ABSTRACT
Theconcentrations of lead, nickel, silver, zinc, chromium, copper, vanadium, cobalt, and
cadmium were determined in plastic housing of waste television sets produced in some years of
1980’s, 1990’s and 2000’s, and in plastics of waste mobile phones produced in some years of
1990’s and 2000’s, the samples were collected mainly from mobile phone and television
repairers at railway in Ogbete main market, Enugu in Enugu state, and the famous computer
village inIkeja, Lagos State Nigeria, with the aim of providing information on the trend in
concentration of these metals within the years. The concentrations of these nineelements were
determined by flame atomic absorption spectrometry after acid digestion using a 1:1 mixture of
sulphuric and nitric acid. The mean concentration of these metals (mg/kg) in the television set for
the 1980’s, 1990’s and 2000’s respectively are (12.76±17.61, ND, 1.33±2.30) for lead;
(1.84±1.33, 1.48±1.26, 2.79±2.47) for nickel; (1.53±2.35, 16.20±29.66, 40.42±20.49) for silver;
(82.24±50.59, 159.69±55.87, 113.29±69.175) for zinc; (7.12±10.50, 4.23±1.07, 5.26±4.73) for
chromium; (3.26±1.09, 2.76±1.15, 2.39±1.05) for copper; (4.84±10.83, 24.05±7.56,
26.67±11.13) for vanadium; (9.30±5.27, 8.40±3.00, 12.63±12.99) for cobalt; (2.60±1.25,
4.05±1.81, 4.28±1.11) for cadmium (ND - Not Detected). The mean concentration of these
metals (mg/kg) in the mobile phones are (50.83±65.85, 5.71±3.55) for lead; (23.80±27.89,
1.95±1.28) for nickel; (48.04±89.00, 7.82±4.61) for silver; (325.11±261.50, 105.59±26.72) for
zinc; (5.47±3.97, 4.38±3.93) for chromium; (643.92±880.48, 47.51±97.06) for copper;
(20.94±5.59, 34.50±25.61) for vanadium; (4.92±1.55, 13.21±8.16) for cobalt; (8.14±7.06,
17.60±19.14) for cadmium.The total threshold limit concentration of these metals are; lead-
1000, nickel- 2000, silver 500, zinc- 5000, chromium- 2500, copper-2500, vanadium-2400,
cobalt-8000, cadmium-100 (mg/kg) (sourced from California Code of Regulations). Although
the mean concentration values of Zn, Cu and Ag in both the mobile phones and television
samples were relatively high compared to the total threshold limit concentration (TTLC), all the
metal concentration values were below the threshold limit except for Ag. Two results exceeded
the TTLC threshold for Ag (500 mg/kg) within phone samples (1990). These results suggest that
there may not be any immediate danger from waste television and mobile phone plastic housing
investigated.
GRACE, O (2021). Determination Of Heavy Metals In Plastic Housing Of Selected Obsolete Mobile Phones And Television Produced In Some Years Between 1980 And 2000. Afribary. Retrieved from https://tracking.afribary.com/works/determination-of-heavy-metals-in-plastic-housing-of-selected-obsolete-mobile-phones-and-television-produced-in-some-years-between-1980-and-2000
GRACE, OKENWA-ANI "Determination Of Heavy Metals In Plastic Housing Of Selected Obsolete Mobile Phones And Television Produced In Some Years Between 1980 And 2000" Afribary. Afribary, 13 May. 2021, https://tracking.afribary.com/works/determination-of-heavy-metals-in-plastic-housing-of-selected-obsolete-mobile-phones-and-television-produced-in-some-years-between-1980-and-2000. Accessed 10 Nov. 2024.
GRACE, OKENWA-ANI . "Determination Of Heavy Metals In Plastic Housing Of Selected Obsolete Mobile Phones And Television Produced In Some Years Between 1980 And 2000". Afribary, Afribary, 13 May. 2021. Web. 10 Nov. 2024. < https://tracking.afribary.com/works/determination-of-heavy-metals-in-plastic-housing-of-selected-obsolete-mobile-phones-and-television-produced-in-some-years-between-1980-and-2000 >.
GRACE, OKENWA-ANI . "Determination Of Heavy Metals In Plastic Housing Of Selected Obsolete Mobile Phones And Television Produced In Some Years Between 1980 And 2000" Afribary (2021). Accessed November 10, 2024. https://tracking.afribary.com/works/determination-of-heavy-metals-in-plastic-housing-of-selected-obsolete-mobile-phones-and-television-produced-in-some-years-between-1980-and-2000