A continuous collection system for household pharmaceutical wastes: a pilot project.

ABSTRACT

A 5-month "self-serve" pilot project was implemented to properly dispose of old and unwanted prescription and nonprescription medications. Obstacles encountered during the program included reluctance by major drug store chains to participate, regulatory and legal restrictions on pharmaceutical handling, and collection of detailed data from participants. Despite these difficulties, a total weight of 305 lb of discarded pharmaceuticals was collected during the pilot program period from an estimated 500 participants. A survey of participants indicated that discard of pharmaceuticals to the sanitary sewer, a newly discovered environmental hazard, is commonplace, with approximately 50% of participants using this method previously. The average age of the patients using the disposed medication was approximately 64 yr old, with the large majority being above 50 yr in age. The majority of participants learned of the program through newspaper advertisement. The average age or time after purchase of the medication was approximately 3 yr, and the primary purpose cited for its disposal was that the medication had exceeded its expiration date.

INTRODUCTION

The development of a multitude of medications for both human and animal use, plus a plethora of personal care products, such as shampoos, perfumes, and sunscreens, has increased the subtle release of anthropogenic chemicals to the environment. Beginning in the 1970s, and more actively in the past decade, scientists have revealed the ability of pharmaceuticals to enter the environment and remain there. (1-4) Reports have developed new terminology for the emerging pollution waste stream. Daughton and Ternes (5) have created the most widely encompassing term, "pharmaceutical and personal care products" (PPCPs). Sedlak et al. (6) created the term "pharmaceutically active compounds," and Fisher and Borland (7) recently described pharmaceutical pollutants as "feral pharmaceuticals."

Pharmaceuticals in the Environment

Concerns about medication disposal were previously limited to preventing the accidental poisoning of children or animals when the medication was discarded. This resulted in the common practice of flushing pharmaceuticals into the sewage system and throwing them into the trash. These disposal practices, combined with patient excretion of pharmaceuticals and their metabolites, has resulted in domestic sewage being the most commonly identified source of PPCPs into waterways. (8) Once in the domestic sewage, it is the responsibility of the sewage treatment plant to remove pollutants from the wastewater. Wastewater treatment plants, however, are designed primarily for the removal and treatment of natural human excrements and not the various anthropogenic substances such as PPCPs that become part of the wastewater. An extensive study of German sewage plants for 14 common drugs indicated a range of removal efficiency of 7-96%, depending on the medication. The average for all 14 drugs was approximately 60%. (9) Other reports indicate removal efficiencies of 38-80%. (7)

In the environment, concerns over pharmaceuticals' ability to influence wildlife and possibly change biological systems have emerged. The concentrations in the environment are very low, often below the therapeutic value of the substance, commonly at parts per billion (ppb) and parts per trillion. (5) These concentrations within the environment can be pseudopersistent, that is, they remain in the environment for long periods of time because of their continual low-level introduction into the environment.

Pharmaceutical Disposal Regulation

Approximately 50 new drugs enter the U.S. market every year. (10) With the introduction of each new medication, a potential new waste for disposal is also introduced. Past regulation of pharmaceuticals has focused on their efficacy and safety for use. Awareness of their environmental impacts has only recently been realized. In the United States, the Federal Interagency Task Group on Pharmaceuticals and Personal Care Products was formed in September 2004. In Canada, the Environmental Impact Initiative was formed in 2001, and in Japan the process of formulating a plan for environmental risk assessment of pharmaceuticals with sales above 1 t/yr is under way. (10) However, these are emerging efforts, and regulations concerning final disposal of pharmaceuticals are meager.

The European Medicines Agency (EMEA) is the body of the European Union responsible for the protection and promotion of public and animal health through the evaluation and supervision of medicines. In 1999, in response to rising evidence of pharmaceuticals in the environment and their impacts, the EMEA began drafting environmental risk assessment procedures to accompany new pharmaceutical applications in Europe. The proposed European guidance is the first to include long-term ecotoxicity testing, as well as to consider the environmental effects from extremely low concentrations of bioactive substances, such as endocrine disruptors. The U.S. Food and Drug Administration (FDA) is the federal agency responsible for the regulation of pharmaceutical development and usage in the United States. The FDA through the National Environmental Policy Act of 1969 requires that environmental assessments must be submitted as part of certain applications when the expected introduction concentration of the active ingredient in the aquatic environment exceeds 1 ppb. Examples of pharmaceuticals with wastewater treatment concentrations above 1 ppb are given in Table 1.

Many pharmaceuticals are narcotics, depressants, and stimulants manufactured for legitimate medical purposes but with the potential for abuse. To prevent their abuse, these pharmaceuticals have been designated as "controlled substances" and brought under legal control through the Drug Enforcement Agency (DEA) and the Controlled Substances Act. As controlled substances, the DEA requires special handling and distribution of these drugs, including documentation of the final destruction of the waste pharmaceutical. The DEA does not allow pharmacies, reverse distributors, or disposal companies to accept controlled substances once given to the prescription user, resulting in unused household medications to be either flushed into the sewage system or thrown in the trash. The number one prescribed pharmaceutical in the United States for each year from 2002 to 2004 was the controlled substance hydrocodone. (11) Hydrocodone has been measured in surface water in a concentration ranging from 6 to 13 ng/L. (12)

U.S. Environmental Protection Agency (EPA) is the primary agency responsible for regulation of the disposal of solid wastes in the United States, including unused and discarded pharmaceuticals. Specific EPA regulations pertaining to discarded pharmaceuticals do not exist. Thus, under EPA regulations, pharmaceuticals are treated as any other solid waste, and the eventual fate of pharmaceuticals can be affected by multiple other regulations and regulatory agencies. Some pharmaceuticals may be considered or managed as medical waste, which is generally defined under state regulations and differs among various states.

In each state, a board of pharmacy or its equivalent regulates pharmacists, pharmacies, and prescription drugs and devices to protect consumer health and safety. Once dispensed, the improper storage, deterioration because of age, or tampering could alter the quality of medications. As a result, the return of pharmaceuticals for reuse is often prohibited, and many states forbid the possession of a prescription pharmaceutical by anyone other than the original prescribed patient. This limits the role pharmacists can play within the United States in receiving unwanted household medications for disposal.

PPCP Disposal

The growing pharmaceutical waste stream is indicated by the ever-expanding use of prescription medications and over-the-counter preparations. Between 1988-1994 and 1999-2000, the percentage of Americans who reported using any prescription drug during the past month increased from 39% to 44%. During the same period, the percentage of persons who reported using three or more drugs in the past month increased from 12% to more than 17%. (13)

Nonresidential Generators: Hospitals, Pharmacies, and Healthcare Facilities. Typical generators of unused pharmaceutical wastes outside of consumer use are hospitals, medical and dental offices, commercial pharmacies, and other healthcare facilities. In a survey of community and hospital pharmacies, Kuspis and Krenzelok (14) found that only 3% of the pharmacies surveyed did not have a specific unused medication disposal plan. The method most often used was returned to the producer. However, for nonreturnable medications, the pharmacies cited incineration (15%), hazardous waste disposal contractor (17%), or conventional waste disposal (trash or sewer flushing, 68%). (14)