DEVELOPMENT OF A FAST SCREEN (ON-SITE) ANALYTICAL ASSAY FOR PYRIDINE HERBICIDES IN ANIMAL WASTE AND COMPOST

The object of this proposal is to develop a new analytical method (lateral flow immunochromatographic device) for the rapid and on-site detection of pyridine carboxylic acid herbicides (aminopyralid, clopyralid, picloram and triclopyr) in compost and animal waste. The availability of a screening method to determine if compost is safe to be used in crops and ornamental flowers will greatly help protect the composting industry from law suits and growers from damaged crops. This project will also help reduce the adverse impact of animal manure on the environment, assure that crops labeled as organic are free of pyridine carboxylic acid herbicide chemical inputs, and to help optimize manure management. Current analytical methods for quantifying the concentration of pyrimidine carboxylic acid herbicides in compost and waste products, include solvent extraction, followed by instrumental analysis. These methods are time consuming, labor intensive, and require in some cases the use of flammable and/or toxic solvents. A faster, customer/environmentally friendly and less expensive method such as a lateral flow immunochromatographic device (dipsticks) for the detection of pyrimidine carboxylic acid herbicides could find a broad application in the composting, agricultural (crops) and environmental monitoring (water) markets. The proposed analytical test will allow establishment of efficient and cost-effective screening programs that could be used quickly on-site for the analysis of compost ad other environmental matrices, therefore protecting compost producers, users, and the environment. The strategy in this proposal will be performed in 2 phases. Phase I, focuses on creating polyclonal antibodies and several hybridoma cell lines that produce monoclonal antibodies, which react with the pyridine carboxylic acid herbicides of interest with sufficient selectivity, affinity and avidity to be utilized in a commercial dipstick type immunoassay system. Once these antibodies are developed, phase II will be started, this phase will involve the development and validation of a commercial dipstick immunoassay format for on-site testing, to detect the target herbicides in animal waste such as compost, solid manure, farmyard waste and manure slurry, as well the required extraction procedures to be able to quickly and easily analyze the extracts from those matrices. One of our approaches to obtain broad selectivity of the immunoreagents towards the 4 target analytes will be to prepare antibody cocktails. The proposed research is in line with several of USDA's strategic goals: 1) will expand domestic marketing opportunities for compost and manure byproducts and strengthen risk management by allowing to monitor those product for contamination with pyridine carboxylic acid herbicides that have potential to destroy crops, therefore, helping farmers, researchers and compost facilities in their decision-making process; 2) develop alternative markets for agricultural byproducts; 3) safeguard agriculture from herbicide threats i. e. if contaminated manure were to be used as fertilizer.