Many HDs are excreted in urine, stool or emesis. In addition, HD can be found in semen, saliva, sweat and emesis although there is less drug-specific information pertaining to those forms of excreta. Contaminated linens are also a potential source of exposure to nurses and ancillary hospital staff. (More information on linens can be found HERE.)
In healthcare settings, personal protective equipment (PPE) (consisting at a minimum of 2 pair of ASTM 6978-05 tested gloves and a chemotherapy resistant gown) must be used when handling excreta to prevent inadvertent exposure. In situations where splashing can occur (e.g., emptying a urinal or rinsing a commode), face and eye protection should be worn (NIOSH, 2016).
The difficult question is how long after HD administration must PPE be worn?
The answer is: it depends.
The majority of HDs are eliminated within 48 hours. However, some continue to be excreted for longer periods. Excretion is not linear (i.e., more drug may be eliminated during the first 24 hours than the remaining 72), and is influenced by a number of unpredictable interpatient variables. In general, it takes 4 to 5 "half-lifes" to completely elminate a circulating drug since elimination is not linear--especiallyi for toxic metabolites. The table on this website provides the half-life (when available) as a general guide.Therefore, guidance as to duration of PPE is always approximate and is not a precise science.
It is also fair to assume that exposure to excreta is less dangerous than exposure to actual drug (during compounding or administration). However, one case study reported by Kusnetz and Condon (2003) describes a HCW who, on 2 separate occasions, had allergic reactions to urine from a patient who had received doxorubicin and vincristine. While neither of these drugs are known to vaporize at room temperature, the urine itself could act as a vehicle for the HDs, resulting in drug inhalation. During both incidents, the employee was wearing a gown and gloves. While no studies have been conducted to look at this specific type of exposure risk, it is still a cause for concern.
Further complicating the picture, some drugs are excreted as unchanged, inactive metabolites or active, hazardous metabolites. Few studies look at the mutagenic properties of excreted drugs as this is not a priority for pharmaceutical companies during drug development and is not an FDA requirement. Clearly, there are more questions than we have concrete answers.
That being said, guidance for wearing PPE is still useful.
The table below contains agents used for cancer treatment. Excretion information is not available for all drugs, and published data does not always differentiate between active drug, active metabolites or non-hazardous metabolites.
Serum half-life (t1⁄2) is provided when available, although as stated above, does not directly correlate with excretion which is dependent upon drug kinetics and interpatient variability.
Therefore, nurses are advised to use judgement in determining optimal duration for PPE.
As a general guide, the duration of PPE should be 3-5 times the t1⁄2.Where data not provided, 4 times the t1⁄2 was used.
Monoclonal antibodies are not excreted via the same pathways as small molecule drugs. Note that excretion of the linked portion of conjugated MAbs is also highly variable. For a general discussion on monoclonal antibodies within the context of hazardous drug safety, click here. Conjugated MAbs are included below where data exists for the unlinked drug.
Sources for table:
Micromedex©; Safe Handling of Hazardous Drugs (Polovich & Olsen, 2018); https://go.drugbank.com/drugs; manufacturer's prescribing information, Oncology Nursing Drug Handbook (Wilkes & Barton-Burke, 2021), ISOPP, 2007, Pharma-Cycle, LLC., and data from published phase I studies.