Uptake and Distribution Characteristic and Health Risk Assessment of Heavy Metal(loid)s in Platycodon Grandiflorum (Jacq.) A.DC. with Growth from a Medicinal Herb Garden of Xi’an, China

The different parts of Platycodon grandiflorum were collected from a medicinal herb garden to determine five heavy metal(loid)s (Pb, Cd, As, Hg, and Cu) contents at different growth stages. The data showed that the plant accumulated varying amounts of metal(loid)s in the order Cu > Hg > Pb > As > Cd. Five heavy metal(loid) concentrations decreased in the early growth stage and then increased in the flowering season. The contents of heavy metal(loid)s except Hg in the stem were relatively lower than other tissues. The flower of Platycodon grandiflorum can highly accumulate heavy metal(loid)s, especially for Cu in the flowering period. Pb, Cd, and Cu contents in stem generally increased with growth time, while Cd and Cu in root decreased during growth time. The average daily intake doses of five heavy metal(loid)s in the root of Platycodon grandiflorum were all below the safety guideline and the target hazard quotient was less than 1 .