As analytical capabilities in the early 2000s began to enable the detection of chemicals in environmental media at increasingly small concentrations, chemicals with the potential to cause adverse human and ecosystem health effects began to be found nearly ubiquitously worldwide. The types of chemicals that were targeted for analysis included natural and synthetic hormones, human and veterinary pharmaceuticals, chemicals in personal care products, novel pesticides, nanoparticles, microplastics, and other chemicals of natural and synthetic origin. The impacts of these chemicals on environmental and human health in many cases remain unknown. Collectively, these chemicals became known as "emerging contaminants" or "contaminants of emerging concern." Much progress has been made toward understanding the sources of these contaminants in the environment, the processes that control their fate and transport once they are released into the environment, and the ability of technology and/or best management practices to mitigate their occurrence. As the Journal of Environmental Quality (JEQ) celebrates its 50th anniversary, we sought to understand how publications in the journal have made impactful contributions in the research area of emerging contaminants. Here, we present the trajectory of publications in JEQ that have shaped knowledge in this field, highlight the importance of these contributions, and conclude with opportunities for JEQ to continue attracting high-quality emerging contaminants research.

HighlightsThree crop scenarios for eight dairy farm types were simulated using the Integrated Farm System Model.Cover cropping and interseeding each significantly reduced runoff losses, compared to the baseline, for most farm types.Interseeding averaged greater reductions in N, P, and sediment losses than cover cropping.Increases in average annual production costs were <2% of the baseline for most farm types.Abstract. Intensive agricultural activities are known to increase nutrient and sediment losses, leading to degraded water quality in receiving water bodies. In the Chesapeake Bay watershed, animal operations must reduce farm-level nutrient and sediment losses to meet federally mandated load reduction goals. This work investigated the potential water quality benefits and economic impacts of adopting post-harvest cover cropping or interseeded cover cropping on eight dairy farms representative of common operations in central Pennsylvania. The farms, simulated with the Integrated Farm System Model (IFSM), represented confined, organic, grazing, and Amish farming practices for dairy herds ranging in size from 35 to 150 lactating Holstein cows. Simulations were run for 25 years using observed weather data for Mifflin County, Pennsylvania, and for the dominant agricultural soil series in the county: Hagerstown silt loam. Model output included water balance results, nutrient and sediment loads, and farm-scale economics at an annual scale. Overall, simulation results showed that post-harvest cover cropping reduced N, P, and sediment by 18%, 17%, and 42%, respectively, while interseeding reduced loads by 49%, 41%, and 46%, respectively. Economic impacts of cover cropping and interseeding varied among farm types, but nearly all scenarios resulted in a net loss in profit compared to the baseline. However, annual economic losses were relatively minor: less than $28 ha-1 for cover cropping and $63 ha-1 for interseeding. Results suggest that the benefits of interseeding cover crops are greater for farms with larger portions of land in row crops with less perennial grassland. Interseeding necessitates purchasing additional equipment or custom hiring the seeding operation. These results have implications for cost-share incentive structures aimed at promoting adoption of cover crops and interseeding, especially for confined farms, which may otherwise experience financial losses if these practices are adopted. Keywords: Best management practice, Conservation, Economic evaluation, Erosion, IFSM, Integrated Farm System Model, Nutrient transport, Water quality.