Invasive plant-derived biochar inhibits sulfamethazine uptake by lettuce in soil

Veterinary antibiotics are frequently detected in soils posing potential contamination of food crops. Sulfamethazine (SMT) uptake was investigated by lettuce (Lactuca sativa L.) grown in the soils treated with/without biochar derived from an invasive plant, burcucumber (Sicyos angulatus L.) (BBC700). Soils were contaminated with SMT at 5 and 50 mg kg−1, and treated with/without 5% BBC700 (w w−1). The lettuces were harvested after 5 weeks of cultivation and were analyzed for SMT by a high performance liquid chromatography-tandem mass spectrometry after solid-phase extraction. With 5% BBC700, the uptake of SMT was reduced by 86% in the soil spiked with 5 mg kg−1 SMT compared to the control whereas a 63% reduction was observed in the soil spiked with 50 mg kg−1 SMT. Application of BBC700, into soils effectively reduced the SMT uptake by lettuce.