Assessment of DDT, HCH and PAH contamination and associated ecotoxicological risks in surface sediments of coastal Tema Harbour (Ghana)

A case study of 38 micro‐organic pollutants contamination in Kirmir Stream, Turkey

“…Other diagnostic characters of contribution to the PAHs contamination of water and sediment have been used to determine their sources either petrogenic (crude oil, petroleum spills, etc.) and pyrogenic (vegetation fires or fossil fuel combustion) sources (Bandowe et al., 2014; Botwe et al., 2017). To characterize the dominant source of PAHs contamination in water and sediments, six of such ratios were used in this study (Exhibit 5).…”

The state of POPs in Ghana- A review on persistent organic pollutants: Environmental and human exposure

“…Provided the ratio of DDT to its metabolites is <1, past usage is predicted. Calculated ratios observed were <1 for river, lake and coastal sediments (Afful et al, 2013b;Botwe et al, 2017;Darko et al, 2008b;Ntow, 2005), indicating a decline in DDT usage with an increase of its metabolites over the years.…”

“…DDTs and HCHs were frequently detected in surface sediments covering coastal Tema harbour areas, Weija dam and Nsawam (Densu river basin) in Greater Accra, Eastern region, Lake Bosomtwe and 4 streams in Ashanti region, Volta lake (6 sites), and Tono irrigation reservoir in the Northern region. The sum of DDTs were highest for irrigation sediment (47-70 µg kg -1 dw) (Akoto et al, 2016), followed by Volta Lake (61.30 µg kg -1 dw) (Ntow, 2005), coastal sediments (6.0-12.8 µg kg -1 dw) (Botwe et al, 2017), lake sediments (LOD-12.75 µg kg -1 dw) (Afful et al, 2013b;Darko et al, 2008b), river basin sediments (3.289 µg kg -1 dw) (Kuranchie-Mensah et al, 2012), and streambed sediments (0.46 µg kg -1 dw) (Ntow, 2001). Mean HCHs (0.75-13.6 µg kg -1 dw) were much lower.…”

Sediments in the Tema Harbour (Ghana): chemical pollution and sedimentation rates

“…This is also the case for the tropical marine Tema Harbour in Greater Accra (Ghana). Anthropogenic activities are a source of a wide range of hazardous substances, which adversely impact organisms inhabiting the coastal marine environment : previous studies have shown that sediments of the Tema Harbour are contaminated by polycyclic aromatic hydrocarbons and organochlorine pesticide residues (Botwe et al, 2017) and metals Botwe et al, unpublished results). Since Tema Harbour sediments are dredged periodically with subsequent disposal/storage under seawater, assessment of sediment quality is required to guide sediment management decisions at Tema…”

“…The metal concentrations were measured using ICP-MS (Varian, Australia). The dry sediments were also analysed for their grain-size distribution by the Malvern laser diffraction method (Blott et al, 2004), while total organic carbon (TOC) was analysed by the Walkey-Black wet oxidation method following Botwe et al (2017). The mean metal recoveries in the standard BCR-701 samples ranged between 77…”