Platycladi semen, known as “Bai Zi Ren” in Chinese, refers to the dried ripe seed kernel of the plant Platycladus orientalis (L.) Franco. It has been widely used in China for over 2000 years due to its high medicinal and edible values. The seed contains several chemical compounds, such as oleaginous components, polysaccharides, saponins, and amino acids, which have multiple pharmacological functions including anti-oxidation [1], anti-inflammation [2,3], and anti-cancer [4]. As a traditional Chinese medicine (TCM), Platycladi semen is commonly utilized to treat palpitations, soothe the five organs, invigorate the qi, expel dampness and relieve paralysis [5]. Additionally, it is a highly valuable food and medicinal source, providing nutrients and medicinal components that are often lacking in other cereal types, and it can be used as an edible foodstuff to make soups, porridge, as well as tea drinks.

As a substance with dual function in TCM and food, Platycladi semen has demonstrated remarkable adaptability in both medicinal and culinary applications. Unfortunately, it is highly susceptible to contamination by multiple fungi, such as Aspergillus, Fusarium and Penicillium, which can produce a variety of mycotoxins [6]. Consuming Platycladi semen contaminated with mycotoxins can lead to serious health problems, including immunosuppression, carcinogenicity, genotoxicity, hepatotoxicity, nephrotoxicity, and reproductive disorders [7,8]. Mycotoxin contamination is likely to take place at various stages, including growth, harvest, transportation, and storage [9]. Since these mycotoxins are highly stable at high temperatures, it is not feasible to completely reduce or eliminate them through food processing or roasting. Moreover, they can migrate into food and related products [10]. Mycotoxin contamination has emerged as a significant global public health concern, endangering human and animal well-being and exerting negative impacts on the global economy and international trade. To guarantee product safety and minimize economic losses due to mycotoxin contamination, it is essential to establish a sensitive, reliable, and accurate method for efficiently determining various mycotoxins in Platycladi semen. In recent decades, chromatographic techniques [[11], [12], [13], [14], [15]] have been widely accepted and have become the mainstream strategy for addressing this issue. Among these techniques, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with multiple reaction monitoring (MRM) mode is the ideal choice for detecting multi-mycotoxins due to its remarkable separation capabilities, rapid analysis, high sensitivity and selectivity [16]. Before UPLC-MS/MS analysis, the sample pretreatment method is crucial for the efficient extraction of mycotoxins from complex matrices. QuEChERS (quick, easy, cheap, effective, rugged, and safe), a rapid, cost-effective, highly efficient technique, has gained increasing global attention for detecting mycotoxins in diverse complex matrices [[17], [18], [19], [20]], especially TCMs [15,16,21]. Therefore, after some modifications, the QuEChERS technique was employed for the highly efficient extraction of mycotoxins in Platycladi semen samples.

Given the toxicity and high contamination levels of mycotoxins, it is urgently necessary to conduct health risk assessments for human exposure to these mycotoxins via the daily consumption of foods or TCM. Medicinal foods, especially those rich in oil and highly valued for their edible qualities, can provide nutrition that fosters fungal growth, making them particularly susceptible to contamination by various mycotoxins, thereby presenting a potential threat to human health. Monte Carlo simulation (MCS), an outstanding statistical instrument for scrutinizing variability and uncertainty in risk assessment, has gained attention and is widely used to evaluate health risks [22,23]. Generally, dietary exposure risk assessment methods are mainly divided into deterministic exposure assessment models and probabilistic exposure assessment models. The former represents a method that uses specific and definite values to evaluate the potential exposure risk, it is suitable for screening chemicals but has the drawback of not being able to incorporate real-world dietary exposure variations among different populations. In contrast, the latter exhibits the likelihood of chemical exposure by incorporating variability and uncertainty into analysis, providing a more accurate risk assessment of toxic elements via food or TCM consumption [24,25]. For example, Wu et al. (2024) [9] evaluated the risk of mycotoxins in 96 kinds of beers on the Chinese market by using MCS, and it was found that beer intake made a significant contribution to the exposure of aflatoxins (AFs) and DON, particularly among males. Liu et al. (2024) [21] used MCS to evaluate the risk index of 26 mycotoxins in coix seed and found that AFB1, OTA, and DON pose potential risks to human health. However, exposure assessment method using MCS has not been reported in complex matrix Platycladi semen samples regarding mycotoxins.

In the present study, a highly sensitive and rapidly modified QuEChERS coupled to UPLC-MS/MS method was established for the simultaneous quantification of 19 mycotoxins in 190 batches of Platycladi semen obtained from various sources in China. Then, the dietary exposure to these mycotoxins through consumption of Platycladi semen was evaluated using MCS method. This is the first systematic and comprehensive study to investigate mycotoxins contamination in Platycladi semen and to assess human exposure risk using MCS, offering valuable data to safeguard consumers from potential health risks associated with mycotoxin contamination.