awareness for the need to protect healthcare workers in hospitals, pharmacies and infusion centres grown. Over the last few decades, numerous studies have been performed to assess the existence of hazardous drug exposure within healthcare settings. Although these studies were conducted in various countries employing varied approaches, the results have been universally conclusive: traces of hazardous drugs have been found all over hospitals – including areas where they have never been administered – and even in the blood and urine of hospital staff. There is now no doubt that hazardous drug exposure is a very real, collective issue.
Responses to these findings have varied by country and locale. Even today, the debate is still ongoing with a lack of a satisfactory solution that can fully address the problem of hazardous drug exposure. Nevertheless, some key milestones have been achieved.
In 2004, NIOSH issued an alert (Preventing Occupational Exposure to Antineoplastic and Other Hazardous Drugs in Health Care Settings) mandating the procedures and equipment to be used in handling high risk drugs. In the past, nurses routinely both compounded and administered drugs in the wards. Today, the majority of hospitals in most countries have dedicated pharmacies where hazardous drugs are prepared and compounded by licensed pharmacists before handing off to nurses for administration.
Protective measures must begin from the moment these drugs arrive at a hospital, continuing through to their storage, preparation, administration and eventual disposal. These safeguards include engineering controls, such as clean rooms and biological safety cabinets, as well as personal protective equipment (PPE), which range from gowns and double gloves to masks, goggles and Closed System Transfer Devices (CSTDs).
That same year, the European Union issued its Directive 2004/37/EC, addressing the “protection of workers from the risks related to exposure to carcinogens or mutagens at work.” However, the directive did not specifically address the use of hazardous materials in the healthcare space. Consequently, no European-wide legislation or standards have currently been set for the administration of hazardous drugs, leaving some countries to implement their own guidelines while others have failed to address the issue at all.
In the US, organisations such as the American Society for Health-System Pharmacists (ASHP) and the Oncology Nursing Society (ONS) were quick to adopt the NIOSH alert or issue their own variation, resulting in a greater awareness, particularly among the younger generation of healthcare workers around the need to educate and protect against hazardous drug exposure. European health authorities have been slower to react. Indeed, it is only relatively recently that extensive standards and regulations were prescribed for British pharmacists.
While pharmacists were the first to recognise the true nature of these drugs due to repeated compounding and preparation in their concentrated form, nurses, who generally handle diluted forms of the drugs, were the last to be made aware and begin taking protective measures.
Recent statistics indicate that health problems among oncology nurses are significantly higher in comparison to other healthcare workers that handle hazardous drugs, indicative of reduced safeguarding protocols. A growing number of nurses involved with the handling of cytotoxic chemotherapy drugs across the UK have reported symptoms ranging from substantial hair loss to an uncommonly high number of miscarriages, according to a research carried out by MindMetre in February 2017.
Closed System Transfer Devices
Independent studies published in Europe, Japan and the United States have concurred that hospitals are at risk of contamination from the moment hazardous drugs enter the facility, through administration to patients and finally, disposal. Furthermore, while existing safety precautions —including both engineering controls and personal protective equipment— currently implemented in hospitals offer a high level of protection, they are not sufficient in completely eliminating contamination from hazardous drug vapours, aerosols and/or liquids.
CSTDs have been proven to significantly reduce surface contamination in pharmacy and hospital settings, leading to increased calls in academic circles that their use be implemented for the entire drug journey, from reconstitution through to disposal. There are, however, some essential features necessary for a CSTD to be considered a true closed system. These key components include an internal needle that never leaves the system – thereby eliminating the risk of exposure from needle-sticks – and a locking system that prevents leaks between the needle and drug vial. Plunger contamination has been recently identified as a major route of exposure, an issue which a number of CSTDs have yet to address. To mitigate this route of exposure, a plunger rod which never comes into contact with the walls of the syringe barrel is required.
Following recommendations from NIOSH, ASHP and ONS, the adoption of CSTDs in US hospitals and pharmacies has gained considerable momentum. In European countries, the adoption of such protocols has been slower and less cohesive. While some health authorities, such as Spain’s National Institute of Safety and Hygiene at Work, do reference the NIOSH guidelines, a number are yet to properly define the requirements of truly closed systems for hazardous drug use. For example, the UK’s Health and Safety Executive stipulates the use of “totally enclosed systems where reasonably practicable,” yet neglects to specify the definition of a truly closed system.
However, despite the additional layer of protection afforded by Closed System Transfer Devices, recent studies indicate that many CSTDs currently used in hospitals – including some with FDA or CE certification – do not protect against all routes of exposure. Due to this reality, when hospitals and healthcare facilities seek to introduce CSTDs into their practices, they should ensure the device is truly a closed system, in every sense of the word.
EU Directive available here
Marino Kriheli is co-founder at Equashield