Vol.:(0123456789) 1 3
Chemistry Africa
https://doi.org/10.1007/s42250-019-00079-6
REVIEW ARTICLE
Preliminary Review of Sources, Fate, Analytical Challenges
and Regulatory Status of Emerging Organic Contaminants in Aquatic
Environments in Selected African Countries
Nnanake‑Abasi O. Ofong
1,2,3
· Edu J. Inam
1,2
· John B. Edet
1,2
Received: 25 December 2018 / Accepted: 22 June 2019
© The Tunisian Chemical Society and Springer Nature Switzerland AG 2019
Abstract
Emerging contaminants (ECs) have received great attention in developed countries and as such some of them have received
priority screening and regulatory guidelines proposed. However, due to the requirements of highly sensitive and sophisticated
analytical equipment, research on this subject in developing countries in Africa are very scarce. We carried out a review
of published data from southern and western African region in order to: (1) highlight the environmental concentrations of
ECs in West and Southern Africa and bring to light the analytical challenges in order to elicit discussions on solutions, (2)
analyse the state of science regarding ECs in African environment and summarise available data for comparative analysis.
Generally, the study reveals that in spite of the scanty data reported, levels of ECs are in the upper range of global concentra-
tions. Monitoring data are increasing yearly, although at a very slow rate. Environmentally relevant levels reported are high
enough to cause potential risks. Priority monitoring of phenolic endocrine disrupting compounds, phthalate esters, triclosan,
triclocarban and some pharmaceutical active compounds (PhACs) like ibuprofen are recommended due to high frequency
of detection. Understudied compounds should be prioritized for toxicity studies, monitoring and potential risk evaluation in
order to increase knowledge on their sources and fate for proper management.
Keywords Emerging contaminants · Pharmaceuticals · Personal care products · Endocrine disrupting chemicals · Africa
1 Introduction
Emerging contaminants (ECs) consist of a group of organic
compounds recently suspected or known to cause adverse
ecological and/or human health efects [1]. The contami-
nants consist of an array of compounds including, but
not limited to, pharmaceuticals and personal care prod-
ucts (PPCPs), endocrine disrupting compounds (EDCs),
phthalates, perfluoroalkylated surfactants, perchlorate,
alkylphenolpolyethoxylates, etc. [2, 3]. The term “emerg-
ing contaminants” used to describe newly detected chemi-
cals in the environment is somewhat elusive since the term
“emerging” is a matter of perspective as well as timing [4,
5]. Furthermore, the term does not only pertain to the chemi-
cals themselves but also to the many dimensions associated
with their properties and their source-to-efect processes [6].
Therefore, a single list of these contaminants may not be
possible. At best, one would only consider and prioritize a
selected number for environmental monitoring or in general
discussions. Arp [7] considered emerging contaminants in
two groups, namely: “new” emerging contaminants, which
are chemicals that are recently manufactured and suddenly
become ubiquitous in the environment (e.g., decabromidi-
phenylethane) and “old” emerging contaminants, which are
the ones that actually had been around for several decades
but simply were not on the radar or for which analytical
methods were unavailable until recently (e.g., hexabro-
mobenzene). Some emerging contaminants are merely impu-
rities that are associated with chemical formulations [8, 9].
* Edu J. Inam
eduinam@uniuyo.edu.ng
Nnanake-Abasi O. Ofong
ofong18@mails.jlu.edu.cn
1
Department of Chemistry, University of Uyo, Uyo, Nigeria
2
Centre for Energy and Environmental Sustainability Research
(CEESR), University of Uyo, Uyo, Nigeria
3
Present Address: College of New Energy and Environment,
Jilin University, Changchun City 130021, Jilin Province,
People’s Republic of China