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Pesticide absorption

Berteau, P.E. and Mengle, D.M. (1985) An Assessment of the Hazard from Pesticide Absorption from Surfaces, Community Toxicology Unit, California Department of Health Services, Berkeley, May 17, 1985. [Pg.105]

Woollen, B.H. (1993) Biological monitoring for pesticide absorption, Am. Occup. Hygiene, 37 525-540. [Pg.183]

To relate [pesticide] absorption to the duration of exposure of the animal and... [Pg.218]

Plant uptake. Pesticide uptake by plants has not been considered in most modeling efforts. This is primarily due to an almost total lack of quantitative experimental information available to the modeler, and the presumption that the absolute mass of pesticide absorbed by the plant is small compared to the mass remaining in the system. Due to these considerations, modelers have apparently assumed that any inaccuracy in simulation of pesticide fate that results from not considering plant uptake is within the "noise" of inaccuracies produced by other assumptions about the physical, chemical, and biological processes operating in the system. While this assumption is unproven for pesticide absorption, it clearly cannot be accepted for water absorption by the plant (the U(z,t) term in Equation 4). Plant extraction of water greatly influences water flux, which affects pesticide... [Pg.337]

Baker s yeast cells Saccharomices cerevisae) were successfully immobilized on to silica gel and used in selective online trace enrichment of selected pesticides, including linuron, in various types of natural waters.This technique relies upon the fact that microorganisms are able to absorb pesticides from water in the environment. Cell membranes contain many classes of lipids and lipoproteins, which contribute to pesticide absorption. Since the diffusion rate across membranes is inversely proportional to molecular size, low-molecular weight compounds, such as pesticides, can be extracted from water and isolated by naturally occurring high-molecular weight substances, such as humic acids, which are abundantly present in environmental waters. [Pg.945]

Topical exposure to organophosphate (OP) and carbamate (CM) pesticides remains an important route for exposure to humans and animals. As in many subdisciplines in toxicology and other sciences, interpretation of pesticide deniial absorption data is highly dependent on the model systems u.sed to generate the data. This chapter discusses studies of pesticide absorption in the context of the experimental and theoretical approaches used to assess absorption, This field was reviewed by Baynes and Riviere (2001). which should be consulted for further details. This review highlighted the overarching importance of experimental design and subsequent interpretation of pesticide data reported in the literature since these factors often overshadow differences in absorption and subsequent toxicity between individual pesticides,... [Pg.411]

A similar conclusion was derived from analysis of how data are used in making pesticide risk assessments, where the authors concluded that the inability to match a specific exposure scenario to available data (c.g., species and duration of dosing) led to overestimation of absorption and thus risk Ross et al., 2000). The take home lesson from this chapter is that the experimental conditions under which pesticide absorption studies are conducted often overshadow differences between individual compounds, as can easily be appreciated in the classic studies comparing absorption of pesticides in mice (Shah el ai, 1981) versus humans (Fcidmann and Maibach, 1974). [Pg.419]

The major challenge facing a critical asse.ssment of pesticide absorption is that very few data sets, either across pesticides or for dosing factors within a specific pesticide, are available for analysis. This is the major limitation to compiling large databases of comparative pesticide absorption because the previous factors confound any analysis. Building such a comprehensive dermal absorption database of pesticides would also facilitate development of more robust QSPeR models that ultimately would facilitate the risk assessment process. [Pg.419]

I thank Dr. Ronald Baynes for his invaluable input and guidance in tutoring me on ihe fine points of experimentally assessing dermal pesticide absorption. [Pg.419]

The presence of fonnulation surfactants and solvents, which will facilitate skin penetration of the pesticide. Absorption rate is more effective for lipophilic materials. Some U V-absorbing chemicals can act as skin penetration enhancers, which may increase the pcrcutancou.s aKsoiption of pesticides and other formulation chemicals (Morgan... [Pg.569]

Permethrin absorption could have been influenced by the presence of other additives present in any given pesticide formulation and any other chemical that may have been present on the skin of the veterans before or after they dressed with the permethrin-impregnated uniforms. Commercial pesticides are often formulated with several important performance additives, such as surfactants and solvent vehicles (Seaman, 1990), and the effect of these formnlation additives on pesticide absorption has been reported in our laboratory (Baynes and Riviere, 1998). [Pg.164]

Percutaneous absorption studies using in vitro techniques appear to be of value in the assessment of pesticide absorption as well as with other types of compounds. As with any procedure, precautions may need to be taken in certain steps to ensure the accuracy of the data. For water-insoluble compounds, the llpophilicity of the... [Pg.40]

Research on the parameters and kinetics of pesticide absorption from human dermal contact, on the measurement of absorbed residue... [Pg.422]


See other pages where Pesticide absorption is mentioned: [Pg.66]    [Pg.218]    [Pg.26]    [Pg.111]    [Pg.43]    [Pg.208]    [Pg.413]    [Pg.414]    [Pg.415]    [Pg.415]    [Pg.416]    [Pg.417]    [Pg.417]   
See also in sourсe #XX -- [ Pg.175 , Pg.177 ]




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