HAZARDOUS DRUG EXPOSURES IN HEALTHCARE

Risk Management for Hazardous Drugs

Overview

Hazardous drugs used to treat patient illnesses can harm unprotected healthcare workers in their workplaces. To protect healthcare workers, it is recommended that workplaces assess the hazards specific to their workplace and develop hazard control strategies to mitigate those hazards. These may include use of engineering controls, such as ventilated hoods and enclosures; adoption of administrative controls, such as establishing safe handling policies, training, and routine training reviews for potentially exposed individuals; and supplying personal protective equipment (PPE), such as chemotherapy gloves and gowns, when appropriate.

Factors affecting the risks posed by hazardous drugs

The chance that hazardous drugs will harm workers in healthcare workplaces, and the severity of the harm, depends on several factors, including:

• A drug’s toxicity: This refers to the type of harm a drug can cause to a person’s health. For example, cytotoxic drugs are used to kill cancer cells, but they can also cause cancer or other harm to healthcare workers who work with or handle them without adequate protection. Some drugs may harm a person’s ability to have healthy children.
• A drug’s potency: Some drugs are very toxic at very low doses, while other drugs may cause harm only when a worker is exposed to very high doses. Exposure to high doses of hazardous drugs is uncommon in most healthcare settings.
• Route of exposure: How workers may be exposed to a drug is an important factor to consider in developing strategies for controlling exposure. Workers can be exposed to hazardous drugs through breathing vapors, dusts, or aerosols, absorbing it through skin contact (for example, touching dust or liquid residue on surfaces), swallowing it, or accidental injection.
• A drug’s physical and chemical properties: The physical and chemical properties of drugs that influence their hazard include vapor pressure, physical state (solid, liquid, or gas) and molecular weight of the drug. Many drugs have very low vapor pressures, so inhaled vapor is not a route of exposure of concern for most drugs. However, drugs in liquid or powder form may be inhaled as aerosols, droplets or dusts. In addition, drugs may be absorbed through skin, especially if the skin is chapped, abraded or has cuts or scrapes. But skin contact alone does not necessarily lead to toxicity. For example, when a drug has a high molecular weight, like a monoclonal antibody, and its typical dosing regimen is via injection, the drug would generally be absorbed through intact skin very poorly. Therefore the likelihood that a worker would suffer harm from exposure is also very low. Of course, there may still be a risk of exposure to such drugs from accidental needle sticks or inhalation of dusts or droplets.
• Drug formulation: This refers to the form the drug takes for administration—such as a powder, liquid, capsule, or prefilled syringe. Like a drug’s physical and chemical properties, the formulation of the drug is an important indicator of the types of precautions needed to avoid exposure. Different risk management strategies are needed for powders than pre-filled syringes.
• Workplace activity: This involves how workers use and handle the drug in the workplace—such as administering the drug, compounding it, shipping it, or receiving it. Different activities have very different potential for healthcare worker exposure.

Regardless of their formulation, cytotoxic drugs used to treat cancer in patients are considered especially hazardous. These drugs have manufacturers’ special handling information on them that should be followed at all times. NIOSH also considers some drugs hazardous because they meet NIOSH criteria for hazardous drugs. These include drugs that cause cancer; drugs that harm a worker’s organs, like liver, brain or kidney; drugs that may affect a worker’s ability to successfully conceive and have healthy babies; drugs that could harm women who are pregnant or may become pregnant; and drugs that could put the health of the fetus at risk. Some drugs handled or used in the healthcare workplace may also be a concern for women who breast feed, because drugs and chemicals workers are exposed to in the workplace may be found in breast milk.

Steps you can take to protect workers

No single approach can protect all workers in healthcare workplaces against all hazardous drugs. These steps, however, can lessen the chance that hazardous drugs will do harm:

• Clearly label all hazardous drugs so workers will know to carefully handle them.
• Do not use automated counting machines for hazardous drugs. The machines can produce powder and contaminate the work area.
• Use liquid formulations when possible to avoid crushing tablets or opening capsules.
• When possible, avoid cutting, crushing, or otherwise manipulating pills or capsules. This might produce powder that can contaminate a workplace and may expose workers.
• When manipulating hazardous drugs, use effective engineering controls and personal protective equipment.
• Use effective engineering controls and personal protective equipment when you compound a hazardous drug.
• Consider relevant factors when determining appropriate hazard control strategies. For example, administering unopened, intact tablets and capsules may have lower risk of exposure than preparing syringes or IV bags of injectable drugs.

Managing healthcare workplace risks from hazardous drugs

The table below provides general guidance for some of the possible scenarios where hazardous drugs are handled in healthcare settings, but it cannot cover all possible situations. The actual risk to workers handling hazardous drugs is governed by many factors. In addition to proper use of engineering controls and personal protective equipment, the risk to workers in different healthcare workplace scenarios may be altered by intrinsic properties (potency, chemical and physical properties, and formulation) of the drugs used including molecular weight, volatility, and skin permeability. A site specific risk assessment including consideration of all of the relevant factors may suggest different risk management procedures for a specific workplace scenario. Whenever possible, NIOSH encourages employers to do a site-specific risk assessment that informs effective risk management procedures. Section 16 of the drug prescribing information (drug package insert) also offers advice for safely handling some hazardous drugs.