Show-Me State Times

Farmers are increasingly turning to polymer-coated, controlled-release fertilizers (PC-CRFs) as a method to enhance crop health. These fertilizers provide nutrients gradually, minimizing waste compared to traditional approaches. However, a recent study led by Maryam Salehi from the University of Missouri highlights an environmental concern linked to these fertilizers—microplastic pollution.

According to Salehi, "In PC-CRFs, the plant nutrients are enclosed within a microcapsule. This microcapsule is designed to slowly release the fertilizers into the farmland over time. The non-biodegradable coatings left over after this process is complete can be considered microplastics." The study reveals that as these coatings break down in soil, they release small plastic particles into the environment.

This discovery prompts concerns about potential long-term impacts on human and animal health due to microplastic pollution. Prior research has already identified microplastics in agricultural lands, prompting Salehi's team to investigate further how much plastic is released and what types of plastics are present.

Salehi advises farmers to consider more sustainable alternatives like biodegradable coatings until more data is available. For those using PC-CRFs, she recommends implementing stormwater management strategies to reduce runoff of microplastics into water bodies.

The study also calls for additional research to understand better the effects of PC-CRFs on different soil environments and conditions. Salehi stated, "Various soil environments, moisture conditions and soil organisms can impact the disintegration of the microcapsule differently." She emphasized that more investigation is necessary due to variations in plastics used in PC-CRFs.

The findings were published in the Journal of Hazardous Materials with co-authors Anandu Nair Gopakumar, Arghavan Beheshtimaal, Alexander Ccanccapa-Cartagena from Mizzou; and Linkon Bhattacharjee and Farhad Jazaei from the University of Memphis.