Found earthworms that contain chemicals from household and animal manure

The earthworms studied in agricultural fields have been found to contain organic chemicals from household products and fertilizers, suggesting that these substances are entering the food chain.

Fertilizers and biosolids are solid by-products of the wastewater treatment process that are used as fertilizer for fields. Earthworms continue to eat soil as a nourishment and can accumulate chemicals in the soil.

The investigated chemicals may be indications of animal and human waste sources, including strong chemical components in household products such as bleach and anti-bacterial soaps and flavoring agents. aromatic and pharmaceutical products. Some of the chemicals found are naturally available such as xterol and plant xterol and aroma. All of these chemicals tend to concentrate in the process of sorting and sorting municipal waste and are considered as human-induced indicator waste (AWI for short).

The scientist collected earthworms from a cultivated soybean field with bio-solid.The earthworms analyzed have 77 different chemicals;and 20 chemicals found in earthworms.(Photo: USGS)

US geological survey scientists and their colleagues from Colorado State University at Pueblo published their new findings in Environmental Science and Technology. Research results show that organic chemicals introduced into the environment through the application of biosolids and fertilizers are transferred to earthworms and into the food chain .

The researchers found 28 AWI substances in biosolids applied for the first time in a soybean field and 20 AWIs in earthworms in the same field. Similar results were found in the fields where pig manure was used. Some compounds found in earthworms are concentrated from fields using both biosolids and fertilizers, including phenol (disinfectant), tributylphosphate (antifoam and flame retardant), benzophenone. (inhibitor - a substance used to preserve, bind or stabilize another substance), trimethoprim (antibiotic), and musk synthetic galaxolide and tonalide. Bleaching metabolites and anti-bacterial triclosan are found in earthworms from fields using bio-solids rather than in fertilizer fields.

Biosolids are made from solid sludge by treating wastewater in wastewater treatment plants. Biosolids are used by farmers, flower growers and homeowners as fertilizer when they meet the US and local Environmental Protection standards for nutrient, metal and germ content. sick. Every year, about half of the 8 million tons of US-produced dry biosolids are used for fields. Biological soils contain a lot of AWI compared to the level of wastewater discharged by plants. In addition, 1.3 million livestock farms in the United States provide 500 million tons of fertilizer annually, which is also a widely used fertilizer for crops in the fields.

This study is part of the long-term effort of the USGS Hydrology Program to determine the fate and effects of chemicals in the emerging concerns of underwater and terrestrial environments. . At the same time, it aims to provide water managers with objective information to confirm the progress in implementing effective water resource management. This study is partially supported by the Research Corporation Cottrell College Award and the Research Department of Eastern Washington University.