Heavy metals in dry depositions as indices of atmospheric pollution in Enugu

Overview

This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.

Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

• concentrations (mg/kg) as follows; Cu – 146.29 ± 10.23 , Cr – 13.01
• Pb – 0.43 ± 0.09 , Cd – 2.43 ± 0.21 . The mean values of the
• 0.1% of dry plant tissue and are used in relatively categorized as industrial, commercial, residential
• elevation of 3 meters above the ground covered and acceptable permissible limit of the same metal
• values of 25, 25, 20, 30, 123, 10 and 6mg/kg
• Table 1. The mean values of the metals concentrations in the sampling locations
• was recorded in Achalla Layout, which is high (25.9±10.1 ppm) in Maiduguri area and within the
• density populated area. This high values may be as range of values of this study (122.0±48.0 ppm) in
• al. 2013). 1988).There is about 8% increase in the levels of
• values in the range of 0.73 ± 0.15 to 13.01 ± 0.30 being the result of combustion of gasoline
• (mg/kg). The highest value of 13.01 ±0.30 (mg/kg) containing MMT (Loragner and Zayed 1995).
• industries, commercial and residential fuel from 86.17±2.14 to 507.24 ±2.97 (mg/kg) which is
• (Kimbrough et al. 1999; Pacyna and Pacyna 2001). (318.0 ± 38.0 ppm) and Yola (139.0 ± 53.0 ppm)
• very essential in the metabolism of glucose, fat and concentration of 507.24 ± 2.97 mg/kg was
• high concentration of Chromium (54.28 mg/kg) environment and the use of zinc in brass, bronze,
• mean values of concentration in the ranges of 6.72 potential release of zinc into the environment
• ± 0.44 to 30.35 ± 0.37 (mg/kg). This value is higher through various waste streams (ATSDR 1995). Zinc
• than the earlier recorded value (0.1 – 0.8 mg/kg) by is essential to all life forms and it is used as a dietary
• humans of the carcinogenicity of compounds of 0.32 ± 0.03 to 0.43 ± 0.09 (mg/kg), which is very low
• Manganese showed a mean value in studies by (Ogugbuaja and Barsisa 2001; Ekere and
• concentration in the range of 82.10 ± 1.53 to 179.07 Ukoha 2013; Bilos et al. 2001), (97.5±5.8 ppm) and
• ± 0.82 (mg/kg) which is lower in the value recorded (81.8 ± 5.3 ppm); (4.8 ± 0.0 - 87.0 ± 0.1 mg/kg);
• ppm) (Ogugbuaja and Barsisa, 2001). Manganese is atmosphere is from the combustion of waste
• is about 0.1% of the earth crust (Gradel, 1978). This lubricants. Lead also enters the air through the
• cadmium ranged from 0.59 ± 0.18 to 2.43 ± 0.21 of the use of fertilizers, pesticides and herbicides.
• environment. It is not degradable in nature and can The table 2 below shows the values of
• linked to lung and prostate cancer. The Then the table 3 shows the values of potential
• compared with the results of other studies around tables 2 and 3 has a mean range as follows: degree
• of the environmental conditions of the area and mean value in the range of 418.68 – 919.90.
• study, human error and assessment. al. (2017) the mean values are 0.13; 809; 366.42,
• Table 2. Contamination factors (Cf), degree of contamination (Cd), modified degree of contamination (mCd) and
• Table 3. Potential ecological risk factors and potential ecological risk indexes (RI) of heavy metals in dust samples
• mean values of PLI during the study period across 2017). Achalla Layout is shown to have the highest
• Fig. 2. The bar chart showing the mean values of PLI during the study period across the locations
• Fig.3 .The bar chart showing the mean values of RI during the study period across the locations
• ecological risk 37%
• Physical Sciences, 8 (4):175-178. Loranger S, Zayed J (1995) Contribution of

Methods (brief)

• Dry Deposition deposition in Enugu Urban, Nigeria. Dry deposition samples are
• Bio-accumulation collected using plastic containers mounted on elevation of 3 meters
• Ecological risk for 30 days. The dust samples were collected for 3 consecutive
• composite samples were collected for analysis. The samples were
• (ICP – OES). The result shows the highest mean values of the metals
• Dry deposition samples were collected The first step in determining the degree of
• The samples were collected after 30 days
• The dust collected within the period were
• transferred into sample bottles and taken to
• laboratory for analysis. A 1.0g of the dust sample
• To the 5ml of digested sample, 10ml of It is important to note that the
• distilled water. The samples were analyzed using Cif ≥ 6 respectively while degree of contamination
• Plasma – Optical Emitting Spectrometer (ICP – OES). considerable and very high when the values
• bioaccumulate (WHO 1992a). obtained from the dust collected at various location
• pollution load index (PLI) of heavy metals in dust samples collected at different periods
• Table 3. Potential ecological risk factors and potential ecological risk indexes (RI) of heavy metals in dust samples
• From the 27 samples collected from the 9 locations classifying the pollution degree as below:-
• Low ecological risk - 0 sample

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Shellfish (shrimp, crab, lobster, clams, oysters, mussels)
• Mercury
• Cadmium
• Arsenic
• Nickel
• Chromium

Verification notes

• Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
• Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
• Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
• Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
• HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.