High Concentration Destruction of Schedule II Drugs with NEAT (NT7 + Peroxide)

Matthew Mills, PhD.

Summary

In this study Sudoc and a reverse distribution company utilized a third-party analytical laboratory to investigate the potential of Sudoc catalysts combined with hydrogen peroxide to degrade a mixture of Schedule II drugs in concentrations that would simulate those in a pharmaceutical waste collection environment. Extensive degradation was seen for four of the five compounds, and partial degradation for the fifth using Sudoc catalyst and hydrogen peroxide in just four hours. Sudoc’s technology outperformed activated carbon for the removal of oxycodone and hydrocodone and had comparable performance for morphine and testosterone. These results were achieved in 1/12th the time of the activated carbon treatment.

Introduction

Unused or expired pharmaceuticals are a distinct environmental challenge. This is especially true for Schedule II drugs given the legal scrutiny. For end users, there still does not exist an adequate disposal method of unused drugs except for facilities such as pharmacies or police departments that offer secure pharmaceutical deposit locations. When full, the waste pharmaceuticals are collected by a reverse distributor and sent to an incineration facility for disposal. Unfortunately, there are not many DEA-approved incineration facilities across the country, and there are strict requirements around transportation of controlled substances, like a requirement for two personnel to be with the collected waste at all times. If a more efficient disposal method was able to be implemented at the collection source this could alleviate logistical burdens and provide a better environmental outcome.

In determining whether a disposal technology is sufficient for controlled substances, the DEA declares that the substance must be irretrievable. However, they leave it up to the technology provider to show that this is the case, as they do not certify waste disposal technologies. Most existing collection technologies on the market rely on capture by activated carbon or encapsulation by a material like a gel. This is subject to some scrutiny, as the sequestered compounds are still present in the mixture and could potentially be retrieved. This is where a technology like TAML/peroxide could provide a large market advantage because, upon oxidation of the controlled substance, it no longer exists in any retrievable form.

Results

The percent removal of the five compounds at final treatment time, 48 hours for activated carbon and 4 hours for TAML, can be seen in Table 1. Figure 1 compares the rate of removal of hydrocodone bitartrate for each of the applied treatments. Several observations stand out from these data. First, unsurprisingly, activated carbon is slow to work. Even at the incredibly high treatment dosage of 160 g/L of activated carbon less than 50% of the target compounds were removed after 2 hours. It should be noted that the barbital measurements at 2 hours are negative due to an unknown instrumental artifact. The second observation is that TAML/ peroxide outperformed the other two treatments for oxycodone and hydrocodone, even when comparing the 48 hour treated carbon samples. Coconut shell activated carbon outperforms TAML/peroxide on morphine and testosterone by about 10% each. All the treatments struggled to remove barbital from solution, but this was the one compound of which the TAML/peroxide treatment performed the worst. However, given that 18% removal was seen after 4 hours it is possible that the conditions could be further optimized for removal of barbital.

One significant unknown in this experiment is the extent of degradation on the compounds of interest. Only seven equivalents of hydrogen peroxide were added to the reaction mixture. This should be enough to convert the starting materials into their oxidized forms, but not for full mineralization, which would take 20-30 equivalents of hydrogen peroxide. If multiple oxidations are performed on the same compound, this would leave fewer equivalents of hydrogen peroxide for initial oxidations of the test compounds. Additionally, at the tested concentration of hydrogen peroxide catalase-like activity is known to occur.1 This could consume hydrogen peroxide as well. Slow addition of hydrogen peroxide should favor the desirable degradation reactions as opposed to production of oxygen and yield better performance.

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REFERENCES

1. Ghosh, A.; Mitchell, D. a; Chanda, A.; Ryabov, A. D.; Popescu, D. L.; Upham, E. C.; Collins, G. J.; Collins, T. J.; Pennsyl, V. Catalase - Peroxidase Activity of Iron ( III ) - TAML Activators of Hydrogen Peroxide. J. Am. Chem. Soc. 2008, 130 (Iii), 15116–15126.