RESUMO
Inductively coupled plasma mass spectrometry (ICP-MS) was applied to determine the concentrations of lead (Pb), cadmium (Cd) and arsenic (As) in Lindera aggregata (Sims) Kosterm. The physiologically based extraction test (PBET) digestion in vitro/Caco-2 cell model was established to investigate the bioaccessible contents of Pb, Cd and As in decoction of Lindera aggregata (Sims) Kosterm. The target-organ toxicity dose modification of HI method (TTD) was used to evaluate the cumulative risk caused by the combined exposure of the total levels of Pb, Cd and As in Lindera aggregata (Sims) Kosterm. and the bioaccessible contents in the decoction. The results showed that the total contents of Pb, Cd and As in 4 batches of samples were in the range of 2.901-3.872, 1.299-1.800 and 0.062-0.216 mg·kg-1, respectively. After transportation by Cacco-2 cells, the bioaccessible contents of Pb, Cd, and As in the decoction were in the range of 0.045-0.080, 0.070-0.112 and 0.004-0.018 mg·kg-1. The results of risk assessment showed that calculated by the total amounts of heavy metals in the Lindera aggregata (Sims) Kosterm., for the end points of nervous system, the cumulative risks of co-exposure of heavy metals in 3 batches of samples were of concern. After decoction and transportation by Caco-2 cells, for the end points of cardiovascular system, blood, nervous system, kidney and testis, the TTD modification of HI values of all batches of samples were less than 1, and the health risks were acceptable. The study provided methodology basis for a more objective assessment of the health risks of heavy metals and harmful elements in traditional Chinese medicine and for a more scientific limit standard of heavy metals and harmful elements.
RESUMO
Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the content of cadmium (Cd) and arsenic (As) in earthworms. A physiologically-based extraction test (PBET) digestion in vitro /MDCK cell model was established to investigate the bioaccessibility of Cd and As in earthworms. The hazard index (HI) method and the margin of exposure (MOE) method were used to assess the risks of the total content and the bioaccessible content of Cd and As. The results showed that the total content of Cd and As in six batches of earthworms ranged from 8.319 to 33.606 mg·kg-1 and from 0.532 to 16.412 mg·kg-1, respectively. After uptake by MDCK cells, the bioaccessibility of Cd in earthworms ranged from 10.13% to 64.16%, and the bioaccessibility of As was from 2.72% to 46.57%. The results of risk assessment showed that before uptake by MDCK cells, the MOE values of As and HI values of Cd for all batches of earthworms were greater than 1, which suggests that the risks of As are acceptable but the risks of Cd are unacceptable. After transportation by MDCK cells, except for one batch of earthworms, the HI values of Cd in the other five batches were less than 1, which suggests that the risks are at a safe level. This study provides important technical support for a more objective and scientific assessment of the health risks of heavy metals in traditional Chinese medicines, and for a more scientific and reasonable standard limit of heavy metals.