ABSTRACT
The estimation of chemical concentrations in wildlife foods, such as plant foliage, is often performed for risk assessments at contaminated sites. Regression models and uptake factors for use in estimating the uptake of inorganic elements from soil by above-ground plant tissues were derived in this study. These included models for arsenic, cadmium, copper, lead, mercury, nickel. selenium, and zinc. Models were developed using published data from soil contaminated in the field and were validated using measured concentrations from two contaminated sites. Single-variable regression models of log-transformed concentrations in plants versus log-transformed concentrations in soil are generally recommended over simple uptake factors for use in estimating plant uptake of inorganic contaminants in ecological risk assessments. Multiple regression models with soil concentration and pH as the variables are also recommended for estimating the uptake of four chemicals (cadmium, mercury, selenium, and zinc) by plants. Models for use in screening risk assessments, i.e., the upper 95% prediction limits on the regressions, are recommended to provide conservative estimates of uptake of inorganic chemicals by plants.
Subject(s)
Metals, Heavy/pharmacokinetics , Models, Theoretical , Plant Leaves/chemistry , Soil Pollutants/pharmacokinetics , Regression Analysis , Risk Assessment , Tissue DistributionSubject(s)
Animals, Wild , Environmental Pollutants/toxicity , Models, Biological , Toxicology/methods , Alkaloids/toxicity , Animals , Birds , Carbamates/toxicity , Ecology , Humans , Hydrocarbons, Chlorinated/toxicity , Mammals , Organophosphates/toxicity , Pesticides/toxicity , Risk Assessment , Species SpecificityABSTRACT
The growth and biological characteristics of isolates of Ornithobacterium rhinotracheale (ORT) from commercial broiler chickens in the mid-Atlantic region of the U.S.A. appear to be identical to those previously reported in the literature. The clinical disease and lesions are also similar to those reported from other poultry growing regions including South Africa and Europe. The diagnostic cases included in this report were often associated with known respiratory pathogens, namely, lentogenic Newcastle disease virus, and infectious bronchitis virus, and Escherichia coli bacteria. The role of ORT in the disease cases presented in this report is unclear.
