mycotoxins and heavy metals in rice, maize,

Overview

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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:

A total of 300 samples consisting of rice (n = 82), maize (n = 50), soybeans (n = 78), and
vortexed for 5 min. Then, 8.4 mL of ACN containing 1% HCOOH was added, and the
the digestion was as shown in Table S1. After the digestion, the temperature was reduced to
with 0.1% HCOOH to detect three FBs and 5 mmol/L CH3COONH4 in H2O for the remaining
mycotoxins. The gradient elution program was as follows: 0-3 min, 10% A; 3-5 min, 70%-
90% A; 5-6 min, 90% A; 6-6.1 min, 90%-10% A; and 6.1-8 min, 10% A. The flow rate was
high-purity nitrogen (99.99%). The collision gas was high-purity argon, and the capillary
parameters are detailed in Table S2. Heavy metal analysis was performed on an ICAP RQ
Alimentarius Commission (CAC), the European Union, and the U.S. were used. Table S3
between mean values using SPSS 16.0 (SPSS Inc., IL, USA), with P<0.05 indicating
LOD, it was considered as “not detected” and replaced by 1/2 LOD when calculating the
mean value of the contaminants (38).
The LOD and LOQ values for the developed method are shown in Table S4. As for
the slope ratio ranged from 0.31 to 3.6 (Table S5), demonstrating a matrix effect. Therefore,
all standard curves). The LODs ranged from 0.05 to 4.0 μg/kg for the 12 mycotoxins
0.8% and 9.7%, respectively. For ICP-MS analysis, the LODs ranged from 0.001 to 0.02
mg/kg, and the R2 prepared with standard solutions for Pb, Cd, Cr, As, and Hg were ≥ 0.994.
and 9.5%, respectively. All the contaminations of spiked recovery rate were between
80~120%, and the RSDr and RSDR were all < 10%.
(72.33%) was the highest, followed by OTA (59.33%), 3-ADON (39.00%), and FB3
for each), FB2 (19.67%), ZEN (18.00%), and AFG2 (6.33%). For heavy metals, As had the
highest detection rate (91.33%), while for Cd, Cr, and Pb, the contamination rates were
85.00%, 39.00%, and 18.67%, respectively. Hg minimally contaminated the samples, as
detected in only 2 (0.67%) samples. Within the rice samples (n = 82), OTA was the most
common detected mycotoxin (73.17%), followed by DON (48.78%), and the remaining
metals analyzed, As had the highest detection rate (100.00 %) in rice. The detection rates for
the other heavy metals were as follows: Cd at 90.24%, Cr at 26.83%, Pb at 12.20%, and Hg at
1.22% (Figure 2B). For maize samples (n = 50), FB1 (98.00%) was the most detected
mycotoxin, followed by DON and FB2 (80.00% for each), OTA (68.00%), and the remaining
mycotoxin detection rates ranged from 4.00% to 58.00%, while 15-ADON was not detected.
On the other hand, As had the highest detection rate (88.00%), and the rest were in the order
of Cd (30.00%), Pb (10.00%), and Cr (6.00%), while Hg was not detected (Figure 2C). In
OTA, which was detected in 66.67% of the samples. Other mycotoxins were detected in a
range between 1.28% to 46.15%. The detection rate of Cd among the five heavy metals was
the highest (98.72%), and the remaining were in the order of Cr > As > Pb > Hg, with
wheat flour samples (n = 90), DON was at the highest detected rate of all mycotoxins
(86.67%), while the remaining mycotoxins were detected in a range between 3.33% and
35.56%. Among the heavy metals, Cd was found at the highest rate of 98.89%, and the rest
was in the order of As > Pb > Cr, with detection rates of 83.33%, 26.67%, and 21.11%,
detection rates of 98.00% and 80.00%, respectively. ZEN had an overall low detection rate
but was more frequently found in rice samples at a detection rate of 34.15%. OTA was
frequently in wheat flour (35.56%). Furthermore, the highest detection rate for Cr was found

Methods (brief)

chromatography-tandem mass spectrometry (UPLC-MS/MS) and inductively coupled plasma
mass spectrometry (ICP-MS) methods to quantify the concentration of 12 mycotoxins and
five heavy metals in rice, maize, soybeans, and wheat flour samples marketed in Shanghai.
samples (100%) were contaminated with two or more contaminants, and 77.3% of the
samples were co-contaminated with more than four contaminants. In cereals and cereal
tandem mass spectrometry (UPLC-MS/MS) and inductively coupled plasma mass
spectrometry (ICP-MS) to analyze four typical grains and grain products (rice, maize,
had a purity > 98%. The high-purity solvents (HPLC grade) of methanol (MeOH),
(Waters, MA, USA) was used for the UPLC-MS/MS analysis. An ICP-MS spectrometer
Sample digestion was conducted using a MARS6 microwave digestion system (CEM, NC,
Instrument (Troody Analytical Instrument Co., Ltd, Shanghai, China). The sample solution
China) was used for supersonic-assisted extraction. Samples were weighed on an AL104
2.2 Sample collection and extraction
A total of 300 samples consisting of rice (n = 82), maize (n = 50), soybeans (n = 78), and
wheat flour (n = 90) were collected from over 100 supermarkets and farmers’ markets located
(the map was drawn using Adobe Photoshop CC-Adobe Inc, USA, CA). The collected
samples can be traced back to 232 manufacturers and 219 sample origins. To ensure sample
representativeness, various samples of the same batch were randomly selected at each site.

Implications

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Verification notes

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