{"id":37767,"date":"2025-02-25T00:01:36","date_gmt":"2025-02-25T05:01:36","guid":{"rendered":"https:\/\/beyondpesticides.org\/dailynewsblog\/?p=37767"},"modified":"2025-02-25T11:13:40","modified_gmt":"2025-02-25T16:13:40","slug":"interactions-between-microplastics-and-pesticides-exacerbate-their-environmental-health-threat-studies-find","status":"publish","type":"post","link":"https:\/\/beyondpesticides.org\/dailynewsblog\/2025\/02\/interactions-between-microplastics-and-pesticides-exacerbate-their-environmental-health-threat-studies-find\/","title":{"rendered":"Microplastics Interact with Pesticides, Exacerbating Environmental Health Threats, Studies Find"},"content":{"rendered":"

(Beyond Pesticides<\/em>, February 25, 2025) A literature review of over 90 scientific articles in Agriculture<\/em><\/a> documents microplastics\u2019 (MPs) increase in the bioavailability, persistence, and toxicity of pesticides used in agriculture. The interactions between MPs and pesticides enhance the threat of pesticide exposure to nontarget organisms, perpetuates the cycle of toxic chemical use, and decreases soil health that is vital for productivity.<\/p>\n

\u201cThe increasing presence of MPs in agricultural ecosystems has raised concerns about their impact on pesticide bioavailability, efficacy, and environmental behavior,\u201d says study author Kuok Ho Daniel Tang, PhD, a global professor in the Department of Environmental Science at the University of Arizona. He continues, \u201cThese synthetic particles interact with pesticides through adsorption and desorption processes, altering their distribution, persistence, toxicity, and uptake by plants and other organisms.\u201d<\/p>\n

Microplastics in the Environment<\/em><\/p>\n

As Beyond Pesticides has previously reported<\/a>, microplastics are ubiquitous and threaten not only human health but all wildlife in both aquatic and terrestrial ecosystems. The universal distribution of plastics means that they cannot be avoided. Humans and other organisms take up plastics in the form of microparticles and nanoparticles by inhalation, ingestion, and skin contact every day. Microplastics are about the width of a human hair<\/a>; nanoplastics are much smaller, about twice the width of a DNA strand. Larger pieces of plastic are ground down to these tiny sizes by weathering, temperature, biological processes, and chemical conditions. (See additional Daily News<\/em> coverage on microplastics here<\/a>, here<\/a>, here<\/a>, and here<\/a>.)<\/p>\n

In agriculture, the primary sources of microplastics are plastic mulching, coatings on pesticides, and fertilizers such as biosolids<\/a>, in addition to the particles carried to the fields by wind and water. As Dr. Tang says: \u201cMPs are defined as plastic fragments measuring less than 5 mm in size and can either result from the breakdown of larger plastic waste (secondary MPs) or be produced intentionally for specific uses (primary MPs), like in cosmetics, pharmaceuticals, and industrial applications. Owing to their diminutive size, durability, and widespread presence, MPs have been recognized as a global pollutant that can interact with various environmental contaminants, including pesticides.\u201d<\/p>\n

Recent research on interactions with antibiotics shows that MPs can act as a vehicle, \u201cextending their presence in the environment and aiding in the development and spread of antibiotic-resistance genes<\/a>,\u201d Dr. Tang states. (See studies here<\/a> and here<\/a>.) He continues, saying that these results have led to \u201cgrowing concern that the co-occurrence of MPs and pesticides may exacerbate the environmental risks associated with these contaminants through complex physicochemical interactions.\u201d<\/p>\n

The interaction between MPs and pesticides depends on various factors, such as the physical and chemical properties of both the MPs and pesticides involved, as well as the environmental conditions they are subjected to, including pH, temperature, salinity, and organic matter content. The pervasiveness of a pesticide in the environment after contact with MPs can be altered based on their modes of action, including systemic pesticides that are absorbed by plants and transported throughout their tissues and contact pesticides that kill pests with direct contact.<\/p>\n

Adsorption and Bioavailability<\/em><\/p>\n

Bioavailability of pesticides represents \u201cthe extent to which a pesticide is accessible to organisms or biological systems, such as plants, microbes, or animals, for absorption, uptake, or interaction,\u201d Dr. Tang shares. \u201cIt determines how effectively a pesticide can exert its intended effects, such as killing pests or controlling weeds, and it also influences the pesticide\u2019s potential for environmental contamination and toxicity,\u201d he continues. Through the interaction with MPs, the bioavailability of pesticides can be altered by the mechanism of adsorption, where particles from the pesticides can adhere to the plastic\u2019s surface.<\/p>\n

Relevant studies find:<\/p>\n