Essential, trace and toxic elements content, their

Overview

This source page is a mechanical bulk-ingest record for a PDF in the methylmercury infant-formula research pull. 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:

License:   This work is licensed under a Creative Commons Attribution 4.0 International License.
surface water sampling was conducted from June 2021 to June 2022 at selected points and analyzed for
22 elements (Al, As, Cu, Cr, Mn, Zn, Ni, Cd, Pb, B, Ba, Co, Na, Se, Ag, Be, Mg, K, Bi, Li, Sr, V). The annual
average concentrations of Al and Mn where found at the five monitoring points were 27.5 ± 8.0 µg L–1
and 89.7 ± 40.1 µg L–1, respectively, categorize these metals as major pollutants. Exceedances above the
permissible concentrations of Ni (5.2 ± 1.3 µg L–1), Cd (0.30 ± 0.08 µg L–1) and Pb (3.0 ± 0.5 µg L–1) were
2022). Major contributors to increasing cadmium levels in the environment include mining, the production
application of chemical fertilizers in agriculture, and industries using Cd dyes (Pan et al. 2010). Effluents
(Tumolo et al. 2020). Water purification using aluminium salts as coagulants increase its content in
natural waters (Krupinska 2020). The presence of manganese, zinc, copper up to certain amounts in
observed when road runoff via stormwater is introduced into aquatic ecosystems (Müller et al. 2020). The
ceramics, cosmetics and fireworks. (Khosravi-Darani et al. 2022). All of the following toxic elements
and lung cancer, while chronic exposure to As can lead to peripheral vascular disease (Qiao et al. 2020).
tumor and v) Al have been found in Alzheimer’s patients (Krupinska 2020; Mehdi et al. 2021; Qiao et al.
2020; Tchounwou et al. 2012). According to the International Agency for Research on Cancer IARC (IARC
2016), the following heavy metals are categorized as carcinogens into next groups: 1 – As, Cd, Cr, Ni and
human health (Kang et al. 2020). Besides lead and manganese, the concentrations of Ba, Cd, Co, Cr, Cu,
Ni, V, Zn are affected as a result of traffic (Müller et al. 2020) Lithium is an essential element in many
formation and development of blood cells (Aral and Vecchio-Sadus 2008). Natural sources of beryllium
Prolonged consumption of drinking water containing more than 4 µg Be/l has been shown to have
adverse effects on the skin and lungs, as well as damage to the skeletal system (Bolan et al. 2023).
and landfill leachates (Hasenmueller and Criss 2013). Boron is extremely beneficial for plant growth, has
maintained in organisms at higher levels (Nielsen 2014). The content of Se, Sr, Ag in river waters is
muscle cramps – Mg, pernicious anemia – Co, etc. (Zoroddu et al. 2019). It is of utmost importance to
2022). In the food chain and through drinking water, these levels have an impact on human health.
Martin, 2002; Konovalov and Murray, 2001; Simionov et al., 2021; Theodosi et al., 2013). Guieu et. al.
(Guieu and Martin 2002) studied the concentrations of dissolved trace metals as Al, Cd, Cu, Fe, Co, Mn, Pb
Cu in comparison with other large rivers in the region. Simionov et. al. (Simionov et al. 2021) determined
Black Sea. The average contents of the studied metals were found between 0.5 to 57 µg Zn L–1; 0.1 to 1.5
µg Fe L–1; 0.5 to 6.7 µg Cu L–1; 1.0 to 8.5 µg Ni L–1; 0.4 to 3.9 µg As L–1; 0.5 to 3.1 µg Pb L–1; 0.004 to
0.14 µg Cd L–1; 5.5 to 8.1 mg Mg L–1; 2 to 30 mg K L–1; 17 to 44 mg Na L–1; 45 to 64 mg Ca L–1. The
the sediment and a higher Pb content in the parasites were found (Kirin 2014).
The Karaagach River is located in Southeastern Bulgaria, near the town of Kiten, with a length of 30.5
and Burgas Lake Vaya in Southeastern Bulgarian Black Sea region (Falah et al. 2019; Kirin 2014).
Ridge, 331 m above sea level, about 400 m northeast of Demira peak (424 m). Almost along its entire
In selecting sampling points along the river, several requirements were taken into account: 1) its location
is in a protected area and a point with low anthropogenic influence is needed; 2) in order to reflect the
agricultural areas should be selected; 3) a point located next to a sewage discharge should be selected; 4)
Point 1 is furthest from built-up areas, urban territories and agricultural activities development. Near point
2 there are pastures for livestock and cultivated agricultural areas. Cereals such as maize and wheat are
from June 2021 to June 2022. Their transport to the laboratory was carried out at 4°C using polyethylene
prepared in triplicate. They were analyzed for the content of 22 essential, trace and toxic elements by ICP

Methods (brief)

the concentrations of Zn, Fe, Cu, Ni, As, Pb, Cd, Mg, K, Na, Ca in water samples from the Danube River and
The surface layer water samples of the Karaagach River were sampled monthly from the indicated points
bottles pre-treated with dilute ultrapure nitric acid, washed with deionized water and dried. The samples
prepared in triplicate. They were analyzed for the content of 22 essential, trace and toxic elements by ICP
of the tested elements were calculated and their limits of detection LODs and limits of quantification
LOQs were determined as presented in Table 2.
Elements Analytical yield (%)* LOD LOQ MAC** AAC**
relationships between pairs of analytes in the samples and provide information on their origin. MS Excel
< LOQ, B – 13.37 ± 1.40 µg L–1, Na – 9.49 ± 0.95 mg L–1, Mg − 12.89 ± 0.69 mg L–1, K – 3.76 ± 0.18 mg L–
anthropogenic contamination, as in the other months their levels are below or around their LOQs. It is
Pearson’s coefficient. High Pb and Ni amounts in water samples were recorded during the summer
Sample point HEI Cf,Al Cf,Mn Cf, Pb Cf,Ni Cf,Cd Cd
spectrometry (ICP-MS) - Part 2: Determination of selected elements including uranium isotopes.
1. Zoroddu, M. A., Aaseth, J., Crisponi, G., Medici, S., Peana, M., & Nurchi, V. M. (2019). The essential

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.

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Verification notes

Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
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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.

Commit	Date	Change	Description
3171d06	2026-08-02	major	1 section added
bc84bfc	2026-08-02	major	6 sections added; narrative text revised