Fate of selected drugs in the wastewater treatment plants (WWTPs) for domestic sewage

Abstract

The wide diffusion of Emerging Organic Micropollutants (EOMs) in the environment is receiving increasing attention due to their potential toxicological effects on living organisms. So far, the Wastewater Treatment Plants (WWTPs) have not been designed with the purpose to remove these contaminants; therefore, they can represent the major source of release into the environment both through the effluent and the wasted sludge. The fate of EOMs in the WWTPs is still not completely known; further investigations are therefore needed to assess if it is possible to exploit the existing treatment units to reduce EOM concentrations or which processes must be implemented to this purpose. Among the wide class of EOMs, the present study focused on the following drugs of abuse: amphetamine (AM), methamphetamine (MET), 11-nor-Δ9-THC-9carboxy (THC-COOH) and benzoylecgonine (BEG). Presence and removal efficiency of these drugs in the activated sludge tank of a WWTP for domestic sewage was investigated through analyses at both full-scale and laboratory scale. Determinations conducted in the full-scale WWTP highlighted that, among the searched drugs, AM was found to be the most abundant in the influent and effluent of the biological oxidation tank, while 11-nor-Δ9-THC-9carboxy was present at the lowest concentration. Some removal took place in the units prior to the oxidation tank, although the main reduction was observed to occur in the biological oxidation reactor. All the drugs showed a wide variability of the measured concentrations during the week and the day. Taking into account results from both full-scale observations and batch tests, removals in the biological reactor were found within the following ranges: 33-84% for AM, 33-97% for MET, 33-57% for BEG and 29-83% for THC-COOH. These removals were due to a combination of adsorption and biodegradation mainly, while volatilization did not play a significant role. Other processes, e.g. hydrolysis, were likely to occur.

Occurrence, seasonal variations and removal of Organic Micropollutants in 76 Wastewater Treatment Plants

“…The target OMPs investigated in the survey were selected being representative of some of the most diffused classes of OMPs in the domestic wastewater (illicit drugs, pharmaceuticals and steroids), as referred by the scientific literature. Furthermore, for other classes of OMPs the analytical methods still present some uncertainties, whereas for the selected pollutants the research group has been able through previous studies to assess reliable detection methods (Boni et al, 2018a;Chiavola et al, 2019Chiavola et al, , 2017Chiavola et al, , 2016. Particularly, within the class of illicit drugs and their metabolites, the following compounds were investigated: Benzoylecgonine (BE), 11-nor-carboxy-Δ9tetrahydrocannabinol (THC-COOH), Amphetamine (AM), Methamphetamine (MET).…”

A critical review on the detection, occurrence, fate, toxicity, and removal of cannabinoids in the water system and the environment

“…Collected water samples may be kept in either high-density polyethylene (HDPE) or amber glass bottles at -20 or 4 °C until further use. In previous studies, sludge and sediment samples were collected as grab samples and were stored at 4 °C until further processing ( Black et al 2019 , Chiavola et al 2019 , Mastroianni et al 2016 ).…”

Occurrence and removal of illicit drugs in different wastewater treatment plants with different treatment techniques

“…The elimination efficiency of illicit drugs varied compound by compound in WWTPs. For instance, the removal rate of amphetamine (AMP) and cocaine (COC) was more than 90%, while the removal efficiency of 3,4-methylenedioxymethamphetamine (MDMA) or methamphetamine (METH) was below 50% [14][15][16][17]. The majority of illicit drugs cannot be completely removed in the traditional WWTPs, and a great number of illicit drugs were able to get in the surface water, groundwater and drinking water sources with the discharged effluent [18].…”