OBJECTIVE  To evaluate the joint exposure risk of heavy metals and harmful elements in Tongxinluo Capsules by using the characteristic parameters of secondary prevention of ischemic stroke(IS), so as to fill the application gap of the risk assessment technology of heavy metals and harmful elements in traditional Chinese medicine in the prevention and treatment of IS.

METHODS  Exposure characteristic parameters were established based on the characteristics of IS incidence and secondary prevention medication. In vitro gastrointestinal simulation digestion ICP-MS technology was used to determine the contents of lead(Pb), cadmium(Cd), arsenic(As), mercury(Hg), and copper(Cu) in 11 batches of Tongxinluo capsules. The hazard index to different target organs, average daily intake, and the target hazard index, exposure limit, and carcinogenic risk at different medication years (0.5, 1, 2, 10, 20, 30 years) were calculated to evaluate their joint exposure risk.

RESULTS  The joint exposure risk of five elements to nerves, blood, skin, and testes was relatively low under a single day dosage, while the joint exposure risk to kidneys and cardiovascular systems should be taken into account. Pb exposure exceeded the ICH Q3D daily allowable exposure limit and ranks first among target organ hazards. As the duration of medication increased, the non carcinogenic risk caused by the five elements increased. Among them, the non carcinogenic risk caused by the joint exposure of Cd, As, Hg, and Cu was low, while the non carcinogenic risk of Pb should be taken into account. In addition, the carcinogenic risk of the five elements were low.

CONCLUSION  The use of Tongxinluo capsules for secondary prevention of IS is generally safe, but the risk of Pb exposure caused by long-term use deserves attention.