[Research Process on the Combined Pollution of Microplastics and Typical Pollutants in Agricultural Soils].

As a new type of environmental persistent pollutant， microplastics can not only have adverse effects on the ecosystem but also form complex pollution with co-existing pollutants in the surrounding environment， resulting in higher ecological and health risks. Based on the perspective of agroecosystems， this study focused on the combined pollution of heavy metals， pesticides， and antibiotics， which are three typical pollutants of farmland soil， as well as microplastics and discussed the adsorption-desorption behavior of heavy metals， pesticides， and antibiotics on microplastics. The influence of the structure and properties of microplastics， the physicochemical properties of pollutants， and environmental conditions on the adsorption and desorption behavior of heavy metals， pesticides， and antibiotics on microplastics was discussed. The influence of microplastics on the bioavailability of heavy metals， pesticides， and antibiotics in farmland soil and the internal mechanism were expounded. The existing problems and shortcomings of current research were pointed out， and the future research direction was proposed. This study can provide a scientific reference for ecological risk assessment of the combined pollution of microplastics and typical pollutants in farmland soil.

[Influence of Four Kinds of PPCPs on Micronucleus Rate of the Root-Tip Cells of Vicia-faba and Garlic].

In order to determine the degree of biological genetic injury induced by PPCPs, the genotoxic effects of the doxycycline (DOX), ciprofloxacin (CIP), triclocarban (TCC) and carbamazepine (CBZ) in the concentration range of 12.5-100 mg · L⁻¹ were studied using micronucleus rate and micronucleus index of Vicia-fabe and garlic. The results showed that: (1) When the Vicia-faba root- tip cells were exposed to DOX, CIP, TCC and CBZ, micronucleus rates were higher than 1.67 ‰ (CK1), it was significantly different from that of the control group (P < 0.05), and the micronucleus index was even greater than 3.5; With the increasing concentrations of the PPCPs, the micronucleus rates first increased and then decreased. (2) When the garlic root tip cells were exposed to DOX, CIP, TCC and CBZ respectively, the micronucleus rates were less than those of the Vicia-faba, while in most treatments significantly higher than that of the control group (0.67‰). The micronucleus index was higher than 3.5 in the groups exposed to CIP with concentrations of 25, 50, 100 mg · L⁻¹ and TCC and CBZ with concentrations of 25 mg · L⁻¹; With the increase of exposure concentrations, the micronucleus rate showed a trend of first increasing and then decreasing as well. (3) Under the same experimental conditions, the cells micronucleus rates of the garlic cells caused by the four tested compounds were significantly lower than those of Vicia-faba. (4) The micronucleus index of the root tip cells of Vicia-faba and garlic treated with the four kinds of compounds followed the order of CIP > CBZ > TCC > DOX. These results demonstrated that the four compounds caused biological genetic injury to root-tip cells of Vicia-faba and garlic, and the genetic damage caused to garlic was significantly lower than that to Vicia-faba. The damages caused by the four kinds of different compounds were also different.