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Factors impacting life stage-specific sensitivity to chemicals include toxicokinetic and toxicodynamic changes. To evaluate age-related differences in the biochemical and behavioral impacts of two typical N-methyl carbamate pesticides, we systematically compared their dose-respo...

Electroencephalography (EEG) is often used as an apical measure of multiple types of central nervous system (CNS) changes, while biomarkers in blood may serve as predictors for adverse outcomes. Correlation between these two measures would suggest that certain changes in biomarke...

There is increasing emphasis on the use of biomarkers of adverse outcomes in safety assessment and translational research. We evaluated serum biomarkers and targeted metabolite profiles after exposure to pesticides (permethrin, deltamethrin, imidacloprid, carbaryl, triadimefon...

Assessing the health risks of the thousands of chemicals in use requires both toxicology and pharmacokinetic (PK) data that can be generated more quickly. For PK, in vitro clearance assays with hepatocytes and serum protein binding assays provide a means to generate high throughp...

Concentrations of polybrominated diphenyl ethers (PBDEs), pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons were measured in 136 fish from 14 remote lakes in 8 western U.S. National Parks/Preserves between 2003 and 2005 and compared to human and w...

Multiple daily exposures to the herbicide atrazine have been reported to suppress the surge of luteinizing hormone (LH) in both cycling female rats and those that are ovariectomized (OVX) and exogenously primed with steroids. Additional studies have also found elevations in both ...

The Markov Chain nest productivity model, or MCnest, quantitatively estimates the effects of pesticides or other toxic chemicals on annual reproductive success of avian species (Bennett and Etterson 2013, Etterson and Bennett 2013). The Basic Version of MCnest was developed as a...

Benchmark doses (BMDs), defined as doses of a substance that are expected to result in a pre-specified level of "benchmark" response (BMR), have been used for quantifying the risk associated with exposure to environmental hazards. The lower confidence limit of the BMD is used as...

Over the last several years we have conducted both laboratory and field studies to develop a better understanding of the movement of chlorinated organic compounds through aquatic ecosystems, with special emphasis on the differential movement of these compounds due to physical/che...

The site was used to manufactured specialty intermediate chemicals for the producers of dyes, pharmaceuticals, cosmetics, herbicides, and pesticides. he herbicide Fenac (2,3,6-trichlorophenylacetic acid) is a major on- and off-site contaminant. ne hundred twenty -eight soils were...

A Soil-plant-water microcosm was used to develop a data base for pesticide transport and metabolism and to determine the effects of varying environmental conditions and/or components on chemical movement in a terrestrial ecosystem. The system was used in a comparative transport s...

The immune system defends the body against infectious agents and in some cases tumor cells. On the other hand, immune reactions to foreign substances that would otherwise be relatively innocuous (e.g., certain chemicals, pollens, or house dust) can result in allergic reactions t...

In accordance with EPA's mission to minimize risks to human health and to safeguard ecological integrity, the EPA Office of Prevention, Pesticides, and Toxic Substances (OPPTS) is committed to assessing and mitigating any risk posed by biotechnology-derived crops. Consequently, ...

Contaminated sport fish consumption may result in exposure to various reproductive and developmental toxicants, including pesticides and other suspected endocrine disruptors. We investigated the relation between maternal sport fish meals and risk of major birth defects among infa...

Pyrethroids are neurotoxic insecticides used in a variety of agricultural and household activities. Due to the phase-out of organophosphate pesticides, the use of pyrethroids has increased. The potential for human exposure to pyrethroids has prompted pharmacodynamic and pharmac...

Carbaryl and propoxur are N-methyl carbamate pesticides (NMCs) which are part of the EPA’s cumulative risk assessments for NMCs. These NMCs inhibit cholinesterase (ChE) activity and may lead to cholinergic disruption of CNS function. We used decreases in the PhAD of FEPs to indic...

The U.S. National Park Service, Environmental Protection Agency, and U.S. Geological Survey developed a screening program to characterize pharmaceuticals and personal care products (PPCP), wastewater indicators, and pesticides (collectively referred to as Contaminants of Emerging...

Some organophosphate pesticides (OPs) induce chromosome aberrations (CA) in experimental systems and may be genotoxic in persons exposed to home-use levels of OPs. However, the genotoxic effects of OPs have not been studied extensively in environmentally exposed children, such a...

Evaluating the potential neurodevelopmental effects of thyroid disrupting chemicals like flame retardants, perfluorinated compounds, and pesticides is challenging. While current regulatory tests attempt to determine if these chemicals may affect the developing brain, existing str...

Various cages are frequently used in assessing the effects of pesticides on non-target animals. In some cases, small animals offer advantages over larger ones because they may be more economical to raise in the laboratory or to purchase; immature stages often are more sensitive t...

Can flu-like illness be an indication of recent organophosphate pesticide exposure in preschool children? P Mendola*, D Barr, D Walsh, S Hern, S Rhoney, L Needham, E Hilborn, M Gonzales, C Carty, G Robertson, J Creason (US EPA, ORD, NHEERL, Research Triangle Park, NC 27711)<br><...

Carbonyl sulfide (COS) is an intermediate in the production of pesticides and herbicides, and is a metabolite of the neurotoxicant carbon disulfide. The potential neurotoxicity of inhaled COS was investigated in F344 rats. Male rats were exposed to 0, 75, 150, 300, or 600 ppm COS...

The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. eoplasia was observed in oysters after 30 and 60 days ...

Many non-scientists treat "ecology" and "environmentalism" as roughly interchangeable words, thus the word "ecologist" commonly has come to signify a particular part of the political spectrum. As used in the scientific community and in this presentation, however, ecology is loos...

The marine diatom, Skeletonema costatum, was exposed to the pesticides hexachlorocyclopentadiene, EPN, chlorpyrifos, carbophenothion, and Atrazine and examined for death of cells with Evans blue, a mortal stain. All pesticides caused death of cells, but significant mortality occu...