Heavy metals are known to be able to cross the placental and blood brain barriers to affect critical

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:

99% of all somatic and psychiatric hospital discharges, as well as outpatient visits from both private and public
all Swedish residents (http://www.socialstyrelsen.se/english). Over 99% of all somatic and psychiatric hospital
ues and y2 is the vector of censored values for any individual i. Similarly, partition the mean vector µ = (µ1 , µ2 )
Analogously to the interpretation of the Bayes factor in25, we provide similar interpretations of K in Table 1.
in µ and σ for each metal are given in Table 2. There is strong evidence that the mean and standard deviation of
of the elements in for each group. Table 3 shows that especially Pb tends to be associated with other metals.
Table 2. Probabilities and strength of evidence for the mean and standard deviation of the metal values in the
Metal values for 5‑year olds. Table 4 shows a strong evidence for higher average metal values of Hg in the
Table 3. Probabilities and strength of evidence for the pairwise correlations of metals being higher in one of
Table 4. Probabilities and strength of evidence for the mean and standard deviation of metal values for
Table 5. Probabilities and strength of evidence for the mean and standard deviation of the ratios RASD = (0)
Group comparison between metal values in the cord blood and for 5‑year olds. Table 5 shows
decisive evidence for the means and standard deviations of almost all metal values being higher in 5-year-olds.
mean p Ci = c1 |yi , y−i = 0.938, is actually the lowest average probability for all the 11 individuals in the figure.
meanp Ci = c1 |yi , y−i > 0.909 ⇔ at least strong favor to groupCj .
The remaining 49 individuals can not be classified according to this definition (Table 6).
viduals were correctly classified with at least decisive favor to one of the groups, see Table 7.
individual with such a value to belong to either group. Table 8 shows the values of the marked thresholds in Fig. 9.
This complements the previous classification results in Tables 6 and 7, where the whole vector of metal values
Table 6. Confusion matrix for the classified 11 individuals with at least strong favor to one of the groups.
Table 7. Confusion matrix for the classified 5 individuals with at least decisive favor to one of the groups.
conditional on the posterior draws of µ and . The 1% most extreme metal values are not shown for each metal
Table 8. Threshold values for strong and decisive evidence of a metal value x belonging to the ASD (in bold)
1. Frazier, T. W. et al. A twin study of heritable and shared environmental contributions to autism. J. Autism Dev. Disord. 44(8),

Methods (brief)

between individuals with or without (controls) autism spectrum disorder (ASD) diagnosis. The samples
then in the serum of these children at 5 years of age. We compared samples from children with ASD diagnosis
to samples from children without ASD diagnosis (controls) to identify whether some of these metals could be of
relevance for ASD etiology. The study employed samples from a biobank related to the All Babies in South Sweden
Origin of samples. The samples are part of the biobank associated to the ABIS (All Babies in Southeast
Sweden) registry. The samples are stored at the Division of Pediatrics of the Department of Biomedical and
was collected at birth, while blood, urine, stool, and hair were obtained from children at the ages of 1, 3 and
Database employed for diagnosis. The categorization of the samples as coming from children with
Analysis of metal levels. The samples were analyzed for the concentration of aluminum (Al), cadmium
(Cd), mercury (Hg), lithium (Li), lead (Pb) and zinc (Zn). For cord blood, 20 samples were randomly selected
dren, 11 samples were analyzed from ASD diagnosed children and 24 from the control group. The analysis of
plasma sector field mass spectrometry method’ (ICP-SFMS)17 after acid digestion with HNO3, according to the
samples suggests that the ASD population is exposed to less nutritional options providing Zn as a micronutrient
only based on our dataset, a similar approach can be employed in future studies that incorporate a larger sample
snow samples by inductively coupled plasma sector field mass spectrometry. Anal. Chim. Acta 450(1), 193–205 (2001).
1. ISO-17294-1:2004. Water quality—Application of inductively coupled plasma mass spectrometry (ICP-MS)—Part 1: General
1. ISO-17294-2:2016. Water quality—Application of inductively coupled plasma mass spectrometry (ICP-MS)—Part 2: Determina-
1. EPA-Method-200.8. Determination of trace elements in waters and wastes by inductively coupled plasma-mass spectrometry

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

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.

Commit	Date	Change	Description
b01ec52c	2026-08-04	major	2 sections added
d49e450f	2026-08-03	major	5 sections added; narrative text revised