A new mathematical model for analyzing data and predicting the effect of mixtures of toxic substances is presented as a generalized form of the concentration addition model. The proposed method, the generalized concentration addition (GCA) model, can be applied to mixtures with arbitrary strengths of interactions (synergistic or antagonistic). It requires mixture effect data for least 1 exposur...

Recent regulatory guidance for mixture risk assessments and for regulating pesticide chemicals recommends using information about the "mode" or "mechanism" of action of individual chemicals to predict dose response characteristics of mixtures. Dose addition is assumed for mixtures of chemicals that have similar mechanisms and response addition for those with dissimilar mechanisms. Three differe...

Understanding toxic effects on biological populations across generations is crucial for determining the long-term consequences of chemical pollution in aquatic environments. As a consequence, there is considerable demand for suitable statistical methods to analyze complex multigeneration experimental data. We demonstrate the application of a Bayesian mixture model (with random-effects) to asses...

Egg surface applications of microliter quantities of crude and refined oils of high aromatic content are embryotoxic to mallards (Anas platyrhynchos) and other avian species; applications of aliphatic hydrocarbons have virtually no effect. Mallard eggs at 72 h of development were exposed to a mixture of aromatic hydrocarbons or to aromatic compounds representative to those present in crude oil ...

Abstract Exposure to persistent organic pollutants (POPs), encompassing chlorinated (Cl), brominated (Br) and perfluoroalkyl acid (PFAA) compounds is associated with adverse neurobehaviour in humans animals, observed cause effects nerve cell cultures. Most studies focus on single POPs, whereas of complex mixtures are limited. We examined the a mixture 29 (Cl + Br + PFAA, named Total mixture), a...

The objective of this study was to investigate the capacity of decolorization and detoxification of the textile dyes Reactive Red 198 (RR198), Reactive Blue 214 (RB214), Reactive Blue 21 (RB21) and the mixture of the three dyes (MXD) by Penicillium simplicissimum INCQS 40211. The dye RB21, a phthalocyanine, was totally decolorized in 2 days, and the others, the monoazo RR198, the diazo RB214 an...

The Agency for Toxic Substances and Disease Registry (ATSDR), in collaboration with the Dutch Organization for Applied Scientific Research (TNO) Nutrition and Food Research Institute, is conducting studies to evaluate the role of chemical interactions in the expression of toxicity from low-level exposure to combinations of chemicals. The goal of this collaborative effort is to use a weight-of-e...

Parkinson's disease is an environmentally influenced, neurodegenerative disease of unknown origin that is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta of the brain. Arsenic is an environmental contaminant found naturally in ground water, industrial waste, and fertilizers. The initial goal of the present study was to determine if a mixture o...

Acute semistatic toxicity tests were carried out for 96 h with first zoeae and young crabs of Chasmagnathus granulata. Survival curves and LC50 (lethal concentration 50, the concentration which produces the death of 50% of the exposed population) indices for copper, zinc, cadmium, and lead were determined. Furthermore, mixture toxicity tests (Cd/Cu and Cd/Zn) with first-stage larvae were also c...

Biodegradation of crude oil and 7 different distillation products by Ralstonia picketti SRS and Alcaligenes piechaudii SrS was investigated. Crude oil degradation was above 80% after incubation of 20 days for both strains and their mixture. removal of short/long alkanes and BteX investigated was different, from 97% (for hexane degraded by the mixture of the isolates) to 22% (for tridecane degra...