Many pharmaceutical compounds are active at very low doses, and a portion of them regularly enters municipal sewage systems and wastewater-treatment plants following use, where they often do not fully degrade. Two such compounds, carbamazepine and lamotrigine, have been detected in wastewater effluents, surface waters, drinking water, and irrigation water, where they pose a risk to the environment and the food supply.
A BARD-funded study was recently run by Prof. Thomas Borch, Environmental Soil Chemistry lab at Colorado State University, Prof. Yitzhak Hadar and Dr. Tamara Polubesova, The Robert H. Smith Faculty of Agriculture, Food and Environment, at the Hebrew University in Israel, on the environmental fate of antiepileptic drugs and their metabolites. These compounds are expected to interact with organic matter in the environment, but little is known about the effect of such interactions on their photodegradation, biodegradation, sorption, and transport in our soil and water systems.
All project objectives were promoted as a result of the cooperation, through meetings, correspondence, shared experiments, and co-authorships involving the Israeli and US research groups. These activities included planning sessions, joint trainings, sample and data analysis, and critical reviews of everyone’s work and communication of results. The combined expertise of the Israeli and US research groups permitted thoughtful and comprehensive discussions about hypotheses and results.
With respect to agriculture, the researchers determined that soil organic matter levels govern the sorption of lamotrigine and carbamazepine by agricultural soils, and observed reversible sorption, suggesting the potential for leaching or plant uptake over time.
They also demonstrated that the type of soil and organic matter will affect both sorption and desorption in agricultural soils. This information could have special significance when composted biosolids or treated wastewater are applied to soils, especially considering the potential for plant uptake. The data on biodegradation by P. ostreatus suggests the possibility of effective remediation strategies for biosolids and treated wastewater before they are applied to soils. The data on photodegradation might help to predict the persistence of contaminants and their degradation products in surface waters used for irrigation.
The success of this collaboration is reflected in its achievements as both the Israeli and the American researchers found the cooperation valuable and intend to continue working together. The work in this research project was further enhanced by William Bahureksa a Colorado State University graduate student how came to Israel on a BARD fellowship grant.
BARD- the U.S-Israel Binational Agricultural Research and Development Fund, established in 1979, is a competitive funding program that supports collaborative agricultural research in areas of mutual interest to the U.S and Israel. BARD has funded outstanding agricultural science activities by leading researchers from the two countries. Its projects cover all phases of agricultural research and development, including integrated projects and strategic and applied research.