Occurrence of organochlorine pesticide residues in biological and environmental matrices in Africa: A two-decade review

Chijioke Olisah; Omobola O Okoh; Anthony I Okoh

doi:10.1016/j.heliyon.2020.e03518

Occurrence of organochlorine pesticide residues in biological and environmental matrices in Africa: A two-decade review

Heliyon. 2020 Mar 3;6(3):e03518. doi: 10.1016/j.heliyon.2020.e03518. eCollection 2020 Mar.

Authors

Chijioke Olisah^{1

2

3}, Omobola O Okoh^{1

2

3}, Anthony I Okoh^{2

3}

Affiliations

¹ Department of Pure and Applied Chemistry, University of Fort Hare, Alice 5700, South Africa.
² Applied and Environmental Microbiology Research Group (AEMREG), Alice 5700, South Africa.
³ SAMRC, Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa.

Abstract

The widespread use of organochlorine pesticides (OCPs), essentially for the control of insects and the cultivation of food crops, has led to the pollution of ecosystems. Despite being banned several years ago in the developed world, extensive use remains ongoing on the African continent. This review summarizes the occurrence, distributions, sources, and trends of OCPs in seven environmental matrices (atmosphere, water, sediments, soils, biota, human fluids and food products) in Africa. Findings in this review revealed that α-HCH, β-HCH dichlorodiphenyltrichloroethane (DDTs), and endosulfans were the most persistent OCP residues in the African environment, particularly DDTs in breast milk samples occurring in levels above the WHO stipulated limits, thus indicating a call for concern. Also, there was paucity of data available on OCP concentrations in ambient air. Future research efforts should prioritize testing these pollutants in the atmosphere, especially in countries where they are used more frequently. While most POP analysis studies used gas chromatography coupled to electron capture detector or mass spectrometer, it is recommended that further studies should use more sensitive analytical techniques such as gas chromatography with tandem mass spectrometry (GC-MS/MS), or gas chromatography coupled to high-resolution mass spectrometry (GC-HRMS). These instruments allow for the detection of secondary and tertiary metabolites, especially those found in water, biota and food products, which are critical vectors of OCPs to human and animal bodies. Training of farmers and other domestic users on the handling of pesticides is proposed.

Keywords: Africa; Analytical chemistry; Earth sciences; Ecosystem; Environment; Environmental science; Gas chromatograph; Occurrences; Occurrences. pollutants; Organic chemistry; Pollutants; Toxicology.

Publication types

Review