Chinese scientists at Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science of Chinese Academy of Sciences (CAS) developed a nanocomposite to simultaneously remove some substances in pigs’ urine that do harm to human health.

This work published in Environmental Science: Nano was conducted by WU Zhengyan's team.

The harmful substances they were targeting were chlortetracycline hydrochloride (CTC), a kind of antibiotics and As, a non-metallic element, which have been widely added to feed to treat infectious diseases and promote the growth of pigs.

However, just a small portion of intake antibiotics and As are generally absorbed, and a large amount of them are excreted along with pigs’ urine, through which the substances tend to be migrated into water and soil, causing contamination with synergy toxicity.

Until now, a variety of technologies have been developed to remove antibiotics or As from contaminated water and soil. Nevertheless, they all could only remove either antibiotics or As rather than remove both at the same time, dominantly limiting their extensive application.

To get a simultaneous removal of these two, WU's team developed a nanonetwork-structured composite which could help to realize it in application.

This nanocomposite was synthesized using amido-functionalized Fe₃O₄ microspheres (AFFM) and MnO₂, and the obtained nano system was named as AFFM/MnO₂ (OAM).

To obtain the optimal OAM, researchers investigated the removal efficiency of OAM on CTC and trivalent arsenic (As(III)) in water under different conditions.

They then took a closer look at the removal performance of OAM on CTC and As(III) in SUAS and soil, and analyzed the interactions among OAM, CTC, and As to reveal the mechanism on CTC and As(III) removal.

Additionally, pot experiments were performed to prove the removal performance of OAM for CTC and As. OAM could effectively reduce the uptake of CTC and As by zebrafish, water spinach, and pakchoi.

This work provided a method to remove CTC and As(III) simultaneously in SUAS and soil, which may be highly valued in reducing CTC and As(III) pollution.

The study was supported by the Youth Innovation Promotion Association of CAS, the Science and Technology Service Programs of CAS, the Science and Technology Major Project of Anhui Province, and the Environmental Protection Department of Anhui Province.

Schematic illustration of the mechanism. (Image by WANG Dongfang)