Screening bioassay

Finally, it is interesting to note that brominated derivatives of NP included in the present study, estrogenic in the E-Screen bioassay, were proposed to be fat-soluble [30], In fact, as non-ionic surfactants, these molecules have a hydrophilic and a hydrophobic part [31]. The presence of these brominated compounds in fat tissue of humans or animals has yet to be demonstrated. However, if they do bioaccumulate in adipose tissue, as their fat solubility suggests, they may account for the xenoestrogen burden alongside organohalogenated compounds. 

In the E-Screen bioassay, LAS was not effective in promoting cell proliferation (Table 7.3.3). This compound was tested at concentrations of up to 100 pM with no evidence of cellular toxicity. The antiestrogenic effect of this compound was also measured but all samples tested were negative. Because it has been suggested that surfactants of the alkylbenzene sulfonate type are readily degradable and transformed into sulfophenyl carboxylates or SPCs, an important number of SPCs were assayed in the E-Screen test. These SPCs did not induce cell proliferation of MCF7 cells. 

Estrogenicity of LAS, SPCs and other compounds in the E-Screen bioassay... 

At the time of its conception, the PEEP index integrated the results of a selection of practical small-scale screening bioassays which included the Vibrio fischeri bioluminescence inhibition test, the Selenastrum capricornutum growth inhibition... 

Specific molecular bioassays can be indispensable in screening compounds that act on certain biosynthetic pathways or enzymes. For example, recent patents report a screening bioassay for detection of herbicides that specifically inhibit the plant purine biosynthetic pathway. Many enzymes are involved in this... 

Application of bioassays for toxicity screening Bioassays used as screening tools aim at the identification of toxic samples. Short test duration, sensitivity, reliability and ease of use are favourable characteristics for test selection. Screening test applications include ... 

Van der Heever JA, Grobbelaar JU. In vivo chlorophyll a fluorescence of Selenastrum capricornutum as a screening bioassay in toxicity studies. Arch Environ Contam Toxicol 1998 35 281-286. 

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