Browsing by Author "Mustapha, A.O, Coffey, M and Birkett, J.W."

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Degradation of cocaine and benzoylecgonine in sewage sludge batch tests.
    (Fountain University, Oshogbo., 2017-06-30) Mustapha, A.O, Coffey, M and Birkett, J.W.
    The degradation studies of cocaine and its principal metabolites, benzoylecgonine, as emerging pollutants were carried out using various sludge types collected from the RAF Molesworth Sewage Treatment Work (STW) to determine their distribution and persistence in aquatic environment. The methodology, initially characterized the various sludge types before the laboratory batch tests were carried out at different temperatures and times. The results, after 3 hours equilibration of batch samples, showed the removal rates for cocaine and benzoylecgonine to be 91.0% and 90.6%, respectively. The partition coefficients (Kd) for the two substances ranged from 2.7 – 31.9 Kg L-1. Degradation of compounds was found to be both biotic and abiotic and the two processes produced many short chain compounds and several metabolites that include cocaethylene and ecgonine methylester. Also at 4 ± 0.5o C, the degradation of substances occurred slowly, at 5 and 10% but was relatively greater at 19 ± 0.5o C. Compounds degradation was also influenced by both extracellular and intracellular enzyme activities. The batch study is an innovative method in calculating degradation rates of compounds from sewage treatment works. The capabilities of generating removal rates of drugs have also been clearly demonstrated in this work and can be applied to any organic compounds in real life (STWs) situations.
  • Thumbnail Image
    Item
    Degradation of heroin, morphine and 6- monoacetylmorphine in sewage batch test.
    (Ladoke Akintola University of Technology, Ogbomosho, 2018-01-16) Mustapha, A.O, Coffey, M and Birkett, J.W.
    The increasing global consumption of some narcotic drugs or drugs of abuse as reported by the United Nations Office of Drugs and Crime (UNODC) is a new source of emerging pollutants that is currently threatening the aquatic ecosystem due to associated toxicity levels. Apart from pharmaceuticals and personal care products, drugs such as heroin, morphine and 6- monoacetylmorphine have been found in the environment thereby worsening the already escalating situations. The persistence of pollutants in aquatic environment is due to their non – biodegradation owing to their hydrophilicity/lipophilicity properties. The pollutants principally reach the environment via Municipal Sewage Works or by direct dumping. Therefore, the degradation studies of drugs at different temperatures and times are apt and would improve removal approach using various sludge types. The analytical method used to determine their biodegradability involves initial characterization and after 3 hours equilibration, the removal rates were then measured for heroin (97.9%), morphine (99.7%) and 6-monoacetylmorphine (93.3%). The three substances have the partition coefficients (Kd) that ranged from 1.2 – 68.1 Kg L-1. At 4 ± 0.5o C, the degradation of compounds occurred slowly, but relatively greater at 19 ± 0.5o C to between 5 and 10%. This paper therefore highlights the degradation studies of heroin and its principal metabolites and clearly demonstrated removal method at different laboratory conditions and times. The conceptual approach is aimed to achieve the best removal conditions to reduce the problems of chemical pollution due to persistence or non-degradation of these classes of drugs in the environment for the first time, a novel aspect of the work.
  • Thumbnail Image
    Item
    Mass balance calculations of illicit drugs in Stoke Bardolph Sewage Treament works, United Kingdom
    (Hikmah University, Ilorin, Kwara State., 2015-08-26) Mustapha, A.O, Coffey, M and Birkett, J.W.
    Work encompassed in this study directly measures illicit drug removal rates in laboratory studies. Researchers employed removal rate data in calculating mass balances in sewage works which is an improvement over prior studies where assumptions on removal rates at Sewage Treatment Works were made. The batch tests data enabled determination of degradation of the compounds at different temperatures and times, using various sludge types after characterization. Mass balances for the Stoke Bardolph Sewage Treatment Works were constructed using the removal rate data from the batch studies. Final effluent concentrations of 10.0 ng L-1 (morphine), and 80.0 ng L-1 (6-monoacetylmorphine), were recorded after a total of 8 hour hydraulic times (8 HRT) from an initial influent concentration of 50 mg L-1. A projected influent concentration of morphine (1.4 g L-1) at Stoke Bardolph was derived from back-calculating measured final effluent concentrations using the same mass balance approach.