“…Estrogenicity can vary by a factor of 10 depending on the structure of the alkyl chain, with increased branching in the benzylic position associated with increased estrogenicity (Kim and others, 2004;Routledge and Sumpter, 1996). The biodegradability of 4-NP is reported to decrease with increasing degree of nonyl-group branching (Corvini and others, 2004;Corti and others, 1995;Van Ginkel, 1996). In contrast, efficient biodegradation has been reported for the linear chain isomer (4-n-NP) (Corvini and others, 2004;Corti and others, 1995;Van Ginkel, 1996;Bradley and others, 2008).…”