DETERMINATION OF SOME HEAVY METALS IN FISH AND LIVESTOCK FEEDS, MANURE AND RIVERS IN SELECTED STATES IN NORTHERN NIGERIA

  • Ms Word Format
  • 77 Pages
  • ₦3000
  • 1-5 Chapters

DETERMINATION OF SOME HEAVY METALS IN FISH AND LIVESTOCK FEEDS, MANURE AND RIVERS IN SELECTED STATES IN NORTHERN NIGERIA

Abstract:

The increasing levels of environmental pollution by toxic metals from various sources have generated a great concern on their impact on human health. Rapid developments, increase in mining activities, farming, insurgency, industrial activities and waste disposals have gradually redistributed many of the toxic metals from the earth crust to the environment, raising the chances of exposure through ingestion, inhalation or skin contact. This study is aimed at determining the concentrations of zinc, copper, nickel, lead and arsenic metals in four compound fish feeds [FA, FB, FC and FD] poultry feeds [PA, PB, PC and PD] , forage grasses; animal manure and major rivers (Kaduna, Sokoto and Ngadda) obtained in northern Nigeria. Brands of compound fish and poultry feed samples were collected from five different distributors of the feeds. Forage grass and manure samples from five different grazing pasture stations in north central, north western and north eastern zones of Nigeria were collected. Water samples were also collected from the rivers Kaduna, Sokoto and Ngadda. The samples were digested with concentrated nitric acid (HNO3), concentrated sulphuric acid (H2SO4) and perchloric acid (HCIO4) in the ratio 1:2:1 (Uba et al.., 2000). The Percentage recovery of the metals using the analytical method adopted gave range of 92.07 to 101.02% for feeds and 92.22 to 103.13% for manure was determined for the heavy metals by atomic absorption spectrophometry. The results obtained expressed in mg/kg for livestock feeds showed mean concentration ranges between 5.10 ± 0.04 – 6.38 ± 1.50 mg/kg for zinc as the highest concentrated heavy metal, followed by 3.06 ± 1.08 mg/kg – 3.16 ± 1.65 mg/kg for copper, then 0.14 ± 0.08 – 0.38 ± 0.25 mg/kg for lead, 0.10 ± 0.44 – 0.19 ± 0.07 mg/kg for nickel, and 0.01 ± 0.02 – 0.05 ± 0.04 mg/kg for arsenic as the lowest concentrated metal in the compound fish feeds. For compound poultry feeds, the same trend as in fish feeds was observed with a concentration range of 5.06 ± 1.67 – 8.45 ± 1.91 mg/kg for zinc, 3.00 ± 3.06 – 35 ± 1.08 mg/kg for copper, 0.72 ±0. 81 – 1.41 ± 0.08 mg/kg for lead 0.04 ± 0.02z – 0.10 ± 0.06 mg/kg for nickel and non detection – 0.03 ± 0.01 mg/kg for arsenic. FA and PB feed brands contained higher concentrations of the essential metals than the other brands sampled. The levels of the metals in the feeds were below the permissible limit stipulated by European Union. The mean concentrations of these metals in forage grasses being grazed by cattle in northern Nigeria had highest zinc and copper levels (7.00 ± 2.04 mg/kg and 6.61 ± 0.82 mg/kg) respectively and highest arsenic concentration (0.33 ± 0.06 mg/kg) was obtained in Kagara areas while highest nickel level (0.83 ± 0 .56 mg/kg) was obtained in Zungeru area, all in North central zone. The levels were below the permissible limit (100 mg/kg) stipulated by European Union. The mean lead value 6.53 ± 0.51 mg/kg and 5.82 ± 0.63 mg/kg were obtained in Anka area, North west and Zungeru, North central Nigeria respectively and were above 5mg/kg stipulated by European Union for lead in feeds. The trend of the metal levels in poultry and cattle manures were Zn > Cu > Ni > Pb > As and Pb > Zn > Cu > Ni > As respectively. The highest mean concentration 4.15 ± 2.64mg/kg was obtained in poultry manure related to zinc in North central while highest mean concentration 3.22 ± 0.01mg/kg in cattle manure is related to lead in Anka area in North western Nigeria. The feeds are relatively safe for aquaculture and livestock production. However, the forage grasses are relatively not safe for grazing by animals due to high lead levels. The high lead values in water samples indicate that Northern Nigerian environment is critically contaminated with respect to this toxic metal and thus pose serious environmental concern and may pose as risk to public health.

DETERMINATION OF SOME HEAVY METALS IN FISH AND LIVESTOCK FEEDS, MANURE AND RIVERS IN SELECTED STATES IN NORTHERN NIGERIA

0 Shares:
Leave a Reply

Your email address will not be published. Required fields are marked *

You May Also Like