Analysis of amphetamine and methamphetamine as emerging pollutants in wastewater and wastewater-impacted streams

Abstract

The identification and quantitation of the non-ecstasy amphetamine-type stimulants (ATSs) amphetamine and methamphetamine in lakes, rivers, wastewater treatment plant influents, effluents, and biosolids are reviewed. Neither monitoring nor reporting is required of these ATSs, which are considered emerging pollutants, but they have been identified in the environment. Amphetamine and methamphetamine enter our water supply by human excretion after legal or illegal consumption and via manufacturing in clandestine laboratories. Analytical methodology for sampling, sample preparation, separation, and detection of ATSs is discussed. Reported occurrences of ATSs in the environment and their use in municipal sewage epidemiology are noted. Future research needs that challenge applications of analytical techniques are discussed. The review focuses on research reported from 2004 to 2009.

Introduction

The phrase “emerging pollutants” can be defined as substances that are not presently known to cause impairments in water systems but that have characteristics such as the ability to bioaccumulate, persistence in the environment, and toxicity and potentially impact the integrity of the water [1]. Neither monitoring nor reporting is required of these substances, but they may still be present in the urban water cycle. Much of the peer-reviewed literature has focused on pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs), but recent research has also included groups of illicit drugs such as cocaine, opioids, opioid pharmaceuticals, cannabis, and amphetamine-type stimulants (ATSs). Although drugs in all of these categories have been found in environmental samples, this review will focus on analytical determination of amphetamine and methamphetamine.

Amphetamine and methamphetamine enter our water supply by human excretion after legal or illegal consumption and via manufacturing in clandestine laboratories. Amphetamines and methamphetamines are sometimes legally prescribed for certain medical conditions such as attention deficit hyperactivity disorder and exogenous obesity; therefore, their presence in wastewater cannot be attributed solely to illegal consumption. However, according to the United Nations Office of Drug and Crime (UNODC), the global problem with clandestine ATS markets is worsening, with estimates showing that between 230 and 640 metric tons of amphetamine-group substances (excludes ecstasy-group substances) were manufactured in 2007 [2].

Approximately 62% of methamphetamine [3] and 30–40% of amphetamine [4] consumed is excreted in urine within 24 h of an oral dose, and both amphetamine and methamphetamine are primarily excreted as the intact drug [5]. Once these drugs enter the wastewater treatment plant (WWTP) as influent, they can potentially enter surface or groundwater from inadequately treated WWTP effluent, wet-weather run-off, landfill seepage, contaminated streams and lakes, drainage from fields irrigated with effluent, and even from effluent used to recharge aquifers [6]. Jones-Lepp et al. [6] also noted that unlike non-polar pollutants of historic concern, these polar compounds are not readily sorbed to the subsoil, increasing the potential to enter surface and groundwaters.

The purpose of this manuscript is to compile a review of state-of-the-art analytical methodology used for sampling, sample preparation, separation, and detection of ATSs in environmental samples. Reported occurrences of ATSs in the environment are noted, and future research needs that challenge applications of analytical techniques are discussed.