Profiles in toxicology: Spotlight on Africa is a new web-series featuring toxicologists in Africa, in honour of TIAFT’s upcoming first international conference on African soil.

Dr. Ellen Mwenesongole
Dr. Ellen Mwenesongole

Botswana (from

Lorato Makanye, MSc student conducting SPE of waste water

Dr. Ellen Mwenesongole

Dr. Ellen Mwenesongole is a Forensic Science Lecturer at Botswana International University of Science & Technology (BIUST), where she has been involved in developing undergraduate and postgraduate forensic science courses as well as establishing a Forensic Chemistry research group. Dr. Mwenesongole holds a PhD in Forensic Science from Anglia Ruskin University (Cambridge, UK), and has also worked in toxicology, pharmaceutical and doping control laboratories.

Profiled as one of the Royal Society of Chemistry’s ‘175 Faces of Chemistry’, her research interests are in chemical profiling of illicit drugs as well as the extraction and detection of prohibited and controlled substances (including illicit drugs) from various matrices such as waste water, using mass spectrometric techniques. Drug abuse has contributed to detrimental social, health and economic implications in Southern Africa. Current research projects undertaken by the Forensic Chemistry Research Group at BIUST include chemical profiling of nyaope (a mixture of mainly heroin and cannabis) and methamphetamine (“Tik”) and waste water based epidemiology, targeting commonly used illicit drugs.

Aside from linking samples seized from different areas through their chemical profile, which in turn can be used to establish drug trafficking and distribution patterns, the research also aims to identify the cutting agents and adulterants used when making a mixture of nyaope. These are thought to include bicarbonate of soda, pool cleaner, teething powder, rat poison, lidocaine, acetaminophen, caffeine, methaqualone and antiretroviral drugs.

Waste water based epidemiology is based on detecting drugs of abuse in waste water with the aim of estimating community drug usage. This is in order to obtain near real-time information on the types and levels of drugs being used by communities in Botswana. The research projects, undertaken by masters and PhD students, are done in collaboration with the South African Police Service and Anglia Ruskin University (UK).

Related publications:

  • Mthembi, P.M., Mwenesongole, E.M., Cole, M.D., 2019. Chemical profiling of the street cocktail drug ‘nyaope’ in South Africa using GC–MS II: Stability studies of the cannabinoid, opiate and antiretroviral components during sample storage. Forensic Science International, 300, pp. 187–192.
  • Mthembi, P.M., Mwenesongole, E.M., Cole, M.D., 2018. Chemical profiling of the street cocktail drug ‘nyaope’ in South Africa using GC-MS I: Stability studies of components of ‘nyaope’ in organic solvents. Forensic Science International, 292, pp. 115-124.
  • Mwenesongole, E.M., Gautam, L., Hall, S.W., Waterhouse, J.W., Cole, M.D., 2013. Simultaneous detection of controlled substances in waste water. Analytical Methods, 5, pp. 3248-3254.

Pr. Haciba Rezk-kallah
Prof. Haciba Rezk-kallah

Algeria (M.Bitton from

Pharmacology – Toxicology Department, University Hospital of Oran

Pr. Haciba Rezk-kallah

Professor Haciba Rezk-kallah is the head of the Pharmacology – Toxicology Department at the University Hospital of Oran, and the director of the Environmental Health Research Laboratory of University of Oran 1. She is currently the president of the National Pedagogical Committee of Toxicology, vice-president of the National Pedagogical Committee of Pharmacy and the president of the Algerian Society of Toxicology (SATOX). After obtaining her pharmacy degree in 1985, she specialized in toxicology at Algiers University. At the Catholic University of Louvain (Brussels, Belgium), her research in industrial toxicology under Prof. Lauwerys focused on measuring blood and urinary phenyl acetic acid to assess occupational exposure of workers to manganese. She further obtained a PhD in medical sciences (Oran University) with research assessing the occupational exposure to chemical substances and ergotoxicological testing. Between 2000 and 2007, Pr Rezk-kallah was the head of the Pharmacy Department, Oran Faculty of Medicine. As the head of the Pharmacology – Toxicology Department at the University Hospital of Oran since 1996 she has developed clinical toxicology and management of chemical risk in the workplace. She currently aims to develop methods for forensic applications, including postmortem toxicological investigation, human-performance testing and forensic urine drug testing.

The Pharmacology – Toxicology Department is located in the University Hospital of Oran ( This city, nicknamed Oran the radiant (in Arabic Wahran El Bahia), is the second largest city in Algeria and an important Maghreb and Mediterranean metropolis. This coastal city has a temperate climate characterized by hot, dry summers and mild, wet winters.

The main mission of the Pharmacology – Toxicology Department is to perform clinical toxicology for the hospital, helping to diagnose, predict, manage and prevent intoxications due to drugs as well as environmental and occupational toxicants. The department comprises four units:

  1. Toxicological Emergencies and Toxicovigilance Unit, which handles an average of 600 requests each year. Benzodiazepines are the most commonly involved compounds in cases of voluntary or accidental intoxications. Pesticide poisoning comes in second, with almost 100 cases per year.
  2. Therapeutic Pharmacological Monitoring and Pharmacovigilance Unit, which particularly monitors immunosuppressants and antiepileptics.
  3. Professional and Environmental Toxicology Unit, which performs hundreds of analyses per year to assess the levels of metals exposure in workers of oil refineries, metal recovery companies, foundries, etc. They also assess levels of pesticides exposure in products production company workers and farmers.
  4. Drug Testing and Forensic Toxicology Unit, which handles on average 400 cases per year and is still being developed. Their work shows that cannabis is still the most widely used drug, and that the drug diversion phenomenon is gaining momentum. The unit has been participating to the UNODC International Collaborative Exercises (ICE) program since 2018.

In addition to the full time staff (chemists, biologists, laboratory technicians) and academic staff (hospital practitioners, assistant and full professors), the Pharmacology – Toxicology Department welcomes PhD candidates and directs research work of the Environmental Health Research Laboratory at the University of Oran 1. This “Industrial and Environmental Toxicology” team studies various topics:

  • Assessment and prevention of health risks linked to the use of pesticides at home and in the professional environment;
  • Addictive behaviors linked with psychoactive substances – screening, biotoxicological monitoring and prevention aspects amongst target and vulnerable populations;
  • Assessment of pesticides residue levels in water and food;
  • Biometrological monitoring of populations professionally exposed to metals, phytosanitary products for agricultural use and public health;
  • Assessment of phthalate exposure in the general population;
  • Chemical risk management in healthcare establishments;
  • Health risk assessments of energy drinks amongst youth;
  • Health risk assessments of passive smoking.

Related publications:

  • Chefirat, B., Boukalkha, H.H., Sadji, I., Rezk-kallah, H., 2015. Energy drinks: State of knowledge and consumption among young Algerians. Cahiers de Nutrition et de Diététique, 50, pp. 47–52.